Aging-related diseases, which are associated with the senescence of endothelial progenitor cells (EPCs), are consistently accompanied by elevated levels of circulating trimethylamine-N-oxide (TMAO), a marker predictive of poor prognosis. Lycopene (Lyc) deficiency has been demonstrated to be linked to these age-related diseases. The AMPK/SIRT1 pathway plays a pivotal role in cellular senescence. In this study, we hypothesize that lycopene could mitigate TMAO-induced EPCs senescence, with involvement of the AMPK/SIRT1 pathway. EPCs were subjected to treatment with TMAO, Lyc, small interfering RNA targeting AMP-activated protein kinase (siAMPK), or sirtin-1 (siSIRT1). The biological functions of EPCs were evaluated through, CCK-8, transwell and tube formation assays, while their senescence was assessed via SA-β-gal activity assay and Western blotting. ROS generation was measured using dichlorodihydrofluorescein diacetate staining. TMAO-induced suppression of EPCs' functionality was alleviated by Lyc, but this effect was reversed by siAMPK and siSIRT1. TMAO increased SA-β-gal-positive cell number and ROS production, while reducing the expression of AMPK and SIRT1. These effects were attenuated by Lyc. However, the protective effects were diminished by siAMPK and siSIRT1. In conclusion, Lyc ameliorates TMAO-induced EPCs senescence through the AMPK/SIRT1 pathway.

The senescence-associated secretory phenotype (SASP) is closely linked to aging by promoting inflammation and tissue degradation. Sensing SASP is crucial for early detection of and intervention in age-related diseases to enhance therapeutic outcomes. Herein, SASP-selective sensors (transforming growth factor [TGF]-β1 and interleukin [IL]-6 probes) were designed by utilizing TGF-β1/IL-6 aptamers-functionalized copper-immobilized polymer dots that promoted specific binding between TGF-β1/IL-6 aptamers on the probe surface with aging factors (TGF-β1 and IL-6).

The selective binding was reflected by changes in the conductivity of the probes. The TGF-β1 and IL-6 probes showed high sensitivity towards TGF-β1 and IL-6, with limits of detection of 193.09 pg/mL for the TGF-β1 (R2 = 0.9989) and 16.49 pg/mL (R2 = 0.9998) for IL-6 probes. In vitro study using senescent cells confirmed that the probes could selectively detect TGF-β1 and IL-6, indicated by increased resistance with longer incubation times (TGF-β172h = 2.775 MΩ, IL-672h = 2.401 MΩ). Furthermore, the TGF-β1 and IL-6 probes exhibited excellent detection performance in in vivo samples from aging mouse models when monitoring the levels of TGF-β1 and IL-6 at different times after lenti soup injection and at different mouse ages (6-20 months). Additionally, the electrical signals generated during sensing can be displayed on a smartphone via a wireless sensing system.

TGF-β1 and IL-6 probes provide a sensitive, specific and accessible diagnostic platform for senescence aging factors monitoring, which are expected to be an essential tool that transforms the analysis of aging and age-related diseases.

Cellular senescence is a fundamental yet complex defense mechanism that restricts excessive proliferation, maintains cellular homeostasis under various stress conditions-such as oncogenic activation and inflammation-and serves as a dynamic stress response program involved in development, aging, and immunity. Its reversibility depends on essential maintenance components. Cellular senescence is a "double-edged sword": on one hand, it limits the malignant proliferation of damaged cells, thereby preventing tumor development. However, by retaining secretory functions, senescent cells can also induce persistent changes in the microenvironment and disrupt homeostasis, leading to tissue inflammation, fibrosis, and carcinogenesis. Senescence plays a critical role in the pathogenesis of various chronic liver diseases, including chronic viral hepatitis, liver fibrosis, and hepatocellular carcinoma. It exerts a dual influence by facilitating immune evasion and inflammation in chronic viral hepatitis, modulating hepatic stellate cell activity in fibrosis, and reshaping the tumor microenvironment to accelerate hepatocarcinogenesis. This article reviews the characteristics of cellular senescence and its role in the pathogenesis of these chronic liver diseases while exploring potential treatment and prevention strategies. The aim is to provide a comprehensive reference for future clinical and research investigations into chronic liver disease.

Cellular senescence spreads systemically through blood circulation, but its mechanisms remain unclear. High mobility group box 1 (HMGB1), a multifunctional senescence-associated secretory phenotype (SASP) factor, exists in various redox states. Here, we investigate the role of redox-sensitive HMGB1 (ReHMGB1) in driving paracrine and systemic senescence.

We applied the paracrine senescence cultured model to evaluate the effect of ReHMGB1 on cellular senescence. Each redox state of HMGB1 was treated extracellularly to assess systemic senescence both in vitro and in vivo. Senescence was determined by SA-β-gal & EdU staining, p16INK4a and p21 expression, RT-qPCR, and Western blot methods. Bulk RNA sequencing was performed to investigate ReHMGB1-driven transcriptional changes and underlying pathways. Cytokine arrays characterized SASP profiles from ReHMGB1-treated cells. In vivo, young mice were administered ReHMGB1 systemically to induce senescence across multiple tissues. A muscle injury model in middle-aged mice was used to assess the therapeutic efficacy of HMGB1 blockade.

Extracellular ReHMGB1, but not its oxidized form, robustly induced senescence-like phenotypes across multiple cell types and tissues. Transcriptomic analysis revealed activation of RAGE-mediated JAK/STAT and NF-κB pathways, driving SASP expression and cell cycle arrest. Cytokine profiling confirmed paracrine senescence features induced by ReHMGB1. ReHMGB1 administration elevated senescence markers in vivo, while HMGB1 inhibition reduced senescence, attenuated systemic inflammation, and enhanced muscle regeneration.

ReHMGB1 is a redox-dependent pro-geronic factor driving systemic senescence. Targeting extracellular HMGB1 may offer therapeutic potential for preventing aging-related pathologies.

As the elderly population grows, the number of patients with metabolic bone diseases such as osteoporosis has increased sharply, posing a significant threat to public health and social economics. Although pharmacological therapies for osteoporosis demonstrate therapeutic benefits, their prolonged use is associated with varying degrees of adverse effects. As a non-pharmacological intervention, exercise is widely recognized for its cost-effectiveness, safety, and lack of toxic side effects, making it a recommended treatment for osteoporosis prevention and management. Previous studies have demonstrated that exercise can improve metabolic bone diseases by modulating the Senescent Associated Secretory Phenotype (SASP). However, the mechanisms through which exercise influences SASP remain unclear. Therefore, this review aims to summarize the effects of exercise on SASP and elucidate the specific mechanisms by which exercise regulates SASP to alleviate osteoporosis, providing a theoretical basis for osteoporosis through exercise and developing targeted therapies.

The tumor-immune microenvironment (TIME) plays a critical role in tumor development and metastasis, as it influences the evolution of tumor cells and fosters an immunosuppressive state by intervening the metabolic reprogramming of infiltrating immune cells. Aging and diet significantly impact the metabolic reprogramming of the TIME, contributing to cancer progression and immune evasion. With aging, immune cell function declines, leading to a proinflammatory state and metabolic alterations such as increased oxidative stress and mitochondrial dysfunction, which compromise antitumor immunity. Similarly, dietary factors, particularly high-fat and high-sugar diets, promote metabolic shifts, creating a permissive TIME by fostering tumor-supportive immune cell phenotypes while impairing the tumoricidal activity of immune cells. In contrast, dietary restrictions have been shown to restore immune function by modulating metabolism and enhancing antitumor immune responses. Here, we discuss the intricate interplay between aging, diet, and metabolic reprogramming in shaping the TIME, with a particular focus on T cells, and highlight therapeutic strategies targeting these pathways to empower antitumor immunity.

Partial or transient cellular reprogramming is defined by the limited induction of pluripotency factors without full dedifferentiation of cells to a pluripotent state. Comparing in vitro and in vivo mouse studies, and in vitro studies in humans, supported by visualizations of data interconnections, we show consistent patterns in how such reprogramming modulates key biological processes. Generally, partial reprogramming drives dynamic chromatin remodelling, involving histone modifications that regulate accessibility and facilitate pluripotency gene activation while silencing somatic identity. These changes are accompanied by modifications in stress response programs, such as inflammation, autophagy, and cellular senescence, as well as improved mitochondrial activity and dysregulation of extracellular matrix pathways. We also underscore the challenges in evaluating complex processes like aging and cellular senescence, given the variability in biomarkers used across studies. Overall, we highlight biological processes consistently influenced by reprogramming while noting that some effects are context-dependent, varying according to cell type, species, sex, recovery time, and the reprogramming method employed. These insights inform future research and potential therapeutic applications in aging and regenerative medicine.

In humans, the release factor eRF3a exists in several forms that differ in the length of the polyglycine tract (7, 10, 11 or 12 glycines) in its N-terminal domain. For the 12-Gly eRF3a, an association with cancer risk and a decreased affinity for the cytoplasmic poly (A) binding protein have already been established. In this work, HCT116 colon cancer cells were treated with low doses of doxorubicin, which is known to induce senescence in these cells with high efficiency. The expression of p21 and p53 (senescence marker proteins) as well as lysosomal β-galactosidase activity were reduced when 12-Gly-eRF3a was overexpressed or eRF3a was depleted in cells. If low activity of mTORC1 pathway might be responsible for reduced senescence onset after eRF3a depletion, its activity is maintained in cells overexpressing 12-Gly-eRF3a. In both cases, a defect in termination efficiency could be involved.

Long noncoding RNAs (lncRNAs) have emerged as critical regulators of vascular senescence and microvascular remodeling, processes that significantly contribute to the development of age-related diseases in organs such as the kidneys, heart, and lungs. Through mechanisms like chromatin remodeling, transcriptional regulation, and posttranscriptional modifications, lncRNAs modulate gene expression, thereby influencing cellular processes such as apoptosis, inflammation, fibrosis, and angiogenesis. In chronic kidney disease, cardiovascular disease, and pulmonary disorders, lncRNAs play a central role in promoting vascular dysfunction, endothelial cell aging, and fibrosis. This review focuses on how lncRNAs contribute to endothelial dysfunction, fibrosis, and vascular aging, emphasizing their roles in disease progression within the kidneys, heart, and lungs, where lncRNA-mediated vascular changes play a significant role in disease progression. Understanding the interactions between lncRNAs, vascular senescence, and microvascular remodeling offers promising avenues for developing targeted therapeutic strategies to mitigate the impact of aging on vascular health.

In human beings heterogenous, pervasive and lethal malignancies of different parts of the gastrointestinal (GI) tract viz., tumours of the oesophagus, stomach, small intestine, colon, and rectum, represent gastrointestinal malignancies. Primary treatment modality for gastric cancer includes chemotherapy, surgical interventions, radiotherapy, monoclonal antibodies and inhibitors of angiogenesis. However, there is a need to improve upon the existing treatment modality due to associated adverse events and the development of resistance towards treatment. Additionally, age has been found to contribute to increasing the incidence of tumours due to immunosenescence-associated immunosuppression. Immunosenescence is the natural process of ageing, wherein immune cells as well as organs begin to deteriorate resulting in a dysfunctional or malfunctioning immune system. Accretion of senescent cells in immunosenescence results in the creation of a persistent inflammatory environment or inflammaging, marked with elevated expression of pro-inflammatory and immunosuppressive cytokines and chemokines. Perturbation in the T-cell pools and persistent stimulation by the antigens facilitate premature senility of the immune cells, and senile immune cells exacerbate inflammaging conditions and the inefficiency of the immune system to identify the tumour antigen. Collectively, these conditions contribute positively towards tumour generation, growth and eventually proliferation. Thus, activating the immune cells to distinguish the tumour cells from normal cells and invade them seems to be a logical strategy for the treatment of cancer. Consequently, various approaches to immunotherapy, viz., programmed death ligand-1 (PD-1) inhibitors, Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors etc are being extensively evaluated for their efficiency in gastric cancer. In fact, PD-1 inhibitors have been sanctioned as late late-line therapy modality for gastric cancer. The present review will focus on deciphering the link between the immune system and gastric cancer, and the alterations in the immune system that incur during the development of gastrointestinal malignancies. Also, the mechanism of evasion by tumour cells and immune checkpoints involved along with different approaches of immunotherapy being evaluated in different clinical trials will be discussed.

Obesity and type 2 diabetes mellitus (T2DM) are metabolic diseases at epidemic proportions. The economic burden for these diseases is at an all-time high, and as such, there is an urgent need for advancements in identifying targets for treating these complex disorders. The extracellular matrix (ECM), comprising collagen, fibronectin, laminin, elastin, and proteoglycan, surrounds skeletal muscles and plays a critical role in maintaining tissue homeostasis by providing structural support and facilitating cell-to-cell communication. Disruption of the ECM signaling results in changes to its micro/macroenvironment, thereby modifying tissue homeostasis. Skeletal muscle ECM remodeling has been shown to be associated with insulin resistance, an underlying feature of obesity and T2DM. This narrative review explores the critical components of skeletal muscle ECM and its accumulation and remodeling in metabolic diseases. In addition, we discuss potential treatments to mitigate the effects of ECM remodeling in skeletal muscle. We conclude that targeting ECM remodeling in skeletal muscle represents a promising yet underexplored therapeutic avenue in the management of metabolic disorders.

Resistance to radiotherapy (RT) presents a significant clinical challenge in management of cancer. Recent evidence points to specific mechanisms of resistance within the tumor microenvironment (TME), which we aim to discuss, with the aim of overcoming the clinical challenge.

We performed the narrative review using PubMed and Web of Science databases to identify studies that reported the regulative network and treatments of RT resistance from TME perspectives.

RT significantly changes the immune TME of cancers, which is closely appearing to play a key role in RT resistance (RTR) by modulating immune cell infiltration and function. Various phenotypes are involved in the development of RTR, such as autophagy, senescence, oxidative stress, cell polarization, ceramide metabolism, and angiogenesis in the TME. Key genes and pathways are also implicated in RTR, including immune and inflammatory cytokines, TGF-β, P53, the NF-κB pathway, the cGAS/STING pathway, the ERK and AKT pathway, and the STAT pathway. Based on the mechanism of RTR in the TME, many proposed routes to overcome RTR, several specifically target the TME including targeting fibroblast activation protein, exosomes management, nanomedicine, and immunotherapy. Many challenges in RT resistance still need to be further explored with emerging investigative methods, such as artificial intelligence, genetic technologies, and bioengineering.

The complex interactions between RT and TME significantly affect the efficiency of RT. Novel approaches to overcome this clinical difficulty are promising, which needs future work to further explore and identify better treatment strategies.

Senescence is a complex cellular state that can be considered as a stress response phenotype. A decade ago, we suggested the intricate connections between unfolded protein response (UPR) signaling and the development of the senescent phenotype. Over the past ten years, significant advances have been made in understanding the multifaceted role of the UPR in regulating cellular senescence, highlighting its contribution to biological processes such as oxidative stress and autophagy. In this updated review, we expand these interconnections with the benefit of new insights, and we suggest that targeting specific components of the UPR could provide novel therapeutic strategies to mitigate the deleterious effects of senescence, with significant implications for age-related pathologies and geroscience.

The neurodegenerative processes driving the build-up of disability in progressive multiple sclerosis (P-MS) have not been fully elucidated. Recent data link cellular senescence (CS) to neurodegeneration. We investigated for evidence of CS in P-MS and sought to determine its pattern.

We used 53BP1, p16, and lipofuscin as markers of CS in white matter lesions (WMLs), normal appearing white matter (NAWM), normal appearing cortical gray matter (NAGM), control white matter (CWM), and control gray matter (CGM) on autopsy material from patient with P-MS and healthy controls. Senescence-associated secretory phenotype (SASP) factors were quantified in cerebrospinal fluid (CSF).

P16+ cell counts were significantly increased in WMLs and GMLs, compared with NAWM, CWM, NAGM, and CGM and lipofuscin+ cells were significantly increased in WMLs, compared with NAWM and CWM, indicating more abundant CS in demyelinated lesions. The 53BP1+ cells in WMLs were significantly increased compared with NAWM and CWM. The 53BP1+ and p16+ cells were found significantly more abundant in acute active WMLs and GMLs, compared with chronic inactive lesions. Co-localization studies showed evidence of CS in neurons, astrocytes, oligodendrocytes, microglia, and macrophages. Among the quantified CSF SASP factors, IL-6, MIF, and MIP1a levels correlated with 53BP1+ cell counts in NAGM, whereas IL-10 levels correlated with p16+ cell counts in NAWM. P16+ cell counts in WMLs exhibited an inverse correlation with time to requiring a wheelchair and with age at death.

Our data indicates that CS primarily affects actively demyelinating gray and WMLs. A higher senescent cell load in P-MS is associated with faster disability progression and death. ANN NEUROL 2025;97:1074-1087.

Neurodegenerative diseases (NDDs) represent a rapidly escalating global health challenge, contributing significantly to the worldwide disease burden and posing substantial threats to public health systems across nations. Among the many risk factors for neurodegeneration, aging is the major risk factor. In the context of aging, multiple factors lead to the release of endogenous DNA (especially mitochondrial DNA, mtDNA), which is an important trigger for the activation of the cGAS-STING innate immune pathway. Recent studies have identified an increasing role for activation of the cGAS-STING signaling pathway as a driver of senescence-associated secretory phenotypes (SASPs) in aging and NDDs. The cGAS-STING pathway mediates the immune sensing of DNA and is a key driver of chronic inflammation and functional decline during the aging process. Blocking cGAS-STING signaling may reduce the inflammatory response by preventing mtDNA release and enhancing mitophagy. Targeted inhibition of the cGAS-STING pathway by biological macromolecules such as natural products shows promise in therapeutic strategies for age-related NDDs. This review aims to systematically and comprehensively introduces the role of the cGAS-STING pathway in age-related NDDs in the context of aging while revealing the molecular mechanisms of the cGAS-STING pathway and its downstream signaling pathways and to develop more targeted and effective therapeutic strategies for NDDs.

Accumulation of senescent cells is an increasingly recognized factor in the development and progression of cardiovascular (CV) disease (CVD). Senescent cells of different types display a pro-inflammatory and matrix remodelling molecular programme, known as the 'senescence-associated secretory phenotype' (SASP), which has roots in (epi)genetic changes. Multiple therapeutic options (senolytics, anti-SASP senomorphics, and epigenetic reprogramming) that delete or ameliorate cellular senescence have recently emerged. Some drugs routinely used in the clinics also have anti-senescence effects. However, multiple challenges hinder the application of novel anti-senescence therapeutics in the clinical setting. Understanding the biology of cellular senescence, advantages and pitfalls of anti-senescence treatments, and patients who can profit from these interventions is necessary to introduce this novel therapeutic modality into the clinics. We provide a guide through the molecular machinery of senescent cells, systematize anti-senescence treatments, and propose a pathway towards senescence-adapted clinical trial design to aid future efforts.

Diabetic wounds are common in patients with type 2 diabetes; they are ischemic and inflammatory, and difficult to heal without intervention. Hyperbaric oxygen therapy (HBOT) is a standard treatment, but its effectiveness is limited to a subset of the aging population. Senescent fibroblasts, a hallmark of aging, impair wound healing, and senolytic drugs, like quercetin (Q), which target senescent cells, may improve healing. In this study, we developed a mathematical model that defines biological aging through two parameters, η and [Formula: see text], that decline with age. These parameters reflect the biological age of an individual, where η represents fibroblast proliferation and [Formula: see text] represents the production of the angiogenetic protein VEGF. Our model predicts that treatment with only HBOT achieves wound closure, within normal expectable time, for patients with a limited subset pairs of [Formula: see text], and this subset is increased to a larger subset by combining Q with HBOT. The two subsets of [Formula: see text] are determined explicitly by simulations of the model. To make these results applicable in clinical setting, one will have to relate the aging parameters η and [Formula: see text] to tangible marks of biological-aging factors.

Cigarette smoke (CS) invokes an inflammatory response associated with vascular dysfunction and atherosclerosis. The role of sex and nicotine in CS effects on cardiovascular function and atherosclerosis is unexplored.

Male and female C57Bl/6 WT (wild type) and ApoE-/- mice were exposed to CS and nicotine with access to chow and water ad libitum for 16 weeks to fill this gap. Heart rate and endothelial function were measured in the aorta of WT mice, while the lipid profile, cytokines, chemokines, and plaque area and composition were assessed in ApoE-/- mice.

CS increased heart rate similarly in both sexes and induced a more substantial impairment in endothelial function in males and more plaque in females than nicotine. Necrotic core areas were similar for both treatments in both sexes, while females had higher collagen deposition across treatments. Both treatments elevated senescence-associated GLB1/-galactosidase (SA-GLB1) and interleukin 17A (IL17A) similarly in both sexes. CS upregulated cholesterol in both sexes, triglycerides, very low-density lipoprotein, high-density lipoprotein, and C-X-C motif chemokine ligand-5 (CXCL5/LIX) only in males, and LDL and IL1A only in females. Additionally, nicotine metabolism showed sex-specific responses to nicotine but not smoking.

Findings suggest that sex influences cardiovascular function and atherosclerosis following exposure to nicotine and CS.

The purpose of this study was to fill the existing literature gap through assessment of the differential sex effects of CS and nicotine on vascular function and atherosclerosis to identify sex-specific risk factors. We show sex-specific differences in endothelial function, plaque, inflammation, and extracellular matrix (ECM) regulators with exposure to CS and nicotine, which underscore the importance of assessing sex in tobacco and nicotine exposure studies. This study also shows the negative effect of oral nicotine administration as many oral dissolvable nicotine products, such as pouches and gum, are becoming increasingly popular among adolescents and young adults.

Despite not proliferating, senescent cells remain metabolically active to maintain the senescence program. However, the mechanisms behind this metabolic reprogramming are not well understood. We identify senescence-induced long noncoding RNA (sin-lncRNA), a previously uncharacterized long noncoding RNA (lncRNA), a key player in this response. While strongly activated in senescence by C/EBPβ, sin-lncRNA loss reinforces the senescence program by altering oxidative phosphorylation and rewiring mitochondrial metabolism. By interacting with dihydrolipoamide S-succinyltransferase (DLST), it facilitates its mitochondrial localization. Depletion of sin-lncRNA causes DLST nuclear translocation, leading to transcriptional changes in oxidative phosphorylation (OXPHOS) genes. While not expressed in highly proliferative cancer cells, it is strongly induced upon cisplatin-induced senescence. Depletion of sin-lncRNA in ovarian cancer cells reduces oxygen consumption and increases extracellular acidification, sensitizing cells to cisplatin treatment. Altogether, these results indicate that sin-lncRNA is specifically induced in senescence to maintain metabolic homeostasis, unveiling an RNA-dependent metabolic rewiring specific to senescent cells.

A detailed understanding of aging biology and the development of anti-aging therapeutic strategies remain imperative yet inherently challenging due to the protracted nature of aging. Cellular senescence arises naturally through replicative exhaustion and is accelerated by clinical treatments or environmental stressors. The accumulation of senescent cells-defined by a loss of mitogenic potential, resistance to apoptosis, and acquisition of a pro-inflammatory secretory phenotype-has been implicated as a key driver of chronic disease, tissue degeneration, and organismal aging. Recent studies have highlighted the therapeutic promise of senolytic drugs, which selectively eliminate senescent cells. Compelling results from preclinical animal studies and ongoing clinical trials underscore this potential. However, the clinical translation of senolytics requires further pharmacological validation to refine selectivity, minimize toxicity, and determine optimal dosing. Equally important is the evaluation of senolytics' potential to restore tissue structure and function by reducing the senescent cell burden. In vitro tissue culture models offer a powerful platform to advance these efforts. This review summarizes the current landscape of in vitro systems used for inducing cellular senescence-referred to as "senescence assays"-and for screening senolytic drugs-referred to as "senolytic assays". We conclude by discussing key challenges to improving mechanistic insight, predictive accuracy, and clinical relevance in senolytic drug development, as well as emerging applications of senolytic therapies.

Cellular senescence is characterized by irreversible cell-cycle exit, a pro-inflammatory secretory phenotype, macromolecular damage, and deregulated metabolism. Senescent cells are highly associated with age-related diseases. We previously demonstrated that targeted elimination of senescent cells prevents neurodegenerative disease in tau (MAPTP301S;PS19) mutant mice. Here, we show that genetic ablation of the senescence mediator p16Ink4a is sufficient to attenuate senescence signatures in PS19 mice. Disease phenotypes-including neuroinflammation, phosphorylated tau, neurodegeneration, and cognitive impairment-were blunted in the absence of p16Ink4a. Additionally, we found that PS19 mouse brains display p16Ink4-dependent neurovascular alterations such as vessel dilation, increased vessel density, deregulated endothelial cell extracellular matrix, and astrocytic endfoot depolarization. Finally, we show that p16Ink4a deletion in endothelial cells and microglia alone attenuates many of the same phenotypes. Altogether, these results indicate that neurodegenerative disease in PS19 mice is driven, at least in part, by p16Ink4a-expressing endothelial cells and microglia.

Polypyrimidine Tract Binding protein 1 (PTB) is an alternative splicing factor linked to neuronal induction and maturation. Previously, knockdown experiments supported a model in which PTB can function as a potent reprogramming factor, able to elicit direct glia-to-neuron conversion in vivo, in both the brain and retina. However, later lineage tracing and genetic knockouts of PTB did not support direct neuronal reprogramming. Nevertheless, consistent with the PTB depletion experiments, we show that antisense knockdown of PTB (ptbp1a) in the zebrafish retina can activate Müller glia-derived proliferation and that depletion of PTB can further enhance proliferation when combined with acute NMDA damage. The effects of PTB are consistent with a role in controlling key senescence and pro-inflammatory genes that are part of the senescence secretome that initiates retina regeneration.

The central nervous system (CNS), comprising the brain, spinal cord, and optic nerve, has limited regenerative capacity, posing significant challenges in treating neurological disorders. Recent advances in neuroscience and neurotherapeutics have introduced promising strategies to stimulate CNS repair, particularly in the context of neurodegenerative diseases such as multiple sclerosis. This review explores the complex interplay between inflammation, demyelination, and remyelination possibilities. Glial cells, including oligodendrocyte precursors, oligodendrocytes, astrocytes and microglia play dual roles in injury response, with reactive gliosis promoting repair but also potentially inhibiting recovery through glial scar formation. There is also an emphasis on axonal regeneration, axonal sprouting and stem cell therapies. We highlight the role of neuroplasticity in recovery post-injury and the limited regenerative potential of axons in the CNS due to inhibitory factors such as myelin-associated inhibitors. Moreover, neurotrophic factors support neuronal survival and axonal growth, while stem cell-based approaches offer promise for replacing lost neurons and glial cells. However, challenges such as stem cell survival, integration, and risk of tumor formation remain. Furthermore, we examine the role of neurogenesis in CNS repair and the remodeling of the extracellular matrix, which can facilitate regeneration. Through these diverse mechanisms, ongoing research aims to overcome the intrinsic and extrinsic barriers to CNS repair and advance therapeutic strategies for neurological diseases.

Ginsenoside Rg1 is a key bioactive compound in ginseng, a traditional herbal medicine known for tonifying qi and nourishing blood, traditionally used to replenish "qi" by regulating hematopoietic function. But its underlying mechanism remains to be elucidated.

This study aims to delve into the role of Rg1 on senescent hematopoiesis and its mechanisms.

A model of D-galactose-induced hematopoietic injury was established with ginsenoside Rg1. The hematopoietic supportive effect of Rg1 was assessed by quantifying the levels of hematopoietic supportive factors VCAM1, CXCL12 and SCF, CFU-Mix formation and cellular senescence; and the levels of inflammatory factors and oxidative stress were measured by ELISA in the serum and cellular supernatant of mice. Co-culture technique was used to examine the ability of Rg1 to restore impaired hematopoiesis by improving the inflammatory hematopoietic microenvironment. For mechanism exploration, RNA-Seq was used to detect differential genes in Rg1-treated MSCs, GO- and KEGG-based enrichment analyses were used to screen the key pathways in which Rg1 exerts its effects, and molecular docking was used to demonstrate the feasibility of molecular interconnections between Rg1 and TLR2. To further explore the mechanism, pathway activators were further used and the expression levels of target proteins downstream of the TLR2 pathway were quantified using Western blotting.

Rg1 decreased the levels of inflammatory factors IL-1β, IL-6 and TNFα, while enhancing the expression of hematopoietic support factors in senescent MSCs, thereby improving the self-renewal and differentiation of aged HSPCs. Additionally, Rg1 also delayed HSPC senescence and reduced the level of oxidative stress. KEGG and GO were enriched for the Toll/NF-κB signaling pathway, based on differential genes obtained by transcriptional sequencing. Rg1 could inhibit the elevated levels of MyD88, NF-κB-p65 and IκBα proteins, and their phosphorylation levels by binding to TLR2 protein and inhibiting them. In conclusion, Rg1 ameliorates the inflammatory hematopoietic microenvironment induced by MSCs senescence via the TLR2/NF-κB-p65 signaling pathway, alleviating HSPCs senescence.

Our results reveal the mechanism by which Rg1 regulates HSPCs function and represent a potential therapeutic strategy for hematopoietic dysfunction, highlighting the potential value of traditional Chinese medicine extracts in clinical applications.

Senescence in stem cells and progenitor cells can be particularly detrimental because these cells are essential for tissue renewal and overall organismal homeostasis. In mesenchymal stromal cells (MSCs), which comprise a heterogeneous mix of stem cells, progenitors, fibroblasts, and other stromal cells, senescence poses a significant challenge, as it impairs their ability to support tissue repair and maintenance. This decline in regenerative capacity can contribute to aging-related diseases, impaired wound healing, and degenerative disorders. One hallmark of senescence is resistance to apoptosis, mediated by activation of anti-apoptotic pathways. Consequently, senotherapeutics have emerged as a promising strategy to selectively eliminate senescent cells and promote healthy aging. Plant secondary metabolites, notably polyphenols and terpenes, exhibit diverse effects on living organisms and have served as medicinal agents.

In this study, we investigated four terpenes-carvacrol, thymol, eugenol, and lycopene-for their senolytic potential in human senescent MSCs.

We found that these compounds induce apoptosis through both caspase-dependent and caspase-independent mechanisms, involving the activation of BAX, cytochrome c release, and translocation of apoptosis-inducing factor (AIF) from mitochondria to nuclei. Importantly, terpene-induced apoptosis was associated with a significant increase in reactive oxygen species, and pre-incubation with glutathione partially rescued cell viability, confirming oxidative stress as a central trigger. Moreover, we identified SRC pathway modulation as a critical determinant of the senescence-to-apoptosis shift, highlighting a key regulatory switch in terpene action.

These findings provide a detailed mechanistic dissection of terpene-induced senolysis and underscore their potential as promising candidates for senotherapeutics targeting senescent cells.

Skin is the largest organ of the human body and undergoes both intrinsic (chronological) and extrinsic aging. While intrinsic skin aging is driven by genetic and epigenetic factors, extrinsic aging is mediated by external threats such as UV irradiation or fine particular matters, the sum of which is referred to as exposome. The clinical manifestations and biochemical changes are different between intrinsic and extrinsic skin aging, albeit overlapping features exist, eg, increased generation of reactive oxygen species, extracellular matrix degradation, telomere shortening, increased lipid peroxidation, or DNA damage. As skin is a prominent target for many hormones, the molecular and biochemical processes underlying intrinsic and extrinsic skin aging are under tight control of classical neuroendocrine axes. However, skin is also an endocrine organ itself, including the hair follicle, a fully functional neuroendocrine "miniorgan." Here we review pivotal hormones controlling human skin aging focusing on IGF-1, a key fibroblast-derived orchestrator of skin aging, of GH, estrogens, retinoids, and melatonin. The emerging roles of additional endocrine players, ie, α-melanocyte-stimulating hormone, a central player of the hypothalamic-pituitary-adrenal axis; members of the hypothalamic-pituitary-thyroid axis; oxytocin, endocannabinoids, and peroxisome proliferator-activated receptor modulators, are also reviewed. Until now, only a limited number of these hormones, mainly topical retinoids and estrogens, have found their way into clinical practice as anti-skin aging compounds. Further research into the biological properties of endocrine players or its derivatives may offer the development of novel senotherapeutics for the treatment and prevention of skin aging.

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.

The aging of the population is a global concern. In the post-coronavirus disease 2019 (COVID-19) pandemic era, there are no effective methods to identify aging acceleration due to infection. In this study, we conducted whole-transcriptome sequencing on peripheral blood samples from 35 healthy individuals (22-88 years old). By analyzing the changes in mRNA, lncRNA, and miRNA expression, we investigated the characteristics of transcriptome alterations during the aging process. ceRNA networks were constructed, and 10 genes (CD248, PHGDH, SFXN2, MXRA8, NOG, TTC24, PHYKPL, CACHD1, BPGM, and TWF1) were identified as potential aging markers and used to construct an aging clock. Moreover, our aging clock categorized individuals into slow-, average-, and quick-aging groups, highlighting a link between accelerated aging and infection-related clinical parameters. Pseudotime analysis further revealed 2 distinct aging trajectories, corroborating the variations in the aging rate identified by the aging clock. Furthermore, we validated the results using the OEP001041 data set (277 healthy individuals aged 17-75), and data sets comprising patients with infectious diseases (n = 1 558). Our study revealed that infection accelerates aging via increased inflammation and oxidative stress in infectious disease patients. Besides, the aging clock exhibited alterations after infection, highlighting its potential for assessing the aging rate after patient recovery. In conclusion, our study introduces a novel aging clock to assess the aging rate in healthy individuals and those with infections, revealing a strong link between accelerated aging and infections through inflammation and oxidative stress. These findings offer valuable insights into aging mechanisms and potential strategies for healthy aging.

In recent years, aging and cellular senescence have triggered an increased interest in corresponding research fields. Evidence shows that the complex aging process is involved in the development of many chronic liver diseases, such as metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH). In fact, aging has a tremendous effect on the liver, leading to a gradual decline in the metabolism, detoxification and immune functions of the liver, which in turn increases the risk of liver disease. These changes can be based on the aging of liver cells (hepatocytes, liver sinusoidal endothelial cells, hepatic stellate cells, and Kupffer cells). Similarly, patients with liver diseases exhibit increases in the aging phenotype and aging cells, often manifesting as faster physical functional decline, which is closely related to the promoting effect of liver disease on aging. This review summarizes the interplay between MASLD/MASH development and aging, aiming to reveal the complex relationships that exacerbate one another. Moreover, the corresponding schemes for delaying aging or treating diseases are discussed to provide a basis for the development of effective prevention and treatment strategies in the future.

Several bat species live >20-40 years, suggesting that they possess efficient anti-aging and anti-cancer defenses. Here we investigate the requirements for malignant transformation in primary fibroblasts from four bat species Myotis lucifugus, Eptesicus fuscus, Eonycteris spelaea, and Artibeus jamaicensis - spanning the bat evolutionary tree and including the longest-lived genera. We show that bat fibroblasts do not undergo replicative senescence, express active telomerase, and show attenuated SIPs with dampened secretory phenotype. Unexpectedly, unlike other long-lived mammals, bat fibroblasts are readily transformed by two oncogenic "hits": inactivation of p53 or pRb and activation of HRASG12V. Bat fibroblasts exhibit increased TP53 and MDM2 transcripts and elevated p53-dependent apoptosis. M. lucifugus shows a genomic duplication of TP53. We hypothesize that some bat species have evolved enhanced p53 activity as an additional anti-cancer strategy, similar to elephants. Further, the absence of unique cell-autonomous tumor suppressive mechanisms may suggest that in vivo bats may rely on enhanced immunosurveillance.

Aging is associated with a gradual decline in cellular function, largely driven by oxidative stress, which leads to cellular senescence. These processes contribute to tissue degeneration and age-related dysfunction. Human dermal fibroblasts (HDFs), critical for maintaining skin structure, are highly vulnerable to oxidative damage, making them key contributors to skin aging. Umbilical cord blood plasma (UCBP), rich in growth factors and regenerative molecules, has shown potential in preventing cellular senescence and addressing key mechanisms of tissue aging. Based on findings from heterochronic parabiosis experiments that demonstrated the rejuvenating effect of young blood, we investigated the effects of UCBP on hydrogen peroxide (H2O2) induced oxidative stress in HDFs and compared its efficacy with adult blood plasma (ABP). Our results indicate that although both UCBP and ABP reduce reactive oxygen species (ROS), UCBP is more effective in suppressing cellular senescence and maintaining fibroblast proliferation. These findings suggest that UCBP's protective effects extend beyond ROS reduction, potentially by modulating the senescence-associated secretory phenotype and the enhancement of tissue repair mechanisms.

Understanding the complex relationship between cancer and immune surveillance is essential for leveraging the immune system to control tumor growth. In our study, we discovered that activating the Kv11.1 potassium channel in ER+ breast cancer cells induces a senescent phenotype, which in turn triggers a potent immune response against these senescent cells. Specifically, we found that the senescence-associated secretory phenotype (SASP) plays a crucial role in activating CD4+ T-helper 1 (Th1) cells and memory T cell phenotypes. This activation led to the release of tumor necrosis factor-alpha (TNFα), which induced the death of senescent breast cancer cells, independent of their resistance to endocrine therapy. Our findings suggest that Kv11.1 channel-induced cellular senescence in ER+ breast cancer cells is a key mechanism in immune surveillance, driving a lethal immune response through TNFα. These results highlight the potential immunomodulatory role of Kv11.1 activation in ER-positive breast cancer and provide a foundation for future therapeutic investigations.

Accumulation of senescent neurons in the dorsal root ganglion (DRG) is an important tissue phenotype that causes age-related degeneration of peripheral sensory nerves. Senescent neurons are neurons with arrested cell cycle that have undergone cellular senescence but remain in the tissue and play various biological roles. To understand the accumulation of senescent neurons in the DRG during aging, we aimed to elucidate the mechanism that induces cellular senescence in DRG neurons and the role of senescent DRG neurons. We integrated multiple public transcriptome datasets for DRGs, which include cell bodies in neurons, and the sciatic nerve, which includes axons in neurons, using network medicine-based bioinformatics analysis. We thus inferred the molecular mechanisms involved in cellular senescence of DRG neurons, from molecular responses to senescence, in the DRG-sciatic nerve network. Network medicine-based bioinformatics analysis revealed that age-related Mapk3 decline leads to impaired cholesterol metabolism and biosynthetic function in axons, resulting in compensatory upregulation of Srebf1, a transcription factor involved in lipid and cholesterol metabolism. This in turn leads to CDKN2A-mediated cellular senescence. Furthermore, our analysis revealed that senescent DRG neurons develop a senescence phenotype characterized by activation of antigen-presenting cells via upregulation of Ctss as a hub gene. B cells were inferred as antigen-presenting cells activated by Ctss, and CD8-positive T cells were inferred as cells that receive antigen presentation from B cells.

We tested the ability of a single intravitreal injection of foselutoclax (hereafter UBX1325), a novel senolytic small molecule inhibitor of antiapoptotic protein B-cell lymphoma-extra large, to mitigate the impact of diabetic macular edema.

Patients with diabetic macular edema with prior suboptimal response to anti-vascular endothelial growth factor treatment were randomly assigned (1:1) to either a single intravitreal injection of 10 μg of UBX1325 or sham and were followed for up to 48 weeks. The primary trial objective was to evaluate the safety and side-effect profile of UBX1325 as assessed by ocular and systemic treatment-emergent adverse events (TEAEs). Our secondary objective was to probe efficacy, defined as mean changes from baseline for UBX1325 versus sham in best corrected visual acuity measured in Early Treatment of Diabetic Retinopathy Study (ETDRS) letters (range, 0-100 letters, higher scores indicate better vision) and retinal structure.

Between June 2021 and April 2022, 65 participants (32.3% women) were randomly assigned to either UBX1325 (n=32) or sham (n=33). There were four TEAEs of Grade 3 or greater in the sham group, of which three were considered serious, while there were five in the UBX1325 group of Grade 3 or greater and considered serious. There were no apparent between-group differences with respect to vital signs, electrocardiograms, or routine blood chemistries. For the secondary outcome of efficacy, the difference between UBX1325 and sham in mean change to week 48 in best corrected visual acuity was 5.6 more ETDRS letters (95% confidence interval, -1.5 to 12.7).

In this sham-controlled trial there were no TEAEs that led to discontinuation of treatment with UBX1325 compared with sham. There were trends suggestive of potential efficacy; larger trials are needed to further evaluate these findings. (Funded by UNITY Biotechnology; ClinicalTrials.gov number, NCT04857996.).

Neutrophils have recently received increased attention in cancer because they contribute to all stages of cancer. Neutrophils are so far considered to have a short half-life. However, a growing body of literature has shown that tumor-associated neutrophils (TANs) acquire a prolonged lifespan. This review discusses recent work surrounding the mechanisms by which neutrophils can persist in the tumor microenvironment (TME). It also highlights different scenarios for therapeutic targeting of protumorigenic neutrophils, supporting the idea that, in tumors, inhibition of neutrophil recruitment is not sufficient because these cells can persist and remain hidden from current interventions. Hence, the elimination of long-lived neutrophils should be pursued to increase the efficacy of standard therapy.

Centrosome abnormalities are a distinguishing feature of cancer and play a role in the aging process. Cancer cells may evade the immune system by activating immune checkpoints, altering their surrounding microenvironment, abnormalities in antigen presentation and recognition, and metabolic reprogramming to inhibit T-cell activity, allowing cancer cells to survive and spread within the host. When the centrosomes are abnormally shaped or numbered, mitotic errors can occur, cellular senescence occurs, cell death occurs, genomic instability occurs, and aneuploidy forms, resulting in diseases such as cancer. The present study is exploring the strategy of research progress in which centrosome abnormalities contribute to the aging process in various different ways as well as fuel immune escape from cancer cells, providing a new direction for cancer immunotherapy.

Aging is associated with the accumulation of senescent cells, which are triggered by tissue injury response and often escape clearance by the immune system. The specific traits and diversity of these cells in aged tissues, along with their effects on the tissue microenvironment, remain largely unexplored. Despite the advances in single-cell and spatial omics technologies to understand complex tissue architecture, senescent cell populations are often neglected in general analysis pipelines due to their scarcity and the technical bias in current omics toolkits. Here we used the physical properties of tissue to enrich the age-associated fibrotic niche and subjected them to single-cell RNA sequencing and single-nuclei ATAC sequencing (ATAC-seq) analysis and named this method fibrotic niche enrichment sequencing (FiNi-seq). Fibrotic niche of the tissue was selectively enriched based on its resistance to enzymatic digestion, enabling quasi-spatial analysis. We profiled young and old livers of male mice using FiNi-seq, discovered Wif1- and Smoc1-producing mesenchymal cell populations showing senescent phenotypes, and investigated the early immune responses within this fibrotic niche. Finally, FiNi-ATAC-seq revealed age-associated epigenetic changes enriched in fibrotic niche cells. Thus, our quasi-spatial, single-cell profiling method allows the detailed analysis of initial aging microenvironments, providing potential therapeutic targets for aging prevention.

Aging is characterized by a steady loss of physiological integrity, leading to impaired function and increased vulnerability to death. Cell senescence is a biological process that progresses with aging and is believed to be a key driver of age-related diseases. Senescence, a hallmark of aging, also demonstrates its beneficial physiological aspects as an anti-cancer, pro-regenerative, homeostatic, and developmental mechanism. A transitory response in which the senescent cells are quickly formed and cleared may promote tissue regeneration and organismal fitness. At the same time, senescence-related secretory phenotypes associated with extended senescence can have devastating effects. The fact that the interaction between senescent cells and their surroundings is very context-dependent may also help to explain this seemingly opposing pleiotropic function. Further, mitochondrial dysfunction is an often-unappreciated hallmark of cellular senescence and figures prominently in multiple feedback loops that induce and maintain the senescent phenotype. This review summarizes the mechanism of cellular senescence and the significance of acute senescence. We concisely introduced the context-dependent role of senescent cells and SASP, aspects of mitochondrial biology altered in the senescent cells, and their impact on the senescent phenotype. Finally, we conclude with recent therapeutic advancements targeting cellular senescence, focusing on acute injuries and age-associated diseases. Collectively, these insights provide a future roadmap for the role of senescence in organismal fitness and life span extension.

Pituitary tumors are characterized by slow proliferation rates and a high prevalence within the population. The pathogenesis of these tumors remains incompletely understood, although accumulating evidence suggests that the activation of the cellular senescence program, triggered by various stressors and functioning as a brake on cellular proliferation, may contribute to their typically benign nature. Multiple mediators of the senescence response are implicated in this process. Interleukin-6 (IL-6), a proinflammatory cytokine, plays a dual role in pituitary tumor biology. It is involved in both physiological pituitary growth and the senescence-associated secretory phenotype (SASP), where it mediates paracrine-proliferative signals. In addition to its secretory functions, IL-6 has been implicated in the regulation of pituitary senescence through non-secretory mechanisms. Other factors, such as growth hormone (GH), the pituitary tumor-transforming gene (PTTG), and interactions within the tumor microenvironment, including immune cell dynamics, also contribute to the senescence observed in these tumors. This review examines the latest evidence concerning the role of senescence in pituitary tumors, with a particular focus on the contribution of IL-6 to this process.

Cellular senescence contributes to a variety of pathologies associated with aging and is implicated as a cellular state in which cancer cells can survive treatment. Reported senolytic drug treatments act through varying molecular mechanisms, but heterogeneous efficacy across the diverse contexts of cellular senescence indicates a need for predictive biomarkers of senolytic activity. Using multi-parametric analyses of commonly reported molecular features of the senescent phenotype, we assayed a variety of models, including malignant and nonmalignant cells, using several triggers of senescence induction and found little univariate predictive power of these traditional senescence markers to identify senolytic drug sensitivity. We sought to identify novel drug targets in senescent cells that were insensitive to frequently implemented senolytic therapies, such as Navitoclax (ABT-263), using quantitative mass spectrometry to measure changes in the senescent proteome, compared to cells which acquire an acute sensitivity to ABT-263 with senescence induction. Inhibition of the antioxidant GPX4 or the Bcl-2 family member MCL-1 using small molecule compounds in combination with ABT-263 significantly increased the induction of apoptosis in some, but not all, previously insensitive senescent cells. We then asked if we could use BH3 profiling to measure differences in mitochondrial apoptotic priming in these models of cellular senescence and predict sensitivity to the senolytics ABT-263 or the combination of dasatinib and quercetin (D + Q). We found, despite being significantly less primed for apoptosis overall, the dependence of senescent mitochondria on BCL-XL was significantly correlated to senescent cell killing by both ABT-263 and D + Q, despite no significant changes in the gene or protein expression of BCL-XL. However, our data caution against broad classification of drugs as globally senolytic and instead provide impetus for context-specific senolytic targets and propose BH3 profiling as an effective predictive biomarker.

There is a sex bias in the incidence and progression of many kidney diseases. To better understand such sexual dimorphism, we integrated data from six platforms, characterizing 76 kidney samples from 68 mice at six developmental and adult time points, creating a molecular atlas of the mouse kidney across the lifespan for both sexes. We show that proximal tubules have the most sex-biased differentially expressed genes emerging after 3 weeks of age and are associated with hormonal regulations. We reveal potential mechanisms involving both direct and indirect regulation by androgens and estrogens. Spatial profiling identifies distinct sex-biased spatial patterns in the cortex and outer stripe of the outer medulla. Additionally, older mice exhibit more aging-related gene alterations in loops of Henle, proximal tubules and collecting ducts in a sex-dependent manner. Our results enhance the understanding of spatially resolved gene expression and hormone regulation underlying kidney sexual dimorphism across the lifespan.