Current Aging Science
ISSN: 1874-6098 (Print)
ISSN: 1874-6128 (Online)
Current Aging Science
Volume 2, Number 1, February 2009
Contents
Editorial:
Progress and Vision for ‘Current Aging Science’
Pp. 1-2
Debomoy K. Lahiri
Does Aging Stop?Pp. 3-11
Parvin Shahrestani, Laurence D. Mueller
and Michael R. Rose
[Abstract] [Full Text Article]
Mitochondria, Cellular Stress Resistance,
Somatic Cell Depletion and LifespanPp.
12-27
Ellen L. Robb, Melissa M. Page and
Jeffrey A. Stuart
[Abstract] [Full Text Article]
The Association of Very High Hair Manganese
Accumulation and High Oxidative Stress in Mongolian PeoplePp. 28-42
Fumio Komatsu, Yasuo Kagawa, Kiyomi Ishiguro,
Terue Kawabata, Baatar Purvee, Jugder Otgon and Ulziiburen
Chimedregzen
[Abstract] [Full Text Article]
Visuospatial Memory in Healthy Elderly,
AD and MCI: A Review Pp. 43-59
Tina Iachini, Alessandro Iavarone, Vincenzo
Paolo Senese, Francesco Ruotolo and Gennaro Ruggiero
[Abstract] [Full Text Article]
Greater Specificity of Sensorimotor Learning
in the Elderly when Acquiring an Interceptive TaskPp.
60-66
Luis Augusto Teixeira and Elke
dos S. Lima
[Abstract] [Full Text Article]
Effect of Gender on Main Clinical Chemistry
Parameters in Aged RatsPp. 67-71
Refik Kayali, Seval Aydin and Ufuk
Çakatay
[Abstract] [Full Text Article]
The Use of Sensory Nerve Stimulation
and Compression Bandaging to Improve Sensory Nerve Function
and Healing of Chronic Venous Leg UlcersPp.
72-80
Rajna Ogrin, Peteris Darzins and Zeinab
Khalil
[Abstract] [Full Text Article]
Acknowledgment
to the Reviewers Pp. 81
Abstracts
[Back to top]
Does Aging Stop?
Parvin Shahrestani, Laurence D. Mueller and Michael
R. Rose
[Full Text Article]
Human mortality data show stabilization in mortality
rates at very late ages. But human mortality data are difficult
to interpret because they are affected by changing medical
practices and other historically variable causes of death.
However, in the 1990s, data from a variety of labs showed
that the mortality rates of medflies, fruit flies, wasps,
yeasts, and nematodes also stabilize at very late ages. These
reproducible “mortality-rate plateaus” forced
biologists to develop theories for their existence. There
are two main theories of this kind. “Lifelong heterogeneity”
theories suppose that highly robust subcohorts are more abundant
at later ages because less robust subcohorts have mostly died
off. On this type of theory, aging does not stop; aging continues
inexorably in all individuals. In contrast, in evolutionary
theories for mortality-rate plateaus, based on the eventual
plateaus in Hamilton’s Forces of Natural Selection at
late ages, aging does indeed stop. A variety of experiments
have cast doubt on lifelong heterogeneity theories as explanations
of mortality-rate plateaus. A few experiments have corroborated
the Hamiltonian theory. This has the important corollary that
it appears to be possible for aging to stop, at sufficiently
late ages, at least among some populations. The implications
of this result for aging research are profound. Most importantly,
it suggests the possibility that the physiology of adults
undergoing aging may be substantially different from the physiology
of life after aging.
[Back to top]
Mitochondria, Cellular Stress Resistance, Somatic
Cell Depletion and Lifespan
Ellen L. Robb, Melissa M. Page and
Jeffrey A. Stuart
[Full Text Article]
The causes of aging and determinants of maximum lifespan
in animal species are multifaceted and complex. However, a
wealth of experimental data suggests that mitochondria are
involved both in the aging process and in regulating lifespan.
Here we outline a somatic cell depletion (SCD) model to account
for correlations between: (1) mitochondrial reactive oxygen
species and lifespan; (2) mitochondrial antioxidant enzymes
and lifespan; (3) mitochondrial DNA mutation and lifespan
and (4) cellular stress resistance and lifespan. We examine
the available data from within the framework of the SCD model,
in which mitochondrial dysfunction leading to cell death and
gradual loss of essential somatic cells eventually contributes
to the decline in physiological performance that limits lifespan.
This model is useful in explaining many of the mitochondrial
manipulations that alter maximum lifespan in a variety of
animal species; however, there are a number of caveats and
critical experiments outstanding, and these are outlined in
this review.
[Back to top]
The Association of Very High Hair Manganese Accumulation
and High Oxidative Stress in Mongolian People
Fumio Komatsu, Yasuo Kagawa, Kiyomi Ishiguro,
Terue Kawabata, Baatar Purvee, Jugder Otgon and Ulziiburen
Chimedregzen
[Full Text Article]
Oxidative stress induces several diseases and early
aging. Previously, we reported that Mongolians are exposed
in high oxidative stress, which may cause their early aging.
In this study, to know the reason of high oxidative stress,
we measured hair metals. This investigation was performed
in Murun city, in the northern area of this country, and 469
healthy subjects, ranging from 10 to 82 years of age, were
randomly enrolled. Oxidative stress was evaluated by the levels
of serum reactive oxygen metabolites (ROM), malondialdehyde-modified
low-density lipoprotein (MDA-LDL) and urinary 8-hydroxy-2'-deoxyguanosine
(8-OHdG). Antioxidant capacity (AOC) was estimated by the
levels of biological antioxidant potential (BAP) and superoxide
dismutase (SOD) activity. Scalp hair metals were measured
using an inductively coupled plasma mass spectrometry method.
Murun subjects showed high ROM levels of 394±75
Carr U (n=342), compared with Japanese healthy subjects (n=356,
326±51 Carr U, p<0.001).
MDA-LDL and 8-OHdG levels also showed high levels. While,
BAP levels of Murun subjects were 2263±203µmol/L
(n=210), Japanese subjects (n=356, 2087±215µmol/L,
p<0.001).
SOD activities were also high, suggesting that the high oxidative
may accelerate the state of AOC. Murun subjects demonstrated
high accumulation of several metals in the hairs. In particular,
Mn accumulation exhibited from 2 fold to 40 fold increases
of Japanese standard. These findings are indicative that the
high Mn accumulation may contribute to the high oxidative
stress. The mechanism of its high accumulation was not explained
by food materials or drinking water. We should further investigate
another influence such as sandy wind. In order to suppress
the high oxidative stress, elimination of the high Mn accumulation
should be urgently studied.
[Back to top]
Visuospatial Memory in Healthy Elderly, AD and MCI:
A Review
Tina Iachini, Alessandro Iavarone, Vincenzo
Paolo Senese, Francesco Ruotolo and Gennaro Ruggiero
[Full Text Article]
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 Alzheimer’s disease (AD). In particular,
AD (from early onset) is characterised by impairments in constructive
abilities, visuospatial intelligence, spatial short-term 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.
[Back to top]
Greater Specificity of Sensorimotor Learning in the
Elderly when Acquiring an Interceptive Task
Luis Augusto Teixeira and Elke dos S. Lima
[Full Text Article]
In this investigation we assessed the extent to which
young and elderly individuals become dependent on the specific
visual situation present during practice of an interceptive
task. Young and elderly participants practiced extensively
a task of intercepting a virtually moving target under full
vision or visual occlusion of the last 600 ms of target displacement.
Before and after practice they were assessed in four visual
conditions varying the time interval of visual display. The
results showed that the elderly practicing under full vision
had a progressive increase of temporal errors as a function
of the period of visual occlusion after task acquisition.
The elderly practicing under visual occlusion, conversely,
achieved improved performance only in the visual condition
experienced during task acquisition. Young individuals showed
greater adaptability, presenting similar performance across
visual conditions. Development of specific visuomotor integration
only for the elderly seems to be related with the higher status
that vision holds for movement control at this age.
[Back to top]
Effect of Gender on Main Clinical Chemistry Parameters in
Aged Rats
Refik Kayali, Seval Aydin and Ufuk Çakatay
[Full Text Article]
Introduction: Clinical laboratory data are crucially
important for the diagnosis, prognosis and therapy of aging-related
diseases. The age-dependent changes in the findings of routine
clinical-chemistry analyses may influence the evaluation of
health status of the elderly people. Serum endogenous antioxidant
levels and lipid profiles are considered to be related to
the progress of age-related diseases. Analyses of these routine
parameters are also important for the evaluation in the elderly.
Although the analyses of serum biochemical parameters are
important, there have been not enough data on changes in the
levels of parameters with aging in both genders. However,
elderly people generally suffer from aging-related diseases
or may be using some medication that interferes with the accuracy
of the result; it is thus preferred that the same procedures
be applied in aged rats as a model of human aging.
Methods: Aged Sprague-Dawley rats (24 months) of
both genders were used in the current study. Serum total protein,
albumin, bilirubin, uric acid, lipid profiles, iron, and total
iron-binding capacity levels were determined on the same day
of collection by standard clinical chemistry laboratory methods.
Results: Serum endogenous antioxidant parameters
such as uric acid and bilirubin levels varied with gender
in spite of almost no changes in the serum albumin and total
iron binding capacity levels. Among the main parameters studied,
lipid profile, conjugated bilirubin, and uric acid levels
of male rats were significantly higher than in the aged female
group. On the other hand, serum unconjugated bilirubin and
iron levels were all found to be lower in the aged male group.
Conclusion: Our findings support our conviction that
serum biochemical parameters of aged rats have a controlling
role in differing regulating mechanisms through gender differences.
The gender-related data on these main serum clinical chemistry
parameters in aged rats would be useful in studies of aging-related
disorders using this model.
[Back to top]
The Use of Sensory Nerve Stimulation and Compression
Bandaging to Improve Sensory Nerve Function and Healing of
Chronic Venous Leg Ulcers
Rajna Ogrin, Peteris Darzins and Zeinab
Khalil
[Full Text Article]
Low frequency transcutaneous sensory nerve stimulation
(LF-SNS) [International Patent PCT/AU2004/001079:"nerve
function and tissue healing" (Khalil, Z.)] improves sensory
nerve function and accelerates wound healing of older animals.
Intervention: Double blind, placebo
controlled randomised trial of LF-SNS for 5 minutes, twice
daily for up to 12 weeks, on healing of chronic venous leg
ulcers in older people. Four layer compression bandaging was
the standard therapy.
Outcome measures (methods): Wound healing and the
rate of epithelialisation (calculated from serial wound area
estimation), microvascular blood flow (measured using LASER
Doppler flowmetry), transcutaneous oxygen tension (measured
using a transcutaneous oxygen monitor, TCM™400
Radiometer). Sensory nerve activity (assessed via
measuring electrical cutaneous perception threshold using
the Neurometer®CPT
and the flare response to 5% capsaicin (a selective activator
of C fibres).
Participants: 14 older people with chronic venous
ulcers randomly allocated to active (mean age 74.8±2.3
years) and 15 to Sham nerve stimulation (mean age 76.5±2.6
years).
Results: Microvascular blood flow improved in all
participants. A high proportion of wounds healed (~ 60%).
There were trends for better C-fibre function and faster healing
rates in the Active group (1.1±0.3
cm2/wk) compared to the Sham
group (0.6±0.2
cm2/wk) but failed to reach
statistical significance due to the small sample size.
Conclusions: The improvement in microvascular blood
flow in both groups was an unexpected finding that has not
previously been described. Most likely this was due to the
four layer compression bandaging provided to all participants.
Improved microvascular blood flow may be a significant contributor
to wound healing. The observed trends to increased healing
rates and improvements in C-fibre function in the actively
stimulated group compared to the sham group warrant further
studies of LF-SNS as an adjunct therapy for chronic venous
leg ulcers. An exploration of the possibility that LF-SNS
induced-improvement in C-fibre function could protect against
future ulceration is also warranted.
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