Objectives: The aim of this study was to partially purify and characterize the antifungal activity of a defensin-enriched fraction (F3) from Capsicum chinense fruits. Specifically, we sought to evaluate its efficacy against pathogenic fungi and yeasts, and to assess the relative abundance of defensins in the fraction.

Methods: The F3 fraction was obtained using ion exchange and molecular exclusion chromatography. Reverse-phase chromatography (HPLC) was then employed for further purification. The antifungal activity of F3 was tested against Colletotrichum, Fusarium, and Candida species. Mass spectrometry was used to identify and characterize the defensin (CcDef3) within the fraction. The presence of the defensin relative to other components was inferred from electrophoretic profiles and peptide analysis.

Results: The F3 fraction exhibited significant antifungal activity, with growth inhibition of Colletotrichum lindemuthianum of 51% and 60.9% at concentrations of 100 and 200 μg mL-1, respectively. The fraction also inhibited the growth of several Candida species, notably C. nivariensis (93.8%) and C. bracarensis (79.6%) at 100 μg mL-1. Cell viability analysis indicated a fungistatic effect. Fluorescence microscopy assays showed that F3 induced membrane permeabilization in C. parapsilosis and C. lindemuthianum, and increased ROS production in C. pelliculosa and F. solani. The defensin-rich H8 fraction, containing a 6.5 kDa protein (CcDef3), was identified as a major component via mass spectrometry.

Discussion: The ongoing development of resistance in fungal strains, particularly Candida species, against traditional antibiotics and antifungals has turned into a significant medical concern and has increased the need for new treatment options.

Conclusion: These results suggest that the F3 fraction, particularly the defensin CcDef3, has potential as an antifungal agent for biotechnological and therapeutic applications. However, further studies are needed to quantify the contribution of CcDef3 relative to other components in the fraction and to fully isolate the defensin for in-depth analysis.

Methods: To investigate this hypothesis, immunoinformatics tools were employed to identify overlapping CD4, CD8, and B-cell epitopes shared between Mycobacteria and SARS-CoV-2. The most promising CD8 epitope was synthesized using the SPPS-Fmoc method, and antigen-specific Tcell proliferation was evaluated by CFSE dye-dilution assay. Additionally, the expression of proand anti-inflammatory molecules was assessed using qRT-PCR.

Results: Multiple overlapping T-cell and B-cell epitopes were identified between Mycobacteria and SARS-CoV-2. The T-cell epitopes displayed promiscuous binding characteristics, high immunogenicity, and strong affinity for both HLA class I and class II alleles. Experimental validation using the most immunodominant T-cell epitope confirmed its ability to induce proliferation and differentiation of T cells isolated from COVID-19-vaccinated individuals.

Discussion: The overlapping T-cell and B-cell epitopes identified through this approach may provide broader and more robust protection than initial exposure to virus-specific antigens, which the immune system encounters for the first time during infection or vaccination. This strategy may therefore support the rapid and effective development of future vaccines, particularly against emerging pathogens.

Conclusion: The findings suggest that the higher level of protection observed in TB-endemic countries during recent pandemics may be attributable to cross-reactive mycobacterial antigens that stimulate protective immunity.

Methods: An AILI model was established in male C57BL/6 mice via intraperitoneal (i.p.) injection of APAP (300 mg/kg). The therapeutic potential of MOTS-c and its mechanisms were assessed using behavioral tests, qPCR, western blotting, ELISA, immunohistochemistry, immunofluorescence, and TUNEL staining.

Results: MOTS-c levels in both plasma and liver tissues were significantly reduced in APAPinduced AILI mice compared with controls. Administration of MOTS-c via i.p. injection markedly attenuated APAP-induced increases in AST and ALT levels, histopathological liver damage, and other liver injury markers. MOTS-c treatment suppressed the release of pro-inflammatory factors (TNF-α, IL-1β, IL-6, and COX-2) and macrophage infiltration induced by APAP. Furthermore, MOTS-c treatment significantly restored GSH content, diminished reactive oxygen species (ROS) production, and oxidative stress. TUNEL staining confirmed that increased apoptosis in APAPtreated livers was significantly attenuated by MOTS-c, which are key contributors to hepatocyte death and liver injury. Mechanistic studies revealed that MOTS-c inhibited APAP-induced phosphorylation of MAPK pathway components, including ERK, JNK, and p38. The protective effects of MOTS-c on serum ALT and AST levels were abolished by co-treatment with inhibitors of ERK, JNK, and p38.

Discussion: This study reveals that the mitochondrial peptide MOTS-c can alleviate drug-induced liver injury by suppressing oxidative stress and inflammation via the MAPK pathway. This positions MOTS-c as a promising therapeutic candidate for treating APAP-induced liver injury.

Conclusion: This study demonstrates that administering MOTS-c effectively protects against APAP-induced liver injury in mice. The protective mechanism involves suppressing the damaging MAPK signaling pathway (ERK, JNK, p38), which in turn reduces oxidative stress, inflammation, and cell death.]]> https://www.benthamscience.com/article/1541672026-04-01 Introduction: Rising demand for natural bioactive compounds has increased interest in underutilized animal proteins, with sarcoplasmic muscle proteins showing potential for functional peptide production. This study aimed to evaluate the antioxidant and antibacterial activities of sarcoplasmic protein hydrolysates from IPB-D1 chicken, a dual-purpose Indonesian line.

Methods: Sarcoplasmic proteins were hydrolyzed with chymotrypsin, ultrafiltered (MWCO ≤3 kDa), and analyzed for antioxidant and antibacterial activities.

Results: Hydrolysates (SHF) showed a sharp decrease in protein concentration (from 49.86 ± 6.19 mg to 0.79 ± 0.05 mg) and disappearance of SDS-PAGE bands, confirming breakdown into smaller peptides. Antioxidant activity increased significantly in SHF compared with the unhydrolyzed fraction (SF). In antibacterial tests, SHF produced larger inhibition zones for all tested bacteria, with the strongest against S. typhi (2.20 ± 1.27 mm) and B. cereus (2.13 ± 0.99 mm), and the lowest against S. aureus (0.36 ± 0.06 mm). Gram-positive bacteria were generally more susceptible than Gram-negative bacteria.

Discussion: These results suggest that enzymatic hydrolysis and size reduction (<3 kDa) enhance bioactivity by increasing peptide accessibility and interaction with bacterial membranes. The higher sensitivity of Gram-positive strains is likely related to simpler cell wall structures.

Conclusion: IPB-D1 chicken sarcoplasmic hydrolysates are a promising source of multifunctional peptides with antioxidant and antibacterial activities. This highlights the potential of IPB-D1 not only as a meat source but also as a strategic genetic resource for sustainable bioprocessing and functional food innovation.]]> https://www.benthamscience.com/article/1538712026-04-01 Introduction: Polystyrene microplastics (PS-MPs) contribute to cardiovascular pathologies by inducing vascular endothelial injury through oxidative stress and inflammation. This study aimed to investigate the protective role of apricot kernel peptide extract (AKPE) against PS-MPs- induced damage in human aortic endothelial cells (HAECs) and to elucidate the underlying molecular mechanisms.

Methods: AKPE was isolated from apricot kernels using an activity-guided fractionation approach based on its protective efficacy in HAECs exposed to PS-MPs. Cytotoxicity and dose-response experiments established an optimal concentration of 20 μM. Subsequent analyses included cell viability (CCK-8 assay), intracellular reactive oxygen species (ROS) and superoxide dismutase (SOD) activity, inflammatory cytokine levels (α, IL-1β, IL-18) via ELISA, apoptosis assessment by flow cytometry, and evaluation of mitochondrial function. Bioactive oligopeptides within AKPE were identified by mass spectrometry. The involvement of the NLRP3 inflammasome and Wnt/β-catenin signaling pathways was examined using Western blotting and quantitative PCR.

Results: AKPE significantly counteracted the PS-MPs-induced reduction in HAEC viability, increasing it by 16.2% (p < 0.01). It also reduced intracellular ROS levels by 35.1% (p < 0.01) while preserving SOD activity. Furthermore, AKPE suppressed the production of pro-inflammatory cytokines (TNF-α, IL-1β, IL-18) by 17–38% (p < 0.01). PS-MPs-induced mitochondrial dysfunction and apoptosis were markedly attenuated, with a 39.1% decrease in apoptotic cells (p < 0.01). Mass spectrometry identified eight key oligopeptides as the primary bioactive constituents of AKPE. Mechanistically, these components acted synergistically to inhibit NLRP3 inflammasome activation and to modulate the dysregulated Wnt/β-catenin pathway.

Discussion: AKPE protects HAECs from PS-MPs-induced damage through dual mechanisms: (1) suppressing NLRP3 inflammasome-driven inflammation and (2) mitigating oxidative stress via Wnt/β-catenin pathway inhibition. The synergy among AKPE peptides enhances resilience against PS-MPs, highlighting their potential as natural antioxidants. This study is the first to link apricot kernel peptides to PS-MPs-induced endothelial protection, providing novel insights into combating microplastic-related cardiovascular risks.

Conclusion: AKPE exerts potent protective effects against oxidative and inflammatory injury in HAECs caused by PS-MPs. These effects are mediated by its constituent bioactive oligopeptides, which concurrently regulate the NLRP3 inflammasome and Wnt/β-catenin signaling pathways. Our findings highlight AKPE's potential as a promising natural therapeutic agent for alleviating vascular endothelial damage associated with microplastic exposure.

Materials and Methods: To fill this gap, the study used quantitative acetyl-proteomics to track changes in the lysine acetylome during THP-1 monocyte differentiation into macrophages following ASA preconditioning.

Results: Our results showed that preconditioning of THP-1 macrophages with 300 μg/ml ASA for 3 hours before differentiation induced persistent acetylation changes. We identified 5,199 differentially acetylated sites across 2,678 proteins, with 2,595 sites upregulated and 2,604 downregulated. The sequence analysis revealed a strong preference of ASA for acidic residues like E_K motifs and hydrophobic regions. The subcellular localization analysis showed notable enrichment in the nucleus (1,166 proteins), cytoplasm (850 proteins), and mitochondria (405 proteins), and frequently contained functional domains like PWWP, SET, RhoGEF, and RNA recognition motifs.

Discussion: The Gene Ontology analysis linked these proteins to cellular metabolism, regulation, and stimulus response, while our KEGG analysis connected them to neurodegeneration, infection, and metabolic pathways. Furthermore, the protein-protein interaction networks further showed coordinated changes in ribosomal, signaling, and chromatin complexes.

Conclusion: The findings show that ASA preconditioning leaves a lasting acetylome signature during macrophage differentiation reprogramming regulatory networks relevant to macrophage differentiation and functional networks via motif-directed acetylation. The results provide a plausible COX-independent model in which structural motif-targeted acetylation may underlie ASA’s immunomodulatory role.]]> https://www.benthamscience.com/article/1531792026-04-01 Introduction: Mitochondrial redox homeostasis is of utmost significance in myocardial ischemia-reperfusion (I/R) injury. Irisin, a myokine, has drawn extensive attention in research regarding the protection against cardiovascular diseases.

Methods: This study utilized in vitro Hypoxia/Reoxygenation (H/R) models in H9c2 cardiomyocytes to simulate I/R injury. Cells were pretreated with irisin (20 ng/mL) prior to reoxygenation. UCP2 knockdown was achieved via siRNA/shRNA transfection. Cell viability and apoptosis were assessed using CCK-8 and flow cytometry (Annexin V-FITC/PI staining), respectively. Intracellular calcium dynamics were monitored by Fluo-3/AM confocal imaging, while ROS levels were quantified via DCFH-DA flow cytometry. Key oxidative stress markers (LDH, MDA, GSH-Px, and CAT) and protein expression (ASC, NLRP3, SIRT1, UCP2, and SOD2) were evaluated using commercial kits and Western blotting. Protein interactions were analyzed by coimmunoprecipitation, and ubiquitination levels were measured under proteasomal/lysosomal inhibition (MG132/Leupeptin).

Results: Irisin attenuated H/R injury in cardiomyocytes by suppressing apoptosis, calcium/ROS overload, and NLRP3 activation through a UCP2-dependent pathway. UCP2 knockdown significantly attenuated irisin’s protection and reduced SOD2 protein stability. Mechanistically, UCP2 bound SOD2 and inhibited its ubiquitin-proteasomal degradation.

Discussion: This study reveals a novel mechanism where irisin enhances mitochondrial redox homeostasis by promoting UCP2’s function, which stabilizes SOD2 against ubiquitin-proteasomal degradation. This UCP2-SOD2 axis attenuates oxidative stress and inhibits NLRP3 inflammasome activation during cardiac injury, offering a promising dual-targeted therapeutic strategy for I/R injury.

Conclusion: Irisin protects cardiomyocytes against H/R injury primarily via a novel UCP2-SOD2 axis.]]> https://www.benthamscience.com/article/1541592026-04-01 Introduction/Objectives: The 3-chymotrypsin-like protease (3CLpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for viral replication and is catalytically active only in its dimeric form. Elucidating the molecular determinants that stabilize this dimer may uncover novel antiviral drug targets. This study aimed to characterize the oligomerization behavior of wild-type 3CLpro and to elucidate the functional role of an alanine– valine zipper motif in dimer stability and enzymatic activity.

Methods: Wild-type 3CLpro (3CLpro-WT) was heterologously expressed in Escherichia coli BL21(DE3) and purified by nickel-affinity chromatography. Oligomerization behavior was examined using Size-Exclusion Chromatography (SEC) under varying protein concentrations, pH conditions, and ionic strengths. An alanine–valine zipper mutant (A7G/V125G; 3CLpro-ZM) was generated by site-directed mutagenesis, overexpressed, purified using the same protocol, and analyzed for changes in folding, oligomerization, and enzymatic activity.

Results: 3CLpro-WT predominantly existed as a stable dimer, independent of protein concentration and ionic strength, but was destabilized under extreme pH conditions. In contrast, 3CLpro-ZM exhibited a perturbed dimerization equilibrium, altered secondary structure, and a pronounced reduction in both protease and esterase activities compared with the wild-type enzyme.

Discussion: These findings demonstrate that hydrophobic interactions are the primary force stabilizing the 3CLpro dimer, while ionic interactions provide pH-sensitive modulation. Disruption of the alanine–valine zipper compromises dimer integrity and allosterically impairs catalytic activity, despite the mutation being distant from the active site.

Conclusion: The Ala7–Val125 interface contributes to 3CLpro stability and activity and may be a promising site for future allosteric inhibitor design.]]> https://www.benthamscience.com/article/1527382026-04-01 After publication, the publisher noted that reference 16 was missing from the text of article [1]. This has now been corrected.

The original article can be found online at: https://www.benthamscience.com/article/150920 Details of the error and a correction are provided here.

Original:

These peptides comprise between 40 and 70 percent hydrophobic amino acids and are abundant in positively charged amino acids, such as histidine, arginine, and lysine [15].

Corrected:

These peptides comprise between 40 and 70 percent hydrophobic amino acids and are abundant in positively charged amino acids, such as histidine, arginine, and lysine [15,16].

The original article can be found online at: https://www.benthamscience.com/article/152908

Details of the errors and the corrections are provided here.

Original:

When calculating properties related to this function, such as the interaction energy between ligand and receptor in docking, instead of using the entire Cartesian space, the computational effort is substantially reduced since only the grid points are used for these calculations [14]. (https://doi.org/10.1002/jcc.21256).

Corrected:

When calculating properties related to this function, such as the interaction energy between ligand and receptor in docking, instead of using the entire Cartesian space, the computational effort is substantially reduced since only the grid points are used for these calculations [14].