Autophagy and the hallmarks of aging

Autophagy: The convergence point of aging and cancer

Autophagy, a dynamic intracellular degradation system, is critical for cellular renovation and maintaining equilibrium. By eliminating damaged components and recycling essential molecules, autophagy safeguards cellular integrity and function. The versatility of the autophagy process across various biological functions enable cells to adapt and maintain homeostasis under unfavourable conditions. Disruptions in autophagy can shift a cell from a healthy state to a disease state or, conversely, support a return to health. This review delves into the multifaceted role of autophagy during aging and age-related diseases such as cancer, highlighting its significance as a unifying target with promising therapeutic implications. Cancer development is a dynamic process characterized by the acquisition of diverse survival capabilities for proliferating at different stages. This progression unfolds over time, with cancer cells exploiting autophagy to overcome encountered stress conditions during tumor development. Notably, there are several common pathways that utilize the autophagy process during aging and cancer development. This highlights the importance of autophagy as a crucial therapeutic target, holding the potential to not only impede the growth of tumor but also enhance the patient's longevity. This review aims to simplify the intricate relationship between cancer and aging, with a particular focus on the role of autophagy.

Exploring the impact of Gastrodin on brain aging in mice: Unraveling mechanisms through network pharmacology

BACKGROUND

With the intensification of global aging, slowing down the aging process has become a topic of significant interest. Brain aging, as one of the prominent changes in the aging process, urgently requires the exploration of new therapeutic methods to delay its progression. Gastrodia, a traditional Chinese medicine, has been widely recognized for its medicinal value, particularly in its pronounced neuroprotective effects. Although previous studies have demonstrated the protective effects of Gastrodin (GAS), an active compound in Gastrodia, on the mouse nervous system, its underlying mechanisms remain unclear.

OBJECTIVE

This study aims to investigate comprehensively the impact and mechanisms of GAS in delaying brain aging through the combined approach of network pharmacology and animal experiments, providing a theoretical basis for the clinical application of GAS in treating age-related decline.

METHODS

A D-galactose (D-gal)-induced aging mouse model was employed, and the anti-aging effects of GAS were evaluated through behavioral experiments and morphological observations. A "compound-target-pathway" network was constructed using network pharmacology. Gene and protein expression related to potential targets and pathways were verified and analyzed using RT-qPCR and immunohistochemistry (IHC) methods.

RESULTS

GAS exposure significantly alleviated signs of brain aging in mice, including reduced body weight index, improved behavioral memory, mitigation of hippocampal morphological damage due to aging, and relief of oxidative stress levels in the mouse brain. Target screening through network pharmacology identified four key targets related to the AMPK/mTOR pathway and autophagy: AMPK, ULK1, ATG5, and Beclin1. Validation of the network pharmacology results using RT-qPCR and IHC confirmed that GAS upregulates cellular autophagy levels through the AMPK/mTOR/ULK1 signaling pathway.

CONCLUSION

GAS demonstrates a pronounced alleviating effect on age-related symptoms in D-galactose-induced brain aging mice by suppressing oxidative stress in the mouse brain. The mechanism involves the upregulation of cellular autophagy through the AMPK/mTOR/ULK1 signaling pathway.

Aging and Lifestyle Modifications for Preventing Aging-Related Diseases

The pathogenesis of various chronic diseases is closely associated with aging. Aging of the cardiovascular system promotes the development of severe cardiovascular diseases with high mortality, including atherosclerosis, coronary heart disease, and myocardial infarction. Similarly, aging of the nervous system promotes the development of neurodegenerative diseases, such as Alzheimer's disease, which seriously impairs cognitive function. Aging of the musculoskeletal system is characterized by decreased function and mobility. The molecular basis of organ aging is cellular senescence, which involves multiple cellular and molecular mechanisms, such as impaired autophagy, metabolic imbalance, oxidative stress, and persistent inflammation. Given the ongoing demographic shift toward an aging society, strategies to delay or reduce the effects of aging have gained significance. Lifestyle modifications, such as exercise and calorie restriction, are now recognized for their anti-aging effects, their capacity to reduce modification, their potential to prolong lifespan, and their capacity to lower the risk of cardiovascular disease. This review elucidates the molecular mechanisms and application significance of various anti-aging approaches at the molecular level, based on research progress in aging. It aims to provide a reference for the prevention and treatment of age-related diseases in progressively aging societies.

SQSTM1/p62 Orchestrates Skin Aging via USP7 Degradation

Skin aging is a complex process driven by intrinsic genetic factors and extrinsic environmental influences. In this study, sequestosome1 (SQSTM1/p62) was identified as a key regulator of senescence, the senescence-associated secretory phenotype (SASP), and skin aging. Notably, p62 expression is reduced in senescent cells and aging skin of both humans and mice. The depletion of p62 in the epidermis was found to be positively associated with accelerated aging and the initiation of SASP. Mechanistically, p62 inhibits the accumulation of ubiquitin-specific protease 7 (USP7) during senescence induction by orchestrating its degradation through specific binding interactions. In particular, the Tyr-67 residue within the PB1 domain or Gln-418 within the UBA domain of p62 forms a hydrogen bond with Ala-993 in the Ubl5 domain of USP7. Mutations in either Tyr-67 or Gln-418 of p62, or Ala-993 of USP7, resulted in the induction of cellular senescence, highlighting the critical role of these molecular interactions in the regulation of aging processes.

Rapamycin and Post-Deficiency Dietary Recovery Reshape Antioxidant Response and Survival in Offspring of Iron-Deficient Mothers

Maternal iron deficiency (ID) disrupts maternal and offspring health by impairing iron status and antioxidant defenses. Rapamycin is known to promote autophagy, enhance antioxidant activity, and extend lifespan. This study investigates the intergenerational effects of post-deficiency dietary interventions using normal and rapamycin-treated diets on Drosophila melanogaster. Female flies (F0) were subjected to an iron-deficient diet for 14 days, followed by a 30-day recovery period on either a normal diet or a rapamycin-supplemented diet. Some F0 females were subsequently mated with normal males to produce F1 offspring. Physiological, biochemical, and gene expression analyses were conducted on F0 flies post-chelation and post-intervention. Post-eclosion evaluations, including a 60-day survival study, were performed on both generations. In F0 females, iron chelation significantly reduced (p < 0.0001) body weight, iron levels, and antioxidant enzyme activity, while increasing glutathione (GSH) levels. Gene expression analysis revealed significant changes (p < 0.05) in iron storage (Fer1HCH), autophagy (ATG1), and telomere-related genes (dHeT-A, dTahre, dTart). While a normal diet partially restored iron levels and survival, the rapamycin-treated diet improved antioxidant defenses but had mixed effects on survival and gene expression. In the F1 generation, male and female offspring from mothers on a normal diet exhibited reduced and increased iron levels, respectively, alongside improved median survival. Rapamycin increased body weight and iron levels in female offspring but reduced their median survival. Post-deficiency dietary interventions significantly shape antioxidant responses and survival in both iron-deficient mothers and their offspring. While normal diets support recovery of iron status, rapamycin enhances antioxidant defenses but compromises survival, particularly in female offspring.

The biomedical application of inorganic metal nanoparticles in aging and aging-associated diseases

Aging and aging-associated diseases (AAD), including neurodegenerative disease, cancer, cardiovascular diseases, and diabetes, are inevitable process. With the gradual improvement of life style, life expectancy is gradually extended. However, the extended lifespan has not reduced the incidence of disease, and most elderly people are in ill-health state in their later years. Hence, understanding aging and AAD are significant for reducing the burden of the elderly. Inorganic metal nanoparticles (IMNPs) predominantly include gold, silver, iron, zinc, titanium, thallium, platinum, cerium, copper NPs, which has been widely used to prevent and treat aging and AAD due to their superior properties (essential metal ions for human body, easily synthesis and modification, magnetism). Therefore, a systematic review of common morphological alternations of senescent cells, altered genes and signal pathways in aging and AAD, and biomedical applications of IMNPs in aging and AAD is crucial for the further research and development of IMNPs in aging and AAD. This review focus on the existing research on cellular senescence, aging and AAD, as well as the applications of IMNPs in aging and AAD in the past decade. This review aims to provide cutting-edge knowledge involved with aging and AAD, the application of IMNPs in aging and AAD to promote the biomedical application of IMNPs in aging and AAD.

Normative aging results in degradation of gene networks in a zebra finch basal ganglia nucleus dedicated to vocal behavior

Aging increases brain susceptibility to neurodegenerative diseases, but the mechanisms are not clear. Vocal behavior provides an accessible, reliable, and sensitive biomarker to address this because voice changes in middle age can be early indicators of neurodegenerative diseases. The adult male zebra finch is an excellent model organism for these studies due to well-characterized vocal brain circuitry and strong homology to human brain centers. We performed RNA sequencing of song-dedicated basal ganglia nucleus Area X followed by weighted gene co-expression network analyses to examine changes in gene patterns across younger adult, middle, and older ages. Song-correlated gene networks degrade with age, with modules losing their coherence and migrating to different sets of genes, and changes in connection strength particularly for hub genes including those associated with human speech, Parkinson's, and Alzheimer's diseases. Gene pathway enrichment analyses reveal a lack of ongoing metabolic and biogenic processes in older finches. Our findings provide a robust platform for targeting network hubs in the treatment of neurologically driven human vocal disorders.

Tricin Delays Aging and Enhances Muscle Function via Activating AMPK-Mediated Autophagy in Diverse Model Organisms

Aging leads to progressive decline in the functions of cells, tissues, and organs, severely affecting muscle performance and overall health, highlighting the urgent need for effective therapeutic agents. This study investigated the antiaging properties of tricin, a flavonoid abundant in grains, using biological models, including human fibroblasts, Caenorhabditis elegans (C. elegans), and mice. Tricin significantly alleviated the senescent phenotype in human fibroblasts induced by D-galactose (D-gal), doxorubicin, and replicative senescence, as evidenced by reduced SA-β-gal activity, downregulated senescence markers (p16, p21), and decreased SASP factors. Mechanistically, tricin binds to AMPK and activates the AMPK-mTOR-p70S6K signaling pathway, promoting autophagy and delaying cellular aging. In vivo, tricin extended lifespan, enhanced stress resistance, and improved mobility in C. elegans through aak-2/AMPK-mediated autophagy. In D-gal-induced aging mice, tricin improved muscle function, reducing p16, p21, and SASP expression in muscle tissues. These findings underscore tricin's potential as a promising antiaging therapeutic via AMPK-mediated autophagy activation.

Curcumin ameliorates aging-induced blood-testis barrier disruption by regulating AMPK/mTOR mediated autophagy

The blood-testis barrier (BTB) is composed of tight junctions (TJ) between adjacent Sertoli cells (SCs) and is crucial for sperm growth and development. Aging-induced TJ impairment is closely related to testicular dysfunction. Curcumin, a natural compound, has been widely demonstrated to have a wide range of pharmacological activities, but its regulatory effects on tight junction damage in the testis remain unclear. We here explored the effect of curcumin on TJ function and its underlying molecular mechanism by using D-galactose (D-gal)-induced mouse testis and mouse testicular SCs (TM4) aging models in vitro. In this study, D-gal increased the expression of aging-related proteins p16 and p21, whereas significantly decreased the expression of TJ proteins (ZO-1, Claudin-4, Claudin-7, and Occludin). In addition, curcumin restored the adverse effects of D-gal in the SCs. Autophagy is a degradation system for maintaining cell renewal and homeostasis. D-gal significantly decreased the autophagy level, whereas curcumin restored the effect of D-gal. Using chloroquine (CQ), an inhibitor of autophagy, and rapamycin (RAPA), an activator of autophagy, it was demonstrated that autophagy plays a key role in curcumin amelioration of TJ injury in testicular SCs. Further studies unveiled that autophagy activation was mediated through the AMPK/mTOR pathway. In conclusion, curcumin ameliorates aging-induced TJ damage through AMPK/mTOR signaling pathway-regulated autophagy. This study thus clearly identifies a novel action mechanism of curcumin in the treatment of age-related male reproductive disorders.

From geroscience to precision geromedicine: Understanding and managing aging

Major progress has been made in elucidating the molecular, cellular, and supracellular mechanisms underlying aging. This has spurred the birth of geroscience, which aims to identify actionable hallmarks of aging. Aging can be viewed as a process that is promoted by overactivation of gerogenes, i.e., genes and molecular pathways that favor biological aging, and alternatively slowed down by gerosuppressors, much as cancers are caused by the activation of oncogenes and prevented by tumor suppressors. Such gerogenes and gerosuppressors are often associated with age-related diseases in human population studies but also offer targets for modeling age-related diseases in animal models and treating or preventing such diseases in humans. Gerogenes and gerosuppressors interact with environmental, behavioral, and psychological risk factors to determine the heterogeneous trajectory of biological aging and disease manifestation. New molecular profiling technologies enable the characterization of gerogenic and gerosuppressive pathways, which serve as biomarkers of aging, hence inaugurating the era of precision geromedicine. It is anticipated that, pending results from randomized clinical trials and regulatory approval, gerotherapeutics will be tailored to each person based on their genetic profile, high-dimensional omics-based biomarkers of aging, clinical and digital biomarkers of aging, psychosocial profile, and past or present exposures.

Conserved components of the macroautophagy machinery in Caenorhabditis elegans

Macroautophagy involves the sequestration of cytoplasmic contents in a double-membrane autophagosome and its subsequent delivery to lysosomes for degradation and recycling. In Caenorhabditis elegans, autophagy participates in diverse processes such as stress resistance, cell fate specification, tissue remodeling, aging, and adaptive immunity. Genetic screens in C. elegans have identified a set of metazoan-specific autophagy genes that form the basis for our molecular understanding of steps unique to the autophagy pathway in multicellular organisms. Suppressor screens have uncovered multiple mechanisms that modulate autophagy activity under physiological conditions. C. elegans also provides a model to investigate how autophagy activity is coordinately controlled at an organismal level. In this chapter, we will discuss the molecular machinery, regulation, and physiological functions of autophagy, and also methods utilized for monitoring autophagy during C. elegans development.

Neddylation modification stabilizes LC3B by antagonizing its ubiquitin-mediated degradation and promoting autophagy in skin

The Atg8-family proteins, including LC3B (microtubule-associated protein 1 light chain 3 beta), are pivotal for key steps in the autophagy process. Proper regulation of LC3B homeostasis is essential for its function. Although LC3B is modulated by various posttranslational modifications (PTMs), the impact of these modifications on LC3B protein homeostasis remains unclear. Neddylation, a recently identified ubiquitin-like modification, plays diverse biological roles. Here, we identify LC3B as a specific target for neddylation. This modification weakens LC3B's interaction with the ubiquitin E3 ligases VHL and BIRC6, thereby reducing LC3B ubiquitination. Depletion of ubiquitin-conjugating enzyme E2M (UBE2M), the primary E2 enzyme in the neddylation pathway, destabilizes LC3B and suppresses autophagy activity. Heterozygous Ube2m knockout (Ube2m+/-) mice exhibit pronounced aging-like phenotypes, with reduced LC3B expression and impaired autophagy in skin tissues. Our findings demonstrate that LC3B neddylation is vital for maintaining its stability and regulating autophagy flux, offering a potential therapeutic avenue to mitigate aging-related processes.

Proteostasis and lysosomal repair deficits in transdifferentiated neurons of Alzheimer's disease

Ageing is the most prominent risk factor for Alzheimer's disease (AD). However, the cellular mechanisms linking neuronal proteostasis decline to the characteristic aberrant protein deposits in the brains of patients with AD remain elusive. Here we develop transdifferentiated neurons (tNeurons) from human dermal fibroblasts as a neuronal model that retains ageing hallmarks and exhibits AD-linked vulnerabilities. Remarkably, AD tNeurons accumulate proteotoxic deposits, including phospho-tau and amyloid β, resembling those in APP mouse brains and the brains of patients with AD. Quantitative tNeuron proteomics identify ageing- and AD-linked deficits in proteostasis and organelle homeostasis, most notably in endosome-lysosomal components. Lysosomal deficits in aged tNeurons, including constitutive lysosomal damage and ESCRT-mediated lysosomal repair defects, are exacerbated in AD tNeurons and linked to inflammatory cytokine secretion and cell death. Providing support for the centrality of lysosomal deficits in AD, compounds ameliorating lysosomal function reduce amyloid β deposits and cytokine secretion. Thus, the tNeuron model system reveals impaired lysosomal homeostasis as an early event of ageing and AD.

The Role of Ginseng and Its Bioactive Compounds in Aging: Cells and Animal Studies

Aging is an inevitable process that is characterized by physiological deterioration and increased vulnerability to stressors. Therefore, the interest in hallmarks, mechanisms, and ways to delay or prevent aging has grown for decades. Natural plant products and their bioactive compounds have been studied as a promising strategy to overcome aging. Ginseng, a traditional herbal medicine, and its bioactive compound, the ginsenosides, have increasingly gained attention because of various pharmacological functions. This review introduces the species, useful parts, characteristics, and active components of ginseng. It primarily focuses on the bioconversion of ginsenosides through the unique steaming and drying process. More importantly, this review enumerates the antiaging mechanisms of ginseng, ginsenosides, and other bioactive compounds, highlighting their potential to extend the health span and mitigate age-related diseases based on twelve representative hallmarks of aging.

Age-Related Impairments in Immune Cell Efferocytosis and Autophagy Hinder Atherosclerosis Regression

BACKGROUND

Aging is a well-established risk factor for the development and progression of atherosclerosis, but the molecular mechanisms underlying this relationship remain poorly defined, and its role in atherosclerosis regression is unknown. To uncover age-related alterations that may impair atherosclerosis regression, we investigated the response of young and old macrophages to atherogenic lipoproteins in vitro and in vivo.

METHODS

Metabolic and proteomic studies were performed in vitro using macrophages differentiated from the bone marrow of young or old mice. To test the role of immune cell aging in atherosclerosis regression, bone marrow from young and old donors was transplanted into irradiated young recipient mice expressing gain-of-function AAV-PCSK9 (adeno-associated virus-proprotein convertase subtilisin/kexin type 9). Following 14 weeks of Western diet feeding, atherosclerosis regression was induced by switching to a standard laboratory diet for 4 weeks.

RESULTS

Compared with young macrophages, old macrophages accumulated more lipid droplets upon lipid loading with the pro-atherogenic lipoprotein aggregated LDL (low-density lipoprotein), accompanied by a failure to proportionally induce autophagy and cholesterol efflux. Proteomic analysis of bone marrow-derived macrophages revealed that pathways related to endocytosis, engulfment, and phagocytosis were downregulated in old lipid-loaded macrophages. Functional studies confirmed a reduction in efferocytic capacity in old macrophages. In recipient mice transplanted with old bone marrow, atherosclerosis regression was impaired, as evidenced by inefficient resolution of circulating inflammatory cell levels, reduced activation of plaque autophagy and apoptotic cell clearance, and persistent plaque CD45+ and CD68+ content.

CONCLUSIONS

Aging impairs macrophage function through reduced efferocytosis and autophagy activation, limiting atherosclerosis regression. These results highlight the need to better define the mechanisms linking aging to atherosclerosis to develop targeted therapies for the aging population.

Sex-specific and cell-type-specific changes in chaperone-mediated autophagy across tissues during aging

Aging leads to progressive decline in organ and tissue integrity and function, partly due to loss of proteostasis and autophagy malfunctioning. A decrease with age in chaperone-mediated autophagy (CMA), a selective type of lysosomal degradation, has been reported in various organs and cells from rodents and humans. Disruption of CMA recapitulates features of aging, whereas activating CMA in mice protects against age-related diseases such as Alzheimer's, retinal degeneration and/or atherosclerosis. However, sex-specific and cell-type-specific differences in CMA with aging remain unexplored. Here, using CMA reporter mice and single-cell transcriptomic data, we report that most organs and cell types show CMA decline with age, with males exhibiting a greater decline with aging. Reduced CMA is often associated with fewer lysosomes competent for CMA. Transcriptional downregulation of CMA genes may further contribute to CMA decline, especially in males. These findings suggest that CMA differences may influence organ vulnerability to age-related degeneration.

Asparagine prevents intestinal stem cell aging via the autophagy-lysosomal pathway

The age-associated decline in intestinal stem cell (ISC) function is a key factor in intestinal aging in organisms, resulting in impaired intestinal function and increased susceptibility to age-related diseases. Consequently, it is imperative to develop effective therapeutic strategies to prevent ISC aging and functional decline. In this study, we utilized an aging Drosophila model screening of amino acids and found that asparagine (Asn), a nonessential amino acid in vivo, exhibits its profound anti-aging properties on ISCs. Asn inhibits the hyperproliferation of aging ISCs in Drosophila, maintains intestinal homeostasis, and extends the lifespan of aging flies. Complementarily, Asn promotes the growth and branching of elderly murine intestinal organoids, indicating its anti-aging capacity to enhance ISC function. Mechanistic analyses have revealed that Asn exerts its effects via the activation of the autophagic signaling pathway. In summary, this study has preliminarily explored the potential supportive role of Asn in ameliorating intestinal aging, providing a foundation for further research into therapeutic interventions targeting age-related intestinal dysfunction.

Ellagic acid alleviates PM2.5-induced senescence of lung epithelial cells by mediating autophagy

Fine particulate matter (PM2.5) exposure is significantly linked to lung epithelial cell senescence, and autophagy dysfunction being a key contributor to the aging process. Although the anti-aging properties of ellagic acid (EA) are well-documented, its specific protective effect on PM2.5-induced lung epithelial cell senescence still needs to be studied in depth. To investigate the impacts of PM2.5 on autophagy and senescence in lung epithelial cells, 16HBE and A549 cells were exposed to PM2.5 suspension. Additionally, to explore the potential intervention effect of EA, cells were pretreated with EA before exposure to PM2.5 suspension. Cell morphology, proliferation, senescence-related markers, senescence-associated secretory phenotype (SASP), and autophagy-related markers were then assessed. Our results showed that the proliferation of 16HBE and A549 cells were inhibited and autophagy dysfunction and senescence were induced under PM2.5 exposure. However, pretreatment with EA can significantly improve the obstruction of autophagy flux caused by PM2.5, thereby effectively alleviating cell senescence. This study reveals the mechanism by which PM2.5 induces senescence in lung epithelial cells and confirms the protective role of ellagic acid in this process.

The Probiotic Yeast, Milmed, Promotes Autophagy and Antioxidant Pathways in BV-2 Microglia Cells and C. elegans

Background: Autophagy, a catabolic process essential for maintaining cellular homeostasis, declines with age and unhealthy lifestyles, contributing to neurodegenerative diseases. Probiotics, including Milmed yeast, have demonstrated anti-inflammatory and antioxidant properties. This study evaluated the activity of Milmed on BV-2 microglial cells in vitro and in the in vivo model of Caenorhabditis elegans (C. elegans) in restoring autophagic processes. Methods: BV-2 microglial cells were incubated with S. cerevisiae (Milmed treated yeast or untreated yeast) and then stimulated with lipopolysaccharide (LPS). mRNAs of the autophagic factors and antioxidant enzymes were assessed by qPCR; mTOR and NRF2 were evaluated by ELISA. pNRF2 compared with cytosolic NRF2 was evaluated by immunofluorescence. The longevity, body size, and reactive oxygen species (ROS) levels of C. elegans were measured by fluorescence microscopy. Results: Treatment with Milmed YPD cultured yeast or the dried powder obtained from it promoted autophagic flux, as shown by the increased expression of the Beclin-1, ATG7, LC3, and p62 mRNAs and the inhibition of mTOR, as evaluated by ELISA. It also enhanced the antioxidant response by increasing the expression of NRF2, SOD1, and GPX; moreover, pNRF2 expression compared with cytosolic NRF2 expression was enhanced, as shown by immunofluorescence. Milmed dietary supplementation prolonged the survival of C. elegans and reduced the age-related ROS accumulation without changing the expression of gst-4. The pro-longevity effect was found to be dependent on SKN-1/Nrf2 activation, as shown by the absence of benefit in skn-1 mutants. Conclusions: Milmed yeast demonstrates significant pro-autophagy and antioxidant activity with significant pro-longevity effects in C. elegans, thereby extending the lifespan and improving stress resistance, which, together with the previously demonstrated anti-inflammatory activity, highlights its role as a highly effective probiotic for its beneficial health effects. Activation of the SKN-1/NRF2 pathway and the modulation of autophagy support the therapeutic potential of Milmed in neuroprotection and healthy aging.

Interplay Between Polyphenols and Autophagy: Insights From an Aging Perspective

The relationship between polyphenols and autophagy, particularly in the context of aging, presents a promising avenue for therapeutic interventions in age-related diseases. A decline in autophagy is associated with aging-related affections, and an increasing number of studies suggest that this enhancement is linked to cellular resilience and longevity. This review delves into the multifaceted roles of autophagy in cellular homeostasis and the potential of polyphenols to modulate autophagic pathways. We revised the most updated literature regarding the modulatory effects of polyphenols on autophagy in cardiovascular, liver, and kidney diseases, highlighting their therapeutic potential. We highlight the role of polyphenols as modulators of autophagy to combat age-related diseases, thus contributing to improving the quality of life in aging populations. A better understanding of the interplay of autophagy between autophagy and polyphenols will help pave the way for future research and clinical applications in the field of longevity medicine.

Systemic aging and aging-related diseases

Aging is a biological process along with systemic and multiple organ dysfunction. It is more and more recognized that aging is a systemic disease instead of a single-organ functional disorder. Systemic aging plays a profound role in multiple diseases including neurodegenerative diseases, cardiovascular diseases, and malignant diseases. Aged organs communicate with other organs and accelerate aging. Skeletal muscle, heart, bone marrow, skin, and liver communicate with each other through organ-organ crosstalk. The crosstalk can be mediated by metabolites including lipids, glucose, short-chain fatty acids (SCFA), inflammatory cytokines, and exosomes. Metabolic disorders including hyperglycemia, hyperinsulinemia, and hypercholesterolemia caused by chronic diseases accelerate hallmarks of aging. Systemic aging leads to the destruction of systemic hemostasis, causes the release of inflammatory cytokines, senescence-associated secretory phenotype (SASP), and the imbalance of microbiota composition. Released inflammatory factors further aggregate senescence, which promotes the aging of multiple solid organs. Targeting senescence or delaying aging is emerging as a critical health strategy for solving age-related diseases, especially in the old population. In the current review, we will delineate the mechanisms of organ crosstalk in systemic aging and age-related diseases to provide therapeutic targets for delaying aging.

Anthraquinones and Aloe Vera Extracts as Potential Modulators of Inflammaging Mechanisms: A Translational Approach from Autoimmune to Onco-Hematological Diseases

Inflammaging is a chronic, low-grade inflammatory state that contributes to age-related diseases, including cardiovascular disorders, osteoporosis, neurodegeneration, and cancer. This process involves immunosenescence, oxidative stress, and immune aging, all of which contribute to the breakdown of immune tolerance and the onset of autoimmune disorders. Aloe vera (AV) has recently gained attention for its immunomodulatory, anti-inflammatory, and antioxidant properties. This review explores the effects of AV extracts and anthraquinones (e.g., aloe-emodin, emodin, aloin) on key inflammaging-driven mechanisms in autoimmunity. Our analysis highlights AV's ability to regulate hormone balance, autoantibody production, and cytokine/chemokine signaling (such as interleukin-1β, tumor necrosis factor-α, and interferon-γ). It modulates inflammatory pathways, including mitogen-activated protein kinases (MAPKs) and phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT), thereby inhibiting nuclear factor kappa-light-chain-enhancer of activated B-cell (NF-κB) activation. Additionally, AV enhances antioxidant defenses and restores immune balance by reducing Th1/Th17 subsets while promoting Th2-mediated regulation. Notably, AV also modulates inflammasome-mediated mechanisms and counteracts immunosenescence, which is driven by autophagy-related processes. These effects position AV as a potential integrative approach to mitigating inflammaging-driven autoimmunity. Furthermore, as inflammaging is increasingly recognized in onco-hematological diseases, AV-based strategies may offer novel therapeutic avenues. Future studies should focus on clinical validation, optimizing formulations, and expanding applications to broader age-related and immune-mediated disorders.

Redox regulation: mechanisms, biology and therapeutic targets in diseases

Redox signaling acts as a critical mediator in the dynamic interactions between organisms and their external environment, profoundly influencing both the onset and progression of various diseases. Under physiological conditions, oxidative free radicals generated by the mitochondrial oxidative respiratory chain, endoplasmic reticulum, and NADPH oxidases can be effectively neutralized by NRF2-mediated antioxidant responses. These responses elevate the synthesis of superoxide dismutase (SOD), catalase, as well as key molecules like nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione (GSH), thereby maintaining cellular redox homeostasis. Disruption of this finely tuned equilibrium is closely linked to the pathogenesis of a wide range of diseases. Recent advances have broadened our understanding of the molecular mechanisms underpinning this dysregulation, highlighting the pivotal roles of genomic instability, epigenetic modifications, protein degradation, and metabolic reprogramming. These findings provide a foundation for exploring redox regulation as a mechanistic basis for improving therapeutic strategies. While antioxidant-based therapies have shown early promise in conditions where oxidative stress plays a primary pathological role, their efficacy in diseases characterized by complex, multifactorial etiologies remains controversial. A deeper, context-specific understanding of redox signaling, particularly the roles of redox-sensitive proteins, is critical for designing targeted therapies aimed at re-establishing redox balance. Emerging small molecule inhibitors that target specific cysteine residues in redox-sensitive proteins have demonstrated promising preclinical outcomes, setting the stage for forthcoming clinical trials. In this review, we summarize our current understanding of the intricate relationship between oxidative stress and disease pathogenesis and also discuss how these insights can be leveraged to optimize therapeutic strategies in clinical practice.

Gerobiotics: Exploring the Potential and Limitations of Repurposing Probiotics in Addressing Aging Hallmarks and Chronic Diseases

As unhealthy aging continues to rise globally, there is a pressing need for effective strategies to promote healthy aging, extend health span, and address aging-related complications. Gerobiotics, an emerging concept in geroscience, offers a novel approach to repurposing selective probiotics, postbiotics, and parabiotics to modulate key aging processes and enhance systemic health. This review explores recent advancements in gerobiotics research, focusing on their role in targeting aging hallmarks, regulating longevity-associated pathways, and reducing risks of multiple age-related chronic conditions. Despite their promise, significant challenges remain, including optimizing formulations, ensuring safety and efficacy across diverse populations, and achieving successful clinical translation. Addressing these gaps through rigorous research, well-designed clinical trials, and advanced biotechnologies can establish gerobiotics as a transformative intervention for healthy aging and chronic disease prevention.

Chronic moderate‑intensity exercise can induce physiological hypertrophy in aged cardiomyocytes through autophagy, with minimal Yap/Taz involvement

Aging is known to cause increased comorbidities associated with cardiovascular decline. Physical exercises were known to be an effective intervention for the age-associated decline in cardiac function. Exercise caused physiological hypertrophy influenced by Yap/Taz, autophagy and myosin heavy chain (MHC) dynamics. However, whether exercise-induced changes are associated with aging has yet to be determined. The present study explored the effects of moderate-intensity exercises on autophagy, MHC dynamics, and Yap/Taz activity to understand their complex interactions at the molecular effects on the cardiac function of aging cardiac tissue. The present study used male Wistar (Rattus norvegicus) rats (80 weeks-old) randomly divided into two groups (n=12): control and intervention. The intervention group was given an intervention using an animal treadmill. After 8 weeks, the animal was sacrificed, and data were collected. Statistical analysis was conducted using an independent t-test or Mann-Whitney U test when appropriate. Exercise in aged rats can induce physiological hypertrophy, as shown by gross measurement and histological features. Yap/Taz did not mediate the effects of exercise on hypertrophy. Autophagy function was shown to increase, which may cause the low expression of Yap/Taz. In conclusion, exercise is a viable intervention in increasing heart mass and potentially delaying the decline in function associated with aging.

Does the Combination of Metabolic Syndrome and Low Fat-Free Mass Shorten an Individual's Disability-Free Life? A 12-Year Prospective Cohort Study of the Korean Genome and Epidemiology Study (KoGES)

OBJECTIVE

This study aims to explore the combined risk of metabolic syndrome (MetS) and low fat-free mass (FFM) on an individual's disability-free survival (DFS). Disability is defined as a composite of dementia, physical disability, and mortality.

METHODS

Using data from the Korean Genome and Epidemiology Study, we divided 3721 participants aged 40-69 years based on their MetS status and FFM index (FFMI) score. Kaplan-Meier survival analysis and Cox regression were used to analyze differences in DFS between the four groups.

RESULTS

From 108 events, MetS group had significantly shorter DFS than the non-MetS group regardless of FFMI (p < 0.0001). After adjusting other potential confounding variables, the MetS group had a higher risk of shortened DFS regardless of FFMI, and the MetS group with low FFMI had a 2.06-fold increased risk compared to the non-MetS group with high FFMI (p < 0.001). Older age and lower income were also associated with higher risk of shorter DFS (p < 0.001).

CONCLUSIONS

The combination of MetS and low FFMI contribute to a cumulative risk of shortened DFS. Community nurses can perform MetS screening and body composition assessment to predict and control the risk of developing disability over time.

Autophagy-dependent splicing control directs translation toward inflammation during senescence

The cellular proteome determines the functional state of cells and is often skewed to direct pathological conditions. Autophagy shapes cellular proteomes primarily through lysosomal degradation of either damaged or unnecessary proteins. Here, we show that autophagy directs the senescence-specific translatome to fuel inflammation by coupling selective protein degradation with alternative splicing. RNA splicing is significantly altered during senescence, some of which surprisingly depend on autophagy, including exon 5 skipping of the translation regulator EIF4H. Systematic translatome profiling indicates that this event is key to the translational bias toward inflammation in senescence. Autophagy promotes these changes by selectively degrading the splicing regulator splicing factor proline and glutamine rich (SFPQ) via the autophagy receptor NBR1. These autophagy-centric inflammatory controls appear to be conserved during human tissue aging and cancer. Our work highlights the role of autophagy in the on-demand functional remodeling of cellular proteomes as well as the crosstalk between autophagy, alternative splicing, and inflammatory translation.

Cellular senescence: from homeostasis to pathological implications and therapeutic strategies

Cellular aging is a multifactorial and intricately regulated physiological process with profound implications. The interaction between cellular senescence and cancer is complex and multifaceted, senescence can both promote and inhibit tumor progression through various mechanisms. M6A methylation modification regulates the aging process of cells and tissues by modulating senescence-related genes. In this review, we comprehensively discuss the characteristics of cellular senescence, the signaling pathways regulating senescence, the biomarkers of senescence, and the mechanisms of anti-senescence drugs. Notably, this review also delves into the complex interactions between senescence and cancer, emphasizing the dual role of the senescent microenvironment in tumor initiation, progression, and treatment. Finally, we thoroughly explore the function and mechanism of m6A methylation modification in cellular senescence, revealing its critical role in regulating gene expression and maintaining cellular homeostasis. In conclusion, this review provides a comprehensive perspective on the molecular mechanisms and biological significance of cellular senescence and offers new insights for the development of anti-senescence strategies.

Genomic instability and genetic heterogeneity in aging: insights from clonal hematopoiesis (CHIP), monoclonal gammopathy (MGUS), and monoclonal B-cell lymphocytosis (MBL)

Aging is a multifaceted process characterized by a gradual decline in physiological function and increased susceptibility to a range of chronic diseases. Among the molecular and cellular mechanisms driving aging, genomic instability is a fundamental hallmark, contributing to increased mutation load and genetic heterogeneity within cellular populations. This review explores the role of genomic instability and genetic heterogeneity in aging in the hematopoietic system, with a particular focus on clonal hematopoiesis of indeterminate potential (CHIP), monoclonal gammopathy of undetermined significance (MGUS), and monoclonal B-cell lymphocytosis (MBL) as biomarkers. CHIP involves the clonal expansion of hematopoietic stem cells with somatic mutations. In contrast, MGUS is characterized by the presence of clonal plasma cells producing monoclonal immunoglobulins, while MBL is characterized by clonal proliferation of B cells. These conditions are prevalent in the aging population and serve as measurable indicators of underlying genomic instability. Studying these entities offers valuable insights into the mechanisms by which somatic mutations accumulate and drive clonal evolution in the hematopoietic system, providing a deeper understanding of how aging impacts cellular and tissue homeostasis. In summary, the hematopoietic system serves as a powerful model for investigating the interplay between genomic instability and aging. Incorporating age-related hematological conditions into aging research, alongside other biomarkers such as epigenetic clocks, can enhance the precision and predictive power of biological age assessments. These biomarkers provide a comprehensive view of the aging process, facilitating the early detection of age-related diseases and hopefully enabling personalized healthcare strategies.

Accumulation of autophagosomes in aging human photoreceptor cell synapses

Autophagy is common in the aging retinal pigment epithelium (RPE). A dysfunctional autophagy in aged RPE is implicated in the pathogenesis of age-related macular degeneration. Aging human retina accompanies degenerative changes in photoreceptor mitochondria. It is not known how the damaged mitochondria are handled by photoreceptor cells with aging. This study examined donor human retinas (age: 56-94 years; N = 12) by transmission electron microscopy to find mitochondrial dynamics and status of autophagy in macular photoreceptor cells. Observations were compared between the relatively lower age (56-78 years) and aged retinas (80-94 years). Mitochondrial fusion was predominant in photoreceptor inner segments (ellipsoids), but rarely seen in the synaptic terminals. Also, fusion became widespread with progressive aging in ellipsoids (12% and 21% between rods and cones at tenth decade, respectively). More importantly, it was found that the photoreceptor synaptic mitochondria altered significantly with aging (swelling and loss of cristae), compared to those in ellipsoids that became dark and condensed. The damaged synaptic mitochondria were sequestered inside autophagosomes, whose frequency was higher in aged photoreceptors, being 34% in cone and 24% in rod terminals, at tenth decade. However, autolysosomes/residual bodies were rare, and thus the aged photoreceptor synaptic terminals harboured many autophagosomes, the possible reasons for which are discussed. Such age-related altered mitochondrial population and defective autophagy in synaptic terminals may influence photoreceptor survival in late aging.

Lycium barbarum glycopeptide ameliorates aging phenotypes and enhances cardiac metabolism by activating the PINK1/Parkin-mediated mitophagy pathway in D-galactose-induced mice

BACKGROUND

Aging is a complex biological process that disrupts tissue structure and impairs physiological function, which contributes to the development of age-related diseases such as cardiovascular disorders. However, effective treatment strategies are lacking.

OBJECTIVE

To investigate the geroprotective effects of Lycium barbarum glycopeptide (LbGp) and its potential mechanisms in a D-galactose-induced accelerated aging mouse model.

METHODS

Mice were subcutaneously injected with D-galactose (500 mg/kg/day) for 12 weeks to induce aging, while LbGp was orally administered (100 mg/kg/day) throughout the study. The geroprotective effects of LbGp were assessed by behavioral tests, cardiac echocardiography, pathohistological and transcriptomic analyses. Transmission electron microscopy was used to observe the ultrastructure of mitochondria. Mitochondrial stress assays and JC-1 fluorescent probe were conducted to evaluate mitochondrial function. Flow cytometer and western blot were performed to assess mitophagy flux.

RESULTS

LbGp treatment improved the aging phenotypes of D-galactose-induced mice, with a pronounced enhancement in cardiac function compared to neurocognitive and skeletal muscle functions. Transcriptome analysis indicated that LbGp ameliorated energy metabolism in the heart. Mitochondrial assays revealed LbGp improved mitochondrial function and preserved structural integrity of the mitochondrial inner membrane. LbGp attenuated mitochondrial fission and restored impaired PINK1/Parkin-mediated mitophagy pathway caused by D-galactose in cardiomyocytes.

CONCLUSION

LbGp can ameliorate aging phenotypes and enhance cardiac metabolism by activating the PINK1/Parkin-mediated mitophagy pathway in D-galactose-induced mice. These findings underscore its potential as a therapeutic agent for aging and aging-related cardiovascular diseases.

Elevated N-glycosylated cathepsin L impairs oocyte function and contributes to oocyte senescence during reproductive aging

Age-related declines in oocyte quality and ovarian function are pivotal contributors to female subfertility in clinical settings. Yet, the mechanisms driving ovarian aging and oocyte senescence remain inadequately understood. The present study evaluated the alterations in N-glycoproteins associated with ovarian aging and noted a pronounced elevation in N221 glycopeptides of cathepsin L (Ctsl) in the ovaries of reproductive-aged mice (8-9 months and 11-12 months) compared to younger counterparts (6-8 weeks). Subsequent analysis examined the involvement of Ctsl in oocyte aging and demonstrated a significant elevation in Ctsl levels in aged oocytes. Further, it was revealed that the overexpression of Ctsl in young oocytes substantially diminished their quality, while oocytes expressing an N221-glycosylation mutant of Ctsl did not suffer similar quality degradation. This finding implies that the N221 glycosylation of Ctsl is pivotal in modulating its effect on oocyte health. The introduction of a Ctsl inhibitor into the culture medium restored oocyte quality in aged oocytes by enhancing mitochondrial function, reducing accumulated reactive oxygen species (ROS), lowering apoptosis, and recovering lysosome capacity. Furthermore, the targeted downregulation of Ctsl using siRNA microinjection in aged oocytes enhanced fertilization capability and blastocyst formation, affirming the role of Ctsl knockdown in fostering oocyte quality and embryonic developmental potential. In conclusion, these findings underscore the detrimental effects of high expression of N-glycosylated Ctsl on oocyte quality and its contribution to oocyte senescence, highlighting it as a potential therapeutic target to delay ovarian aging and enhance oocyte viability.

Aging, cancer, and autophagy: connections and therapeutic perspectives

Aging and cancer are intricately linked through shared molecular processes that influence both the onset of malignancy and the progression of age-related decline. As organisms age, cellular stress, genomic instability, and an accumulation of senescent cells create a pro-inflammatory environment conducive to cancer development. Autophagy, a cellular process responsible for degrading and recycling damaged components, plays a pivotal role in this relationship. While autophagy acts as a tumor-suppressive mechanism by preventing the accumulation of damaged organelles and proteins, cancer cells often exploit it to survive under conditions of metabolic stress and treatment resistance. The interplay between aging, cancer, and autophagy reveals key insights into tumorigenesis, cellular senescence, and proteostasis dysfunction. This review explores the molecular connections between these processes, emphasizing the potential for autophagy-targeted therapies as strategies that could be further explored in both aging and cancer treatment. Understanding the dual roles of autophagy in suppressing and promoting cancer offers promising avenues for therapeutic interventions aimed at improving outcomes for elderly cancer patients while addressing age-related deterioration.

Caloric restriction and its mimetics in heart failure with preserved ejection fraction: mechanisms and therapeutic potential

The global increase in human life expectancy, coupled with an unprecedented rise in the prevalence of obesity, has led to a growing clinical and socioeconomic burden of heart failure with preserved ejection fraction (HFpEF). Mechanistically, the molecular and cellular hallmarks of aging are omnipresent in HFpEF and are further exacerbated by obesity and associated metabolic diseases. Conversely, weight loss strategies, particularly caloric restriction, have shown promise in improving health status in patients with HFpEF and are considered the gold standard for promoting longevity and healthspan (disease-free lifetime) in model organisms. In this review, we implicate fundamental mechanisms of aging in driving HFpEF and elucidate how caloric restriction mitigates the disease progression. Furthermore, we discuss the potential for pharmacologically mimicking the beneficial effects of caloric restriction in HFpEF using clinically approved and emerging caloric restriction mimetics. We surmise that these compounds could offer novel therapeutic avenues for HFpEF and alleviate the challenges associated with the implementation of caloric restriction and other lifestyle modifications to reduce the burden of HFpEF at a population level.

V-ATPase Disassembly at the Yeast Lysosome-Like Vacuole Is a Phenotypic Driver of Lysosome Dysfunction in Replicative Aging

Declines in lysosomal acidification and function with aging are observed in organisms ranging from yeast to humans. V-ATPases play a central role in organelle acidification, and V-ATPase activity is regulated by reversible disassembly in many different settings. Using the yeast Saccharomyces cerevisiae as a replicative aging model, we demonstrate that V-ATPases disassemble into their V1 and V0 subcomplexes in aging cells, with release of V1 subunit C (Vma5) from the lysosome-like vacuole into the cytosol. Disassembly is observed after > 5 cell divisions and results in overall vacuole alkalinization. Caloric restriction, an established mechanism for reversing many age-related outcomes, prevents V-ATPase disassembly in older cells and preserves vacuolar pH homeostasis. Reversible disassembly is controlled in part by the activity of two opposing and conserved factors: the Regulator of Acidification of Vacuoles and Endosomes (RAVE) complex and Oxr1. The RAVE complex promotes V-ATPase assembly and a rav1∆ mutant shortens replicative lifespan; Oxr1 promotes disassembly and an oxr1∆ mutation extends the lifespan. Importantly, the level of Rav2, a subunit of the RAVE complex, declines in aged cells, and Rav2 overexpression delays V-ATPase disassembly with age. These data indicate that reduced V-ATPase assembly contributes to the loss of lysosomal acidification with age, which affects replicative lifespan.

Vinpocetine alleviates the abdominal aortic aneurysm progression via VSMCs SIRT1-p21 signaling pathway

Abdominal aortic aneurysm (AAA) is a degenerative disease that caused mortality in people aged >65. Senescence plays a critical role in AAA pathogenesis. Advances in AAA repair techniques have occurred, but a remaining priority is therapies to limit AAA growth and rupture. Our Previous study found cyclic nucleotide phosphodiesterase 1C (PDE1C) exacerbate AAA through aggravate vascular smooth muscle cells (VSMCs) senescence by downregulating Sirtuin1 (SIRT1) expression and activity. Vinpocetine as a selective inhibitor of PDE1 and a clinical medication for cerebral vasodilation, it is unclear whether vinpocetine can rely on SIRT1 to alleviate AAA. This study showed that pre-treatment with vinpocetine remarkably prevented aneurysmal dilation and reduced aortic rupture in elastase-induced AAA mice. In addition, the elastin degradation, MMP (matrix metalloproteinase) activity, macrophage infiltration, ROS production, collagen fibers remodeling, and VSMCs senescence were decreased in AAA treated with vinpocetine. While these effects were unable to exert in VSMCs-specific SIRT1 knockout AAA mice. Accordingly, we revealed that vinpocetine suppressed migration, proliferation, and senescence in VSMCs. Moreover, vinpocetine reduced SIRT1 degradation by inhibiting lysosome-mediated autophagy. In conclusion, this study indicated that vinpocetine may be as a potential drug for therapy AAA through alleviate VSMCs senescence via the SIRT1-dependent pathway.

Enhancement of Bone Repair in Diabetic Rats with Metformin-Modified Silicified Collagen Scaffolds

Regenerating bone defects in diabetic rats presents a significant challenge due to the detrimental effects of reactive oxygen species and impaired autophagy on bone healing. To address these issues, a metformin-modified biomimetic silicified collagen scaffold is developed utilizing the principles of biomimetic silicification. In vitro and in vivo experiments demonstrated that the scaffold enhanced bone tissue regeneration within the diabetic microenvironment through the release of dual bio-factors. Further analysis reveals a potential therapeutic mechanism whereby these dual bio-factors synergistically promoted osteogenesis in areas of diabetic bone defects by improving mitochondrial autophagy and maintaining redox balance. The present study provides critical insights into the advancement of tissue engineering strategies aimed at bone regeneration in diabetic patients. The study also sheds light on the underlying biological mechanisms.

Role of Quercetin in Diabetic Cardiomyopathy

Diabetic cardiomyopathy is a significant and severe complication of diabetes that affects a large portion of the global population, with its prevalence continuing to rise. Secondary metabolites, including quercetin, have shown promising effects in mitigating the progression of diabetic cardiomyopathy by targeting multiple pathological mechanisms, including impaired insulin signaling, glucotoxicity, lipotoxicity, oxidative stress, inflammation, fibrosis, apoptosis, autophagy, mitochondrial dysfunction, cardiac stiffness, and disrupted calcium handling. Addressing these mechanisms is crucial to prevent left ventricular diastolic and systolic dysfunction in advanced stages of diabetic heart disease. Scientific evidence has highlighted the cardioprotective properties of quercetin at both the myocardial and cellular/molecular levels in diabetic models. Therefore, this review aims to present a comprehensive overview of the proposed mechanisms underlying quercetin's beneficial effects, providing valuable insights that could inform future drug discovery efforts specific to diabetic cardiomyopathy.

Understanding the impact of ER stress on lung physiology

Human lungs consist of a distinctive array of cell types, which are subjected to persistent challenges from chemical, mechanical, biological, immunological, and xenobiotic stress throughout life. The disruption of endoplasmic reticulum (ER) homeostatic function, triggered by various factors, can induce ER stress. To overcome the elevated ER stress, an adaptive mechanism known as the unfolded protein response (UPR) is activated in cells. However, persistent ER stress and maladaptive UPR can lead to defects in proteostasis at the cellular level and are typical features of the lung aging. The aging lung and associated lung diseases exhibit signs of ER stress-related disruption in cellular homeostasis. Dysfunction resulting from ER stress and maladaptive UPR can compromise various cellular and molecular processes associated with aging. Hence, comprehending the mechanisms of ER stress and UPR components implicated in aging and associated lung diseases could enable to develop appropriate therapeutic strategies for the vulnerable population.

V-ATPase Disassembly at the Yeast Lysosome-Like Vacuole Is a Phenotypic Driver of Lysosome Dysfunction in Replicative Aging

Declines in lysosomal acidification and function with aging are observed in organisms ranging from yeast to humans. V-ATPases play a central role in organelle acidification and V-ATPase activity is regulated by reversible disassembly in many different settings. Using the yeast Saccharomyces cerevisiae as a replicative aging model, we demonstrate that V-ATPases disassemble into their V1 and V0 subcomplexes in aging cells, with release of V1 subunit C (Vma5) from the lysosome-like vacuole into the cytosol. Disassembly is observed after ≥5 cell divisions and results in overall vacuole alkalinization. Caloric restriction, an established mechanism for reversing many age-related outcomes, prevents V-ATPase disassembly in older cells and preserves vacuolar pH homeostasis. Reversible disassembly is controlled in part by the activity of two opposing and conserved factors, the RAVE complex and Oxr1. The RAVE complex promotes V-ATPase assembly and a rav1Δ mutant shortens replicative lifespan; Oxr1 promotes disassembly and an oxr1Δ mutation extends lifespan. Importantly, the level of Rav2, a subunit of the RAVE complex, declines in aged cells, and Rav2 overexpression delays V-ATPase disassembly with age. These data indicate that reduced V-ATPase assembly contributes to the loss of lysosome acidification with age, which affects replicative lifespan.

Chaperone-mediated autophagy as a modulator of aging and longevity

Chaperone-mediated autophagy (CMA) is the lysosomal degradation of individually selected proteins, independent of vesicle fusion. CMA is a central part of the proteostasis network in vertebrate cells. However, CMA is also a negative regulator of anabolism, and it degrades enzymes required for glycolysis, de novo lipogenesis, and translation at the cytoplasmic ribosome. Recently, CMA has gained attention as a possible modulator of rodent aging. Two mechanistic models have been proposed to explain the relationship between CMA and aging in mice. Both of these models are backed by experimental data, and they are not mutually exclusionary. Model 1, the "Longevity Model," states that lifespan-extending interventions that decrease signaling through the INS/IGF1 signaling axis also increase CMA, which degrades (and thereby reduces the abundance of) several proteins that negatively regulate vertebrate lifespan, such as MYC, NLRP3, ACLY, and ACSS2. Therefore, enhanced CMA, in early and midlife, is hypothesized to slow the aging process. Model 2, the "Aging Model," states that changes in lysosomal membrane dynamics with age lead to age-related losses in the essential CMA component LAMP2A, which in turn reduces CMA, contributes to age-related proteostasis collapse, and leads to overaccumulation of proteins that contribute to age-related diseases, such as Alzheimer's disease, Parkinson's disease, cancer, atherosclerosis, and sterile inflammation. The objective of this review paper is to comprehensively describe the data in support of both of these explanatory models, and to discuss the strengths and limitations of each.

Aging Lung: Molecular Drivers and Impact on Respiratory Diseases-A Narrative Clinical Review

The aging process significantly impacts lung physiology and is a major risk factor for chronic respiratory diseases, including chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), asthma, and non-IPF interstitial lung fibrosis. This narrative clinical review explores the molecular and biochemical hallmarks of aging, such as oxidative stress, telomere attrition, genomic instability, epigenetic modifications, proteostasis loss, and impaired macroautophagy, and their roles in lung senescence. Central to this process are senescent cells, which, through the senescence-associated secretory phenotype (SASP), contribute to chronic inflammation and tissue dysfunction. The review highlights parallels between lung aging and pathophysiological changes in respiratory diseases, emphasizing the role of cellular senescence in disease onset and progression. Despite promising research into modulating aging pathways with interventions like caloric restriction, mTOR inhibitors, and SIRT1 activators, clinical evidence for efficacy in reversing or preventing age-related lung diseases remains limited. Understanding the interplay between aging-related mechanisms and environmental factors, such as smoking and pollution, is critical for developing targeted therapies. This review underscores the need for future studies focusing on therapeutic strategies to mitigate aging's detrimental effects on lung health and improve outcomes for patients with chronic respiratory conditions.

Programmed cell death: molecular mechanisms, biological functions, diseases, and therapeutic targets

Programmed cell death represents a precisely regulated and active cellular demise, governed by a complex network of specific genes and proteins. The identification of multiple forms of programmed cell death has significantly advanced the understanding of its intricate mechanisms, as demonstrated in recent studies. A thorough grasp of these processes is essential across various biological disciplines and in the study of diseases. Nonetheless, despite notable progress, the exploration of the relationship between programmed cell death and disease, as well as its clinical application, are still in a nascent stage. Therefore, further exploration of programmed cell death and the development of corresponding therapeutic methods and strategies holds substantial potential. Our review provides a detailed examination of the primary mechanisms behind apoptosis, autophagy, necroptosis, pyroptosis, and ferroptosis. Following this, the discussion delves into biological functions and diseases associated dysregulated programmed cell death. Finally, we highlight existing and potential therapeutic targets and strategies focused on cancers and neurodegenerative diseases. This review aims to summarize the latest insights on programmed cell death from mechanisms to diseases and provides a more reliable approach for clinical transformation.

Protective effect of zinc against A2E-induced toxicity in ARPE-19 cells: Possible involvement of lysosomal acidification

A key pathogenic mechanism of dry age-related macular degeneration (AMD) is lysosomal dysfunction in retinal pigment epithelium (RPE) cells, which results in the accumulation of lipofuscins such as A2E (N-retinylidene-N-retinylethanolamine) that further compromises lysosomal function. This vicious cycle leads to cell death and poor visual acuity. Here, we established an in vitro model of AMD by treating a human RPE cell line (ARPE-19) with A2E and examined whether raising zinc levels confers protective effects against lysosomal dysfunction and cytotoxicity. MTT assay showed that A2E induced apoptosis in ARPE-19 cells. pHrodo™ Red fluorescence staining showed that lysosomal pH increased in A2E-treated ARPE-19 cells. Treatment with a zinc ionophore (clioquinol) reduced A2E accumulation, restored lysosomal pH to the acidic range, and reduced A2E-induced cell death, all of which were reversed by the addition of a zinc chelator (TPEN). Consistent with the in vitro results, subretinal injections of A2E in mouse eyes resulted in the death of RPE cells as well as lysosomal dysfunction, all of which were reversed by co-treatment with clioquinol. Our results suggest that restoring the levels of intracellular zinc, especially in lysosomes, would be helpful in mitigating A2E-induced cytotoxic changes including lysosomal dysfunction in RPE cells in the pathogenesis of AMD.

Nonlinear dynamics of multi-omics profiles during human aging

Aging is a complex process associated with nearly all diseases. Understanding the molecular changes underlying aging and identifying therapeutic targets for aging-related diseases are crucial for increasing healthspan. Although many studies have explored linear changes during aging, the prevalence of aging-related diseases and mortality risk accelerates after specific time points, indicating the importance of studying nonlinear molecular changes. In this study, we performed comprehensive multi-omics profiling on a longitudinal human cohort of 108 participants, aged between 25 years and 75 years. The participants resided in California, United States, and were tracked for a median period of 1.7 years, with a maximum follow-up duration of 6.8 years. The analysis revealed consistent nonlinear patterns in molecular markers of aging, with substantial dysregulation occurring at two major periods occurring at approximately 44 years and 60 years of chronological age. Distinct molecules and functional pathways associated with these periods were also identified, such as immune regulation and carbohydrate metabolism that shifted during the 60-year transition and cardiovascular disease, lipid and alcohol metabolism changes at the 40-year transition. Overall, this research demonstrates that functions and risks of aging-related diseases change nonlinearly across the human lifespan and provides insights into the molecular and biological pathways involved in these changes.

Targeting lysosomal quality control as a therapeutic strategy against aging and diseases

Previously, lysosomes were primarily referred to as the digestive organelles and recycling centers within cells. Recent discoveries have expanded the lysosomal functional scope and revealed their critical roles in nutrient sensing, epigenetic regulation, plasma membrane repair, lipid transport, ion homeostasis, and cellular stress response. Lysosomal dysfunction is also found to be associated with aging and several diseases. Therefore, function of macroautophagy, a lysosome-dependent intracellular degradation system, has been identified as one of the updated twelve hallmarks of aging. In this review, we begin by introducing the concept of lysosomal quality control (LQC), which is a cellular machinery that maintains the number, morphology, and function of lysosomes through different processes such as lysosomal biogenesis, reformation, fission, fusion, turnover, lysophagy, exocytosis, and membrane permeabilization and repair. Next, we summarize the results from studies reporting the association between LQC dysregulation and aging/various disorders. Subsequently, we explore the emerging therapeutic strategies that target distinct aspects of LQC for treating diseases and combatting aging. Lastly, we underscore the existing knowledge gap and propose potential avenues for future research.

Chloramphenicol alleviates 5-fluorouracil-induced cellular senescence through activation of autophagy

5-Fluorouracil (5-FU) is a first-line treatment for colorectal cancer, but side effects such as severe diarrhea are common in clinical use and have been linked to its induction of normal cell senescence. Chloramphenicol (CAP) is an antibiotic commonly used to treat typhoid or anaerobic infections, but its senescence-related aspects have not been thoroughly investigated. Here, we used 5-FU to induce senescence in human umbilical vein endothelial cells (HUVECs) and investigated the relationship between CAP and cellular senescence at the cellular level. In a model of cellular senescence induced by 5-FU treatment, we discovered that CAP treatment reversed the rise in the percentage of senescence-associated galactosidase (SA-β-gal)-positive cells and decreased the expression of senescence-associated proteins (p16), senescence-associated genes (p21), and senescence-associated secretory phenotypes (SASPs: IL-6, TNF-α). In addition, CAP subsequently restored the autophagic process inhibited by 5-FU and upregulated the levels of autophagy-related proteins. Mechanistically, we found that CAP restored autophagic flux by inhibiting the mTOR pathway, which in turn alleviated FU-induced cellular senescence. Our findings suggest that CAP may help prevent cellular senescence and restore autophagy, opening up new possibilities and approaches for the clinical management of colorectal cancer.

Enhancing Cellular Homeostasis: Targeted Botanical Compounds Boost Cellular Health Functions in Normal and Premature Aging Fibroblasts

The human skin, the body's largest organ, undergoes continuous renewal but is significantly impacted by aging, which impairs its function and leads to visible changes. This study aimed to identify botanical compounds that mimic the anti-aging effects of baricitinib, a known JAK1/2 inhibitor. Through in silico screening of a botanical compound library, 14 potential candidates were identified, and 7 were further analyzed for their effects on cellular aging. The compounds were tested on both normal aged fibroblasts and premature aging fibroblasts derived from patients with Hutchinson-Gilford Progeria Syndrome (HGPS). Results showed that these botanical compounds effectively inhibited the JAK/STAT pathway, reduced the levels of phosphorylated STAT1 and STAT3, and ameliorated phenotypic changes associated with cellular aging. Treatments improved cell proliferation, reduced senescence markers, and enhanced autophagy without inducing cytotoxicity. Compounds, such as Resveratrol, Bisdemethoxycurcumin, Pinosylvin, Methyl P-Hydroxycinnamate, cis-Pterostilbene, and (+)-Gallocatechin, demonstrated significant improvements in both control and HGPS fibroblasts. These findings suggest that these botanical compounds have the potential to mitigate age-related cellular alterations, offering promising strategies for anti-aging therapies, particularly for skin health. Further in vivo studies are warranted to validate these results and explore their therapeutic applications.

From Reactive to Proactive - The Future Life Design to Promote Health and Extend the Human Lifespan

Disease treatment and prevention have improved the human lifespan. Current studies on aging, such as the biological clock and senolytic drugs have focused on the medical treatments of various disorders and health maintenance. However, to efficiently extend the human lifespan to its theoretical maximum, medicine can take a further proactive approach and identify the inapparent disorders that affect the gestation, body growth, and reproductive stages of the so-called "healthy" population. The goal is to upgrade the standard health status to a new level by targeting the inapparent disorders. Thus, future research can shift from reaction, response, and prevention to proactive, quality promotion and vigor prolonging; from single disease-oriented to multiple dimension protocol for a healthy body; from treatment of symptom onset to keep away from disorders; and from the healthy aging management to a healthy promotion design beginning at the birth.