Amnesia, Transient Global

Considering New and Emerging Treatment Strategies for Depression: Beyond STAR*D and the Monoamines

While the number of treatment options for major depressive disorder (MDD) has grown in recent years, the lack of quality data to guide optimal modality selection has lessened the potential impact of having a more diverse set of mechanistic approaches to treatment. The last attempt to investigate treatment sequencing for MDD was the Sequenced Treatment Alternatives for Relief of Depression Study (STAR*D), which gave rise to the concept of treatment-resistant depression (TRD) as a failure to respond to two or more monoaminergic antidepressants. However, a recent reanalysis of the STAR*D data indicates that most patients do not remit even when treated with multiple traditional antidepressants. Given these new results, labeling the majority of patients as treatmentresistant is not appropriate or useful. If monoamine-based drugs are not that effective for the majority of MDD patients, then it is necessary to consider the mechanistically distinct pharmacological and non-pharmacological treatment options that have emerged recently, including brain stimulation, glutamate receptor modulators, and psychedelic medicines. While these new treatment modalities have the potential to enhance patient outcomes, clinicians and patients currently lack a framework to guide their choices other than cost, feasibility, personal preference, and certain medical contraindications. Here, we review alternative treatment modalities for monoamine non-responders and consider the possibility that there will be new first-line therapies for MDD. We will review how treatment decisions for these patients are currently being made and how developments in precision psychiatry may help guide rational treatment selection in the future.

Significance of Beta-Blocker in Patients with Hypertensive Left Ventricular Hypertrophy and Myocardial Ischemia

Background: Arterial Hypertension (HTN) is a key risk factor for left ventricular hypertrophy (LVH) and a cause of ischemic heart disease (IHD). The association between myocardial ischemia and HTN LVH is strong because myocardial ischemia can occur in HTN LVH even in the absence of significant stenoses of epicardial coronary arteries.

Objective: To analyze pathophysiological characteristics/co-morbidities precipitating myocardial ischemia in patients with HTN LVH and provide a rationale for recommending beta-blockers (BBs) to prevent/treat ischemia in LVH.

Methods: We searched PubMed, SCOPUS, PubMed, Elsevier, Springer Verlag, and Google Scholar for review articles and guidelines on hypertension from 01/01/2000 until 01/05/2022. The search was limited to publications written in English.

Results: HTN LVH worsens ischemia in coronary artery disease (CAD) patients. Even without obstructive CAD, several pathophysiological mechanisms in HTN LVH can lead to myocardial ischemia. In the same guidelines that recommend BBs for patients with HTN and CAD, we could not find a single recommendation for BBs in patients with HTN LVH but without proven CAD. There are several reasons for the proposal of using some BBs to control ischemia in patients with HTN and LVH (even in the absence of obstructive CAD).

Conclusion: Some BBs ought to be considered to prevent/treat ischemia in patients with HTN LVH (even in the absence of obstructive CAD). Furthermore, LVH and ischemic events are important causes of ventricular tachycardia, ventricular fibrillation, and sudden cardiac death; these events are another reason for recommending certain BBs for HTN LVH.

Chlorogenic Acid: A Dietary Phenolic Acid with Promising Pharmacotherapeutic Potential

Phenolic acids are now receiving a great deal of interest as pervasive human dietary constituents that have various therapeutic applications against chronic and age-related diseases. One such phenolic acid that is being utilized in traditional medicine is chlorogenic acid (CGA). It is one of the most readily available phytochemicals that can be isolated from the leaves and fruits of plants, such as coffee beans (Coffea arabica L.), apples (Malus spp.), artichoke (Cynara cardunculus L.), carrots (Daucus carota L.), betel (Piper betle L.), burdock (Arctium spp.), etc. Despite its low oral bioavailability (about 33%), CGA has drawn considerable attention due to its wide range of biological activities and numerous molecular targets. Several studies have reported that the antioxidant and anti-inflammatory potentials of CGA mainly account for its broad-spectrum pharmacological attributes. CGA has been implicated in exerting a beneficial role against dysbiosis by encouraging the growth of beneficial GUT microbes. At the biochemical level, its therapeutic action is mediated by free radical scavenging efficacy, modulation of glucose and lipid metabolism, down-regulation of pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), IL-1β, and interferon-gamma (IFN-γ), upregulation of nuclear factor erythroid 2-related factor 2 (Nrf-2), and inhibition of the activity of nuclear factor- κβ (NF-κβ), thus helping in the management of diabetes, cardiovascular diseases, neurodegenerative disorders, cancer, hypertension etc. This review highlights the natural sources of CGA, its bioavailability, metabolism, pharmacotherapeutic potential, and underlying mechanisms of action for the clinical usefulness of CGA in the management of health disorders.

Pharmacological Activities of the Genus Passiflora (Passifloraceae): A Patent Review

Background: Passiflora L. is a genus belonging to the Passifloraceae family, with many species widely used in folk medicine and several pharmacological activities described in the scientific literature, being a major target for the development of new therapeutic products. Studies have identified several bioactive compounds in their composition as responsible for these activities, mainly C-glycoside flavonoids.

Objective: The aim of this study was to carry out a review of patents related to the genus and its application in several pharmacological activities, important for the development of new drugs and formulations.

Methods: The search was carried out in 5 specialized databases, INPI, EPO, WIPO, Latipat and Derwent, using the term ‘Passiflora’ combined with ‘A61K and A61P', subclasses of section A of the International Patent Classification (IPC), which are destined to medical, dental or hygienic purposes, and therapeutic activity of chemical compounds or medicinal preparation, respectively.

Results: 1,198 patents citing the genus in the title or abstract have been found, 508 being duplicates. After exclusion and inclusion criteria, 23 patents written in English, Portuguese and Spanish were selected, which demonstrated biological assays in vivo with species of Passiflora as the only active constituent or incorporated in formulations with other compounds.

Conclusion: The findings of this search showed growing interest in research and industrial areas in the pharmaceutical development with species of Passiflora, suggesting that the different bioactive compounds present in the genus can be considered as an important tool for the development of new effective and safe products with pharmacological potential.

The Role of NF-κB in Myocardial Ischemia/Reperfusion Injury

Acute myocardial infarction (AMI) is a threat to human life and physical health worldwide. Timely reperfusion is very important to limit infarct size and protect ischemic myocardium. Unfortunately, it has also caused severer myocardial damage, which is called “myocardial ischemia/ reperfusion injury (MIRI)”. There is no effective clinical treatment for it. Over the past two decades, biological studies of NF-κB have improved the understanding of MIRI. Nuclear Factor-κB (NF-κB) is a major transcription factor associated with cardiovascular health and disease. It is involved in the release of pro-inflammatory factors and apoptosis of cardiomyocytes. Recent studies have shown that inhibition of NF-κB plays a protective role in acute hypoxia and reperfusion injury. Here we review the molecular regulation of NF-κB in MIRI, better understanding of NF-κB signaling mechanisms related to inflammation and crosstalk with endogenous small molecules. We hope this review will aid in improving therapeutic approaches to clinical diagnosing. This review provides evidence for the role of NF-κB in MIRI and supports its use as a therapeutic target.

Dysregulation of SIRT-1 Signaling in Multiple Sclerosis and Neuroimmune Disorders: A Systematic Review of SIRTUIN Activators as Potential Immunomodulators and their Influences on other Dysfunctions

Immune dysregulation, neuronal inflammation, and oligodendrocyte degradation are key causes for autoimmune disorders like multiple sclerosis (MS) and various other immune dysregulated neurodegenerative complications responsible for CNS-mediated immune responses. Sirtuin (SIRT-1) is a nicotinamide adenosine dinucleotide (NAD)-dependent transcriptional protein that deacetylases and removes acetyl groups from its transcription factors like P53, FOXO, NF-Κb, PGC-1α. SIRT-1 mediates a wide range of physiological functions, including gene transcription, metabolism, neuronal apoptosis, and glucose production. SIRT-1 dysregulation targets transcription factors, and other molecular alterations such as gene expression modification influence neuronal plasticity, inhibit Th17 cells, and interleukin-1β can aggravate brain diseases. Preclinical and clinical findings show that the upregulation of SIRT-1 reduces autoimmunity, neurodegeneration, and neuroexcitation. Even though drugs are being developed for symptomatic therapies in clinical trials, there are particular pharmacological implications for improving post-operative conditions in neurodegenerative patients where intensive care is required. Understanding the SIRT-1 signaling and identifying immune-mediated neuron deterioration can detect major therapeutic interventions that could prevent neuro complications. Thus, in the current review, we have addressed the manifestations of disease by the downregulation of SIRT-1 that could potentially cause MS and other neurodegenerative disorders and provided data on existing available and effective drug therapies and disease management strategies.

Relationship between Augmentation Index and Wall Thickening Fraction during Hypotension in an Animal Model of Myocardial Ischemia-Reperfusion and Heart Failure

Aims: Non-invasive indices to evaluate left ventricular changes during ischemic heart failure are needed to quantify the myocardial impairment and the effectiveness of therapeutic manoeuvres. The aims of this work were to calculate the Wall Thickening Fraction (WTF) and the Augmentation Index (AIx) and to assess the relationship between WTF and AIx using data obtained from an animal model with heart failure followed by a myocardial ischemia stage and a reperfusion stage.

Methods: Nine Corriedale sheep that had been monitored for 10 minutes during a basal stage underwent 5-minute myocardial ischemia, followed by 60-minute reperfusion. Seven of them were subjected to an induced heart failure through an overdose of halothane, two of which were treated with intra-aortic counterpulsation during the reperfusion stage. The remaining two animals were monitored during their ischemia-reperfusion stage.

Results: Data obtained in the 5 animals suffering from heart failure followed by myocardial ischemia showed that: a) heart failure induction determined decrease in cardiac output, cardiac index and systolic and diastolic aortic pressure (AoP) with respect to their basal values (p<0.05), b) myocardial ischemia decreased the WTF compared with basal and induced heart failure values (p<0.05), c) during the reperfusion stage accompanied by induced heart failure, WTF increased with respect to values observed during the ischemia induction stage (p<0.05); nevertheless, basal values were not recovered after reperfusion (p<0.05). During this 60-minute stage, systolic and diastolic AoP values were lower (p<0.05) than those at the basal stage.

Conclusion: AIx and WTF values calculated from synchronically recorded values of aortic pressure and left ventricular wall thickness during the reperfusion stage in all animals (n = 9) showed a negative correlation (p<0.05). Analysed data provided evidence of a negative relationship between a left ventricular index of myocardial function and an arterial index obtained from AoP waves.

The Protective of Baicalin on Myocardial Ischemia-Reperfusion Injury

Background: The aim of this study was to explore the inhibitory effect of baicalin on myocardial apoptosis induced by Ischemia-Reperfusion (I/R).

Methods: Sprague Dawley rats' heart and myocardial cells I/R model were established in vivo and vitro, then 100 mg/kg and 10 μmol/l baicalin were administrated, respectively. The experiment was randomly divided into 4 groups (n=10): Control; I/R; IR+DMEM; and I/R+baicalin groups. Postoperation, the Left Ventricular (LV) End-Diastolic Pressure (LVEDP), the maximum velocity of LV contraction (dP/dtmax) and the maximum velocity of LV diastole (dP/dtmin) were recorded by the transthoracic echocardiography; the myocardial apoptosis percentage was analyzed by Annexin VFITC/ PI and TUNEL staining, and the apoptosis gene and protein were detected by RT-PCR and western blot. Furthermore, the protein expression of the calcium-sensing receptor (CaSR) and ERK1/2 phosphorylation were observed by western blot and Fura-2-acetoxymethyl ester. Moreover, primary rats’ cardiomyocytes were cultured and ERK1/2 specific inhibitor PD98059 was added to the culture medium. The cell survival rate, vitality and apoptosis were detected by MTT, lactate dehydrogenase (LDH) and TUNEL staining assay Kit, respectively.

Results: Our present study showed that baicalin significantly improved LV hemodynamic parameters and myocardial apoptosis in myocardial I/R injury rats. Furthermore, we found that baicalin could down-regulate the protein expression of CaSR, but up-regulate the protein expression of ERK1/2. Furthermore, when the cells were pretreated with ERK1/2 inhibitor PD98059, the cells survival rate significantly decreased, but LDH activity and apoptosis significantly increased. The results indicated that the effect of baicalin on myocardial I/R injury could be inhibited by ERK1/2 inhibitor.

Conclusion: In conclusion, our data suggests that baicalin attenuates I/R-induced myocardial injury maybe through the suppression of the CaSR/ERK1/2 signaling pathway.

The Advances on the Protective Effects of Ginsenosides on Myocardial Ischemia and Ischemia-Reperfusion Injury

Ginseng is a traditional medicine with a complex chemical composition, wide bioactivity and unique pharmacological action. Many studies have confirmed that ginsenosides are the active ingredients of ginseng, and ginsenosides have always been the focus of different researchers. With the development of modern separation and analysis technology, more than 150 kinds of ginsenosides have been isolated. The ginsenosides Rb1, Rb2, Rc, Rg1 and Re account for more than 80% of total ginsenosides, and other saponins, such as Rd, Rg3 and Rh2, which are minor constituents, accounting for only a small portion of the total amount. In recent years, ginsenosides have been found to possess strong pharmacological activities, such as antioxidation, clearing of oxygen free radicals, reducing calcium overload and anti-apoptosis. Ginsenosides play a protective role in ischemia-reperfusion injury. This paper reviews the protective effects of ginsenosides on myocardial ischemia and ischemiareperfusion injury.

Oxidative Stress-Induced Brain Damage Triggered by Voluntary Ethanol Consumption during Adolescence: A Potential Target for Neuroprotection?

Alcohol consumption, in particular ethanol (EtOH), typically begins in human adolescence, often in a “binge like” manner. However, although EtOH abuse has a high prevalence at this stage, the effects of exposure during adolescence have been less explored than prenatal or adult age exposure.

Several authors have reported that EtOH intake during specific periods of development might induce brain damage. Although the mechanisms are poorly understood, it has been postulated that oxidative stress may play a role. In fact, some of these studies revealed a decrease in brain antioxidant enzymes’ level and/or an increase in reactive oxygen species (ROS) production. Nevertheless, although existing literature shows a number of studies in which ROS were measured in developing animals, fewer reported the measurement of ROS levels after EtOH exposure in adolescence. Importantly, neuroprotective agents aimed to these potential targets may be relevant tools useful to reduce EtOH-induced neurodegeneration, restore cognitive function and improve treatment outcomes for alcohol use disorders (AUDs).

The present paper reviews significant evidences about the mechanisms involved in EtOH-induced brain damage, as well as the effect of different potential neuroprotectants that have shown to be able to prevent EtOH-induced oxidative stress. A selective inhibitor of the endocannabinoid anandamide metabolism, a flavonol present in different fruits (quercetin), an antibiotic with known neuroprotective properties (minocycline), a SOD/catalase mimetic, a potent antioxidant and anti-inflammatory molecule (resveratrol), a powerful ROS scavenger (melatonin), an isoquinoline alkaloid (berberine), are some of the therapeutic strategies that could have some clinical relevance in the treatment of AUDs. As most of these works were performed in adult animal models and using EtOH-forced paradigms, the finding of neuroprotective tools that could be effective in adolescent animal models of voluntary EtOH intake should be encouraged.

Impaired Myocardial MIF/AMPK Activation Aggravates Myocardial Ischemia Reperfusion Injury in High-Fat Diet-Induced Obesity

Background: Obese patients are more sensitive to myocardial ischemia, which has been linked with high mortality rates. The following study investigates the effects of impaired macrophage Migration Inhibitory Factor (MIF)/AMP-Activated Protein Kinase (AMPK) activation on increased susceptibility to myocardial ischemia/reperfusion (I/R) in high-fat diet-induced obesity.

Methods: Male C57BL/6J mice were fed with a normal diet (10% kcal as fat, lean group) or a high-fat diet (60kcal as fat, obese group) for 12 consecutive weeks. To detect the MIF expression and AMPK activation in response to I/R in isolated hearts from lean and obese mice, myocardial samples were collected from left ventricular areas at different time points. To determine whether MIF supplementation is protective against I/R injury, recombined MIF (10 ng/mL) was applied before ischemia. Myocardial infarct size was estimated by triphenyltetrazolium staining. Western blot was used to detect myocardial MIF expression, AMPK activation and membrane glucose transporter 4 (Glut4) expression.

Results: The expression of MIF was remarkably higher in obese group compared to lean group. Ischemia increased myocardial MIF expression and phosphorylation of AMPK in lean mice, whereas it had no significant effect on obese mice. Furthermore, administration of recombinant MIF increased ischemic AMPK activation and membrane Glut4 expression in both lean and obese mice, while it reduced the infarct size in lean mice only.

Conclusion: An impaired MIF/AMPK activation response and consequent reduced membrane Glut4 expression may play an important role in increasing myocardial susceptibility to I/R in obesity.

Neuroprotective Strategies for Neurological Disorders by Natural Products: An update

Nature has bestowed mankind with surplus resources (natural products) on land and water. Natural products have a significant role in the prevention of disease and boosting of health in humans and animals. These natural products have been experimentally documented to possess various biological properties such as antioxidant, anti-inflammatory and anti-apoptotic activities. In vitro and in vivo studies have further established the usefulness of natural products in various preclinical models of neurodegenerative disorders. Natural products include phytoconstituents, like polyphenolic antioxidants, found in herbs, fruits, nuts, vegetables and also in marine and freshwater flora. These phytoconstituents may potentially suppress neurodegeneration and improve memory as well as cognitive functions of the brain. Also, they are known to play a pivotal role in the prevention and cure of different neurodegenerative diseases, such as Alzheimer’s disease, epilepsy, Parkinson’s disease and other neuronal disorders. The large-scale neuro-pharmacological activities of natural products have been documented due to the result of either the inhibition of inflammatory processes, or the up-regulation of various cell survival proteins or a combination of both. Due to the scarcity of human studies on neuroprotective effects of natural products, this review focuses on the various established activities of natural products in in vitro and in vivo preclinical models, and their potential neuro-therapeutic applications using the available knowledge in the literature.

Curcuminoids and Novel Opportunities for the Treatment of Alzheimer's Disease: Which Molecules are Actually Effective?

Background: Millions of people worldwide are suffering from Alzheimer's disease (AD), and there are only symptomatic treatments available for this disease. Thus, there is a great need to identify drugs capable of arresting or reversing AD. Constituents of the spice turmeric, in particular, curcuminoids, seem to be very promising, as evident from in vitro experiments and tests using animal models of AD. However, most of the clinical trials did not reveal any beneficial effects of curcuminoids in the treatment of AD. These controversies, including conflicting results of clinical trials, are thought to be related to bioavailability of curcuminoids, which is low unless it is enhanced by developing a special formulation. However, there is growing evidence suggesting that other reasons may be of even greater importance, but these avenues are less explored.

Objective: Review relevant literature, and analyze potential reasons for the controversial results.

Methodology: Recent in vitro and preclinical studies; clinical trials (without a limiting period) were searched in PubMed and Google Scholar.

Results: While recent in vitro and preclinical studies confirm the therapeutic potential of curcuminoids in the treatment of AD and cognitive dysfunctions, results of corresponding clinical trials remain rather controversial.

Conclusion: The controversial results obtained in the clinical trials may be in part due to particularities of the curcuminoid formulations other than bioavailability. Namely, it seems likely that the various formulations differ in terms of their minor turmeric constituent(s). We hypothesize that these distinctions may be of key importance for efficacy of the particular formulation in clinical trials. A testable approach addressing this hypothesis is suggested.

Connexin43 and Myocardial Ischemia-Reperfusion Injury

Background: Recently, the treatment and prevention of ischemic cardiomyopathy is one of the emerging research topics in the cardiovascular field. Gap junction is the basic structure of cardiac electrophysiology. Connexin is the basic unit of gap junctions. Connexin43(CX43) is the most abundant member of Cx family in the heart, the normal expression of Cx43 is important for heart development, electrically coupled cardiomyocytes activities and coordination of myocardial function. The connection between Cx43 and myocardial ischemia/reperfusion or reperfusion injury has become the focus of current research.

Methods: We undertook a structured search of bibliographic database for peer-reviewed research literature using a focused review question and inclusion/exclusion criteria. The quality of retrieved papers was appraised using standard tools. The characteristics of screened papers were described, and a deductive qualitative content analysis methodology was applied to analyze the interventions and findings of included studies using a conceptual framework.

Results: Twenty-one papers were included in the review, eight papers outlined the relationship of Cx43 and reperfusion arrhythmias. Eight papers pointed out the effect on the infarct size of Cx43.

Conclusion: The findings of this review confirm that Cx43 is the most abundant member of Cx family in the heart and is vital for myocardial protection during ischemia/reperfusion process and for ischemia/reperfusion injury. Many of its mechanism are still not very clear and require future research in the future.

Combination Therapy for Multi-Target Manipulation of Secondary Brain Injury Mechanisms

Traumatic brain injury (TBI) is a major healthcare problem that affects millions of people worldwide. Despite advances in understanding and developing preventative and treatment strategies using preclinical animal models, clinical trials to date have failed, and a 'magic bullet’ for effectively treating TBI-induced damage does not exist. Thus, novel pharmacological strategies to effectively manipulate the complex and heterogeneous pathophysiology of secondary injury mechanisms are needed. Given that goal, this paper discusses the relevance and advantages of combination therapies (COMTs) for ‘multi-target manipulation’ of the secondary injury cascade by administering multiple drugs to achieve an optimal therapeutic window of opportunity (e.g., temporally broad window) and compares these regimens to monotherapies that manipulate a single target with a single drug at a given time. Furthermore, we posit that integrated mechanistic multiscale models that combine primary injury biomechanics, secondary injury mechanobiology/neurobiology, physiology, pharmacology and mathematical programming techniques could account for vast differences in the biological space and time scales and help to accelerate drug development, to optimize pharmacological COMT protocols and to improve treatment outcomes.

High Resolution M-mode Evaluation of Jugular Vein Valves in Patients with Neurological and Neurosensory Disorders

Background: High prevalence of valve absence was found in the internal jugular vein (IJV) of healthy volunteers by means of M-mode high-resolution Echo Colour Doppler (ECD). However, the prevalence of valve in neurovascular disorders linked to Chronic Cerebrospinal Venous Insufficiency (CCSVI) is still unknown.

Methods: A cohort of 83 Healthy Controls (HC), 71 Multiple Sclerosis (MS), 99 Inner Ear Disorders (IED) underwent ECD investigation of the IJV valve, including M-mode evaluation and related hemodynamics. The primary outcome measure was characterization of valve presence, morphology and motility, whereas the secondary outcome was the rate of flow alteration.

Results: Bilateral valve presence was found in 38% of HC, 58% of MS and 25% of IED, whereas, bilateral valve absence was recorded in 16% of HC, 10% of MS and 31% of IED (p<0.003). Bicuspid morphology was more prevalent in HC 56%, while monocusp was more prevalent in patients: 75% MS and 57% IED (p<0.0001). The main finding was the presence of mobile valve leaflets in 98% of HC, contrarily fixed valve leaflets were recorded in 82% of MS and in 41% of IED, p< 0.0001.

Finally, by stratifying the entire cohort according to the presence of mobile and not mobile valve leaflets, normal monodirectional and phasic flow were commonly found in the mobile leaflets subgroup, p<0.0001.

Conclusion: In patients with miscellaneous neurological disorders, a significant higher rate of defective valves was found with respect to HC. The latter condition is strongly associated to brain outflow abnormalities described in CCSVI condition.

Cardioprotective Utility of Urocortin in Myocardial Ischemia- Reperfusion Injury: Where do We Stand?

Background: There has been a constant pursuit for development of newer therapies which can contribute to the relatively nascent field of cardioprotection in the setting of myocardial ischemiareperfusion injury. One novel cardioprotective agent among others, that has shown promising results in the limited number of research studies undertaken till now, is Urocortin. Urocortins are peptides belonging to the Corticotropin-Releasing Hormone family.

Results: Acting through a variety of downstream mechanisms, urocortin has been shown to alter cellular metabolism and modulate the mechanism of cell death occurring as a result of ischemia-reperfusion injury. New evidence continues to accumulate in support of urocortin’s beneficial role in cytoprotection.

Conclusion: We present here an updated review largely focused on the various mechanisms through which urocortin alters cellular metabolism, and discuss the clinical potential of urocortin’s cardioprotective ability in myocardial ischemia-reperfusion injury.

Epigenetic Regulation of Memory-Therapeutic Potential for Disorders

Background: Memory is a vital function which declines in different physiological and pathological conditions such as aging and neurodegenerative diseases. Research in the past has reported that memory formation and consolidation require the precise expression of synaptic plasticity genes. However, little is known about the regulation of these genes. Epigenetic modification is now a well established mechanism that regulates synaptic plasticity genes and neuronal functions including memory. Therefore, we have reviewed the epigenetic regulation of memory and its therapeutic potential for memory dysfunction during aging and neurological disorders.

Method: Research reports and online contents relevant to epigenetic regulation of memory during physiological and pathological conditions have been compiled and discussed.

Results: Epigenetic modifications include mainly DNA methylation and hydroxymethylation, histone acetylation and methylation which involve chromatin modifying enzymes. These epigenetic marks change during memory formation and impairment due to dementia, aging and neurodegeneration. As the epigenetic modifications are reversible, they can be modulated by enzyme inhibitors leading to the recovery of memory.

Conclusion: Epigenetic modifications could be exploited as a potential therapeutic target to recover memory disorders during aging and pathological conditions.

New Pharmacological Approaches to the Prevention of Myocardial Ischemia- Reperfusion Injury

Background: Early reperfusion of the blocked vessel is critical to restore the blood flow to the ischemic myocardium to salvage myocardial tissue and improve clinical outcome. This reperfusion strategy after a period of ischemia, however, may elicit further myocardial damage named myocardial reperfusion injury. The manifestations of reperfusion injury include arrhythmias, myocardial stunning and micro-vascular dysfunction, in addition to significant cardiomyocyte death. It is suggested that an overproduction of reactive oxygen species, intracellular calcium overload and inflammatory cell infiltration are the most important features of myocardial ischemia-reperfusion injury.

Objective: In this review, various pharmacological interventions to treat myocardial reperfusion injury including the antioxidant flavonols, hydrogen sulfide, adenosine, opioids, incretin-based therapies and cyclosporin A which targets the mitochondrial permeability transition pore are discussed.

Conclusion: The processes involved in reperfusion injury might provide targets for improved outcomes after myocardial infarction but thus far that aim has not been met in the clinic.

Possible Targets of Herbals for Type 3 Diabetes: A Review

There is substantial evidence for the formation of Aβ and their conversion into toxic species under hyperglycemic condition. So, we can say that brain is one of the most important sites for diabetic end organ damage and AZ can be considered as a type of Diabetes. Till date we don’t have proper therapy for successful prevention of neuronal cell death in neurodegenerative diseases and research focuses to bring drugs that can either slow down disease progression or provide prophylaxis. However, Ayurveda that has numerous plants which can execute amazing and outstanding properties with (few) actions of herbs that are quite new to the conventional medicine. Polyphenolic compounds, found in various types of plant parts, that are antioxidant by nature having useful prophylactic properties for the treatment of excitotoxicity and oxidative cell death. Plants become source material for the development of drugs, as herbs have recently become attractive for targeting different pathologies as health-beneficial foods (physiologically functional foods). As an addition to various potent reviews that provided the therapeutic effect/efficacy information about various herbals as better neuro modulators, herein we have given up to date information of various phytoconstituents, polyherbal formulations and extracts which were found effective in the treatment of AZ. Although there are several herbals that have been proved to increase cognitive abilities, here we mentioned the herbals that were tested against various AZ insults.

Cannabinoids and Psychosis

There is growing interest in the relationship between cannabis and psychosis. The link between cannabis use and psychosis comprises three distinct relationships: acute psychosis associated with cannabis intoxication, acute psychosis that lasts beyond the period of acute intoxication, and persistent psychosis not time-locked to exposure. Experimental studies reveal that cannabis, tetrahydrocannabinol (THC) and synthetic cannabinoids reliably produce transient positive, negative, and cognitive symptoms in healthy volunteers. Case-studies indicate that cannabinoids can induce acute psychosis which lasts beyond the period of acute intoxication and persisting as long as a month. Exposure to cannabis in adolescence is associated with an increased risk for later psychotic disorder in adulthood; this association is consistent, somewhat specific, shows a dose-response, and is biologically plausible. The link between cannabinoids and psychosis is greater with earlier age of exposure to cannabinoids, childhood abuse and genetic vulnerability. However, cannabinoids are neither necessary nor sufficient to cause a persistent psychotic disorder. More likely cannabinoids are a ‘component cause’ interacting with other known (family history) and unknown factors to result in psychosis outcomes. While more research is needed to better understand the relationship between cannabinoid use and psychosis, and the neural underpinnings of this link, clinicians should be mindful of the potential risk of psychosis especially in vulnerable populations, including adolescents and those with a psychosis diathesis.

α-Melanocyte Stimulating Hormone as a Potential Therapy for Alzheimer's Disease

Background: Alzheimer's disease (AD) is characterized by accumulation and aggregation of beta-amyloid peptide, neurofibrillary tangles of hyperphosphorylated tau, neuroinflammation, synaptic degeneration and eventual neuronal cell loss. Current treatment options for AD provide temporary symptomatic relief in a subset of patients. These drugs include cholinesterase inhibitors that improve cholinergic innervation such as rivastigmine, donepezil and galatamine. In addition, memantine, a Nmethyl- D-aspartate antagonist, is used to treat moderate to severe AD by reducing excitotoxicity. It has been proposed that increased excitation and decreased inhibition lead to aberrant excitatory neuronal activity and cognitive deficits in AD.

Methods: We undertook a search of the literature using bibliographic databases to identify publications that were related to neuronal activity in Alzheimer's disease. We further delineated the publications to determine inclusion/exclusion criteria based on relevance to increased excitation or decreased inhibition of neuronal networks in both human patients and rodent models. The final criteria related to the potential use of α-Melanocyte stimulating hormone (α-MSH) as a potential treatment strategy for Alzheimer's disease. These data were utilized to obtain the content of this review.

Results: We identified 156 peer-reviewed publications that met our criteria and describe the findings here. Rodent models of AD and ageing both exhibit cognitive deficits and loss of inhibitory GABAerigc interneurons. α-Melanocyte stimulating hormone is a neuropeptide that is down-regulated in the brain and cerebrospinal fluid of AD patients. α-MSH has many functions in the central nervous system including neuroprotective and anti-inflammatory effects that target multiple aspects of the AD pathology. α-MSH treatment promoted the survival of GABAergic interneurons in the hippocampus and improved spatial memory as well as alterations in anxiety in a mouse model of AD. The somatostatin expressing subpopulation of GABAergic interneurons are particularly preserved by α-MSH treatment. Somatostatin has been implicated in hippocampal-dependent cognitive tasks. Somatostatin-expressing interneurons have also been shown to play an important role in maintaining excitatory-inhibitory balance. α-MSH preserved GABAergic interneurons and by preventing the loss of the somatostatin subpopulation, it improved cognitive function.

Conclusion: α-MSH is a novel candidate for the treatment of AD but its therapeutic potential in AD patients remains to be investigated.

‘Non-Criteria’ Neurologic Manifestations of Antiphospholipid Syndrome: A Hidden Kingdom to be Discovered

Neurological manifestations or disorders associated with the central nervous system are among the most common and important clinical characteristics of antiphospholipid syndrome (APS). Although in the most recently updated (2006) APS classification criteria, the neurological manifestations encompass only transient ischemic attack and stroke, diverse ‘non-criteria’ neurological disorders or manifestations (i.e., headache, migraine, bipolar disorder, transverse myelitis, dementia, chorea, epileptic seizures, multiple sclerosis, psychosis, cognitive impairment, Tourette’s syndrome, parkinsonism, dystonia, transient global amnesia, obsessive compulsive disorder and leukoencephalopathy) have been observed in APS patients. To date, the underlying mechanisms responsible for these abnormal neurological manifestations in APS remain unclear. In vivo experiments and human observational studies indicate the involvement of thrombotic events and/or high titers of antiphospholipid antibodies in the neuro-pathogenic cascade of APS. Although different types of neurologic manifestations in APS patients have successfully been treated with therapies involving anti-thrombotic regimens (i.e., anticoagulants and/or platelet antiaggregants), antineuralgic drugs (i.e., antidepressants, antipsychotics and antiepileptics) and immunosuppressive drugs alone or in combination, evidence-based guidelines for the management of the neurologic manifestations of APS remain unavailable. Therefore, further experimental, clinical and retrospective studies with larger patient cohorts are warranted to elucidate the pathogenic linkage between APS and the central nervous system in addition to randomized controlled trials to facilitate the discovery of appropriate medications for the ‘non-criteria’ neurologic manifestations of APS.

Cognitive Function and Heart Failure: The Role of the Adrenergic System

Background: Heart Failure (HF) and cognitive impairment (CI) represent two high incident diseases worldwide, with extremely elevated mortality and morbidity rates. Their prevalence is expected to further increase in the next years due to the aging population, thus they pose enormous clinical, social and economic challenges. Sympathetic nervous system hyperactivity is known to play a pivotal role in HF pathophysiology and progression. In fact, increased cardiac and circulating catecholamine levels are responsible for several molecular and structural abnormalities with detrimental effects on the failing heart. The proof of this latter concept is represented by the clinical success of -Blocker therapy that is able to attenuate HF-related morbidity and mortality. Recently, adrenergic system alterations have been implied also in the pathogenesis of CI and dementia opening the window for new fascinating and promising therapeutic opportunities.

Objective: Assess the state of the art on the relationship between cognitive impairment and heart failure.

Method: In the present manuscript, we propose an updated review of literature and patent on the role of sympathetic nervous system derangement in the pathogenesis of HF and CI.

Conclusion: We have discussed recent findings allowing the identification of new molecular targets that hopefully will contribute to the generation of effective therapeutic strategies for HF and dementia.

In this article, the patents US20100048479, US7060871, WO2006052857, US7351401, US5721243, WO1994009155, US5449604, WO1999058981, US5985581, EP2319511, EP2377534, EP2650303, WO2006004939, WO2010132128 and EP1779858 are summarized.

Endocannabinoid System in Neurological Disorders

Background: Several studies support the evidence that the endocannabinoid system and cannabimimetic drugs might have therapeutic potential in numerous pathologies. These pathologies range from neurological disorders, atherosclerosis, stroke, cancer to obesity/metabolic syndrome and others.

Methods: In this paper we review the endocannabinoid system signaling and its alteration in neurodegenerative disorders like multiple sclerosis, Alzheimer’s disease, Parkinson’s disease and Huntington’s disease and discuss the main findings about the use of cannabinoids in the therapy of these pathologies.

Results: Despite different etiologies, neurodegenerative disorders exhibit similar mechanisms like neuro-inflammation, excitotoxicity, deregulation of intercellular communication, mitochondrial dysfunction and disruption of brain tissue homeostasis. Current treatments ameliorate the symptoms but are not curative. Interfering with the endocannabinoid signaling might be a valid therapeutic option in neuro-degeneration. To this aim, pharmacological intervention to modulate the endocannabinoid system and the use of natural and synthetic cannabimimetic drugs have been assessed. CB1 and CB2 receptor signaling contributes to the control of Ca2+ homeostasis, trophic support, mitochondrial activity, and inflammatory conditions.

Conclusion: Several studies and patents suggest that the endocannabinoid system has neuro-protective properties and might be a target in neurodegenerative diseases.

Pharmacological Properties and Therapeutic Potential of Naringenin: A Citrus Flavonoid of Pharmaceutical Promise

Naringenin chemically known as 5,7-dihydroxy-2-(4-hydroxyphenyl)chroman-4-one is a common dietary polyphenolic constituent of the citrus fruits. It has received considerable attention for pharmaceutical and nutritional development due to potent pharmacological activities and therapeutic potential. Accruing evidence from both in vitro and in vivo studies have unraveled numerous biological targets along with complex underlying mechanisms suggesting possible therapeutic applications of naringenin in various neurological, cardiovascular, gastrointestinal, rheumatological, metabolic and malignant disorders. Functionally, this ameliorative effect of naringenin is primarily attributed to its antiinflammatory (via inhibiting recruitment of cytokines and inflammatory transcription factors) and anti-oxidant (via scavenging of free radicals, bolstering of endogenous antioxidant defense system and metal ion chelation) effects. The present article provides a comprehensive review of the various studies that have evaluated the therapeutic potential of naringenin and its actions at the molecular level. It also summarizes the pharmacokinetic data and issues and challenges involved in pharmaceutical development and suggest that it may be a potential agent for further exploration as well as may be useful as a dietary adjunct in treatment of various human ailments.

Prognostic Significance of Asymptomatic Myocardial Ischemia in Women vs. Men

Background: Silent myocardial ischemia is a recognized but suboptimally studied condition in patients with and without known coronary artery disease. Limited work has focused on the association between silent myocardial ischemia and future prognosis however the majority of these analyses have focused mostly on male cohorts. As signs and symptoms of myocardial ischemia are known to be different in women, it is important to discuss and highlight any differences in association between silent myocardial ischemia and adverse cardiovascular outcomes based on gender. Methods: The aim of this review is to summarize the current literature available discussing silent myocardial ischemia and potential gender differences. We searched English language studies on PUBMED and the Cochrane Database of Systematic Reviews from the database start dates to November 2015. Conclusion: As data on the presence of silent myocardial ischemia in women is limited, whether a differential association based on gender between this condition and cardiovascular prognosis remains unknown. Future studies should target women especially those without epicardial coronary disease and suspected coronary microvascular dysfunction.

Targeting the Cholinergic System for Neuroprotection and/or Enhancement of Functional Recovery Following Neurotrauma

Development of novel pharmacotherapies for the treatment of traumatic injury to the nervous system has been ongoing for over 40 years. Despite many promising compounds discovered using animal models, no treatments have successfully translated into the clinic. The central dogma in this field is that brain trauma initiates a complex chain of biochemical events leading to secondary brain damage and sustained neurological deficits. The delayed secondary brain injury is likely to result from multiple insults including oxidative stress, mitochondrial dysfunction, breakdown of the blood brain barrier, dysregulated release of glutamate, pro-inflammatory cytokines, and other mediators. However, therapies targeting these systems have generally met with failure in clinical trials. The purpose of this review is to summarize the models used for preclinical neurotrauma research, provide a brief overview of previous failed clinical trials in head and spinal cord injury, and finally, to review involvement of the cholinergic system and discuss implications for future research. Possibilities and pitfalls of targeting the cholinergic system for neuroprotection and/or enhancement of functional recovery are also discussed.

Novel Therapeutic Strategies for Dementia

Dementia represents a major problem of health and disability, with a relevant economic impact on our society. Despite important advances in pathogenesis, diagnosis and treatment, its primary causes still remain elusive, accurate biomarkers are not well characterized, and the available pharmacological treatments are not cost-effective. Alzheimer disease (AD), the most prevalent form of dementia, is a polygenic/multifactorial/complex disorder in which hundreds of defective genes distributed across the human genome may contribute to its pathogenesis. Diverse environmental factors, cerebrovascular dysfunction, and epigenetic phenomena, together with structural and functional genomic dysfunctions lead to amyloid deposition, neurofibrillary tangle formation and premature neuronal death, the major neuropathological hallmarks of AD.

For the past 20 years, over 1,000 different compounds have been studied as potential candidate drugs for the treatment of AD. About 50% of these substances are novel molecules obtained from natural sources. The candidate compounds can be classified according to their pharmacological properties and/or the AD-related pathogenic cascade to which they are addressed to halt disease progression. In addition to the Food and Drug Administration (FDA)-approved drugs since 1993 (tacrine, donepezil, rivastigmine, galantamine, memantine), most candidate strategies fall into 6 major categories: (i) novel cholinesterase inhibitors and neurotransmitter regulators, (ii) anti-amyloid beta (Aβ) treatments (amyloid-β protein precursor (APP) regulators, Aβ breakers, active and passive immunotherapy with vaccines and antibodies, β - and γ - secretase inhibitors or modulators), (iii) anti-tau treatments, (iv) pleiotropic products (most of them of natural origin), (v) epigenetic intervention, and (vi) combination therapies. The implementation of pharmacogenomic strategies will contribute to optimize drug development and therapeutics in AD and related disorders.

Biomarkers in Silent Traumatic Brain Injury

Traumatic brain injury (TBI) has been recognized among the leading causes of mortality and morbidity in young adults. Traditionally, the diagnosis of TBI has been based on neuroimaging. However, a significant portion of insulted patients appear to be apparently asymptomatic. As a result, more elaborate indices of silent TBI are required in order to immediately detect focal and diffuse asymptomatic TBI. Such valid indices will potentially increase the efficacy of therapeutic strategies in TBI patients.

In this review of the literature, we present novel circulating biomolecules, as potential biomarkers of silent TBI, like neurofilaments, Cleaved-Tau (C-Tau), Microtubule-Associated Protein 2 (MAP2), Neuron-Specific Enolase, S100B and ferritin. In addition to this, assessment of white matter abnormalities and white matter integrity by diffusion tensor imaging (DTI) have emerged as promising sensitive neuroimaging methods of silent TBI. An integrated research is needed to fully understand the interplay between all the aforementioned indices and DTI. The potential diagnostic, therapeutic and prognostic values of the all aforementioned indices will be analyzed in the proposed review.

GABAergic Pharmacotherapy in the Treatment of Motor Disorders of the Central Nervous System

Gamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the central nervous system, and diseases that associate a deficiency in GABA might benefit from GABAergic drugs.

Cerebellar Purkinje cells employ GABA as a neurotransmitter. Cortical cerebellar atrophy (CCA) shows Purkinje cell loss, and ataxia caused by it was alleviated by gabapentin and pregabalin. Thus, CCA is proposed as a model of selective deficiency in GABA in the cerebellum, which benefits clinically from administration of GABAergic drugs, in a manner similar in which levodopa improves motor manifestations in Parkinson’s disease. Other ataxias also benefited clinically from GABAergic drugs, as adult-onset GM2 gangliosidosis, olivopontocerebellar atrophy, cerebellar ataxia with hypogonadism, spinocerebellar ataxias 1, 2 and 6, and adult-onset ataxia-telangiectasia. Complex neurochemical diseases, as multiple-system atrophy, had ataxia worsened by GABAergic drugs. Various disorders with a deficiency in GABA content had their manifestations relieved by admistration of GABAergic drugs, as one patient with progressive encephalomyelitis with rigidity, whose muscular spasms were suppressed by a combination of gabapentin and tiagabine, and another with diaphragmatic myoclonus, who required gabapentin and tiagabine for symptomatic control. On the contrary, GABAergic drugs were not effective in cervical dystonia, amyotrophic lateral sclerosis, Parkinson’s disease and progressive supranuclear palsy, presumably because a deficiency in GABA is not an essential neurochemical abnormality in these diseases. Research aimed at identifying effective therapies to treat cerebellar ataxias and other motor disorders of the central nervous system is warranted. Meanwhile, therapeutic tests with GABAergic drugs might yield clinical improvement in these diseases.

Treatment Options in Alzheimer´s Disease: The GABA Story

Alzheimer’s disease (AD) is the most common form of dementia in the elderly. Research focused on identifying compounds that restore cognition and memory in AD patients is a very active investigational pursuit, but unfortunately, it has been only successful in terms of developing symptomatic treatments. Aβ deposition and neurofibrillary tangles along with neuron and synapse loss are associated with neurotransmitter dysfunction and have been recognized as hallmarks of AD. Furthermore, clinical and preclinical studies point to this neurotransmitter dysfunction as a main factor underlying both cognitive and neuropsychiatric symptoms of the illness.

Cholinergic deficit in AD prompted the use of cholinesterase inhibitors as the symptomatic treatment of cognitive decline in AD, however this therapeutic approach provides only modest benefit in the majority of patients. Hence, nowadays research is focused on investigating compounds that could restore cognition and memory in AD patients. GABA is the primary inhibitory neurotransmitter in the central nervous system and GABAergic neurons provide extensive innervation to cholinergic and glutamatergic neurons. It has been shown that dysfunction of the GABAergic system may contribute to cognitive impairment in humans. Significant reductions in GABA levels have been described in severe cases of AD, which could be underlying the behavioral and psychological symptoms of AD. This review examines the involvement of the GABAergic system in both cognitive and non-cognitive behavioural symptoms in AD, providing some pointers for rational drug development.

Anti-Alzheimer Therapeutic Drugs Targeting γ-Secretase

γ-secretase is a membrane-embedded aspartyl protease carrying out cleavage of more than 100 single transmembrane-spanning proteins, including APP, Notch, N-cadherin, etc. Its subunit, presenilin (PS) is the catalytic component, of which mutations are a major cause of early onset familial Alzheimer disease (FAD). These mutations lead to an increase in the production of the highly amyloidogenic Aβ42 isoform. Drugs aimed at γ-secretase are now considered to be promising therapeutic targets for AD. γ-secretase inhibitors (GSIs) were first introduced into clinical trials due to their efficacy in lowering Aβ production, but later were found to cause severe adverse events due to their blockage of the Notch signaling process. γ-secretase modulators (GSMs) were developed to modulate γ-secretase activity by selectively targeting Aβ42 reduction over the Notch pathway, which have been shown to have less side effects. Although clinical studies show that none of the GSIs or GSMs have been proven to be fully effective, they shed light on the physiological role of γ-secretase and PS in AD development. At the same time, natural products, due to their structural diversity and pleiotropic profile, can modulate γ-secretase activity in a dose-dependent manner, broadening our vision of drug development. With the structural information of γ-secretase released recently, we speculate there will be an explosion of γ-secretase modulators targeting not only the proteolysic center but also the interaction of its different components.

Atypical Neurotransmitters and the Neurobiology of Depression

Since the first report that the mechanism of action of antidepressants involves the facilitation of monoaminergic neurotransmission in the brain in the 1960s, the leading hypothesis about the neurobiology of depression has been the so called “monoaminergic hypothesis”. However, a growing body of evidence from the last two decades also supports important involvement of non-monoaminergic mechanisms in the neurobiology of depression and antidepressant action.

The discovery of nitric oxide (NO) and endocannabinoid signaling in the brain during the 1990s challenged the wellestablished criteria of classical neurotransmission. These transmitters are synthesized and released on demand by the postsynaptic neurons, and may act as a retrograde messenger on the presynaptic terminal, modulating neurotransmitter release. These unconventional signaling mechanisms and the important role as neural messengers have classified NO and endocannabinoids as atypical neurotransmitters. They are able to modulate neural signaling mediated by the main conventional neurotransmitters systems in the brain, including the monoaminergic, glutamatergic and GABAergic signaling systems.

This review aims at discussing the fundamental aspects of NO- and endocannabinoid-mediated signaling in the brain, and how they can be related to the neurobiology of depression. Both preclinical and clinical evidence supporting the involvement of these atypical neurotransmitters in the neurobiology of depression, and in the antidepressant effects are presented here. The evidence is discussed on basis of their ability to modulate different neurotransmitter systems in the brain, including monoaminergic and glutamatergic ones. A better comprehension of NO and endocannabinoid signaling mechanisms in the neurobiology depression could provide new avenues for the development of novel non-monoamine based antidepressants.

Impact of Jugular Vein Valve Function on Cerebral Venous Haemodynamics

We quantify the effect of internal-jugular vein function on intracranial venous haemodynamics, with particular attention paid to venous reflux and intracranial venous hypertension. Haemodynamics in the head and neck is quantified by computing the velocity, flow and pressure fields, and vessel cross-sectional area in all major arteries and veins. For the computations we use a global, closed-loop multi-scale mathematical model for the entire human circulation, recently developed by the first two authors. Validation of the model against in vitro and in vivo Magnetic Resonance Imaging (MRI) measurements have been reported elsewhere. Here, the circulation model is equipped with a sub-model for venous valves. For the study, in addition to a healthy control, we identify two venous-valve related conditions, namely valve incompetence and valve obstruction. A parametric study for subjects in the supine position is carried out for nine cases. It is found that valve function has a visible effect on intracranial venous haemodynamics, including dural sinuses and deep cerebral veins. In particular, valve obstruction causes venous reflux, redirection of flow and intracranial venous hypertension. The clinical implications of the findings are unknown, though they may relate to recent hypotheses linking some neurological conditions to extra-cranial venous anomalies.

microRNAs: Promising Biomarkers and Therapeutic Targets of Acute Myocardial Ischemia

microRNAs (miRNAs), small non-coding RNA molecules that act as negative regulators of gene expression, are involved in a wide range of biological functions and control several cellular processes. This review illustrates miRNA regulation and function in tissue response to acute ischemia, focusing on miRNA role in acute myocardial infarction and describing a subset of miRNAs de-regulated upon cardiac ischemia. These miRNAs may represent “master ischemic” miRNAs, playing a pathogenetic role in one of the different components of tissue response to ischemia. Moreover, circulating miRNAs correlated to myocardial infarction and examples of miRNA involvement in ischemic diseases different from cardiac ischemia are also discussed. The identification of specific miRNAs as key regulators of cell biology has opened new clinical avenues, and may allow new diagnostic and/or prognostic tools development, as much as innovative therapeutic strategies. Two paradigmatic reports, in which miRNAs have been targeted to improve cardiac function in pre-clinical models of myocardial infarction, are described in detail and confirmed the efficacy of these strategies.

Drainage of Cerebral Abscesses Prior to Valve Replacement in Stable Patients with Acute Left-Sided Infective Endocarditis

Despite the medical and surgical advancements in the treatment of patients with acute infective endocarditis (IE), neurologic complications remain problematic. They can arise through various mechanisms consisting of stroke or transient ischemic attack, cerebral hemorrhage, mycotic aneurysm, meningitis, cerebral abscess, or encephalopathy. Most complications occur early during the course of IE and are characteristic to left-sided pathology of native or prosthetic valves. We present a case of a 46 year old male patient who presented to our clinic with mitral valve IE caused by coagulase negative staphylococcus. Although under correct antibiotic treatment, he continued to be feverish and started to present unspecific neurological symptoms (amnesia, confusion, asthenia and general malaise). The cerebral magnetic resonance imaging (MRI) revealed multiple cerebral abscesses. Because the patient was hemodynamically stable we decided to address the cerebral abscess first and the cardiac lesion second. The patient made a full recovery after undergoing antibiotic treatment and surgical procedures of drainage of the cerebral abscess and mitral valve replacement. After reviewing the literature regarding the management of patients with IE and cerebral complications and based on this particular case, we conclude that in select cases of stable patients with cerebral abscess and IE, the neurological lesion should always be addressed first and cardiac surgery should be performed second.

Trauma Interventions using Mindfulness Based Extinction and Reconsolidation (TIMBER^©) as Monotherapy for Chronic PTSD: A Pilot Study

Objective: Despite recent advancements in treatments, prognosis for PTSD is still poor and there are limited therapeutic options. Because of feasibility and acceptability issues with many existing treatment options, this challenge is even more pronounced in adolescents with PTSD. The extinction-only based treatments including prolonged exposure therapy (PE) have significant limitations in terms of tolerability and efficacy.

Method: This paper presents an overview of Trauma Interventions using Mindfulness Based Extinction/Reconsolidation (TIMBER), a translational mindfulness based psychotherapy for PTSD, which was developed by the first author, and preliminary results of this treatment in four adolescent patients. The methodology of TIMBER integrates principles of mindfulness based graded exposure therapy with neurobiological understanding of trauma memories including the interplay between the memory extinction and memory reconsolidation mechanisms that lead to formation and maintenance of the trauma memories in a dynamic way. TIMBER uses combined extinction and reconsolidation approaches, whereby reappraisal and modification of the trauma experiences are done via cognitive-emotive restructuring. The technique employs cognitive-behavioral and standardized Yoga and meditation interventions to induce new learning. This combined and targeted approach prevents restoration or re-expression of the trauma memories and the associated reactivity that lie at the core of the dysfunctions in PTSD. TIMBER has been tested in adults, either alone or in combination with medications.

Results: All four patients remitted with respect to the symptoms of PTSD and associated dysfunction as measured clinically as well as based on their scores on PTSD specific rating scale. This improvement was maintained during follow-up of up to 8 months.

Conclusion: Efficacy of TIMBER is currently being evaluated in a double blind randomized controlled trial in adult patients with PTSD. In this paper, we present the version of the TIMBER applicable to adolescents suffering from PTSD. Although further replication in future studies is necessary before drawing definite conclusions, preliminary data on efficacy of TIMBER for treatment of PTSD are encouraging. Further study in larger samples is necessary to confirm its usefulness in adolescent patients with PTSD.

Fish Oil Prevents Oxidative Stress and Exerts Sustained Antiamnesic Effect After Global Cerebral Ischemia

Transient, global cerebral ischemia (TGCI) causes hippocampal/cortical damage and the persistent loss of welltrained, long-term memory (retrograde amnesia). Fish oil (FO), a rich source of omega-3 polyunsaturated fatty acids, abolishes such amnesia in the absence of neurohistological protection. The present study investigated whether FO prevents ischemia-induced oxidative stress and whether such an action contributes to the lasting effect of FO on memory recovery. In a first experiment, FO was administered for 4 days prior to ischemia, and antioxidant status was subsequently measured after 24 h of reperfusion. In another experiment, naive rats were trained in an eight-arm radial maze until they achieved asymptotic performance and then subjected to TGCI. One group of rats received FO as in the first experiment (i.e., 4 days prior to ischemia), whereas another group received FO for 4 days prior to ischemia plus 6 days postischemia. Retrograde memory performance was assessed 2-5 weeks after ischemia. TGCI depleted the level of antioxidant enzymes and increased the amount of protein carbonylation, indicating oxidative damage. Fish oil reversed oxidative damage to control levels. The same treatment that attenuated oxidative stress after 24 h of reperfusion also prevented retrograde amnesia assessed several weeks later. This antiamnesic effect afforded by short preischemia treatment was comparable to 10 days of treatment but not as consistent. These data indicate that an antioxidant action in the hyperacute phase of ischemia/reperfusion may contribute to the long-term, antiamnesic effect of FO.

Anesthetic Pharmacology and Perioperative Considerations for Heart Transplantation

From uncertain beginnings over four decades ago, heart transplantation is now the definitive therapy for end-stage heart failure. This review will attempt to comprehensively cover the broad gamut of anesthetic, hemodynamic, antimicrobial, immunosuppressive and hemostatic agents used by the cardiothoracic anesthesiologist in the perioperative management of patients with endstage heart disease.

Progressive Supranuclear Palsy: What Do We Know About it?

Progressive supranuclear palsy (PSP) is a progressive tauopathy characterized by supranuclear ophthalmoplegia, pseudobulbar palsy, dysarthria, axial rigidity, frontal lobe dysfunction, and dementia. The typical pathology includes neuronal loss, gliosis and microtubule-associated protein tau (MAPT)-positive inclusions in neurons and glial cells, primarily in basal ganglia, brainstem and cerebellum. The pathogenesis of PSP is not yet completely understood; however, there are several hypotheses. This article reviews the present knowledge about PSP, and the concepts underlying mitochondrial dysfunction, lipoperoxidation, and gene mutations. The clinical features of PSP are also discussed; these include vertical gaze palsy, pseudobulbar palsy, aphasia, dysarthria, axial rigidity, and neuropsychiatric symptoms, such as amnesia, irritability, loss of interest, and dementia. In terms of diagnosis, there is considerable interest in neuroimaging for detecting PSP; therefore, neuroimaging techniques such as magnetic resonance imaging (MRI) and [18F]- fluorodeoxyglucose positron-emission tomography (FDG-PET) are reviewed. A definitive diagnosis of PSP depends on pathology, and the introduction of new clinical subtypes challenges presents the widely adopted diagnosis criteria. PSP treatments such as serotonin antagonists, α2 receptor antagonists, and coenzyme Q10 are also discussed. There is no curative therapy for PSP; all of the available treatments are palliative.

Does Non-Invasive Brain Stimulation Improve Cognition in Major Depressive Disorder? A Systematic Review

Non-invasive brain stimulation (NIBS) techniques, such as repeated transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), have been increasingly used in different contexts to improve cognitive performance and ameliorate depression symptoms. Considering that major depression is usually accompanied by cognitive deficits, NIBS technique could be also helpful to improve cognition in depressed patients. In this systematic review, we researched for articles published in PubMed/MEDLINE from the first date available to June 2014 that assessed cognitive performance in patients with depression before and after NIBS. Out of 191 references, 25 (16 for rTMS and 9 for tDCS) studies matched our eligibility criteria. Non-invasive brain stimulation interventions, such as rTMS and tDCS seem to be a promising tool for cognitive enhancement in MDD, although several issues and biases (e.g., blinding issues, tests without correction for multiple comparisons, placebo effects and exploratory analyses, practice effects) hinder us to conclude that NIBS technique improve cognition in patients with depression. We discussed possible shortcomings of the included studies, such as the use of different depression treatment protocols, the possibility that some findings were false-positive results of the employed cognitive tasks and whether cognition improvement could have been an epiphenomenon secondary to depression improvement. To conclude, whereas these non-pharmacological, non-invasive techniques are particularly appealing for cognitive improvement in depression, further studies are still warranted to disentangle whether NIBS technique induce positive effects on cognition beyond their antidepressant effects.

Relevance of Excitable Media Theory and Retinal Spreading Depression Experiments in Preclinical Pharmacological Research

In preclinical neuropharmacological research, molecular, cell-based, and systems using animals are well established. On the tissue level the situation is less comfortable, although during the last decades some effort went into establishing such systems, i.e. using slices of the vertebrate brain together with optical and electrophysiological techniques. However, these methods are neither fast, nor can they be automated or upscaled. By contrast, the chicken retina can be used as a suitable model. It is easy accessible and can be kept alive in vitro for hours up to days. Due to its structure, in addition the retina displays remarkable intrinsic optical signals, which can be easily used in experiments. Also to electrophysiological methods the retina is well accessible.

In excitable tissue, to which the brain and the retina belong, propagating excitation waves can be expected, and the spreading depression is such a phenomenon. It has been first observed in the forties of the last century. Later, Martins- Ferreira established it in the chicken retina (retinal spreading depression or RSD). The electrophysiological characteristics of it are identical with those of the cortical SD. The metabolic differences are known and can be taken into account. The experimental advantage of the RSD compared to the cortical SD is the pronounced intrinsic optical signal (IOS) associated with the travelling wave. This is due to the maximum transparency of retinal tissue in the functional state; thus any physiological event will change it markedly and therefore can be easily seen even by naked eye. The theory can explain wave spread in one (action potentials), two (RSDs) and three dimensions (one heart beat).

In this review we present the experimental and the excitable media context for the data interpretation using as example the cholinergic pharmacology in relation to functional syndromes. We also discuss the intrinsic optical signal and how to use it in pre-clinical research.

Common Genetic Conditions of Ischemic Stroke to Keep in Mind

Stroke is a complex disease resulting from the interplay of genetics and environment. In some instances (mainly in young adults) stroke is the direct result of a monogenic disease. Among the monogenic causes of stroke, the diseases which are most frequently encountered in the adult general neurological practice are CADASIL, Fabry and mitochondrial diseases. Brain MRI and clinical features may frequently lead to a correct molecular diagnosis. Here we review the single-gene causes of ischemic stroke, with special regard to the associated features which may help in the diagnostic approach.

NMDA Neurotransmission Dysfunction in Mild Cognitive Impairment and Alzheimers Disease

The prevalence of Alzheimer’s disease (AD) in the elderly is growing rapidly worldwide, and the deteriorating clinical course of AD places a heavy burden on both the patients and their families. Early detection and intervention of mild cognitive impairment in the early phase of AD is vital for the purpose of improving the cognitive performance of patients and preventing the existing deficits from worsening. However, the main compounds currently used to treat early AD, acetylcholinesterase inhibitors (AChEIs), are unsatisfactory in efficacy and safety. Moreover, evidence indicates that AChEIs are ineffective in treating AD at extremely early stages, which implies that mechanisms other than those targeted by AChEIs underlie the pathogenesis of AD. Dysfunctional glutamatergic neurotransmission, particularly that mediated by the N-methyl-D-aspartate (NMDA) receptor, has been reported to play a role in the pathophysiology of AD. The NMDA receptor (NMDAR) regulates synaptic plasticity, memory, and cognition, and the attenuation of NMDAR-mediated neurotransmission can result in impaired neuroplasticity and cognitive deficits in the aging brain. Furthermore, NMDARs also interact with amyloid beta peptide/amyloid precursor protein and tau protein, whose production represents the main manifestations of AD. In this paper, we review the evidence supporting NMDA dysfunction in both animal models of AD and patients afflicted with AD, and we also review the literature that suggests that NMDA-enhancing agents such as glycine and D-cycloserine can improve cognitive functions. The benefits and limitations of NMDAR antagonists that can diminish the excitatory neurotoxicity triggered by glutamate are also addressed in relation to AD. We propose that enhancing glutamatergic neurotransmission by activating the NMDAR may be effective in treating the cognitive decline that occurs in AD. Prospective studies on AD in which NMDA-enhancing agents are used are required to verify this hypothesis and confirm the long-term efficacy and safety of the treatment agents.

Post-stroke Depression Therapy: Where are we now?

Post-stroke depression is an important psychological consequence of ischemic stroke, and affects around one third of stroke patients at any time post-stroke. It has a negative impact on patient morbidity and mortality, and as such development of effective post-stroke recognition and treatment strategies are very important. There are several therapeutic strategies for post-stroke depression, including both pharmacological and non-pharmacological approaches. In this review, we present evidence regarding the underlying biology of post-stroke depression, commonalities between post-stroke depression and Major Depressive Disorder and explore several treatment approaches, including antidepressant therapy, psychotherapy, surgical therapy, electroconvulsive therapy, acupuncture, music therapy and natural products. Further experimental and clinical studies are required, particularly in emerging fields such as the role of nutraceuticals in the treatment of stroke.

Myocardial Ischemia/Reperfusion Injury: Potential of TRPV1 Agonists as Cardioprotective Agents

Myocardial Ischemia/Reperfusion (I/R) induced injury has widespread detrimental effects partially negating the benefits obtained from early revascularization in Acute Myocardial Infarction. Various complex mechanisms contribute to I/R injury and different agents targeting those specific mechanisms are being studied. Despite continued research and widespread interest, none of them have become incorporated into everyday practice. The TRPV1 (transient receptor potential vanilloid 1) channel is a non selective cation channel predominantly expressed in sensory neurons with the nerve fibers innervating the heart and blood vessels. Multiple studies have demonstrated the importance of the activation of TRPV1 and subsequent release of sensory neurotransmitters in cardioprotection. This review focuses on the role of TRPV1 in prevention of cardiac I/R injury, the work that has been done so far and future implications for TRPV1 agonists as cardioprotective agents.

Scopolamine and Depression: A Role for Muscarinic Antagonism?

Depressive disorders have, for a sizeable extent, proven resilient to pharmacotherapy. Established drugs such as selective serotonin reuptake inhibitors (SSRIs) or serotonin-noradrenaline reuptake inhibitors (SNRIs) often provide inadequate symptom relief and sometimes fail altogether. Recently, interest in antidepressant effects of scopolamine, a non-selective muscarinic acetylcholine receptor (mAChR) antagonist, has arisen. Initial evidence suggests that scopolamine provides relatively rapid and long-lasting symptom alleviation for unipolar and bipolar depressed patients. At the same time, side effects of medical dosages appear mild and transient in nature. The aim of the present review is to tentatively discuss the antidepressant potential of scopolamine and to outline putative neurobiological pathways. Clearly, mAChR antagonism provides an intriguing novel therapeutical approach for treating depressive disorders.

Harnessing Anesthesia and Brain Imaging for the Study of Human Consciousness

Philosophers have been trying to solve the mind-body problem for hundreds of years. Consciousness is the core of this problem: How do subjective conscious sensations, perceptions, feelings, and thoughts arise out of objective physical brain activities? How is this subjective conscious world in causal interaction with the objective sensory and motor mechanisms of the brain and the body? Although we witness the seamless interaction of the mental and the physical worlds in our everyday lives, no scientific theory can yet fully describe or explain it. The hard problem of consciousness, the question why and how any brain activity should be accompanied by any subjective experiences at all, remains a mystery and a challenge for modern science. Anesthesia offers a unique and safe way to directly manipulate the state of consciousness and can, thus, be used as a tool in consciousness research. With neuroimaging, such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) performed at different states of consciousness, it is possible to visualize the state-related changes and pinpoint the brain structures or neural mechanisms related to changes in consciousness. With these tools, neurosciences now show promise in disentangling the eternal enigma of human consciousness. In this article, we will review the recent advancements in the field.

General Anesthetics in Brain Injury: Friends or Foes?

General anesthesia-induced pharmacological protection of the central nervous system following injury has been under intense investigations during the past four decades. Indeed, if general anesthetics could provide therapeutic benefit in the event of hypoxia, ischemia or any other kinds of brain lesions, that would be of tremendous clinical importance. The potential for anesthesia-related brain protection, however, has been seriously challenged during the past 10 years. In fact, an increasing number of experimental and, more recently, clinical observations suggest that general anesthetics might exert unwanted, toxic effects on the brain especially when administered to young infants or to the elderly. Of utmost importance, recent data suggest that these same drugs could even have therapeutic effects in some psychiatric disorders. The goal of this review is to highlight these apparent contradictions. We will consider the available experimental evidence arguing for anesthetic-induced neuroprotection and highlight the lack of clinical studies supporting this notion. The biological rational for anesthesia neurotoxicity will then be explored together with existing experimental and clinical evidence in favor of this possibility. Finally, insights into the increasing number of both experimental and clinical data suggesting that general anesthetics, especially ketamine, support the therapeutic value of these drugs in major depressive disorders. When taken together, these seemingly contradictory observations suggest the intriguing possibility that general anesthetics could stand as valuable context-dependent modulators of neural plasticity.

Amantadine, Apomorphine and Zolpidem in the Treatment of Disorders of Consciousness

Survivors of severe brain injuries may end up in a state of ‘wakeful unresponsiveness’ or in a minimally conscious state. Pharmacological treatments of patients with disorders of consciousness aim to improve arousal levels and recovery of consciousness. We here provide a systematic overview of the therapeutic effects of amantadine, apomorphine and zolpidem in patients recovering from coma. Evidence from clinical trials using these commonly prescribed pharmacological agents suggests positive changes of the patients’ neurological status, leading sometimes to dramatic improvements. These findings are discussed in the context of current hypotheses of these agents’ therapeutic mechanisms on cerebral function. In order to improve our understanding of the underlying pathophysiological mechanisms of these drugs, we suggest combining sensitive and specific behavioral tools with neuroimaging and electrophysiological measures in large randomized, double-blind, placebo-controlled experimental designs. We conclude that the pharmacokinetics and pharmacodynamics of amantadine, apomorphine and zolpidem need further exploration to determine which treatment would provide a better neurological outcome regarding the patient’s etiology, diagnosis, time since injury and overall condition.

Disorders of Consciousness and Pharmaceuticals that Act on Oxygen Based Amino Acid and Monoamine Neurotransmitter Pathways of the Brain

Oxygen based neurotransmitters in the synapses of the brain are proposed to play an important role in the generation of consciousness. They include the amino acids glutamate and GABA which use Krebs cycle precursors for their synthesis, and the monoamines dopamine, noradrenalin, adrenalin and serotonin, which are derived from tyrosine and tryptophan.

During ischemia after an acute brain injury, a GABA surge often initiates brain suppression. It has been proposed that with chronic ischemia, a secondary, possibly epigenetic response occurs when neurotransmitters deplete, a glucose and oxygen saving mechanism termed neurodormancy that may invoke alternative long term low energy metabolic pathways in the brain, encountered in Disorders of Consciousness.

Some medications can reverse Disorders of Consciousness in some patients. Virtually all of them act on neurotransmitter systems that use oxygen as a building block or as an energy source within the brain. Pharmaceuticals that act in the oxygen based amino acid systems of the brain include the GABAergic medications zolpidem and baclofen, while those that act in the monoamine axes include the dopaminergic medications L Dopa, amantadine, bromocriptine, apomorphine and methylphenidate, and the noradrenergic and serotonergic medications desipramine, amitriptyline, protriptyline and fluoxetine. Another group are the cholinesterase inhibitors, responsible for increasing acetylcholine, which is synthesized from the Krebs cycle initiator, acetyl CoA.

It appears that pharmaceuticals that are active in the oxygen based neurotransmitter pathways of the brain are successful to arouse to consciousness patients that suffer from its disorders. Research needs to be supported as foundation to understand the biochemical mechanisms that are involved in consciousness disorders and to explore further the pharmacological treatment possibilities for these devastating neurological conditions.

Pharmacological Modulation of the State of Awareness in Patients with Disorders of Consciousness: An Overview

The neurobiological approach to consciousness moves from the assumption that all phenomenal experiences are based on neuronal activity in the brain. Consciousness has two main components: wakefulness and awareness. While it may be relatively easy to determine the neuronal correlates of wakefulness, it is not the same for awareness, of which the neural correlates are poorly understood. Knowledge of the circuitry and the neurochemistry of the sleep/wake condition is necessary but not sufficient to understand the circuitry and neurochemistry of consciousness. Disorders of consciousness (DOCs) include coma, vegetative state and minimally conscious state. The study of DOCs and of the electrophysiological changes underlying general anaesthesia-induced loss of consciousness may help in understanding the neuronal correlates of consciousness. In turn, the understanding of the neural bases of consciousness may help in designing interventions aimed at restoring consciousness in DOC patients. Sporadic cases of recovery from a DOC have been reported after the administration of various pharmacological agents (baclofen, zolpidem, amantadine etc.). This review provides an overview of such drugs, which are from various and diverging classes but can be grouped into two main categories: CNS stimulants and CNS depressants.

The available data seem to suggest an awakening effect obtained with CNS depressants rather than stimulants, the latter being more effective at improving functional cognitive and behavioral recovery in patients who have spontaneously regained an appreciable level of consciousness. There is a need for more rigorous systematic trials and further investigation of the above treatments, with particular attention paid to their mechanisms of action and the neurotransmitters involved.

Conference Proceedings: Second International Conference on Novel Psychoactive Substances (NPS) Swansea, UK; September 12-13th, 2013

Therapeutic Potential of Cannabinoids in Neurodegenerative Disorders: A Selective Review

The endocannabinoid system (ECS) is now recognised as an important modulator of various central nervous system processes. More recently, an increasing body of evidence has accumulated to suggest antioxidant, anti-inflammatory and neuroprotective roles of ECS. In this review we discuss the role and therapeutic potential of ECS in neurodegenerative disorders such as Alzheimer’s disease (AD), Parkinson’s disease, multiple sclerosis, Huntington’s disease, Tourette’s syndrome, brain ischemia and amyotrophic lateral sclerosis (ALS). Elements of the ECS, such as fatty acid amide hydrolase or the cannabinoid receptors are now considered as promising pharmacological targets for some diseases. Although still preliminary, recent reports suggest that modulation of the ECS may constitute a novel approach for the treatment of AD. There are windows of opportunity in conditions caused by acute events such as trauma and ischemia as well in conditions that may involve altered functionality of the target receptors of the ECS, such as in AD. The ECS changes in Parkinson’s disease could be compensatory as well as pathogenic of the illness process and needs further understanding and clinical studies are still in the preliminary stage. There is not enough evidence to support use of cannabinoids in treating Huntington’s disease, tics and obsessive compulsive behaviour in Tourette's syndrome. Evidence on therapeutic use of cannabinoids in multiple sclerosis and ALS is currently limited. A major challenge for future research is the development of novel compounds with more selectivity for various components of the ECS which could target different neurotoxic pathways and be used in combination therapy.

Human Internal Jugular Valve M-mode Ultrasound Characterization

In humans the mechanism governing the internal jugular vein (IJV) valve opening and closure is still unclear. M-mode is used in echo-cardiology for the heart valves assessment. Sometimes it was performed also in deep peripheral veins and in vena cava assessment, but never in the IJV valve. Aim of the present study is to investigate the IJV valves physiology in healthy volunteers, by means of both B and M-mode ultrasound.

Eighty-three (83) healthy volunteers (35 Male, 48 Female, 25.7±6.7 y.o.), for a total of 166 IJVs, were enrolled. The entire cohort underwent IJVs high-resolution B and M-mode evaluation, in standardized postural and respiratory conditions. Presence, motility, and number of cusps, as well as their opening and closure mechanism have been assessed.

Bilateral valve absence occurred in 13/83 (16%), whereas at least a one side absence was recorded in 38/83 (46% of the cohort) (p<0.0356). Valve leaflets were always mobile and respectively bi-cusps in 34%, or mono-cusp in 27%. The latter was significantly more frequent on the left side (35%) than on the right side (19%) (p<0.0013).

In supine, M-mode valve opening was synchronous with the cardiac cycle.

To the contrary, in an upright position, the valve remained always open and saddled to the wall, independently from the cardiac cycle.

In healthy subjects, the IJV valve leaflets are always mobile, but the significant rate of mono and bilateral absence could suggest a progressive phylogenetic importance loss of such apparatus. M-mode ultrasound enhances the characterization of IJV valve, for this reason it should be taken into consideration to routinely add it to the cerebral venous return investigation.

Epigenomic Approach in Understanding Alzheimer’s Disease and Type 2 Diabetes Mellitus

Cognitive decline is a debilitating feature of Alzheimer’s disease (AD). The causes leading to such impairment are still poorly understood and effective treatments for AD are still unavailable. Type 2 diabetes mellitus (T2DM) has been identified as a risk factor for AD due to desensitisation of insulin receptors in the brain. Recent studies have suggested that epigenetic mechanisms may also play a pivotal role in the pathogenesis of both AD and T2DM. This article describes the correlation between AD and T2DM and provides the insights to the epigenetics of AD. Currently, more research is needed to clarify the exact role of epigenetic regulation in the course and development of AD and also in relation to insulin. Research conducted especially in the earlier stages of the disease could provide more insight into its underlying pathophysiology to help in early diagnosis and the development of more effective treatment strategies.

Pathogenesis of Alzheimer Disease: Role of Oxidative Stress, Amyloid-β Peptides, Systemic Ammonia and Erythrocyte Energy Metabolism

Aβ exerts prooxidant or antioxidant effects based on the metal ion concentrations that it sequesters from the cytosol; at low metal ion concentrations, it is an antioxidant, whereas at relatively higher concentration it is a prooxidant. Thus Alzheimer disease (AD) treatment strategies based solely on the amyloid-β clearance should be re-examined in light of the vast accumulating evidence that increased oxidative stress in the human brains is the key causative factor for AD. Accumulating evidence indicates that the reduced brain glucose availability and brain hypoxia, due to the relatively lower concentration of ATP and 2,3-diphosphoglycerate, may be associated with increased concentration of endogenous ammonia, a potential neurotoxin in the AD brains. In this review, we summarize the progress in this area, and present some of our ongoing research activities with regard to brain Amyloid-β, systemic ammonia, erythrocyte energy metabolism and the role of 2,3-diphosphoglycerate in AD pathogenesis.

Choline Alphoscerate (Alpha-Glyceryl-Phosphoryl-Choline) An Old Choline- containing Phospholipid with a Still Interesting Profile As Cognition Enhancing Agent

Cholinergic precursors have represented the first approach to counter cognitive impairment occurring in adultonset dementia disorders. These compounds were early leaved because their clinical efficacy was not clearly demonstrated. This is probably not true for some choline-containing phospholipids including choline alphoscerate. Choline alphoscerate increases the release of acetylcholine in rat hippocampus, facilitates learning and memory in experimental animals, improves brain transduction mechanisms and decreases age-dependent structural changes occurring in rat brain areas involved in learning and memory. The compound exerts neuroprotective effects in models of altered cholinergic neurotransmission and of brain vascular injury. In clinical studies choline alphoscerate improved memory and attention impairment, as well as affective and somatic symptoms in dementia disorders. An ongoing trial indicates that association between the acetylcholinesterase inhibitor donepezil and choline alphoscerate is accompanied by an improvement in several cognitive tests superior to that induced by donepezil alone. It is suggested that this association may represent a therapeutic option to prolong beneficial effects of cholinergic therapies in Alzheimer’s disease patients with concomitant ischemic cerebrovascular disorders. In summary, choline alphoscerate has significant effects on cognitive function with a good safety profile and tolerability. Although limited both in terms of size of the samples investigated and of the length of treatment, preclinical and clinical results presented suggest that cognitive enhancing capabilities of choline alphoscerate merit of being further investigated in appropriate trials.

Antioxidant Activity of Galantamine and Some of its Derivatives

Oxidative stress is implicated in the pathogenesis of different human diseases: Alzheimer, Parkinson, Huntington, amyotrophic lateral sclerosis (Lou Gehrig's disease), Down’s syndrome, atherosclerosis, vascular disease, cancer, diabetes mellitus type 1 and type 2, age – related macular degeneration, psoriatic arthritis. The aim of current study is to summarize the scientific evidences for the antioxidant and neuroprotective activity of Galantamine and some of its derivatives. Galantamine is a scavenger of reactive oxygen species and causes neuroprotective effect by lowering the oxidative neuronal damage, through the following pathways: 1) prevention of the activation of P₂X₇ receptors; 2) protection of mitochondrial membrane potential; 3) pre – vention of the membrane fluidity disturbances. Another mechanism is the decreasing of the overproduction of reactive oxygen species, a result from the increasing of acetylcholine level due to: 1) acethylcholinesterase inhibition; 2) allosteric potentiation of α7 – subtype of nicotinic acetylcholine receptors. A close relationship between acethylcholinesterase inhibition and reduced oxidative injury is observed. Through allosteric potentiation of the α7 – subtype of nicotinic acetylcholine receptors, the drug leads to induction of phosphorylation of serine – threonine protein kinase, stimulates phosphoinositide 3 – kinase and elevates the expression of protective protein Bcl – 2. By activation of these important neuroprotective cascades, Galantamine exerts neuroprotection against a variety of cytotoxic agents (β – amyloid peptide, glutamate, hydrogen peroxide, oxygen and glucose deprivation). The new trend in therapy of Alzheimer's disease will be the investigation and application of compounds such as Galantamine derivatives, which possess acethylcholinesterase and γ – secretase inhibitory activity and antioxidant properties.

BACE1 Levels Correlate with Phospho-Tau Levels in Human Cerebrospinal Fluid

Previous studies have investigated the activity and protein levels of BACE1, the β-secretase, in the brain and cerebrospinal fluid (CSF) of Alzheimer’s disease (AD) patients, however, results remain contradictory. We present here a highly specific and sensitive BACE1 ELISA, which allows measuring accurately BACE1 levels in human samples. We find that BACE1 levels in CSF of AD patients and other neurological disorder (OND) patients are slightly increased when compared to those of a non-neurological disorder control group (NND). BACE1 levels in CSF were well correlated with total-tau and hyperphosphorylated tau levels in the CSF, suggesting that the recorded alterations in BACE1 levels correlate with cell death and neurodegeneration.

From Preclinical to Clinical Trials: An Update on Potential Therapies for Huntington’s Disease

Huntington’s disease (HD) is a neurodegenerative disorder caused by a CAG expansion in the HD gene that codifies the protein huntingtin and characterized by neurodegeneration of certain areas of the brain, particularly the striatum and the cortex. The first symptoms usually appear in mid-life and include cognitive deficits and motor disturbances that progress over time. The disease is invariable fatal and there is currently no cure for individuals affected with this disorder. In a search to find a cure for this devastating neurodegenerative disorder, numerous pharmacological compounds have now been tested through preclinical trials that have heavily relied on the various transgenic mouse models that are currently available to study HD. Unfortunately however, to date the benefits observed in the clinical setting have been somewhat limited. We have recently published a review article comparing the results of these preclinical studies with the outcomes of the corresponding clinical trials involving HD afflicted individuals (Brocardo and Gil- Mohapel, 2012, Current Psychopharmacology 1:137-154). In the present article we present an update to our previous review, where the new preclinical and clinical studies that have been performed over the past year have been also discussed with the goal of further elucidating the efficacy of the pharmacological treatments that have been attempted in both transgenic HD mouse models and human HD patients. By providing and maintaining an up-to-date overview of the most current literature, we hope that patterns will emerge that will guide the design of more effective preclinical and clinical studies, such as the use of combination therapies that utilize different cocktails of pharmacological compounds to simultaneously target different intracellular pathways that are affected in HD.

Electroencephalography and Dementia: A Literature Review and Future Perspectives

While many studies have investigated electroencephalographic (EEG) features of dementia, few have analysed the relationship between EEG and cerebrospinal fluid biomarkers in cognitive impairment. Seizures are frequently observed at the end stage of Alzheimer disease, and experimental animal studies support the view that epileptiform activity may contribute to the cognitive decline. In this paper, after reviewing literature findings concerning the role of EEG in dementia, we show the preliminary results of our study aimed to correlate the presence of epileptiform EEG patterns with cerebrospinal fluid biomarkers in order to better define the prognosis of dementia. Our study shows a clear relationship between phospho-tau protein levels and epileptiform EEG pattern. This finding seems to suggest in humans the observation made in animal models that not only β-amyloid protein, but also tau and phospho-tau proteins, are involved in the aberrant regulation of neural transmission possibly contributing to EEG deterioration, cognitive decline and worse prognosis. On the basis of the relationship between phospho-tau protein, cognitive decline and epileptogenicity we suspect that high liquoral phospho-tau levels and epileptiform EEG pattern may provide an early identification of patients with dementia and/or represent an aggressive phenotype of dementia. We propose that qualitative EEG analysis integrated with cerebrospinal biomarkers may be extensively used to better define dementia.

Efficacy and Toxicity of Clioquinol Treatment and A-beta42 Inoculation in the APP/PSI Mouse Model of Alzheimer's Disease

Alzheimer’s disease (AD), the most common human neurodegenerative disease, is characterized pathologically by numerous deposits of amyloid plaques in the brain. Systemic administration of clioquinol (CQ) and inoculation with amyloid-beta42 (Aβ42) vaccines have been demonstrated to significantly inhibit deposits of amyloid in AD brains. However, each of these treatments has also been reported to be neurotoxic. The generation of transgenic mice models of AD has made it possible to study aspects of this disease employing experimental animals. In the present study, we investigated the efficacy and toxicity of CQ and Aβ42 vaccine in a transgenic AD (APP/PS1) mouse model. Our results confirmed that both CQ and Aβ42 vaccine were effective in significantly reducing the deposits of amyloid in the brains of transgenic AD mice. We also report here that systemic CQ induces myelinopathies in the dorsal lateral geniculate nucleus (DLG), which was almost devoid of amyloid plaques and is the primary site of retinal efferent projections via the optic nerve. This is the first report that systemic administration of CQ causes myelinopathies in the central nervous system (CNS) of a transgenic AD mouse model as well as wild-type mice. Inoculation with an Aβ42 vaccine was also found, for the first time, to result in a significant increase in plaque-independent astrocytic hyperplasia in the dorsal part of the lateral septal nucleus (LSD) which was also devoid of plaques, reflecting potential brain inflammatory processes.

The Safety, Tolerability, Pharmacokinetics and Cognitive Effects of GSK239512, a Selective Histamine H₃ Receptor Antagonist in Patients with Mild to Moderate Alzheimer’s Disease: A Preliminary Investigation

Background: The histamine H₃ receptor plays a critical role in the negative neuromodulation of neurotransmitters involved in cognitive function. H₃ receptor antagonists/inverse agonists have been shown to exert pro-cognitive effects in pre-clinical models. GSK239512 is a potent and selective H₃ receptor antagonist developed for the treatment of cognitive dysfunction in neurodegenerative disorders. In this study we examined the safety, tolerability, pharmacokinetics and pro-cognitive effects of GSK239512 (oral) in patients with mild to moderate Alzheimer’s disease using ascending dose titration regimens.

Methods: The study was conducted in two parts. Part A was a single-blind, placebo run-in, flexible dose titration over 9 days in two cohorts, each consisting of two patients. Part B was a double-blind, randomised, placebo controlled, parallel group, which investigated 3 flexible dose titration regimens over 4 weeks in 3 cohorts, each consisting of eight patients.

Results: Overall, the 5/10/20/40μg and 10/20/40/80μg regimens were well-tolerated. The regimen of 20/40/80/150μg showed the poorest tolerability likely due to the higher starting dose. There were no clinically significant abnormalities in haematology, clinical chemistry, urinalysis parameters and cardiovascular parameters. GSK239512 had positive effects on tasks of attention and memory with effect sizes between 0.56 and 1.37.

Conclusions: GSK239512 displayed asatisfactory level of tolerability in patients with Alzheimer’s disease with evidence for positive effects on attention and memory. The findings suggest that a titration regimen with a starting dose of 5-10μg and a maximum dose of 80μg is likely to be a well-tolerated and potentially efficacious regimen for future clinical trials in patients with Alzheimer’s disease. These findings await replication in a larger study.

Beneficial Effects of Herbs, Spices and Medicinal Plants on the Metabolic Syndrome, Brain and Cognitive Function

Herbs and spices have been used since ancient times to not only improve the flavor of edible food but also to prevent and treat chronic health maladies. While the scientific evidence for the use of such common herbs and medicinal plants then had been scarce or lacking, the beneficial effects observed from such use were generally encouraging. It is, therefore, not surprising that the tradition of using such herbs, perhaps even after the advent of modern medicine, has continued. More recently, due to an increased interest in understanding the nutritional effects of herbs/spices more comprehensively, several studies have examined the cellular and molecular modes of action of the active chemical components in herbs and their biological properties. Beneficial actions of herbs/spices include anti-inflammatory, antioxidant, anti-hypertensive, gluco-regulatory, and anti-thrombotic effects. One major component of herbs and spices is the polyphenols. Some of the aforementioned properties are attributed to the polyphenols and they are associated with attenuating the metabolic syndrome. Detrimental changes associated with the metabolic syndrome over time affect brain and cognitive function. Metabolic syndrome and type-2 diabetes are also risk factors for Alzheimer’s disease and stroke. In addition, the neuroprotective effects of herbs and spices have been demonstrated and, whether directly or indirectly, such beneficial effects may also contribute to an improvement in cognitive function. This review evaluates the current evidence available for herbs/spices in potentially improving the metabolic syndrome, as well as their neuroprotective effects on the brain, and cognitive function in animal and human studies.

Encephalopathy: A Vicious Cascade Following Forebrain Ischemia and Hypoxia

Post ischemic/hypoxic encephalopathy is a progressive and widespread damage syndrome in human brain, which includes production of new ischemic foci as well as neurodegeneration associated with accumulation of amyloid protein (Aβ), which emerges within days after the primary ischemic or hypoxic ictus. Patients may suddenly suffer severe dementia and Parkinson’s syndrome after a symptom-free period averaging 2 weeks following resuscitation. Death of neurons in the cortex, limbic system, globus pallidus (GP) and substantia nigra (SN) and damage to white matter are responsible. From experimental studies in animals evidence is obtained to reveal the mechanisms. Injured endothelia and activated platelets lead to secondary injury via thrombosis and vasoconstriction resulting in infarction and new foci of necrosis. Blood-brain barrier (BBB) breakdown allows penetration of blood-borne toxic substances into brain resulting in neuronal degeneration and enhanced inflammatory destruction. These secondary injuries happen within two weeks after moderate global ischemia. As these pathological changes cycle between the vascular and neuronal compartments, the damage expands and worsens. Aβ, β amyloid precursor protein (βAPP) and the inflammation mediator cyclooxygenase-2 (COX2) as well as γ-aminobutyric acid (GABA) system degeneration participate in producing secondary injury. Thus, implementing multi-targeted prophylaxis before or at the brain-at-risk stage is desirable. A combination of protecting endothelia, inhibiting platelet activity and improving cerebral circulation is a fundamental strategy to block this vicious cascade, thereby ameliorating or preventing the encephalopathy.

Melanocortins As Innovative Drugs for Ischemic Diseases and Neurodegenerative Disorders: Established Data and Perspectives

Ischemic insults and neurodegenerative diseases are by far the leading cause of mortality and disability. Whole-body hypoperfusion, as it occurs in polytraumatic and hemorrhagic shock, is alike an increasingly frequent condition, especially due to traffic accidents, wars and acts of terrorism. It is now clearly established that inflammatory processes play a fundamental role in the pathophysiology of both hypoperfusion/ischemia damage (be it generalized to the whole body, as in the case of shock, or limited to individual organs) and neurodegenerative diseases (Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, amyotrophic lateral sclerosis). On the other hand, concurrent animal and human data show that melanocortin peptides with agonist activity at melanocortin MC3/MC4 receptors are highly effective in different shock conditions as well as in conditions of ischemia/ischemia-reperfusion of individual organs (heart, brain, intestine, kidney, etc.), and accumulating evidence indicates that such effects of melanocortins are mostly due to quite peculiar antiinflammatory mechanisms. Melanocortins have also long been known (i) to exert important neurotrophic effects, not only during fetal development but also in adulthood, in different animal models of brain lesions; (ii) to reduce the morphological correlates of brain aging; (iii) to retard the behavioral deficits that develop during the aging process. Moreover, recent data from different laboratories show that after brain ischemic episodes melanocortins activate the transcription of neurotrophins and their receptors in the cerebral cortex and in the hippocampus, and increase the proliferation of progenitor neuron cells. The above arguments support the view that pharmacokinetically suitable agonists at MC3/MC4 melanocortin receptors may represent a completely innovative class of drugs for an effective treatment of both ischemic and neurodegenerative diseases.

Effects of Snake Venom Polypeptides on Central Nervous System

The nervous system is a primary target for animal venoms as the impairment of its function results in the fast and efficient immobilization or death of a prey. There are numerous evidences about effects of crude snake venoms or isolated toxins on peripheral nervous system. However, the data on their interactions with the central nervous system (CNS) are not abundant, as the blood-brain barrier (BBB) impedes penetration of these compounds into brain. This updated review presents the data about interaction of snake venom polypeptides with CNS. Such data will be described according to three main modes of interactions:

- Direct in vivo interaction of CNS with venom polypeptides either capable to penetrate BBB or injected into the brain.

- In vitro interactions of cell or sub-cellular fractions of CNS with crude venoms or purified toxins.

- Indirect effects of snake venoms or their components on functioning of CNS under different conditions.

Although the venom components penetrating BBB are not numerous, they seem to be the most suitable candidates for the leads in drug design. The compounds with other modes of action are more abundant and better studied, but the lack of the data about their ability to penetrate BBB may substantially aggravate the potentials for their medical perspectives. Nevertheless, many such compounds are used for research of CNS in vitro. These investigations may give invaluable information for understanding the molecular basis of CNS diseases and thus lay the basis for targeted drug design. This aspect also will be outlined in the review.

The Animal Models of Dementia and Alzheimer’s Disease for Pre-Clinical Testing and Clinical Translation

Dementia is a clinical syndrome with abnormal degree of memory loss and impaired ability to recall events from the past often characterized by Alzheimer’s disease. The various strategies to treat dementia need validation of novel compounds in suitable animal models for testing their safety and efficacy. These may include novel anti-amnesic drugs derived from synthetic chemistry or those derived from traditional herbal sources. Multiple approaches have been adopted to create reliable animal models ranging from rodents to non-human primates, where the animals are exposed to a predetermined injury or causing genetic ablation across specific regions of brain suspected to affect learning functions. In this review various animal models for Alzheimer’s disease and treatment strategies in development of anti dementia drugs are discussed and an attempt has been made to provide a comprehensive report of the latest developments in the field.

N-Methyl D-Aspartate (NMDA) Receptor Antagonists and Memantine Treatment for Alzheimer’s Disease, Vascular Dementia and Parkinson’s Disease

Memantine, a partial antagonist of N-methyl-D-aspartate receptor (NMDAR), approved for moderate to severe Alzheimer’s disease (AD) treatment within the US and Europe under brand name Namenda (Forest), Axura and Akatinol (Merz), and Ebixa and Abixa (Lundbeck), may have potential in alleviating additional neurological conditions, such as vascular dementia (VD) and Parkinson’s disease (PD). In various animal models, memantine has been reported to be a neuroprotective agent that positively impacts both neurodegenerative and vascular processes. While excessive levels of glutamate result in neurotoxicity, in part through the over-activation of NMDARs, memantine—as a partial NMDAR antagonist, blocks the NMDA glutamate receptors to normalize the glutamatergic system and ameliorate cognitive and memory deficits. The key to memantine’s therapeutic action lies in its uncompetitive binding to the NMDAR through which low affinity and rapid off-rate kinetics of memantine at the level of the NMDAR-channel preserves the physiological function of the receptor, underpinning memantine’s tolerability and low adverse event profile. As the biochemical pathways evoked by NMDAR antagonism also play a role in PD and since no other drug is sufficiently effective to substitute for the first-line treatment of L-dopa despite its side effects, memantine may be useful in PD treatment with possibly fewer side effects. In spite of the relative modest nature of its adverse effects, memantine has been shown to provide only a moderate decrease in clinical deterioration in AD and VD, and hence efforts are being undertaken in the design of new and more potent memantine-based drugs to hopefully provide greater efficacy.

Therapeutic Strategies for Huntingtons Disease: From the Bench to the Clinic

Huntingtons disease (HD) is a neurodegenerative disorder caused by a CAG expansion in the HD gene that codifies the protein huntingtin. The disease is characterized by neurodegeneration of certain areas of the brain, particularly the striatum and the cortex. The first symptoms usually appear in mid-life and include cognitive deficits and motor disturbances that progress over time. The disease is invariable fatal and there is currently no cure for individuals affected with this disorder. HD transgenic mouse models have served as useful tools not only to elucidate the mechanisms underlying neurodegeneration in the HD brain, but also to test a number of therapeutic strategies for this disease. As a consequence of the promising results obtained in some of these preclinical studies, various pharmaceutical compounds have now been used in clinical trials. However, in most cases, the benefits observed in the clinical setting have been somewhat limited and, as such, the search for effective treatments still continues. In this review we present an overview of the various therapeutic strategies for HD that have received attention during the past decades, including the use of essential fatty acids, creatine, co-enzyme Q10, remacemide, riluzole, memantine, cystamine, minocycline, and tetrabenazine. We compare their efficacy in mitigating the neuropathology and symptoms of HD transgenic mouse models with the results that have been obtained with these compounds in clinical trials. Finally, we outline some recommendations that should be considered when designing future preclinical and clinical trials for the screening of potential therapeutic strategies for HD.

“Vascular Incontinence” and Normal-Pressure Hydrocephalus: Two Commonsources of Elderly Incontinence with Brain Etiologies

This paper reviewed two common sources of elderly incontinence with brain etiologies, “vascular incontinence” (a disorder of bladder control resulting from cerebral white matter disease) and normal-pressure hydrocephalus (NPH), from a neurological point of view. Both diseases manifest with gait disturbance, dementia, and urinary incontinence. Urinary frequency/ urgency (overactive bladder, OAB) often precedes urinary incontinence in both diseases, and in some patients may be the initial manifestation. While NPH is less common than vascular incontinence, at approximately one-tenth the prevalence, it is important because the symptoms can be reversed by shunt surgery or endoscopic third ventriculostomy. For vascular incontinence, early identification of risk factors and initiation of secondary prevention are necessary. Detrusor overactivity due to frontal hypofunction may underlie the bladder disorder in both diseases. Treatment options for urinary incontinence include anticholinergics, which do not easily penetrate the blood-brain barrier, or newer drugs that act on the adrenergic beta-3 receptor and other receptors.

The Role of Venous Abnormalities in Neurological Disease

The role of the venous circulation has long been underestimated in clinical practice and in research into neurological diseases. In this review, we present an overview of the existing evidence that venous abnormalities can play a key role in the development and manifestation of neurological and neurodegenerative diseases. We review the history behind the role of venous diseases in multiple sclerosis and their connections with the disease landmarks, the links of chronic venous hypertension to cerebral hydrodynamics and the role of iron in MS. In addition, we highlight the role of venous abnormalities in other diseases including jugular venous reflux, developmental anomalies, hydrocephalus and cerebrospinal fluid flow. Finally, and based on the information presented throughout the whole review, we conclude with the link between chronic cerebrospinal venous insufficiency and MS and the role and power of magnetic resonance imaging in diagnosing venous anomalies.

Quantitative Flow Measurements in the Internal Jugular Veins of Multiple Sclerosis Patients Using Magnetic Resonance Imaging

Purpose: To study the blood flow through the internal jugular veins (IJVs) of the MS population.

Materials and Methods: Two hundred MS patients and 14 normal volunteers were evaluated with magnetic resonance imaging (MRI) at 3T. Contrast-enhanced time-resolved 3D MR angiography and 2D time-of-flight imaging were performed to assess abnormalities in the extracranial vascular anatomy. Based on this assessment, the MS population was divided into subgroups of non-stenotic (NST), cervical 1 stenotic only (C1ST) and cervical 6 stenotic (C6ST) subjects. In this study, 2D phase contrast MR imaging was used to quantify blood flow through major veins and arteries in the neck and flow differences among the groups were analyzed.

Results: Of the 200 MS patients, 87 (43.5%) belonged to the NST group, 50 (25%) belonged to the C1ST group and 63 (31.5%) belonged to the C6ST group. The total IJV flow normalized to the total arterial flow of the NST group was 75.12 ± 12.22 %. This was significantly higher than that of the C1ST group, 63.93 ± 16.08 % (p<0.0001), which in turn was significantly higher than that of the C6ST group, 52.13 ± 20.71 % (p = 0.001). Seventy-nine percent of the stenotic groups had a normalized subdominant IJV flow of less than 20%, a combined IJV flow of less than 50% and/or a sub-dominant IJV flow vs. dominant IJV flow ratio of less than 1/3. Only 2% of the NST group had a combined IJV flow of less than 50%, compared to 35% of the stenotic groups.

Conclusion: Blood flow through the IJVs was reduced in the MS population with stenoses compared to those without.

Neurosteroid PREGS Protects Neurite Growth and Survival of Newborn Neurons in the Hippocampal Dentate Gyrus of APPswe/PS1dE9 Mice

Neurosteroids pregnenolone-sulfate (PREGS) and dehydroepiandrosterone (DHEA) have been shown to enhance neurogenesis in the hippocampal dentate gyrus (DG) of adult rodents. In Alzheimer’s disease (AD) brain, the levels of these neurosteroids are known to be altered compared to age-matched non-demented controls. The aim of this study was to examine the effects of PREGS and DHEA on the hippocampal neurogenesis in 8-month-old male APPswe/PS1dE9 transgenic (APP/PS1) mice that show amyloid plaques and impaired spatial cognitive performance. In the DG of APP/PS1 mice the proliferation of progenitor cells was increased, while the neurite growth and survival of newborn neuronal cells were markedly impaired. Treatment with PREGS or DHEA rescued perfectly the hypoplastic neurite of newborn neurons in APP/PS1 mice, while neither of them affected the over-proliferation of progenitor cells. Notably, the administration of PREGS, but not DHEA, to APP/PS1 mice could protect the survival and maturation of newborn neuronal cells, which was accompanied by the improvement of spatial cognitive performance. The results indicate that treatment of AD like brains of APP/PS1 mice with PREGS might protect the hippocampal neurogenesis, leading to the improved spatial cognitive performance

Sibutramine Effects on Central Mechanisms Regulating Energy Homeostasis

During the last 50 years the global pandemic of obesity and associated life-threatening co-morbidities strongly promoted the development of anti-obesity pharmacotherapy. Sibutramine is an anti-obesity drug that in conjunction with lifestyle modifications reduces food intake and body weight. This may result from several effects: inhibition of presynaptic reuptake of monoaminergic neurotransmitters in the central nervous system, thereby suppressing appetite, induction of an increase in anorexigenic and a decrease in orexigenic neuropeptide secretion, induction of an increase in energy expenditure, and induction of peripheral sympathomimetic effects. The effects of sibutramine on anabolic and catabolic signals that regulate energy homeostasis in the hypothalamus are not completely understood. So, the aim of this review is to summarize the central mechanisms of action of sibutramine, responsible for its weight and food intake reducing potential. Despite being a useful drug in obesity treatment, awareness about the loss of long-term effectiveness and detrimental side effects of sibutramine has recently emerged. As a consequence, new drugs that produce safer and more persistent weight loss are currently undergoing clinical trials.

Ethnobotanical Treatment Strategies Against Alzheimers Disease

Ethnobotany encompasses the cultural uses of plants by humans, including their uses as medicines (ethnopharmacology). The reputed medicinal properties of plants have been documented for centuries in different cultures, and there are many plant species that have been traditionally used for memory disorders, which are now being explored to determine any scientific basis for their reputed uses. Plants have been a valuable source of drugs, and phytochemicals have also provided templates to develop synthetic drugs (e.g. rivastigmine, based on the chemical structure of physostigmine from Physostigma venenosum). Although drug development from botanical origin is one aim, the use of plants as herbal medicines is still popular. Scientific evidence for efficacy and safety has been explored for many species, although more research is needed, particularly to identify active phytochemicals to produce standardised herbal products. For Alzheimers disease (AD) there are relatively few drugs available to treat symptoms, and there is a lack of successful therapies that modulate disease progression. Since two of the currently licensed drugs for AD are based on natural products (galantamine and rivastigmine), it is not surprising that many plants are now being investigated as a potential source of new therapies for AD. This review discusses those plants that have ethnobotanical uses suggestive of alleviation of AD pathology and associated symptoms, for cognitive and for behavioural and psychological symptoms of dementia (BPSD). An emphasis is placed on those plants that have shown some promising effects in clinical studies with dementia patients (e.g. Crocus sativus, Ginkgo biloba, Salvia species), but other plants and their phytochemicals showing relevant mechanistic effects for AD (e.g. Bacopa monnieri, Centella asiatica, Ptychopetalum olacoides) are also discussed.

Chronic Stress and Alzheimers Disease-Like Pathogenesis in a Rat Model: Prevention by Nicotine

Environmental factors including chronic stress may play a critical role in the manifestation of Alzheimers disease (AD).This review summarizes our studies of the aggravation of the impaired cognitive ability and its cellular and molecular correlates by chronic psychosocial stress and prevention by nicotine in an Aβ rat model of AD. We utilized three approaches: learning and memory tests in the radial arm water maze, electrophysiological recordings of the cellular correlates of memory, long-term potentiation (LTP) and long-term depression (LTD), in anesthetized rats, and immunoblot analysis of synaptic plasticity- and cognition-related signaling molecules. The Aβ rat model, representing the sporadic form of established AD, was induced by continuous i.c.v. infusion of a pathogenic dose of Aβ peptides via a 14- day osmotic pump. In this AD model, chronic stress intensified cognitive deficits, accentuated the disruption of signaling molecules levels and produced greater depression of LTP than what was seen with Aβ infusion alone. Chronic treatment with nicotine was highly efficient in preventing the effects of Aβ infusion and the exacerbating impact of chronic stress. Possible mechanisms for the effect of chronic stress are discussed.

Recreational Drug Misuse and Stroke

Stroke is the third commonest cause of death and single largest cause of adult disability worldwide. Whilst the majority of strokes in older individuals are due to large or small vessel arterial disease or cardiac disease in association with classical vascular risk factors, strokes occurring in younger individuals may have atypical etiologies. Recreational substance misuse is on the increase worldwide, particularly in young adults in developed countries with commonly used substances including cocaine, amphetamines, heroin and other opiates, marijuana and gammahydroxybutyrate (GHB). Adverse vascular sequelae of inappropriate use of these substances is well recognized but the link between acute stroke and substance misuse is often underestimated. Both ischemic and hemorrhagic strokes may be caused by recreational substance misuse and this paper reviews the available evidence and discusses the potential pathophysiological links.

State Dissociation, Human Behavior, and Consciousness

Sleep is clearly not only a whole-brain or global phenomenon, but can also be a local phenomenon. This accounts for the fact that the primary states of being (wakefulness, NREM sleep, and REM sleep) are not necessarily mutually exclusive, and components of these states may appear in various combinations, with fascinating clinical consequences. Examples include: sleep inertia, narcolepsy, sleep paralysis, lucid dreaming, REM sleep behavior disorder, sleepwalking, sleep terrors, out-of-body experiences, and reports of alien abduction. The incomplete declaration of state likewise has implications for consciousness - which also has fluid boundaries. Fluctuations in the degree of consciousness are likely explained by abnormalities of a “spatial and temporal binding rhythm” which normally results in a unified conscious experience. Dysfunctional binding may play a role in anesthetic states, autism, schizophrenia, and neurodegenerative disorders. Further study of the broad spectrum of dissociated states of sleep and wakefulness that are closely linked with states of consciousness and unconsciousness by basic neuroscientists, clinicians, and members of the legal profession will provide scientific, clinical and therapeutic insights, with forensic implications.

Reciprocal Interactions Between Wakefulness and Sleep Influence Global and Regional Brain Activity

Reciprocal interactions between wakefulness and sleep substantially influence human brain function in both states of vigilance. On the one hand, there is evidence that regionally-specialized brain activity during wakefulness is modulated by the interaction between a local use-dependent buildup of homeostatic sleep pressure and circadian signals. On the other hand, brain activity during sleep, although mainly constrained by genuine sleep oscillations, shows wakedependent regionally-specific modulations, which are involved in the dissipation of local homeostatic sleep pressure and memory consolidation.

Chronic Cerebrospinal Venous Insufficiency (CCSVI) and Multiple Sclerosis (MS): A Critical Review

Multiple sclerosis (MS) is a chronic disease of the central nervous system with not yet completely understood pathogenesis. The so called “chronic cerebrospinal venous insufficiency (CCSVI) theory” has recently emerged, supporting the concept of a cerebrospinal venous drainage impairment as the cause of MS. Since the first publication on this topic with a claimed 100% specificity and sensitivity of the condition for MS diagnosis, CCSVI theory has generated a scientific and mass media debate with a great hope for the miracle of a new possible endovascular treatment of MS (“liberation procedure”). We critically summarize the available evidence on CCSVI discussing inconsistent and incomplete replication of the original results by different groups, methodological limitations and potential therapeutic implications. We conclude that the available data are insufficient to establish conclusively a clear relationship between MS and CCSVI and do not support the role of CCSVI as the primary cause of MS. Until credible scientific evidence replicates the original results, any proposed invasive treatments of CCSVI should be discouraged.

Anti-NMDA Receptor Encephalitis in Psychiatry

Anti-NMDA receptor encephalitis is an autoimmune disorder in which antibodies attack NMDA (N-methyl-Daspartate)-type glutamate receptors at central neuronal synapses. Symptoms include a highly characteristic set of neurologic deficits, but also prominent psychiatric manifestations that often bring mental health professionals into the course of care. Distinct phases of illness have become increasingly appreciated, and include a range of psychotic symptoms early in the course of the disease followed by more severe fluctuations in consciousness with neurologic involvement, and ultimately protracted cognitive and behavioral deficits. Young women are most commonly impacted and an ovarian teratoma is sometimes associated with the syndrome. Patients respond well to immunotherapy, but psychiatric symptoms can be challenging to manage. We provide an up to date review of this disorder and highlight the role of psychiatry in diagnosis, symptomatology, and treatment.

Mitochondrial Toxicity in HAART: An Overview of In Vitro Evidence

The combined antiretroviral therapeutic approach currently employed for the treatment of HIV infection, known as Highly Active Antiretroviral Therapy (HAART), has dramatically reduced AIDS-related morbidity and mortality. However, the adverse reactions associated with the long term use of this therapy have now become a major issue and researchers have focused on understanding the cellular mechanisms underlying these drug-induced detrimental effects which englobe a large list of different events including rash and hypersensibility reactions, hepatotoxicity, metabolic disturbances including lipodystrophy, and other metabolic syndrome-like disturbances such as hyperlactatemia, hyperlipedimia, insulin resistance and pancreatitis. Other events include CNS toxic effects, peripheral neuropathies as well as nephrotoxicity and increased risk of cardiovascular diseases. Many of these reactions have been shown to develop as a result of mitochondrial dysfunction. The mitochondrial effect of N(t)RTI (Nucleos( t)ide Reverse Transcriptase Inhibitors) class of drugs, which has been widely studied, is believed to originate from the inhibitory action of these drugs on DNA polymerase gamma, the enzyme responsible for replication of mitochondrial DNA. However, additional mitochondrial targets have also been described and need to be considered. As to NNRTI (Non-Nucleoside-Transcriptase Inhibitor) or PI (Protease Inhibitors), evidence of the implication of mitochondria has also been reported, however the details of the mechanisms underlying these actions are still not fully known. This review covers the current knowledge of mitochondrial toxicities, particularly the available in vitro evidence, regarding the most commonly used groups of HIV drugs. Novel findings of mtDNA-independent mitochondrial dysfunction have received special attention.

Stem Cell Therapy for Alzheimers Disease

Alzheimers disease (AD) is a progressive neurodegenerative disorder which impairs the memory and intellectual abilities of the affected individuals. Loss of episodic as well as semantic memory is an early and principal feature. The basal forebrain cholinergic system is the population of neurons most affected by the neurodegenerative process. Extracellular as well as intracellular deposition of β- amyloid or Abeta (Aβ) protein, intracellular formation of neurofibrillary tangles and neuronal loss are the neuropathological hallmarks of AD. In the last few years, hopes were raised that cell replacement therapy would provide cure by compensating the lost neuronal systems. Stem cells obtained from embryonic as well as adult tissue and grafted into the intact brain of mice or rats were mostly followed by their incorporation into the host parenchyma and differentiation into functional neural lineages. In the lesioned brain, stem cells exhibited targeted migration towards the damaged regions of the brain, where they engrafted, proliferated and matured into functional neurones. Neural precursor cells can be intravenously administered and yet migrate into brain damaged areas and induce functional recovery. Observations in animal models of AD have provided evidence that transplanted stem cells or neural precursor cells (NPCs) survive, migrate, and differentiate into cholinergic neurons, astrocytes, and oligodendrocytes with amelioration of the learning/memory deficits. Besides replacement of lost or damaged cells, stem cells stimulate endogenous neural precursors, enhance structural neuroplasticity, and down regulate proinflammatory cytokines and neuronal apoptotic death. Stem cells could also be genetically modified to express growth factors into the brain. In the last years, evidence indicated that the adult brain of mammals preserves the capacity to generate new neurons from neural stem/progenitor cells. Inefficient adult neurogenesis may contribute to the pathogenesis of AD and other neurodegenerative disorders. An attempt at mobilizing this endogenous pool of resident stem-like cells provides another attractive approach for the treatment of AD. Studies in patients with AD indicated decreased hippocampal volume derived by neurodegeneration. Intriguingly, many drugs including antidepressants, lithium, acetyl cholinesterase inhibitors, and ginkgo biloba, were able to enhance the impaired neurogenesis in this disease process. This paved the way towards exploring the possible pharmacological manipulation of neurogenesis which would offer an alternative approach for the treatment of AD.

Therapeutic Hypothermia in Brain Injuries and Related Diseases

Mild or moderate hypothermia is a useful therapeutic method for improving the outcome for patients who have suffered brain injuries including traumatic brain injury and strokes, as well as secondary damages such as neuroinflammation and edema. The feasibility and safety of therapeutic hypothermia have been evaluated in experimental settings and clinical trials. Because the efficacy of therapeutic hypothermia, however, is dependent on the cooling method, application time, duration, and strategies, a continuous effort for obtaining optimal standard protocols of controlling temperature and the documentation of hypothermic devices and drugs are required. Here, we discuss the most recent hypothermia applications in brain injury and related diseases, and review the latest patents in hypothermic devices and cannabinoid-based hypothermia-inducing drugs. Ultimately, we conclude that a localized hypothermia may overcome the limitations, risks, and side effects of systemic hypothermia, and the combination of local hypothermia and drug treatment may improve clinical benefits.

Flavones from Root of Scutellaria Baicalensis Georgi: Drugs of the Future in Neurodegeneration?

Flavonoids are natural, plant-derived compounds which exert diverse biological activities, also valuable neuroprotective actions within the brain and currently are intensively studied as agents able to modulate neuronal function and to prevent age-related neurodegeneration. Among them, flavones isolated from Scutellaria baicalensis root exhibit strong neuroprotective effects on the brain and are not toxic in the broad range of tested doses. Their neuroprotective potential has been shown in both oxidative stress-induced and amyloid-β and α-synuclein – induced neuronal death models. Baicalein, the main flavone present in Scutellaria baicalensis root, strongly inhibited aggregation of neuronal amyloidogenic proteins in vitro and induces dissolution of amyloid deposits. It exerts strong antioxidative and anti-inflammatory activities and also exhibits anti-convulsive, anxiolytic, and mild sedative actions. Importantly, baicalein, and also another flavone: oroxylin A, markedly enhanced cognitive and mnestic functions in animal models of aging brains and neurodegeneration. In the preliminary study, wogonin, another flavone from Scutellaria baicalensis root, has been shown to stimulate brain tissue regeneration, inducing differentiation of neuronal precursor cells. This concise review provides the main examples of neuroprotective activities of the flavones and reveals their potential in prevention and therapy of neurodegenerative diseases.

Scientific Basis for the Use of Indian Ayurvedic Medicinal Plants in the Treatment of Neurodegenerative Disorders: 1. Ashwagandha

Ayurveda is a Sanskrit word, which means “the scripture for longevity”. It represents an ancient system of traditional medicine prevalent in India and in several other south Asian countries. It is based on a holistic view of treatment which is believed to cure human diseases through establishment of equilibrium in the different elements of human life, the body, the mind, the intellect and the soul [1]. Ayurveda dates back to the period of the Indus Valley civilization (about 3000 B.C) and has been passed on through generations of oral tradition, like the other four sacred texts (Rigveda, Yajurveda, Samaveda and Atharvanaveda) which were composed between 12th and 7th century B.C [2, 3]. References to the herbal medicines of Ayurveda are found in all of the other four Vedas, suggesting that Ayurveda predates the other Vedas by at least several centuries. It was already in full practice at the time of Buddha (6th century B.C) and had produced two of the greatest physicians of ancient India, Charaka and Shushrutha who composed the basic texts of their trade, the Samhitas. By this time, ayurveda had already developed eight different subspecialties of medical treatment, named Ashtanga, which included surgery, internal medicine, pediatrics, toxicology, health and longevity, and spiritual healing [4]. Ayurvedic medicine was mainly composed of herbal preparations which were occasionally combined with different levels of other compounds, as supplements [5]. In the Ayurvedic system, the herbs used for medicinal purposes are classed as brain tonics or rejuvenators. Among the plants most often used in Ayurveda are, in the descending order of importance: (a) Ashwagandha, (b) Brahmi, (c) Jatamansi, (d) Jyotishmati, (e) Mandukparni, (f) Shankhapushpi, and (g) Vacha. The general appearance of these seven plants is shown in Fig. (1) Their corresponding Latin names, as employed in current scientific literature, the botanical families that each of them belongs to, their normal habitats in different areas of the world, as well as the common synonyms by which they are known, are shown in the Table 1. The scientific investigations concerning the best known and most scientifically investigated of these herbs, Ashwagandha will be discussed in detail in this review. Ashwagandha (Withania somnifera, WS), also commonly known, in different parts of the world, as Indian ginseng, Winter cherry, Ajagandha, Kanaje Hindi and Samm Al Ferakh, is a plant belonging to the Solanaceae family. It is also known in different linguistic areas in India by its local vernacular names [6]. It grows prolifically in dry regions of South Asia, Central Asia and Africa, particularly in India, Pakistan, Bangladesh, Sri Lanka, Afghanistan, South Africa, Egypt, Morocco, Congo and Jordon [7]. In India, it is cultivated, on a commercial scale, in the states of Madhya Pradesh, Uttar Pradesh, Punjab, Gujarat and Rajasthan [6]. In Sanskrit, ashwagandha, the Indian name for WS, means “odor of the horse”, probably originating from the odor of its root which resembles that of a sweaty horse. The name “somnifera” in Latin means “sleep-inducer” which probably refers to its extensive use as a remedy against stress from a variety of daily chores. Some herbalists refer to ashwagandha as Indian ginseng, since it is used in India, in a way similar to how ginseng is used in traditional Chinese medicine to treat a large variety of human diseases [8]. Ashwagandha is a shrub whose various parts (berries, leaves and roots) have been used by Ayurvedic practitioners as folk remedies, or as aphrodisiacs and diuretics. The fresh roots are sometimes boiled in milk, in order to leach out undesirable constituents. The berries are sometimes used as a substitute to coagulate milk in cheese making. In Ayurveda, the herbal preparation is referred to as a “rasayana”, an elixir that works, in a nonspecific, global fashion, to increase human health and longevity. It is also considered an adaptogen, a nontoxic medication that normalizes physiological functions, disturbed by chronic stress, through correction of imbalances in the neuroendocrine and immune systems [9, 10]. The scientific research that has been carried out on Ashwagandha and other ayurvedic herbal medicines may be classified into three major categories, taking into consideration the endogenous or exogenous phenomena that are known to cause physiological disequilibrium leading to the pathological state; (A) pharmacological and therapeutic effects of extracts, purified compounds or multi-herbal mixtures on specific non-neurological diseases; (B) pharmacological and therapeutic effects of extracts, purified compounds or multi-herbal mixtures on neurodegenerative disorders; and (C) biochemical, physiological and genetic studies on the herbal plants themselves, in order to distinguish between those originating from different habitats, or to improve the known medicinal quality of the indigenous plant. Some of the major points on its use in the treatment of neurodegenerative disorders are described below.

Neuroplasticity Regulation by Noradrenaline in Mammalian Brain

The neuromodulator noradrenaline (NA) is released in almost all brain areas in a highly diffused manner. Its action is slow, as it acts through G protein-coupled receptors, but its wide release in the brain makes NA a crucial regulator for various fundamental brain functions such as arousal, attention and memory processes [102]. To understand how NA acts in the brain to promote such diverse actions, it is necessary to dissect the cellular actions of NA at the level of single neurons as well as at the level of neuronal networks. In the present article, we will provide a compact review of the main literatures concerning the NA actions on neuroplasticity processes. Depending on which subtype of adrenoceptor is activated, NA differently affects intrinsic membrane properties of postsynaptic neurons and synaptic plasticity. For example, â-adrenoceptor activation is mainly related to the potentiation of synaptic responses and learning and memory processes. á2-adrenoceptor activation may contribute to a high-order information processing such as executive function, but currently the direction of synaptic plasticity modification by á2-adrenoceptors has not been clearly determined. The activation of á1-adrenoceptors appears to mainly induce synaptic depression in the brain. But its physiological roles are still unclear: while its activation has been described as beneficial for cognitive functions, it may also exert detrimental effects in some brain structures such as the prefrontal cortex.

Electroconvulsive Therapy in Child and Adolescent Psychiatry

The efficacy and safety of Electroconvulsive therapy (ECT) in adults is well-supported by a history of robust research and clinical experience. There is less information regarding the application of this therapeutic modality for the treatment of severe psychiatric disorders in children and adolescents. However, available data suggest that ECT is a safe and effective intervention for severe mood disorders, psychosis, and catatonia in this population. The American Academy of Child and Adolescent Psychiatry (AACAP) and American Psychiatric Association (APA) have published professional guidelines for the practice of ECT in this age group. Unfortunately, child and adolescent psychiatrists typically have little training or knowledge in the practice of ECT. The authors review the historical use and current practice of this modality in minors. Further research and clinical experience is imperative in this area of child and adolescent psychiatric therapeutics.

PDE5 Inhibitors: In Vitro and In Vivo Pharmacological Profile

PDE5 inhibitors have been clearly established as first-line therapy for the treatment of erectile dysfunction (ED). Three PDE5 inhibitors – sildenafil (Viagra®), vardenafil (Levitra®) and tadalafil (Cialis®) - are currently approved by the FDA and the EMEA for use in ED, whereas sildenafil is also marketed under a different proprietary name (Revatio®) for the treatment of pulmonary arterial hypertension (PAH). A forth PDE5 inhibitor, udenafil (Zydena®), is currently marketed. In the present review the molecular basis and the mechanism of action of PDE5 inhibitors is discussed. In addition experimental and clinical data concerning their effects on different tissues, organs and systems is systematically reviewed and their possible beneficial action in numerous disorders is presented.

Effect of β-Blockers on Perioperative Myocardial Ischemia in Patients Undergoing Noncardiac Surgery

Background: Myocardial ischemia remains a major cause of morbidity in patients undergoing noncardiac surgery. The purpose of the paper was to review the evidence of the use of perioperative β-blockers for the reduction of myocardial ischemia in patients having noncardiac surgery. Method: Pubmed was searched for articles that included β-blockers and perioperative myocardial ischemia. Randomized controlled trials that assessed the effect of β-blockers on myocardial ischemia in patients undergoing noncardiac surgery were included in this review and a meta-analysis was performed. Results: Sixteen randomized controlled trials including 2230 patients were included. The study methodologies and results were summarized and meta-analysis performed. Ten trials used β-blockers in the postoperative period; 954 patients received β-blockers and 924 patients were in the control group. Of the six trials that used β-blocker for premedication, there were 207 patients in the β-blocker and 145 patients in the control group. For the cohort when β-blockers were used postoperatively, myocardial ischemia was reduced significantly with the use of β-blockers (OR 0.42; 95% CI 0.27-0.65; P=0.0001; I2=0%). A similar beneficial effect was observed in trials that used β-blocker for premedication (OR 0.16; 95% CI 0.07-0.35; P < 0.00001; I2=40%). Conclusion: The meta-analysis shows that the use of β-blockers, both as premedication and postoperatively, in noncardiac surgery is associated with a significant reduction in perioperative myocardial ischemia.

Sigma-1 Receptor Chaperones and Diseases

Chaperones are proteins that assist the correct folding of other protein clients either when the clients are being synthesized or at their functional localities. Chaperones are responsible for certain diseases. The sigma-1 receptor is recently identified as a receptor chaperone whose activity can be activated/deactivated by specific ligands. Under physiological conditions, the sigma-1 receptor chaperones the functional IP3 receptor at the endoplasmic reticulum and mitochondrion interface to ensure proper Ca2+ signaling from endoplasmic reticulum into mitochondrion. However, under pathological conditions whereby cells encounter enormous stress that results in the endoplasmic reticulum losing its global Ca2+ homeostasis, the sigma-1 receptor translocates and counteracts the arising apoptosis. Thus, the sigma-1 receptor is a receptor chaperone essential for the metabotropic receptor signaling and for the survival against cellular stress. The sigma-1 receptor has been implicated in many diseases including addiction, pain, depression, stroke, and cancer. Whether the chaperone activity of the sigma-1 receptor attributes to those diseases awaits further investigation.

Toll-Like Receptors and Myocardial Ischemia/Reperfusion, Inflammation, and Injury

Cardiac ischemia/reperfusion (I/R) injury occurs in several important clinical contexts including percutaneous coronary interventions for acute myocardial ischemia, cardiac surgery in the setting of cardiopulmonary bypass, and cardiac transplantation. While the pathogenesis of I/R injury in these settings is multifactorial, it is clear that activation of the innate immune system and the resultant inflammatory response are important components of I/R injury. Toll-like receptor 4 (TLR4), originally identified as the sensor for bacterial lipopolysaccharide (LPS), has also been shown to serve as a sensor for endogenous molecules released from damaged or ischemic tissues. Accordingly, recent findings have demonstrated that TLR4 not only plays a central role as a mediator of cardiac dysfunction in sepsis, but also serves as a key mediator of myocardial injury and inflammation in the setting of I/R. Furthermore, TLR4 may play a role in the development of atherosclerotic lesions. Other studies have implicated TLR4 in the adverse remodeling that may occur after ischemic myocardial injury. This emerging body of literature, which is reviewed here, has provided new insight into the early molecular events that mediate myocardial injury and dysfunction in the setting of I/R injury.

Dexmedetomidine Use in General Anaesthesia

Dexmedetomidine is a potent and highly selective α2-adrenoreceptor agonist currently utilized for continuous infusion for sedation/analgesia in the intensive care unit (ICU). Dexmedetomidine offers remarkable pharmacological properties including sedation, anxiolysis, and analgesia with the unique characteristic to cause no respiratory depression. In addition it posses sympatholytic and antinociceptive effects that allow hemodynamic stability during surgical stimulation. Different from most of clinically used anesthetics, dexmedetomidine brings about not only a sedativehypnotic effect via an action on a single type of receptors, but also an analgesic effect and an autonomic blockade that is beneficial in cardiac risk situations. Several studies have demonstrated its safety, although bradycardia and hypotension are the most predictable and frequent side effects. Dexmedetomidine has shown to consistently reduce opioids, propofol, and benzodiazepines requirements. In the last years it has emerged as an affective therapeutic drug in a wide range of anesthetic management, promising large benefits in the perioperative use. In particular this review focuses on dexmedetomidine utilization in premedication, general surgery, neurosurgery, cardiac surgery, bariatric surgery, and for procedural sedation and awake fiberoptic intubation. In all these fields dexmedetomidine has demonstrated to be an efficacious and safe adjuvant to other sedative and anesthetic medications.

Clonidine in Perioperative Medicine and Intensive Care Unit: More Than An Anti-Hypertensive Drug

Clonidine is classified as an imidazoline and it is the prototypical alpha-2 receptor agonists. It has been used for several years to treat hypertension. It has also been used, “off label”, for a variety of purposes, including opioid and anesthetic sparing effects, anxiolysis and sedation, drug withdrawal as well as stabilizing blood pressure and reducing stress response to surgery. Particularly in the case of patients with overt or underlying cardiac disease and in those at risk of perioperative ischemia the action of clonidine can be expected to reduce the risk of procedure-related cardiac events. In addition, clonidine used as a premedication drug before surgery or surgical procedure, has been shown to substantially reduce anaesthetic, benzodiazepine and opioids requirements. However, its “off label” use, the absence of an intravenous form of in the United States, possible inadvertent hypotension, bradycardia or post-operative sedation, and the variability of the haemodynamic response to different doses or rates of administration, have limited its use in clinical practice. This review discusses the potential role of clonidine and the supporting evidence for the use of this drug beyond its antihypertensive use in perioperative medicine and critical care in adults patients.

Neuro-Transmitters in the Central Nervous System & their Implication in Learning and Memory Processes

This review article gives an overview of a number of central neuro-transmitters, which are essential for integrating many functions in the central nervous system (CNS), such as learning, memory, sleep cycle, body movement, hormone regulation and many others. Neurons use neuro-transmitters to communicate, and a great variety of molecules are known to fit the criteria to be classified as such. A process shared by all neuro-transmitters is their release by excocytosis, and we give an outline of the molecular events and protein complexes involved in this mechanism. Synthesis, transport, inactivation, and cellular signaling can be very diverse when different neuro-transmitters are compared, and these processes are described separately for each neuro-transmitter system. Here we focus on the most well known neurotransmitters: acetyl-choline, catechol-amines (dopamine and nor-adrenalin), indole-amine (serotonin), glutamate, and γ- amino-butyric acid (GABA). Glutamate is the major excitatory neuro-transmitter in the brain and its actions are counterbalanced by GABA, which is the major inhibitory substance in the CNS. A balance of neuronal transmission between these two neuro-transmitters is essential to normal brain function. Acetyl-choline, serotonin and catechol-amines have a more modulatory function in the brain, being involved in many neuronal circuits. Apart from summarizing the current knowledge about the synthesis, release and receptor signaling of these transmitters, some disease states due to alteration of their normal neuro-transmission are also described.

The Valsalva Maneuver and Alzheimers Disease: Is there a link?

Recent research findings provide evidence for Alzheimers disease-related changes in brain diseases, such as normal pressure hydrocephalus and traumatic brain injury, and in glaucoma at the level of the retinal ganglion cells. This is a group of diseases that affect central nervous system tissue and are characterized by elevation of intracranial or intraocular pressure and/or local shear stress and strain. This strengthens the possibility that Alzheimer-type changes in these diseases may result at least in part from exposure of central nervous system tissue to elevated mechanical load. As activities or diseases with significant Valsalva effort can generate increased intracranial pressures, we hypothesize that individuals who frequently perform strong Valsalva maneuvers (e.g., long hours of repetitive heavy lifting, sequences of blows during the playing of a wind instrument, forceful and repetitive cough, bearing-down efforts during parturition) may be more susceptible to developing Alzheimers disease. In this paper, we discuss three hypotheses about the mechanisms by which extensive use of the Valsalva maneuver might contribute to the neuropathogenesis of Alzheimers disease: via mechanical stress-induced events in the hippocampus and/or via changes in the secretory process of the choroid plexus and/or via hemodynamic changes in cerebral blood flow. If confirmed, this hypothesis could have implications in clinical practice.

Visuospatial Memory in Healthy Elderly, AD and MCI: A Review

In the literature it is commonly reported that several spatial abilities decline with normal aging, even though such a decline is not uniform. So far, it is not yet clear which spatial components present a normal age-related decline, which ones are preserved and at what point the deficit is so severe to represent an index of mild cognitive impairment (MCI) or a symptom of potential degenerative progression as in the early-stage Alzheimers disease (AD). In particular, AD (from early onset) is characterised by impairments in constructive abilities, visuospatial intelligence, spatial shortterm memory deficits, and disorders of spatial orientation (topographical disorientation). MCI indicates a condition, generally affecting older individuals, characterized by cognitive deficits including memory and/or non memory impairments and at high risk of progression to dementia. Three MCI subgroups have been distinguished and a very high risk of developing AD is associated to the amnestic MCI subtypes. Further, recent studies have suggested that the allocentric component of spatial memory might be taken as predictor of AD from MCI. Given the frequency of visuospatial deficits in early-stage AD, evaluation of visuospatial processes is a promising approach to find predictive markers of AD. Here we report a review of the literature exploring specific visuospatial components in normal aging, MCI, and AD. In this way we could shed some light on the role of these components in the progression from MCI to AD and pave the way for future studies.