Search Results (1,632)

Hypertension is a major risk factor for heart failure. Acetylation of p53 is known to regulate its activities. We have previously identified that p53 acetylation is required for cardiac remodeling in a mouse model of pressure overload-induced heart failure. Acetylation mutant p53 (p53aceKO) mice have been shown to have the ability to regulate SIRT3 KO-induced cardiac fibrosis. In the present study, we hypothesized that p53aceKO mice would exhibit cardiac protection and blunt cardiac fibrosis when subjected to Ang-II-induced hypertension. Control and p53aceKO mice received either a micro-osmotic pump implant administering Ang-II for 28 days or a sham procedure. Blood pressure was measured weekly, and echocardiography was performed every two weeks. Mice were euthanized and hearts were processed for histological analysis. While both control and p53aceKO mice receiving Ang-II exhibit increased systolic and diastolic blood pressures, control mice also demonstrate increases in ejection fraction and fractional shortening compared to the sham, while p53aceKO mice do not. Furthermore, control mice receiving Ang-II exhibit decreased left ventricular diameter and volume at end-systole and end-diastole, as well as thickening of both the anterior and posterior walls, while p53aceKO mice exhibit no significant changes in any of these parameters. Additionally, p53aceKO mice do not exhibit the Ang-II infusion-induced cardiac fibrosis seen in control mice treated with Ang-II. Mutation of p53 acetylation is protective against Ang-II infusion-induced cardiac fibrosis and dysfunction in mice. Acetylated p53 may, therefore, be a novel therapeutic target to address complications in the heart associated with hypertension. Full article

Sirtuins (SIRT1–SIRT7) are NAD⁺-dependent deacetylases that link cellular energy status to chromatin maintenance, mitochondrial function and inflammatory signaling. While modulation of SIRT1, SIRT3 and SIRT6 extends lifespan in model organisms, evidence in extreme-age humans is scarce. We quantified protein and mRNA levels, and protein-to-mRNA ratios for SIRT1, SIRT3 and SIRT6 in buccal epithelial cells obtained from healthy young adults, middle/late-aged individuals and nonagenarians/centenarians residing in a longevity-enriched region of south-eastern Azerbaijan. The cohort comprised 23 participants, stratified by sex and cardiovascular disease (CVD) status (5 per sex/CVD subgroup). This design allows us to: (1) define a baseline “sirtuin profile” of healthy longevity, (2) evaluate the impact of CVD as a prevalent age-related pathology, and (3) explore potential sex-specific modulation. These findings establish an initial human framework linking sirtuin translational control to healthy ageing and cardiovascular health. Full article

Background/Objectives: Aging is characterized by progressive physiological and metabolic decline. Aerobic exercise mitigates age-related impairments, and nicotinamide mononucleotide (NMN), a precursor in the NAD⁺ salvage pathway, has emerged as a nutritional intervention to promote healthy aging. This study investigated whether NMN supplementation combined with aerobic exercise provides synergistic benefits on physical performance and metabolic regulation in aged mice. Methods: Forty male C57BL/6J mice, including eight young (8 weeks) and thirty-two aged (85 weeks) mice, were randomly assigned to five groups: young sedentary (YS), aged sedentary (AS), aged with exercise (AE), aged with NMN (ASNMN; 300 mg/kg/day), and aged with combined NMN and exercise (AENMN). Interventions lasted six weeks. Assessments included grip strength, muscle endurance, aerobic capacity, oral glucose tolerance test (OGTT), and indirect calorimetry, followed by biochemical and molecular analyses of NAMPT and SirT1 expression. Results: The AENMN group demonstrated significant improvements in maximal strength and aerobic endurance compared with the AS group (p < 0.05). Both NMN and exercise interventions increased blood NAMPT concentrations, with the highest levels observed in the AENMN group (p < 0.05). SirT1 expression was elevated in the ASNMN and AENMN groups relative to YS (p < 0.05). Glucose tolerance improved in the ASNMN and AENMN groups (p < 0.05). Enhanced energy metabolism in the AENMN group was indicated by increased oxygen consumption, elevated energy expenditure, and reduced respiratory quotient. Conclusions: NMN supplementation, particularly when combined with aerobic exercise, effectively improved aerobic performance, glucose regulation, and systemic energy metabolism in aged mice. These findings suggest that NMN, in synergy with exercise, may serve as a promising nutritional strategy to counteract age-associated metabolic and functional decline. Full article

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by amyloid-β (Aβ) accumulation, synaptic dysfunction, and cognitive decline. Current pharmacological treatments provide only symptomatic relief without altering disease progression. Photobiomodulation therapy (PBMT), a light-based intervention, has shown neuroprotective potential, although its exact neurobiological mechanisms in AD pathogenesis remain obscure. In this study, we investigated the effects of PBMT using a 660 nm wavelength light-emitting diode (LED) in 5xFAD transgenic mouse, a well-established model of early-onset AD. Mice were subjected to once daily PBMT sessions over a defined treatment period and outcomes were assessed through immunohistochemical analysis of hippocampal regions (CA1, CA2, CA3, and dentate gyrus) alongside behavioral testing using the Y-maze spontaneous alternation task. PBMT significantly reduced Aβ plaque load across hippocampal regions, accompanied by improved preservation of neuronal morphology. Furthermore, PBMT significantly upregulated SIRT1 expression, a critical regulator of synaptic plasticity and memory processes. Behaviorally, PBMT-treated mice displayed enhanced spatial working memory compared with controls, indicating a functional benefit linked to the observed molecular and structural changes. These findings suggest that 660 nm PBMT attenuates hallmark AD pathology, promotes neuroprotective pathways, and improves cognition, highlighting its potential as a disease-modifying therapy that warrants further preclinical and clinical investigation. Full article

Aging results from the combined effects of oxidative stress, chronic low-grade inflammation, mitochondrial decline, and cellular senescence, which together drive age-related disorders. Natural products ranging from polyphenols and terpenoids to alkaloids, polysaccharides, peptides, and marine metabolites can influence central pathways such as Nrf2/ARE, NF-κB, MAPK, JAK/STAT, AMPK/PGC1-α, mTOR, and SIRT1/FOXO. By doing so, they strengthen antioxidant defenses, temper inflammation, preserve mitochondrial balance, and regulate autophagy. Increasing attention is also being given to synergy, where combinations of bioactives can achieve stronger and more balanced effects than single agents alone. Advances in artificial intelligence are accelerating this discovery process, while greener extraction and smarter delivery systems such as deep eutectic solvents and nanostructured carriers are improving bioavailability and consistency. Together, these developments underscore the promise of natural product-based strategies for healthy aging. Grounded in rigor and reproducibility, this Special Issue aims to inspire translational advances toward healthier and more graceful aging. Full article

Under intensive farming systems and the global ban on antibiotic growth promoters (AGPs), early-weaned piglets exhibit incomplete physiological development, increasing their susceptibility to stress-related liver dysfunction and growth performance impairments. This study first investigated the effects of dietary supplementation with 0.2% tributyrin on the growth performance of 21-day-old weaned piglets over a 28-day period. Subsequently, on the final day, we examined its influence on antioxidant capacity, immune responses, and liver macrophage polarization using a 2 × 2 factorial challenge model, with the factors being diet (basal or tributyrin-supplemented) and immunological challenge (saline or lipopolysaccharide). The experimental results indicated that tributyrin had a significant enhancement on the average daily gain (ADG) of weaned piglets within the 0–14-day period (p < 0.05). Under lipopolysaccharide (LPS) challenge, tributyrin significantly increased the levels of catalase (CAT) and interleukin-10 (IL-10) while reducing the levels of malondialdehyde (MDA) and interleukin-6 (IL-6) in both serum and liver. Additionally, it significantly increased glutathione peroxidase (GSH-pX) activity in the serum and reduced glutathione (GSH) levels in the liver, and also decreased the serum level of interleukin-1β (IL-1β). Tributyrin downregulated pro-inflammatory cytokine gene expression while upregulating anti-inflammatory cytokine expression (p < 0.05). Furthermore, tributyrin significantly inhibited the expression of M1 macrophage polarization markers while enhancing those of M2 polarization (p < 0.05). Additionally, tributyrin suppressed SIRT1/NF-κB signaling pathway activation and promoted JAK2/STAT6 signaling pathway activation (p < 0.05). These findings exhibit that tributyrin alters the polarization of liver macrophages by regulating the SIRT1/NF-κB and JAK2/STAT6 signaling pathways, enhances antioxidant and immune functions, reduces LPS-induced liver inflammatory damage, and improves the growth performance of weaned piglets. Full article

The cryopreservation of Chengde polled goat semen plays a critical role in conserving genetic resources, enhancing the utilization efficiency of superior breeding bucks, and advancing artificial insemination techniques. However, spermatozoa are vulnerable to oxidative stress during the freezing process, which can significantly compromise sperm motility. In this study, pooled ejaculates from multiple bucks were divided into six groups, including a control group cryopreserved with conventional extender and five treatment groups supplemented with sericin at concentrations of 0.2%, 0.4%, 0.6%, 0.8%, and 1.0% (w/v). The results demonstrated that supplementation of the semen cryoprotectant with 0.6% sericin significantly improved post-thaw sperm viability to 65.25% in Chengde hornless goats, while concurrently reducing both the sperm abnormality rate (p < 0.05) and intracellular ROS levels (p < 0.05). Integrated TMT proteomics and LC/MS metabolomics further compared the 0.6% sericin group with the frozen control group and identified 162 differentially expressed proteins and 109 differential metabolites between the sericin supplementation and frozen control groups. Functional analysis revealed the significant enrichment of differential metabolites, such as glutamine, in the alanine, aspartate, and glutamate metabolism pathway, concomitant with the marked upregulation of antioxidant proteins including LRP8, GSTM3, and SIRT2. Thus, 0.6% sericin enhances cryotolerance primarily by improving sperm viability, reducing oxidative damage, and sustaining energy metabolism. These findings indicate that sericin enhances cryotolerance by reducing oxidative damage and supporting metabolic function, providing preliminary molecular insights for improving goat semen cryopreservation. Full article

Effective intervention on oxidative damage of bovine mammary epithelial cells (bMECs) is particularly important for reducing the incidence rate of mastitis. As a natural antioxidant, resveratrol (RES) can scavenge ROS, protecting cells from oxidative damage. However, the role of RES in bMECs and its potential protective mechanism have not been fully elucidated. Our results indicated that RES alleviated oxidative damage and enhanced antioxidant capacity in bMECs. Furthermore, RES increased SIRT5 expression and interacted with SIRT5, which attenuated cellular oxidative stress, inflammatory response and autophagy activity. Interestingly, SIRT5 and RES further improved mitochondrial dysfunction by increasing intracellular NADPH and GSH levels. Meanwhile, RES activated SIRT5 to regulate enzymatic activity of SDH and IDH2, which were important enzymes for producing intracellular ATP and antioxidants. RES specifically activated SIRT5 to attenuate the succinylation levels of intracellular IDH2 associated with interacting with SIRT5. Collectively, these outcomes revealed that RES might function as an activator of SIRT5 to attenuate oxidative damage of bMECs via activating SIRT5-IDH2 axis, resulting in increased GSH and NADPH production. Therefore, RES may be useful to prevent and control bovine mastitis by relieving oxidative damage. Full article

SIRT1-SREBP−1c/PGC−1α signaling is involved in the production of non-esterified fatty acids (NEFAs) and liver lipid metabolism disorders in ketotic calf. The molecules contained in extracellular vesicles (EVs) regulate intercellular communication, and research on calf hepatocytes−derived EVs has become a hot spot. We hypothesized that EVs in cell culture supernatants could affect lipid metabolism in hepatocyte models via SIRT1/SREBP−1c/PGC−1α signaling. Non-ketosis (NK, 0 mM NEFA) and clinical ketosis calf models (CK, 2.4 mM NEFAs) were established in vitro cultured calf hepatocytes and EVs were extracted from their supernatants as NK−derived EVs and CK−derived EVs, respectively. In vitro hepatocyte models, comprising a normal culture group (normal) and the group treated with NEFAs at 2.4 mM (2.4 NEFA), were treated with NK and CK−derived EVs. In addition, we transfected an SIRT1−overexpressing adenovirus into calf hepatocytes and determined the expression of key genes, enzymes, and proteins involved in the SIRT1/SREBP−1c/PGC−1α pathway. The results showed that the NK−derived EVs inhibited the expression of the SREBP−1c gene and protein and increased the expression of the SIRT1 and PGC−1α genes and proteins (p < 0.05). In contrast, CK−derived EVs induced lipid metabolism disorders in the normal hepatocyte group and aggravated NEFA-induced lipid metabolism imbalances in hepatocytes (p < 0.05). Moreover, overexpression of SIRT1 confirmed that EVs exert vital functions in hepatocyte lipid metabolism via SIRT1/SREBP−1c/PGC−1α signaling to regulate hepatocyte lipid metabolism. In summary, NK−derived EVs alleviated liver lipid metabolism disorders caused by NEFAs via modulation of SIRT1/SREBP−1c/PGC−1α signaling, while CK−derived EVs had the opposite effect. NK−derived EVs upregulated lipid oxidation-related genes and downregulated lipid synthesis-related genes, suggesting that NK−derived EVs could be used as biological extracts to alleviate lipid metabolism disorders in ketotic calf. Full article

Given the central role of neurogenesis in building a functional nervous system, we recently developed a zebrafish-based drug-screening protocol to uncover molecules and signalling pathways regulating spinal cord neurogenesis. In this study, we have expanded this drug screen and discovered a previously unknown role of deacetylase sirtuin 2 (SIRT2) in promoting the generation of serotonergic interneurons in the spinal cord. Treatments with specific SIRT2 inhibitors reduced the generation of serotonergic neurons in the spinal cord, which led to locomotor deficits. Our data suggest that SIRT2 regulates mitotic activity in progenitor cells to promote the generation of serotonergic neurons in developing animals. Together, our results uncover SIRT2 as a key regulator of spinal cord neurogenesis and position it as a promising target for strategies aimed at neural repair in spinal cord disorders. Full article

Cellular senescence plays a critical role in tumorigenesis and is recognized as a hallmark of colorectal cancer (CRC). Emerging evidence suggests that 5-fluorouracil (5-FU)-induced senescence may contribute to chemoresistance and tumor recurrence. Here, we investigated the effect of 5-FU on colon cancer cell senescence and whether MM-129 (pyrazolo[4,3-e]tetrazolo[4,5-b][1,2,4]triazine sulfonamide) can antagonize this activity. Senescence was identified by the expression of senescence-associated β-galactosidase (SA-β-gal) and cyclin-dependent kinase inhibitor 1A (p21) using qPCR, microscopy, flow cytometry, and immunohistochemistry. We also measured interleukin 6 (IL-6) and tumor necrosis factor (TNF-α) as key SASP cytokines, along with E-cadherin (CDH1), a marker of epithelial integrity. The SIRT1/STAT3 pathway was evaluated to elucidate the mechanism of MM-129′s action. MM-129 counteracted 5-FU-induced senescence in colon cancer models, reducing p21 levels in zebrafish xenografts and the number of SA-β-gal-positive cells in vitro and in tumor tissues from DLD-1 and HT-29 mouse xenografts. MM-129 also inhibited senescence-associated responses by suppressing SASP cytokines (IL-6, TNF-α) and restoring E-cadherin (CDH1), and it modulated the SIRT1/STAT3 axis, which may underlie the observed senotherapeutic effects. In conclusion, MM-129 represents a novel senotherapeutic candidate. By modulating the SIRT1/STAT3 axis, it may suppress the SASP and weaken pro-survival signaling, thereby facilitating selective clearance of senescent cells. Integrating senotherapeutics with conventional cancer therapies may enhance efficacy and open new avenues for translational research. Full article

Community-acquired pneumonia (CAP) is a leading cause of death, with mortality linked to an unbalanced host response. Sirtuin (Sirt)1, a histone deacetylase, regulating metabolism and epigenetics, may be fundamental in activating the innate immune response. Sirt1 mRNA expression was significantly reduced in monocytes from CAP patients (n = 76) upon admission compared to healthy controls (n = 42), with levels returning to normal after 30 days. Pharmacological activation of Sirt1 with SRT1720 decreased LPS- and K. pneumoniae-induced IL-6 release in primary human monocytes and decreased NF-κB activation in THP1 cells. In a mouse K. pneumoniae pneumosepsis model, SRT1720 strongly reduced neutrophil influx and degranulation markers in bronchoalveolar lavage fluid, lowered pulmonary concentrations of IL-6 and TNF-α, and reduced lung pathology scores. Simultaneously, it reduced neutrophil content in liver tissue and plasma transaminase levels, alongside a trend toward reduced liver necrosis. Plasma IL-6 and TNF-α were significantly lower in SRT1720-treated mice at 42 h. Finally, while SRT1720 did not impact bacterial loads in the lungs, it reduced bacterial burden in blood, with a similar trend observed in liver homogenates. In conclusion, the Sirt1 activator SRT1720 exerts anti-inflammatory effects on human monocytes, reduces local and systemic inflammation and organ injury, and diminishes bacterial dissemination in murine pneumosepsis. Full article

Anxiety disorders are closely associated with oxidative stress-mediated neuronal damage, mitochondrial dysfunction, and apoptosis. In this study, we investigated the neuroprotective effects of Lactiplantibacillus plantarum HY7715 in a mouse model of restraint stress-induced anxiety, and in neuronal cell models (HT-22 mouse hippocampal neuroblast cell and SH-SY5Y human neuroblastoma cells). Oral administration of HY7715 (1 × 10⁹ CFU/kg/day) alleviated anxiety-like behaviors significantly, as shown by increased central exploration in the open field test and prolonged open-arm activity in the elevated plus maze. HY7715 reduced serum norepinephrine levels elevated by stress, and restored hippocampal expression of brain-derived neurotrophic factor, while suppressing pro-inflammatory (NF-κB, IL-6) and pro-apoptotic (BAX, caspase-3) markers. It also increased expression of mitochondrial regulatory genes (SIRT1, mTOR), and decreased that of cytochrome c, in brain tissue. Histological analysis revealed that HY7715 preserved neuronal integrity in the CA1 and CA3 hippocampal regions. In vitro, HY7715 attenuated oxidative stress-induced cytotoxicity, decreased intracellular ROS accumulation, maintained mitochondrial activity, and inhibited apoptosis of both neuronal cell types, showing greater efficacy than the strain type L. plantarum KCTC3108. These findings suggest that HY7715 exerts neuroprotective effects by modulating oxidative stress/apoptosis/mitochondrial pathways, and highlight its potential as a psychobiotic for stress-related neuropsychiatric disorders. Full article

Sirtuin 5 is an NAD⁺-dependent lysine deacylase that is involved in various biological processes and has emerged as a promising target for pharmaceutical therapies. The development of highly potent and subtype-selective sirtuin 5 inhibitors for their application as chemical tools and drug candidates still poses a significant challenge. Based on our own optimized balsalazide-derived sirtuin 5 inhibitors, this work presents a systematic investigation of the inhibitory effects of derivatives with moieties that were guided by docking experiments to target the nicotinamide ribose vicinal hydroxy groups of the essential co-factor NAD⁺ via reversible covalent binding to potentially enhance their potency. Our results show that functionalizations with these moieties were tolerated to some extent and possessed a distinct stereo-selective preference. The (S)-configured cyanomethyl derivative 50 with an IC₅₀ of 27 µM emerged from our synthesized library of compounds as the most potent functionalized inhibitor and lies in a similar potency range to other established sirtuin 5 inhibitors. Our findings offer a deeper insight into the structure–activity relationships of our balsalazide-derived heterotriaryl-based sirtuin 5 inhibitors and thus could provide an avenue for further optimizations in the future. Full article

Endometriosis affects about 10% of reproductive-aged women, characterized by endometrial-like tissue outside the uterus, leading to chronic inflammation. The exact cause remains unknown, though genetic and epigenetic factors are increasingly recognized alongside traditional theories. The disease manifests in forms such as endometriomas, whether superficial or peritoneal, and deep infiltrating lesions, often causing chronic pain and infertility. Infertility affects nearly 50% of patients, requiring expensive treatments like in vitro fertilization. Oxidative stress plays a key role in endometriosis, with sirtuins, especially SIRT3, emerging as important regulators. SIRT3, located in mitochondria, helps manage oxidative stress and redox balance. Despite extensive research, no diagnostic biomarkers exist. This longitudinal study compares oxidative stress markers and SIRT3 levels in patients with different endometriosis types. While classic oxidative stress markers showed no significant differences, higher SIRT3 levels were observed in peripheral blood mononuclear cells of patients with deep endometriosis. Additionally, patients with prior surgeries had elevated SIRT3 levels, indicating a possible link between disease severity and SIRT3 expression. The findings suggest SIRT3 as a potential therapeutic target in endometriosis management. Full article