Mechanisms of Aging and the Preventive Effects of Resveratrol on Age-Related Diseases

Increased Prolylcarboxypeptidase Expression Can Serve as a Biomarker of Senescence in Culture

Prolylcarboxypeptidase (PRCP, PCP, Lysosomal Pro-X-carboxypeptidase, Angiotensinase C) controls angiotensin- and kinin-induced cell signaling. Elevation of PRCP appears to be activated in chronic inflammatory diseases [cardiovascular disease (CVD), diabetes] in proportion to severity. Vascular endothelial cell senescence and mitochondrial dysfunction have consistently been shown in models of CVD in aging. Cellular senescence, a driver of age-related dysfunction, can differentially alter the expression of lysosomal enzymes due to lysosomal membrane permeability. There is a lack of data demonstrating the effect of age-related dysfunction on the expression and function of PRCP. To explore the changes in PRCP, the PRCP-dependent prekallikrein (PK) pathway was characterized in early- and late-passage human pulmonary artery endothelial cells (HPAECs). Detailed kinetic analysis of cells treated with high molecular weight kininogen (HK), a precursor of bradykinin (BK), and PK revealed a mechanism by which senescent HPAECs activate the generation of kallikrein upon the assembly of the HK-PK complex on HPAECs in parallel with an upregulation of PRCP and endothelial nitric oxide (NO) synthase (eNOS) and NO formation. The NO production and expression of both PRCP and eNOS increased in early-passage HPAECs and decreased in late-passage HPAECs. Low activity of PRCP in late-passage HPAECs was associated with rapid decreased telomerase reverse transcriptase mRNA levels. We also found that, with an increase in the passage number of HPAECs, reduced PRCP altered the respiration rate. These results indicated that aging dysregulates PRCP protein expression, and further studies will shed light into the complexity of the PRCP-dependent signaling pathway in aging.

Therapeutic effects of resveratrol on epigenetic mechanisms in age-related diseases: A comprehensive review

Recently, various studies have shown that epigenetic changes are associated with aging and age-related diseases. Both animal and human models have revealed that epigenetic processes are involved in aging mechanisms. These processes happen at multiple levels and include histone modification, DNA methylation, and changes in noncoding RNA expression. Consequently, changes in the organization of chromatin and DNA accessibility lead to the regulation of gene expression. With increasing awareness of the pivotal function of epigenetics in the aging process, researchers' attention has been drawn to how these epigenetic changes can be modified to prevent, stop, or reverse aging, senescence, and age-related diseases. Among various agents that can affect epigenetic, polyphenols are well-known phytochemicals found in fruits, vegetables, and plants. Polyphenols are found to modify epigenetic-related mechanisms in various diseases and conditions, such as metabolic disorders, obesity, neurodegenerative diseases, cancer, and cardiovascular diseases. Resveratrol (RSV) is a member of the stilbene subgroup of polyphenols which is derived from various plants, such as grapes, apples, and blueberries. Therefore, herein, we aim to summarize how RSV affects different epigenetic processes to change aging-related mechanisms. Furthermore, we discuss its roles in age-related diseases, such as Alzheimer's, Parkinson's, osteoporosis, and cardiovascular diseases.

Unlocking the Therapeutic Potential of a Manila Clam-Derived Antioxidant Peptide: Insights into Mechanisms of Action and Cytoprotective Effects against Oxidative Stress

Reactive oxygen species (ROS) are implicated in various pathological conditions due to their ability to induce oxidative damage to cellular components. In this study, we investigated the antioxidant properties of a peptide isolated from the hydrolysate of Manila clam (Ruditapes philippinarum) muscle. Purification steps yielded RPTE2-2-4, exhibiting potent scavenging activities against DPPH•, HO•, and O2•-, akin to Vitamin C. Structural analysis showed that the isolated peptide, LFKKNLLTL, exhibited characteristics associated with antioxidant activity, including a short peptide length and the presence of aromatic and hydrophobic amino acid residues. Moreover, our study demonstrated the cytoprotective effects of the peptide against H2O2-induced oxidative stress in HepG2 cells. Pretreatment with the peptide resulted in a dose-dependent reduction in intracellular ROS levels and elevation of glutathione (GSH) levels, indicating its ability to modulate cellular defense mechanisms against oxidative damage. Furthermore, the peptide stimulated the expression of the cytoprotective enzyme heme oxygenase-1 (HO-1), further reinforcing its antioxidant properties. Overall, our findings highlight the potential of the Manila clam-derived peptide as a natural antioxidant agent with therapeutic implications for oxidative stress-related diseases. Further investigation into its mechanisms of action and in vivo efficacy is warranted to validate its therapeutic potential.

Resveratrol activates autophagy and protects from UVA-induced photoaging in human skin fibroblasts and the skin of male mice by regulating the AMPK pathway

Skin photoaging is mostly caused by ultraviolet A (UVA), although active medications to effectively counteract UVA-induced photoaging have not yet been created. Resveratrol, a naturally occurring polyphenol found in the skin of grapes, has been shown to have various biological functions such as anti-inflammatory and antioxidant characteristics. However, the role of resveratrol in UVA-induced photoaging has not been clarified. We investigated the mechanism of action of resveratrol by UVA irradiation of human skin fibroblasts (HSF) and innovatively modified a mouse model of photoaging. The results demonstrated that resveratrol promoted AMP-activated protein kinase (AMPK) phosphorylation to activate autophagy, reduce reactive oxygen species (ROS) production, inhibit apoptosis, and restore normal cell cycle to alleviate UVA-induced photoaging. In addition, subcutaneous injection of resveratrol not only improved the symptoms of roughness, erythema, and increased wrinkles in the skin of UVA photodamaged mice, but also alleviated epidermal hyperkeratosis and hyperpigmentation, reduced inflammatory responses, and inhibited collagen fiber degradation. In conclusion, our studies proved that resveratrol can treat UVA-induced photoaging and elucidated the possible molecular mechanisms involved, providing a new therapeutic strategy for future anti-aging.

Kaempferol: Paving the path for advanced treatments in aging-related diseases

Aging-related diseases (ARDs) are a major global health concern, and the development of effective therapies is urgently needed. Kaempferol, a flavonoid found in several plants, has emerged as a promising candidate for ameliorating ARDs. This comprehensive review examines Kaempferol's chemical properties, safety profile, and pharmacokinetics, and highlights its potential therapeutic utility against ARDs. Kaempferol's therapeutic potential is underpinned by its distinctive chemical structure, which confers antioxidative and anti-inflammatory properties. Kaempferol counteracts reactive oxygen species (ROS) and modulates crucial cellular pathways, thereby combating oxidative stress and inflammation, hallmarks of ARDs. Kaempferol's low toxicity and wide safety margins, as demonstrated by preclinical and clinical studies, further substantiate its therapeutic potential. Compelling evidence supports Kaempferol's substantial potential in addressing ARDs through several mechanisms, notably anti-inflammatory, antioxidant, and anti-apoptotic actions. Kaempferol exhibits a versatile neuroprotective effect by modulating various proinflammatory signaling pathways, including NF-kB, p38MAPK, AKT, and the β-catenin cascade. Additionally, it hinders the formation and aggregation of beta-amyloid protein and regulates brain-derived neurotrophic factors. In terms of its anticancer potential, kaempferol acts through diverse pathways, inducing apoptosis, arresting the cell cycle at the G2/M phase, suppressing epithelial-mesenchymal transition (EMT)-related markers, and affecting the phosphoinositide 3-kinase/protein kinase B signaling pathways. Subsequent studies should focus on refining dosage regimens, exploring innovative delivery systems, and conducting comprehensive clinical trials to translate these findings into effective therapeutic applications.

Resveratrol and vascular health: evidence from clinical studies and mechanisms of actions related to its metabolites produced by gut microbiota

Cardiovascular diseases are among the leading causes of mortality worldwide, with dietary factors being the main risk contributors. Diets rich in bioactive compounds, such as (poly)phenols, have been shown to potentially exert positive effects on vascular health. Among them, resveratrol has gained particular attention due to its potential antioxidant and anti-inflammatory action. Nevertheless, the results in humans are conflicting possibly due to interindividual different responses. The gut microbiota, a complex microbial community that inhabits the gastrointestinal tract, has been called out as potentially responsible for modulating the biological activities of phenolic metabolites in humans. The present review aims to summarize the main findings from clinical trials on the effects of resveratrol interventions on endothelial and vascular outcomes and review potential mechanisms interesting the role of gut microbiota on the metabolism of this molecule and its cardioprotective metabolites. The findings from randomized controlled trials show contrasting results on the effects of resveratrol supplementation and vascular biomarkers without dose-dependent effect. In particular, studies in which resveratrol was integrated using food sources, i.e., red wine, reported significant effects although the resveratrol content was, on average, much lower compared to tablet supplementation, while other studies with often extreme resveratrol supplementation resulted in null findings. The results from experimental studies suggest that resveratrol exerts cardioprotective effects through the modulation of various antioxidant, anti-inflammatory, and anti-hypertensive pathways, and microbiota composition. Recent studies on resveratrol-derived metabolites, such as piceatannol, have demonstrated its effects on biomarkers of vascular health. Moreover, resveratrol itself has been shown to improve the gut microbiota composition toward an anti-inflammatory profile. Considering the contrasting findings from clinical studies, future research exploring the bidirectional link between resveratrol metabolism and gut microbiota as well as the mediating effect of gut microbiota in resveratrol effect on cardiovascular health is warranted.

Unveiling the potential effects of resveratrol in lung cancer treatment: Mechanisms and nanoparticle-based drug delivery strategies

Lung cancer ranks among the most prevalent forms of cancer and remains a significant factor in cancer-related mortality across the world. It poses significant challenges to healthcare systems and society as a whole due to its high incidence, mortality rates, and late-stage diagnosis. Resveratrol (RV), a natural compound found in various plants, has shown potential as a nanomedicine for lung cancer treatment. RV has varied effects on cancer cells, including promoting apoptosis by increasing pro-apoptotic proteins (Bax and Bak) and decreasing anti-apoptotic proteins (Bcl-2). It also hinders cell proliferation by influencing important signaling pathways (MAPK, mTOR, PI3K/Akt, and Wnt/β-catenin) that govern cancer progression. In addition, RV acts as a potent antioxidant, diminishing oxidative stress and safeguarding cells against DNA damage. However, using RV alone in cancer treatment has drawbacks, such as low bioavailability, lack of targeting ability, and susceptibility to degradation. In contrast, nanoparticle-based delivery systems address these limitations and hold promise for improving treatment outcomes in lung cancer; nanoparticle formulations of RV offer advantages such as improved drug delivery, increased stability, controlled release, and targeted delivery to lung cancer cells. This article will provide an overview of lung cancer, explore the potential of RV as a therapeutic agent, discuss the benefits and challenges of nanoparticle-based drug delivery, and highlight the promise of RV nanoparticles for cancer treatment, including lung cancer. By optimizing these systems for clinical application, future studies aim to enhance overall treatment outcomes and improve the prognosis for lung cancer patients.

Anti-aging Strategies and Topical Delivery of Biopolymer-based Nanocarriers for Skin Cancer Treatment

Environmental factors like UV radiation and epigenetic changes are significant factors for skin cancer that trigger early aging. This review provides essential information on cancer development concerning aging, the receptors involved, and the therapeutic targets. Biopolymers like polysaccharide, polyphenols, proteins, and nucleic acid plays a vital role in the regulation of normal cell homeostasis. Therefore, it is pertinent to explore the role of biopolymers as antiaging formulations and the possibility of these formulations being used against cancer via topical administrations. As UV radiation is one of the predominant factors in causing skin cancer, the association of receptors between aging and cancer indicated that insulin receptor, melatonin receptor, toll-like receptor, SIRT 1 receptor, tumor-specific T cell receptor and mitochondria-based targeting could be used to direct therapeutics for suppression of cancer and prevent aging. Biopolymer-based nanoformulations have tremendously progressed by entrapment of drugs like curcumin and resveratrol which can prevent cancer and aging simultaneously. Certain protein signaling or calcium and ROS signaling pathways are different for cancer and aging. The involvement of mitochondrial DNA mutation along with telomere shortening with a change in cellular energetics leading to genomic instability in the aging process can also induce mitochondrial dysfunction and epigenetic alterations leading to skin cancer. Therefore, the use of biopolymers as a topical supplement during the aging process can result in the prevention of cancer.

Regulation of the Notch signaling pathway by natural products for cancer therapy

The Notch signaling pathway is an evolutionarily conserved pathway that modulates normal biological processes involved in cellular differentiation, apoptosis, and stem cell self-renewal in a context-dependent fashion. Attributed to its pleiotropic physiological roles, both overexpression and silencing of the pathway are associated with the emergence, progression, and poorer prognosis in various types of cancer. To decrease disease incidence and promote survival, targeting Notch may have chemopreventive and anti-cancer effects. Natural products with profound historical origins have distinguished themselves from other therapies due to their easy access, high biological compatibility, low toxicity, and reliable effects at specific physiological sites in vivo. This review describes the Notch signaling pathway, particularly its normal activation process, and some main illnesses related to Notch signaling pathway dysregulation. Emphasis is placed on the effects and mechanisms of natural products targeting the Notch signaling pathway in diverse cancer types, including curcumin, ellagic acid (EA), resveratrol, genistein, epigallocatechin-3-gallate (EGCG), quercetin, and xanthohumol and so on. Existing evidence indicates that natural products are feasible solution to fight against cancer by targeting Notch signaling, either alone or in combination with current therapeutic agents.

Gut microbiota defined epigenomes of Alzheimer's and Parkinson's diseases reveal novel targets for therapy

The origins of Alzheimer's disease (AD) and Parkinson's disease (PD) involve genetic mutations, epigenetic changes, neurotoxin exposure and gut microbiota dysregulation. The gut microbiota's dynamic composition and its metabolites influence intestinal and blood-brain barrier integrity, contributing to AD and PD development. This review explores protein misfolding, aggregation and epigenetic links in AD and PD pathogenesis. It also highlights the role of a leaky gut and the microbiota-gut-brain axis in promoting these diseases through inflammation-induced epigenetic alterations. In addition, we investigate the potential of diet, probiotics and microbiota transplantation for preventing and treating AD and PD via epigenetic modifications, along with a discussion related to current challenges and future considerations. These approaches offer promise for translating research findings into practical clinical applications.

Gut microbiota: an ideal biomarker and intervention strategy for aging

Population aging is a substantial challenge for the global sanitation framework. Unhealthy aging tends to be accompanied by chronic diseases such as cardiovascular disease, diabetes, and cancer, which undermine the welfare of the elderly. Based on the fact that aging is inevitable but retarding aging is attainable, flexible aging characterization and efficient anti-aging become imperative for healthy aging. The gut microbiome, as the most dynamic component interacting with the organism, can affect the aging process through its own structure and metabolites, thus holding the potential to become both an ideal aging-related biomarker and an intervention strategy. This review summarizes the value of applying gut microbiota as aging-related microbial biomarkers in diagnosing aging state and monitoring the effect of anti-aging interventions, ultimately pointing to the future prospects of microbial intervention strategies in maintaining healthy aging.

Cells in Atherosclerosis: Focus on Cellular Senescence from Basic Science to Clinical Practice

Aging is a major risk factor of atherosclerosis through different complex pathways including replicative cellular senescence and age-related clonal hematopoiesis. In addition to aging, extracellular stress factors, such as mechanical and oxidative stress, can induce cellular senescence, defined as premature cellular senescence. Senescent cells can accumulate within atherosclerotic plaques over time and contribute to plaque instability. This review summarizes the role of cellular senescence in the complex pathophysiology of atherosclerosis and highlights the most important senotherapeutics tested in cardiovascular studies targeting senescence. Continued bench-to-bedside research in cellular senescence might allow the future implementation of new effective anti-atherosclerotic preventive and treatment strategies in clinical practice.

Doxorubicin-Induced Cardiac Senescence Is Alleviated Following Treatment with Combined Polyphenols and Micronutrients through Enhancement in Mitophagy

Oxidative stress and impaired mitophagy are the hallmarks of cardiomyocyte senescence. Specifically, a decrease in mitophagic flux leads to the accumulation of damaged mitochondria and the development of senescence through increased ROS and other mediators. In this study, we describe the preventive role of A5+, a mix of polyphenols and other micronutrients, in doxorubicin (DOXO)-induced senescence of H9C2 cells. Specifically, H9C2 cells exposed to DOXO showed an increase in the protein expression proteins of senescence-associated genes, p21 and p16, and a decrease in the telomere binding factors TRF1 and TRF2, indicative of senescence induction. Nevertheless, A5+ pre-treatment attenuated the senescent-like cell phenotype, as evidenced by inhibition of all senescent markers and a decrease in SA-β-gal staining in DOXO-treated H9C2 cells. Importantly, A5+ restored the LC3 II/LC3 I ratio, Parkin and BNIP3 expression, therefore rescuing mitophagy, and decreased ROS production. Further, A5+ pre-treatment determined a ripolarization of the mitochondrial membrane and improved basal respiration. A5+-mediated protective effects might be related to its ability to activate mitochondrial SIRT3 in synergy with other micronutrients, but in contrast with SIRT4 activation. Accordingly, SIRT4 knockdown in H9C2 cells further increased MnSOD activity, enhanced mitophagy, and reduced ROS generation following A5+ pre-treatment and DOXO exposure compared to WT cells. Indeed, we demonstrated that A5+ protects H9C2 cells from DOXO-induced senescence, establishing a new specific role for A5+ in controlling mitochondrial quality control by restoring SIRT3 activity and mitophagy, which provided a molecular basis for the development of therapeutic strategies against cardiomyocyte senescence.

The Pharmacological Properties of Red Grape Polyphenol Resveratrol: Clinical Trials and Obstacles in Drug Development

Resveratrol is a stilbenoid from red grapes that possesses a strong antioxidant activity. Resveratrol has been shown to have anticancer activity, making it a promising drug for the treatment and prevention of numerous cancers. Several in vitro and in vivo investigations have validated resveratrol's anticancer capabilities, demonstrating its ability to block all steps of carcinogenesis (such as initiation, promotion, and progression). Additionally, resveratrol has been found to have auxiliary pharmacological effects such as anti-inflammatory, cardioprotective, and neuroprotective activity. Despite its pharmacological properties, several obstacles, such as resveratrol's poor solubility and bioavailability, as well as its adverse effects, continue to be key obstacles to drug development. This review critically evaluates the clinical trials to date and aims to develop a framework to develop resveratrol into a clinically viable drug.

Long-term detraining reverses the improvement of lifelong exercise on skeletal muscle ferroptosis and inflammation in aging rats: fiber-type dependence of the Keap1/Nrf2 pathway

We investigated the effects of lifelong aerobic exercise and 8 months of detraining after 10 months of aerobic training on circulation, skeletal muscle oxidative stress, and inflammation in aging rats. Sprague-Dawley rats were randomly assigned to the control (CON), detraining (DET), and lifelong aerobic training (LAT) groups. The DET and LAT groups began aerobic treadmill exercise at the age of 8 months and stopped training at the 18th and 26th month, respectively; all rats were sacrificed when aged 26 months. Compared with CON, LAT remarkably decreased serum and aged skeletal muscle 4-hydroxynonenal (4-HNE) and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels. Superoxide dismutase 2(SOD2) levels were higher in the LAT group than in the CON group in skeletal muscle. However, DET remarkably decreased SOD2 protein expression and content in the skeletal muscle and increased malondialdehyde (MDA) level compared with LAT. Compared with LAT, DET remarkably downregulated adiponectin and upregulated tumor necrosis factor alpha (TNF-α) expression, while phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), and 70-kDa ribosomal protein S6 kinase (P70S6K) protein expression decreased, and that of FoxO1 and muscle atrophy F-box (MAFbX) proteins increased in the quadriceps femoris. Adiponectin and TNF-α expression in the soleus muscle did not change between groups, whereas that of AKT, mammalian target of rapamycin (mTOR), and P70S6K was lower in the soleus in the DET group than in that in the LAT group. Compared with that in the LAT group, sestrin1 (SES1) and nuclear factor erythroid 2-related factor 2 (Nrf2) protein expression in the DET group was lower, whereas Keap1 mRNA expression was remarkably upregulated in the quadriceps femoris. Interestingly, the protein and mRNA levels of SES1, Nrf2, and Keap1 in soleus muscle did not differ between groups. LAT remarkably upregulated ferritin heavy polypeptide 1(FTH), glutathione peroxidase 4(GPX4), and solute carrier family 7member 11 (SLC7A11) protein expression in the quadriceps femoris and soleus muscles, compared with CON. However, compared with LAT, DET downregulated FTH, GPX4, and SLC7A11 protein expression in the quadriceps femoris and soleus muscles. Long-term detraining during the aging phase reverses the improvement effect of lifelong exercise on oxidative stress, inflammation, ferroptosis, and muscle atrophy in aging skeletal muscle. The quadriceps femoris is more evident than the soleus, which may be related to the different changes in the Keap1/Nrf2 pathway in different skeletal muscles.

NEUROMETABOLOMIC IMPACTS OF MODELED WILDFIRE SMOKE AND PROTECTIVE BENEFITS OF ANTI-AGING THERAPEUTICS IN AGED FEMALE C57BL/6J MICE

Wildland fires have become progressively more extensive over the past 30 years in the US, and now routinely generate smoke that deteriorates air quality for most of the country. We explored the neurometabolomic impact that smoke derived from biomass has on older (18 months) female C57BL/6J mice, both acutely and after 10 weeks of recovery from exposures. Mice (N=6/group) were exposed to wood smoke (WS) 4 hours/day, every other day, for 2 weeks (7 exposures total) to an average concentration of 0.448mg/m 3 per exposure. One group was euthanized 24 hours after the last exposure. Other groups were then placed on 1 of 4 treatment regimens for 10 weeks after wood smoke exposures: vehicle; resveratrol in chow plus nicotinamide mononucleotide in water (RNMN); senolytics via gavage (dasatanib+quercetin; DQ); or both RNMN with DQ (RNDQ). Among the findings, the aging from 18 months to 21 months was associated with the greatest metabolic shift, including changes in nicotinamide metabolism, with WS exposure effects that were relatively modest. WS caused a reduction in NAD+ within the prefrontal cortex immediately after exposure and a long-term reduction in serotonin that persisted for 10 weeks. The serotonin reductions were corroborated by forced swim tests, which revealed an increased immobility (reduction in motivation) immediately post-exposure and persisted for 10 weeks. RNMN had the most beneficial effects after WS exposure, while RNDQ caused markers of brain aging to be upregulated within WS-exposed mice. Findings highlight the persistent neurometabolomic and behavioral effects of woodsmoke exposure in an aged mouse model.

Significance Statement

Neurological impacts of wildfire smoke are largely underexplored but include neuroinflammation and metabolic changes. The present study highlights modulation of major metabolites in the prefrontal cortex and behavioral consequences in aged (18 month) female mice that persists 10 weeks after wood smoke exposure ended. Supplements derived from the anti-aging field were able to mitigate much of the woodsmoke effect, especially a combination of resveratrol and nicotinamide mononucleotide.

Resveratrol affects ccRCC cell senescence and macrophage polarization by regulating the stability of CCNB1 by RBM15

Aim: The present study sought to investigate the therapeutic effect of resveratrol on clear cell renal cell carcinoma. Materials & methods: Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine assays were used to verify the cell proliferation. Transwell, real-time quantitative transcription PCR, western blot and β-galactosidase staining were used to verify the migration, macrophage polarization and senescence. The tumor inhibitory effect of resveratrol on clear cell renal cell carcinoma was verified in vivo. Results: This study confirmed that resveratrol could affect the stability of CCNB1 mRNA mediated by RBM15 and inhibit the cancer process by inhibiting the expression of EP300/CBP from the perspective of cell senescence. Conclusion: Resveratrol is able to treat clear cell renal cell carcinoma through RBM15-induced cell senescence.

Vascular Ageing: Mechanisms, Risk Factors, and Treatment Strategies

Ageing constitutes the biggest risk factor for poor health and adversely affects the integrity and function of all the cells, tissues, and organs in the human body. Vascular ageing, characterised by vascular stiffness, endothelial dysfunction, increased oxidative stress, chronic low-grade inflammation, and early-stage atherosclerosis, may trigger or exacerbate the development of age-related vascular diseases, which each year contribute to more than 3.8 million deaths in Europe alone and necessitate a better understanding of the mechanisms involved. To this end, a large number of recent preclinical and clinical studies have focused on the exponential accumulation of senescent cells in the vascular system and paid particular attention to the specific roles of senescence-associated secretory phenotype, proteostasis dysfunction, age-mediated modulation of certain microRNA (miRNAs), and the contribution of other major vascular risk factors, notably diabetes, hypertension, or smoking, to vascular ageing in the elderly. The data generated paved the way for the development of various senotherapeutic interventions, ranging from the application of synthetic or natural senolytics and senomorphics to attempt to modify lifestyle, control diet, and restrict calorie intake. However, specific guidelines, considering the severity and characteristics of vascular ageing, need to be established before widespread use of these agents. This review briefly discusses the molecular and cellular mechanisms of vascular ageing and summarises the efficacy of widely studied senotherapeutics in the context of vascular ageing.

Potential therapeutic targets for age-related macular degeneration: The nuclear option

The functions and activities of nuclear receptors, the largest family of transcription factors in the human genome, have classically focused on their ability to act as steroid and hormone sensors in endocrine organs. However, they are responsible for a diverse array of physiological functions, including cellular homeostasis and metabolism, during development and aging. Though the eye is not a traditional endocrine organ, recent studies have revealed high expression levels of nuclear receptors in cells throughout the posterior pole. These findings have precipitated an interest in investigating the role of these transcription factors in the eye as a function of age and ocular disease, in particular age-related macular degeneration (AMD). As the leading cause of vision impairment in the elderly, identifying signaling pathways that may be targeted for AMD therapy is of great importance, given the lack of therapeutic options for over 85% of patients with this disease. Herein we review this relatively new field and recent findings supporting the hypothesis that the eye is a secondary endocrine organ, in which nuclear receptors serve as the bedrock for biological processes in cells vulnerable in AMD, including retinal pigment epithelial and choroidal endothelial cells, and discuss the therapeutic potential of targeting these receptors for AMD.

Mesenchymal Stem Cells for Treating Alzheimer's Disease: Cell Therapy and Chemical Reagent Pretreatment

As the size of the population aged 65 and older continues to grow, the incidence and mortality rates of Alzheimer's disease (AD) are increasing annually. Unfortunately, current treatments only treat symptoms temporarily and do not alter the patients' life expectancy or course of AD. Mesenchymal stem cells (MSCs) have shown a certain therapeutic potential in neurodegenerative diseases including AD due to their neuroinflammatory regulation and neuroprotective effects. However, the low survival and homing rates of MSCs after transplantation seriously affect their therapeutic effectiveness. Therefore, appropriate in vitro preconditioning is necessary to increase the survival and homing rates of MSCs to improve their effectiveness in treating AD. Here we summarize the therapeutic mechanisms of MSCs in AD and the chemical reagents used for the pretreatment of MSCs.

How can we modulate aging through nutrition and physical exercise? An epigenetic approach

The World Health Organization predicts that by 2050, 2.1 billion people worldwide will be over 60 years old, a drastic increase from only 1 billion in 2019. Considering these numbers, strategies to ensure an extended "healthspan" or healthy longevity are urgently needed. The present study approaches the promotion of healthspan from an epigenetic perspective. Epigenetic phenomena are modifiable in response to an individual's environmental exposures, and therefore link an individual's environment to their gene expression pattern. Epigenetic studies demonstrate that aging is associated with decondensation of the chromatin, leading to an altered heterochromatin structure, which promotes the accumulation of errors. In this review, we describe how aging impacts epigenetics and how nutrition and physical exercise can positively impact the aging process, from an epigenetic point of view. Canonical histones are replaced by histone variants, concomitant with an increase in histone post-translational modifications. A slight increase in DNA methylation at promoters has been observed, which represses transcription of previously active genes, in parallel with global genome hypomethylation. Aging is also associated with deregulation of gene expression - usually provided by non-coding RNAs - leading to both the repression of previously transcribed genes and to the transcription of previously repressed genes. Age-associated epigenetic events are less common in individuals with a healthy lifestyle, including balanced nutrition, caloric restriction and physical exercise. Healthy aging is associated with more tightly condensed chromatin, fewer PTMs and greater regulation by ncRNAs.

Resveratrol and Sir2 Reverse Sleep and Memory Defects Induced by Amyloid Precursor Protein

Resveratrol (RES), a natural polyphenolic phytochemical, has been suggested as a putative anti-aging molecule for the prevention and treatment of Alzheimer's disease (AD) by the activation of sirtuin 1 (Sirt1/Sir2). In this study, we tested the effects of RES and Sirt1/Sir2 on sleep and courtship memory in a Drosophila model by overexpression of amyloid precursor protein (APP), whose duplications and mutations cause familial AD. We found a mild but significant transcriptional increase of Drosophila Sir2 (dSir2) by RES supplementation for up to 17 days in APP flies, but not for 7 days. RES and dSir2 almost completely reversed the sleep and memory deficits in APP flies. We further demonstrated that dSir2 acts as a sleep promotor in Drosophila neurons. Interestingly, RES increased sleep in the absence of dSir2 in dSir2-null mutants, and RES further enhanced sleep when dSir2 was either overexpressed or knocked down in APP flies. Finally, we showed that Aβ aggregates in APP flies were reduced by RES and dSir2, probably via inhibiting Drosophila β-secretase (dBACE). Our data suggest that RES rescues the APP-induced behavioral deficits and Aβ burden largely, but not exclusively, via dSir2.

Characterization of Cell Death Induced by Imine Analogs of Trans-Resveratrol: Induction of Mitochondrial Dysfunction and Overproduction of Reactive Oxygen Species Leading to, or Not, Apoptosis without the Increase in the S-Phase of the Cell Cycle

Trans-resveratrol (RSV) is a non-flavonoid polyphenol (stilbene) with numerous biological activities, such as anti-tumor activities. However, RSV is rapidly metabolized, which limits its therapeutic use. The availability of RSV analogues with similar activities for use in vivo is therefore a major challenge. For this purpose, several isomeric analogues of RSV, aza-stilbenes (AZA-ST 1a–g), were synthesized, and their toxicities were characterized and compared to those of RSV on murine N2a neuronal cells using especially flow cytometric methods. All AZA-ST 1a–g have an inhibitory concentration 50 (IC50) between 11.3 and 25 µM when determined by the crystal violet assay, while that of RSV is 14.5 µM. This led to the characterization of AZA-ST 1a–g—induced cell death, compared to RSV, using three concentrations encompassing the IC50s (6.25, 12.5 and 25 µM). For AZA-ST 1a–g and RSV, an increase in plasma membrane permeability to propidium iodide was observed, and the proportion of cells with depolarized mitochondria measured with DiOC6(3) was increased. An overproduction of reactive oxygen species (ROS) was also observed on whole cells and at the mitochondrial level using dihydroethidium and MitoSox Red, respectively. However, only RSV induced a mode of cell death by apoptosis associated with a marked increase in the proportion of cells with condensed and/or fragmented nuclei (12.5 µM: 22 ± 9%; 25 µM: 80 ± 10%) identified after staining with Hoechst 33342 and which are characteristic of apoptotic cells. With AZA-ST, a slight but significant increase in the percentage of apoptotic cells was only detected with AZA-ST 1b (25 µM: 17 ± 1%) and AZA-ST 1d (25 µM: 26 ± 4%). Furthermore, only RSV induced significant cell cycle modifications associated with an increase in the percentage of cells in the S phase. Thus, AZA-ST 1a–g—induced cell death is characterized by an alteration of the plasma membrane, an induction of mitochondrial depolarization (loss of ΔΨm), and an overproduction of ROS, which may or may not result in a weak induction of apoptosis without modification of the distribution of the cells in the different phases of the cell cycle.

Biophysical and Biochemical Characterization of the Binding of the MarR-like Transcriptional Regulator Saro_0803 to the nov1 Promotor and Its Inhibition by Resveratrol

Saro_0803 is a transcriptional factor modulating the transcription of the stilbene-degrading enzyme gene nov1 in Novosphingobium aromaticivorans DSM 12444. Reportedly, Saro_0803 undergoes resveratrol-mediated dissociation from the nov1 promotor and distinguishes resveratrol from its precursors, p-coumaric acid and trans-cinnamic acid, enabling the transcriptional factor to serve as a biosensor component for regulating resveratrol biosynthesis. However, little is known about the molecular mechanisms underlying the Saro_0803 interactions with either the nov1 promotor gene or resveratrol, which undermines the potential for Saro_0803 to be further modified for improved biosynthetic performance and other applications. Here, we report the discovery of the 22 bp A/T-rich Saro_0803 binding site near the −10 box of the nov1 promotor (named nov1p22bp). As validated by molecular docking-guided mutagenesis and binding affinity assays, the Saro_0803 binding of its target DNA sequence relies on charge-predominating interactions between several typical positively charged residues and nucleic acid. Furthermore, we semi-quantified the influence of resveratrol presence on Saro_0803–nov1p22bp interaction and identified a bilateral hydrophobic pocket within Saro_0803 comprising four aromatic residues that are crucial to maintaining the resveratrol binding capability of the transcriptional factor. Our data are beneficial to understanding saro_0803′s structural and functional properties, and could provide theoretical clues for future adaptations of this transcriptional factor.

Ageing and chronic obstructive pulmonary disease: interrelationships

PURPOSE OF REVIEW

As life expectancy increases, the ageing population accrues an increasing burden of chronic conditions and functional compromise. Some conditions that lead to compromise are deemed part of 'natural ageing,' whereas others are considered to represent disease processes. Ageing ('a natural process') and chronic obstructive pulmonary disease ('a disease') share many common features, both pulmonary and systemic. At times, the pathways of injury are the same, and at times they are concurrent. In some cases, age and disease are separated not by the presence but by the severity of a finding or condition. This brief review aims to compare some of the similarities between ageing and COPD and to compare/contrast mechanisms for each.

RECENT FINDINGS

At the cellular level, the natural process of ageing includes multiple systemic and molecular mechanisms. COPD, though defined by progressive pulmonary compromise, can also be a systemic disease/process. It has become evident that specific senescence pathways like p-16 and the sirtuin family of proteins are implicated both in ageing and in COPD. Also common to both ageing and COPD are increased inflammatory markers, leucocyte response abnormalities, and DNA-level abnormalities.

SUMMARY

The prevalence of COPD increases with increasing age. COPD contributes to the accrued burden of chronic disease and is a significant contributor to morbidity and mortality in this population. This review attempts to summarize some of similarities between ageing and COPD and their underlying mechanisms.

Therapeutic opportunities for senolysis in cardiovascular disease

Cellular senescence within the cardiovascular system has, until recently, been understudied and unappreciated as a factor in the development of age-related cardiovascular diseases such as heart failure, myocardial infarction and atherosclerosis. This is in part due to challenges with defining senescence within post-mitotic cells such as cardiomyocytes. However, recent evidence has demonstrated senescent-like changes, including a senescence-associated secretory phenotype (SASP), in cardiomyocytes in response to ageing and cell stress. Other replicating cells, including fibroblasts and vascular smooth muscle cells, within the cardiovascular system have also been shown to undergo senescence and contribute to disease pathogenesis. These findings coupled with the emergence of senolytic therapies, to target and eliminate senescent cells, have provided fascinating new avenues for management of several age-related cardiovascular diseases with high prevalence. In this review, we discuss the role of senescent cells within the cardiovascular system and highlight the contribution of senescence cells to common cardiovascular diseases. We discuss the emerging role for senolytics in cardiovascular disease management while highlighting important aspects of senescence biology which must be clarified before the potential of senolytics can be fully realized.

Resveratrol improves diabetes-induced cognitive dysfunction in part through the miR-146a-5p/TXNIP axis

Resveratrol (RSV) has been shown to have a neuroprotective effect in various central nervous system disorders, although the role of RSV in diabetes-induced cognitive dysfunction is still not fully elucidated. Here, we investigated whether RSV improved diabetes-related cognitive dysfunction in vivo and in vitro. We induced a rat diabetic model with a high-fat and high-sucrose diet followed by intraperitoneal injection of streptozotocin and a diabetic neuron cell model by stimulation with high levels of glucose. We observed that RSV improved impairment in spatial learning and memory in the Morris water maze test (MWM) and novel object recognition test (ORT) in diabetic rats. RSV reversed the reduced miR-146a-5p and upregulated thioredoxin-interacting protein (TXNIP) and inhibited the diabetes-induced increase in interleukin (IL)-1β and tumor necrosis factor (TNF)-α levels in vivo and in vitro. RSV also inhibited diabetes-induced endoplasmic reticulum stress (ESR) by reducing ESR-related protein expression in vivo and in vitro. Moreover, inhibition of miR-146a-5p partially abolished the protective effects of RSV in HG-treated primary neurons. Additionally, we used starBase to predict that miR-146a-5p interacts with TXNIP, which we then verified using a luciferase reporter gene assay. We further observed that miR-146a-5p regulates the mRNA and protein expression of TXNIP in vitro, indicating that the miR-146a-5p/TXNIP axis is involved in the regulation of cognitive dysfunction in a rat diabetic model. Collectively, these results demonstrate that RSV plays a neuroprotective role in diabetes-associated cognitive dysfunction at least in part through regulation of the miR-146a-5p/TXNIP axis.

Combination therapy of cisplatin and resveratrol to induce cellular aging in gastric cancer cells: Focusing on oxidative stress, and cell cycle arrest

Background: As a medical dilemma, gastric cancer will have 7.3 million new cases in 2040. Despite the disease's high economic and global burden, conventional chemotherapy regimens containing cisplatin have insufficient effectiveness and act non-specifically, leading to several adverse drug reactions To address these issues, the biological efficacy of the cisplatin-resveratrol combination was tested. Methods: To find IC50, gastric adenocarcinoma cells (AGS) were exposed to different concentrations of resveratrol and cisplatin. Anti-cancer and anti-metastatic effects of 100 M resveratrol with concentrations of cisplatin (25, 50, and 100 g/ml) were studied by assessing ß-galactosidase and telomerase activities, senescence and migration gene expression, reactive oxygen species (ROS) level, and cell cycle arrest. Results: Co-administration of cisplatin and resveratrol increased ß-galactosidase activity, ROS level as a key marker of oxidative stress, p53, p38, p16, p21, and MMP-2 gene expression, and induced G0/G1 cell cycle arrest. Additionally, telomerase activity, pro-inflammatory gene expression, and cell invasion were suppressed. The best results were achieved with 100 g/ml cisplatin co-administered with resveratrol. Conclusion: The current study proved the synergistic effect of the cisplatin-resveratrol combination on suppressing metastasis and inducing apoptosis and cell senescence through targeting P38/P53 and P16/P21 pathways. Such promising results warrant translation to animal models and the clinic. This may lead to cost-effective, available, and accessible treatment regimens with targeted action and the fewest ADRs.

Targeting AMPK signaling by polyphenols: a novel strategy for tackling aging

Aging is an inevitable biological process and is accompanied by a gradual decline of physiological functions, such as the incidence of age-related diseases. Aging becomes a major burden and challenge for society to prevent or delay the occurrence and development of these age-related diseases. AMPK is a key regulator of intracellular energy and participates in the adaptation of calorie restriction. It is also an important mediator of nutritionally sensitive pathways that regulate the biological effects of nutrient active ingredients. AMPK can limit proliferation and activate autophagy. Recent studies have shown that nutritional intervention can delay aging and lessen age-related diseases in many animal and even human models. Polyphenols function as a natural antidote and are important anti-inflammatory and antioxidant agents in human diets. Polyphenols can prevent age-related diseases because they regulate complex networks of cellular processes such as oxidative damage, inflammation, cellular aging, and autophagy, and have also attracted wide attention as a potential beneficial substance for longevity. In this review, we systemically summarized the progress of targeting AMPK signaling by dietary polyphenols in aging prevention. Polyphenols can reduce oxidative stress and inflammatory response, and maintain the steady state of energy. Polyphenols can also modulate sirtuins/NAD+, nutrient-sensing, proteostasis, mitochondrial function, autophagy and senescence via targeting AMPK signaling. Therefore, targeting the AMPK signaling pathway by dietary polyphenols may be a novel anti-aging strategy.

Common pregnancy complications and polyphenols intake: an overview

During pregnancy, the body undergoes a great amount of changes in order to support a healthy developing fetus. In this context, maternal dietary supplementation is widely encouraged to provide adequate nutrition for the newborn. In the past few years, studies have emerged highlighting the benefits of polyphenols intake during pregnancy. Indeed, despite differences among reports, such as experimental model, polyphenol employed, dosage and regimen of administration, there is no doubt that the ingestion of these molecules has a protective effect in relation to three pregnancy-associated diseases or conditions: preeclampsia, gestational diabetes and fetal growth restriction. In this review, we describe the effects of different polyphenols and polyphenol-rich extracts or juices on the main outcomes of these common pregnancy-associated complications, obtained in human, animal and in vitro studies. Therefore, this work provides a critical analysis of the literature, and a summary of evidences, from which future research using polyphenols can be designed and evaluated.

The Aryl Hydrocarbon Receptor, Epigenetics and the Aging Process

The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor, classically associated with the regulation of xenobiotic metabolism in response to environmental toxins. In recent years, transgenic rodent models have implicated AhR in aging and longevity. Moreover, several AhR ligands, such as resveratrol and quercetin, are compounds proven to extend the lifespan of model organisms. In this paper, we first review AhR biology with a focus on aging and highlight several AhR ligands with potential anti-aging properties. We outline how AhR-driven expression of xenobiotic metabolism genes into old age may be a key mechanism through which moderate induction of AhR elicits positive benefits on longevity and healthspan. Furthermore, via integration of publicly available datasets, we show that liver-specific AhR target genes are enriched among genes subject to epigenetic aging. Changes to epigenetic states can profoundly affect transcription factor binding and are a hallmark of the aging process. We suggest that the interplay between AhR and epigenetic aging should be the subject of future research and outline several key gaps in the current literature. Finally, we recommend that a broad range of non-toxic AhR ligands should be investigated for their potential to promote healthspan and longevity.

Potential Properties of Natural Nutraceuticals and Antioxidants in Age-Related Eye Disorders

Eye health is crucial, and the onset of diseases can reduce vision and affect the quality of life of patients. The main causes of progressive and irreversible vision loss include various pathologies, such as cataracts, ocular atrophy, corneal opacity, age-related macular degeneration, uncorrected refractive error, posterior capsular opacification, uveitis, glaucoma, diabetic retinopathy, retinal detachment, undetermined disease and other disorders involving oxidative stress and inflammation. The eyes are constantly exposed to the external environment and, for this reason, must be protected from damage from the outside. Many drugs, including cortisonics and antinflammatory drugs have widely been used to counteract eye disorders. However, recent advances have been obtained via supplementation with natural antioxidants and nutraceuticals for patients. In particular, evidence has accumulated that polyphenols (mostly deriving from Citrus Bergamia) represent a reliable source of antioxidants able to counteract oxidative stress accompanying early stages of eye diseases. Luteolin in particular has been found to protect photoreceptors, thereby improving vision in many disease states. Moreover, a consistent anti-inflammatory response was found to occur when curcumin is used alone or in combination with other nutraceuticals. Additionally, Coenzyme Q10 has been demonstrated to produce a consistent effect in reducing ocular pressure, thereby leading to protection in patients undergoing glaucoma. Finally, both grape seed extract, rich in anthocyanosides, and polynsatured fatty acids seem to contribute to the prevention of retinal disorders. Thus, a combination of nutraceuticals and antioxidants may represent the right solution for a multi-action activity in eye protection, in association with current drug therapies, and this will be of potential interest in early stages of eye disorders.

Aging of mesenchymal stem cell: machinery, markers, and strategies of fighting

Human mesenchymal stem cells (MSCs) are primary multipotent cells capable of differentiating into osteocytes, chondrocytes, and adipocytes when stimulated under appropriate conditions. The role of MSCs in tissue homeostasis, aging-related diseases, and cellular therapy is clinically suggested. As aging is a universal problem that has large socioeconomic effects, an improved understanding of the concepts of aging can direct public policies that reduce its adverse impacts on the healthcare system and humanity. Several studies of aging have been carried out over several years to understand the phenomenon and different factors affecting human aging. A reduced ability of adult stem cell populations to reproduce and regenerate is one of the main  contributors to the human aging process. In this context, MSCs senescence is a major challenge in front of cellular therapy advancement. Many factors, ranging from genetic and metabolic pathways to extrinsic factors through various cellular signaling pathways, are involved in regulating the mechanism of MSC senescence. To better understand and reverse cellular senescence, this review highlights the underlying mechanisms and signs of MSC cellular senescence, and discusses the strategies to combat aging and cellular senescence.

DAF-16 is involved in colonic metabolites of ferulic acid-promoted longevity and stress resistance of Caenorhabditis elegans

BACKGROUND

Ferulic acid (FA) is a dietary polyphenol widely found in plant tissues. It has long been considered to have health-promoting qualities. However, the biological properties of dietary polyphenols depend largely on their absorption during digestion, and the effects of their intestinal metabolites on human health have attracted the interest of researchers. This study evaluated the effects of three main colonic metabolites of FA - 3-(3,4-dihydroxyphenyl)propionic acid (3,4diOHPPA), 3-(3-hydroxyphenyl)propionic acid (3OHPPA) and 3-phenylpropionic acid (3PPA) - on longevity and stress resistance in Caenorhabditis elegans.

RESULTS

Our results showed that 3,4diOHPPA, 3OHPPA and 3PPA extended the lifespan under normal conditions in C. elegans whereas FA did not. High doses of 3,4diOHPPA (0.5 mmol L^-1 ), 3OHPPA (2.5 mmol L^-1 ) and 3PPA (2.5 mmol L^-1 ) prolonged the mean lifespan by 11.2%, 13.0% and 10.6%, respectively. Moreover, 3,4diOHPPA, 3OHPPA and 3PPA treatments promoted stress tolerance against heat, UV irradiation and paraquat. Furthermore, three metabolites ameliorated physical functions, including reactive oxygen species and malondialdehyde levels, motility and pharyngeal pumping rate. The anti-aging activities mediated by 3,4diOHPPA, 3OHPPA and 3PPA depend on the HSF-1 and JNK-1 linked insulin/IGF-1 signaling pathway, which converge onto DAF-16.

CONCLUSION

The current findings suggest that colonic metabolites of FA have the potential for use as anti-aging bioactivate compounds. © 2022 Society of Chemical Industry.

From kitchen to clinic: Pharmacotherapeutic potential of common spices in Indian cooking in age-related neurological disorders

Aging is described as an advanced time-related collection of changes that may negatively affect with the risk of several diseases or death. Aging is a main factor of several age-related neurological disorders, including neurodegenerative diseases (Alzheimer’s disease, Parkinson’s disease, and dementia), stroke, neuroinflammation, neurotoxicity, brain tumors, oxidative stress, and reactive oxygen species (ROS). Currently available medications for age-related neurological disorders may lead to several side effects, such as headache, diarrhea, nausea, gastrointestinal (GI) diseases, dyskinesia, and hallucinosis. These days, studies on plant efficacy in traditional medicine are being conducted because herbal medicine is affordable, safe, and culturally acceptable and easily accessible. The Indian traditional medicine system called Ayurveda uses several herbs and medicinal plants to treat various disorders including neurological disorders. This review aims to summarize the data on the neuroprotective potential of the following common Indian spices widely used in Ayurveda: cumin (Cuminum cyminum (L.), Apiaceae), black cumin (Nigella sativa (L.), Ranunculaceae), black pepper (Piper nigrum (L.), Piperaceae), curry leaf tree (Murraya koenigii (L.), Spreng Rutaceae), fenugreek (Trigonella foenum-graecum (L.), Fabaceae), fennel (Foeniculum vulgare Mill, Apiaceae), cardamom (Elettaria cardamomum (L.) Maton, Zingiberaceae), cloves (Syzygium aromaticum (L.) Merr. & L.M.Perry, Myrtaceae), and coriander (Coriandrum sativum (L.), Apiaceae) in age-related neurological disorders.

Sirtuins as novel pharmacological targets in podocyte injury and related glomerular diseases

Podocyte injury is a major cause of proteinuria in kidney diseases, and persistent loss of podocytes leads to rapid irreversible progression of kidney disease. Sirtuins, a class of nicotinamide adenine dinucleotide-dependent deacetylases, can promote DNA repair, modify transcription factors, and regulate the cell cycle. Additionally, sirtuins play a critical role in renoprotection, particularly against podocyte injury. They also have pleiotropic protective effects on podocyte injury-related glomerular diseases, such as improving the immune inflammatory status and oxidative stress levels, maintaining mitochondrial homeostasis, enhancing autophagy, and regulating lipid metabolism. Sirtuins deficiency causes podocyte injury in different glomerular diseases. Studies using podocyte sirtuin-specific knockout and transgenic models corroborate this conclusion. Of note, sirtuin activators have protective effects in different podocyte injury-related glomerular diseases, including diabetic kidney disease, focal segmental glomerulosclerosis, membranous nephropathy, IgA nephropathy, and lupus nephritis. These findings suggest that sirtuins are promising therapeutic targets for preventing podocyte injury. This review provides an overview of recent advances in the role of sirtuins in kidney diseases, especially their role in podocyte injury, and summarizes the possible rationale for sirtuins as targets for pharmacological intervention in podocyte injury-related glomerular diseases.

Polyphenols and Small Phenolic Acids as Cellular Metabolic Regulators

Polyphenols and representative small phenolic acids and molecules derived from larger constituents are dietary antioxidants from fruits, vegetables and largely other plant-based sources that have ability to scavenge free radicals. What is often neglected in polyphenol metabolism is bioavailability and the role of the gut microbiota (GMB), which has an essential role in health and disease and participates in co-metabolism with the host. The composition of the gut microbiota is in constant flux and is modified by multiple intrinsic and extrinsic factors, including antibiotics. Dietary or other factors are key modulators of the host gut milieu. In this review, we explore the role of polyphenols and select phenolic compounds as metabolic or intrinsic biochemistry regulators and explore this relationship in the context of the microbiota–gut–target organ axis in health and disease.

Progress on the detoxification of aflatoxin B1 using natural anti-oxidants

Aflatoxins are toxic secondary metabolites produced by Aspergillus fungi. The most toxic among them is Aflatoxin B1 (AFB1) which is known to have genotoxic, immunotoxic, teratogenic, carcinogenic, and mutagenic toxic effects (amongst others). The mechanisms responsible for its toxicity include the induction of oxidative stress, cytotoxicity, and DNAdamage. Studies have found that natural anti-oxidants can reduce the damage that AFB1 inflicts on the body by alleviating oxidative stress and inhibiting the biotransformation of AFB1. Therefore, this review outlines the latest progress in research on the use of natural anti-oxidants as antidotes to aflatoxin poisoning and their detoxification mechanisms. It also considers the problems that may possibly arise from their use and their application prospects. Our aim is to provide a useful reference for the prevention and treatment of AFB1 poisoning.

Resveratrol Alleviating the Ovarian Function Under Oxidative Stress by Alternating Microbiota Related Tryptophan-Kynurenine Pathway

Oxidative stress (OS) is a key factor regulating the systemic pathophysiological effects and one of the fundamental mechanisms associated with aging and fertility deterioration. Previous studies revealed that resveratrol (RV) exhibits a preventive effect against oxidative stress in the ovary. However, it remains unknown whether gut microbiota respond to resveratrol during an OS challenge. In Exp. 1, layers received intraperitoneal injection of tert-butyl hydroperoxide (tBHP) (0 or 800 μmol/kg BW) or received resveratrol diets (0 or 600 mg/kg) for 28 days. In Exp. 2, the role of intestinal microbiota on the effects of resveratrol on tBHP-induced oxidative stress was assessed through fecal microbiota transplantation (FMT). The OS challenge reduced the egg-laying rate and exhibited lower pre-hierarchical follicles and higher atretic follicles. Oral RV supplementation ameliorated the egg-laying rate reduction and gut microbiota dysbiosis. RV also reversed the tryptphan-kynurenine pathway, upregulated nuclear factor E2-related factor 2 (Nrf2) and silent information regulator 1(SIRT1) levels, and decreased the expression of forkhead box O1 (FoxO1) and P53. These findings indicated that the intestinal microbiota-related tryptophan-kynurenine pathway is involved in the resveratrol-induced amelioration of ovary oxidative stress induced by tBHP in the layer model, while SIRT1-P53/FoxO1 and Nrf2-ARE signaling pathway were involved in this process.

Neuroprotective Effects of Resveratrol by Modifying Cholesterol Metabolism and Aβ Processing in SAMP8 Mice

Cholesterol metabolism seems dysregulated and linked to amyloid-β (Aβ) formation in neurodegeneration, but the underlying mechanisms are poorly known. Resveratrol (RSV) is a polyphenol with antioxidant activity and neuroprotective properties. Here, we analyzed the effect of age and RSV supplementation on cholesterol metabolism in the brain and blood serum, and its potential link to Aβ processing, in SAMP8 mice—an animal model of aging and Alzheimer’s disease. In the brain, our results revealed an age-related increase in ApoE and unesterified cholesterol in the plasma membrane whereas LDL receptor, HMG-CoA reductase, HMG-CoA-C1 synthase, and ABCA1 transporter remained unaltered. Furthermore, BACE-1 and APP gene expression was decreased. This dysregulation could be involved in the amyloidogenic processing pathway of APP towards Aβ formation. In turn, RSV exhibited an age-dependent effect. While levels of unesterified cholesterol in the plasma membrane were not affected by RSV, several participants in cholesterol uptake, release, and de novo synthesis differed, depending on age. Thus, RSV supplementation exhibited a different neuroprotective effect acting on Aβ processing or cholesterol metabolism in the brain at earlier or later ages, respectively. In blood serum, HDL lipoprotein and free cholesterol were increased by age, whereas VLDL and LDL lipoproteins remained unaltered. Again, the protective effect of RSV by decreasing the LDL or increasing the HDL levels also seems to depend on the intervention’s moment. In conclusion, age is a prominent factor for cholesterol metabolism dysregulation in the brain of SAMP8 mice and influences the protective effects of RSV through cholesterol metabolism and Aβ processing.

Resveratrol as a Promising Polyphenol in Age-Associated Cardiac Alterations

According to a widely accepted theory, oxidative stress is considered to be the number one trigger of aging-associated degenerative processes including cardiovascular diseases. In the context of aging-research, resveratrol receives special attention with its surprising number of health benefits. The aim of our study was to examine the anti-inflammatory and antioxidant effects of this dietary polyphenol in aging rat heart. 20-month-old female and male Wistar rats were divided into control (untreated) and resveratrol-treated groups. Resveratrol was administered at a dose of 0.05 mg/ml for 12 weeks dissolved in drinking water, while the control rats received ad libitum water. Cardiac level of reactive oxygen species (ROS), nuclear factor kappa B (NFκB), tumor necrosis factor alpha (TNF-α), and glutathione (GSH) parameters, as well as the activity of myeloperoxidase (MPO) and heme oxygenase (HO) enzymes were detected. Together with the biochemical measurements, hearts were isolated and used for an exposure of ischemic-reperfusion injury via Langendorff perfusion system. 12 week of resveratrol treatment suppressed the age-related inflammatory pathways including the expression of TNF-α, NFκB, and the activity of MPO while intensified the endogenous antioxidant defenses through the induction of GSH and HO system. Presumably, as a result of these processes, the necrotic area of the heart in response to an acute injury was also significantly reduced in the resveratrol-treated groups. Our findings confirmed that resveratrol has cardioprotective effects at several points by counteracting the aging-associated cellular malfunctions in the heart.

How Microbiomes Affect Skin Aging: The Updated Evidence and Current Perspectives

The skin has a multifactorial aging process, caused by both intrinsic and extrinsic factors. A major theory of aging involves cellular senescence or apoptosis resulting from oxidative damage as the skin’s antioxidant system tends to weaken with age. The human microbiota is a complex ecosystem that is made up of microorganisms (bacteria, fungi, and viruses). Both gut and skin microbiota have essential roles in the protection against invading pathogens, mediating inflammatory conditions, and the modulation of the immune system which is involved in both innate and adaptive immune responses. However, the human microbiome could be changed during the life stage and affected by various perturbations. An alteration of the intestinal bacteria results in “microbial dysbiosis” which is associated with the influence of various diseases, including aging. The skin interactome is a novel integration of the “genome-microbiome-exposome” that plays a significant role in skin aging and skin health. Mitigating the negative impacts of factors influencing the skin interactome should be the future strategy to protect, prevent, and delay skin aging along with preserving healthy skin conditions. This review summarizes the current evidence on how human microbiomes affect skin aging and demonstrates the possible interventions, relating to human microbiomes, to modulate skin health and aging. Probiotics-based products are currently available mainly for the add-on treatment of many dermatologic conditions. However, at this point, there are limited clinical studies on skin anti-aging purposes and more are required as this evolving concept is on the rise and might provide an insight into future therapeutic options.

Effects of curcumin and γ‑oryzanol solid dispersion on the brain of middle‑aged rats

Oxidative stress is one of the major factors that contributes to brain deterioration in the elderly. Oxidation causes molecular alterations, structural damage, and brain dysfunction, which includes cognitive impairment. Memory loss can begin in middle-aged individuals, so prevention of brain deterioration before aging is important. Several studies have reported that curcumin and γ-oryzanol exhibits anti-oxidant and anti-inflammatory properties. However, curcumin and γ-oryzanol exhibit low aqueous solubility. Thus, a solid dispersion technique was used to prepare curcumin and γ-oryzanol to enhance their solubility and stability. This study aims to evaluate the effects and mechanisms of γ-oryzanol solid dispersion (GOSD) and curcumin solid dispersion (CURSD) on learning and memory in six groups of male rats (n=5/group). Group one was the adult control consisting of 6-week old male rats, and the remaining five groups consisted of 42-week (middle-aged) male rats. The groups were labeled as the control group, the GO group (GOSD 10 mg/kg·BW), the Cur group (CURSD 50 mg/kg·BW), the GO-LCur group (GOSD 10 mg/kg·BW plus CURSD 25 mg/kg·BW), and the GO-HCur group (GOSD 10 mg/kg·BW plus CURSD 50 mg/kg·BW). Substances were administrated by oral gavage once daily for 42 consecutive days. The GO-HCur group exhibited significantly increased learning and memory performance in a Morris water maze and in reacting to a spontaneous tendency novel object test. The rats also exhibited decreased levels of lipid peroxidation, increased superoxide dismutase levels, glutathione peroxidase levels, catalase activity, and enhanced c-Fos expression both in the hippocampus and prefrontal cortex. The results indicated that GOSD 10 mg/kg plus CURSD 50 mg/kg was able to enhance learning and memory performance in the middle-aged rats.

Non-coding RNAs in photoaging-related mechanisms: a new paradigm in skin health

The aging of skin is a biological process affected by environmental or genetic factors. Exposure to ultraviolet (UV) radiation is the main environmental factor causing skin aging. Cumulative UV-induced photodamage of the skin tissue is associated with premature cellular senescence, extracellular degradation, and inflammatory responses in photoaging processes. Non-coding RNAs (ncRNAs) are untranslated transcripts and master regulators of protein-coding genes. ncRNAs have a critical regulatory role in maintaining skin structure, skin barrier function, morphogenesis, and development. Altered ncRNA expression has been reported in various skin disorders such as photoaging and skin cancers. ncRNAs contribute to the suppression and promotion of photoaging by modulating signaling pathways such as mitogen-activated protein kinase (MAPK) pathway and regulating inflammatory cytokines, matrix metalloproteinases (MMPs), and senescence-associated genes. Elucidation of the functions of ncRNAs will improve the identification of molecular mechanisms underlying photoaging, and can be used in the development of therapeutic approaches in skin health and prevention of sun-induced aging. This review summarized the currently described ncRNAs and their functions in photoaging.

Flavonoids as Sirtuin Modulators

Sirtuins (SIRTs) are described as NAD+-dependent deacetylases, also known as class III histone deacetylases. So far, seven sirtuin genes (SIRTS 1-7) have been identified and characterized in mammals and also known to occur in bacteria and eukaryotes. SIRTs are involved in various biological processes including endocrine system, apoptosis, aging and longevity, diabetes, rheumatoid arthritis, obesity, inflammation, etc. Among them, the best characterized one is SIRT1. Actually, small molecules seem to be the most effective SIRT modulators. Flavonoids have been reported to possess many positive effects favrable for human health, while a relatively less research has been reported so far on their funcions as SIRT modulation mechanisms. In this regard, we herein aimed to focus on modulatory effects of flavonoids on SIRTs as the most common secondary metabolites in natural products. Our literature survey covering the years of 2006-2021 pointed out that flavonoids frequently interact with SIRT1 and SIRT3 followed by SIRT6. It can be also concluded that some popular flavonoid derivatives, e.g. resveratrol, quercetin, and catechin derivatives came forward in terms of SIRT modulation.