Eliminating Senescent Cells Can Promote Pulmonary Hypertension Development and Progression

Aging at the Crossroads of Organ Interactions: Implications for the Heart

Aging processes underlie common chronic cardiometabolic diseases such as heart failure and diabetes. Cross-organ/tissue interactions can accelerate aging through cellular senescence, tissue wasting, accelerated atherosclerosis, increased vascular stiffness, and reduction in blood flow, leading to organ remodeling and premature failure. This interorgan/tissue crosstalk can accelerate aging-related dysfunction through inflammation, senescence-associated secretome, and metabolic and mitochondrial changes resulting in increased oxidative stress, microvascular dysfunction, cellular reprogramming, and tissue fibrosis. This may also underscore the rising incidence and co-occurrence of multiorgan dysfunction in cardiometabolic aging in the population. Examples include interactions between the heart and the lungs, kidneys, liver, muscles, and brain, among others. However, this phenomenon can also present new translational opportunities for identifying diagnostic biomarkers to define early risks of multiorgan dysfunction, gain mechanistic insights, and help to design precision-directed therapeutic interventions. Indeed, this opens new opportunities for therapeutic development in targeting multiple organs simultaneously to disrupt the crosstalk-driven process of mutual disease acceleration. New therapeutic targets could provide synergistic benefits across multiple organ systems in the same at-risk patient. Ultimately, these approaches may together slow the aging process itself throughout the body. In the future, with patient-centered multisystem coordinated approaches, we can initiate a new paradigm of multiorgan early risk prediction and tailored intervention. With emerging tools including artificial intelligence-assisted risk profiling and novel preventive strategies (eg, RNA-based therapeutics), we may be able to mitigate multiorgan cardiometabolic dysfunction much earlier and, perhaps, even slow the aging process itself.

Therapeutic targets for pulmonary arterial hypertension: insights into the emerging landscape

BACKGROUND

Pulmonary arterial hypertension (PAH) is a progressive, life-threatening disease driven by vascular remodeling, right ventricular (RV) dysfunction, and metabolic and inflammatory dysregulation. Current therapies primarily target vasodilation to relieve symptoms but do not reverse disease progression. The recent approval of sotatercept, which modulates BMP/TGF-β signaling, marks a shift toward anti-remodeling therapies. Building on this, recent preclinical advances have identified promising therapeutic targets and potentially disease-modifying treatments.

AREAS COVERED

This review synthesizes the evolving preclinical landscape of emerging PAH therapeutic targets and drugs, highlighting innovative approaches aimed at addressing the underlying mechanisms of disease progression. Additionally, we discuss novel therapeutic strategies under development.

EXPERT OPINION

Recent advances in PAH research have identified novel therapeutic targets beyond vasodilators, including modulation of BMP/TGF-β signaling, metabolic programs, epigenetics, cancer-related signaling, the extracellular matrix, and immune pathways, among others. Sotatercept represents a significant advance in therapies that go beyond vasodilation, and long-term safety, efficacy, and durability are being assessed. Future treatment strategies will focus on precision approaches, noninvasive technologies, and regenerative biology to improve outcomes and reverse vascular remodeling.

Intersection of Cardio-Oncology: An Overview of Radiation-Induced Heart Disease in the Context of Tumors

Radiation-induced heart disease (RIHD) is a prevalent cardiovascular complication of radiation therapy, with coronary heart disease being the most common manifestation. Clinical presentations of RIHD vary and may include conduction abnormalities, ischemic heart disease, cardiomyopathy, heart failure, and valvular damage. Even low doses of radiation significantly increase the risk of cardiovascular disease, often associated with severe stenosis detected via angiography. Radiation-induced damage to the cardiac endothelium triggers inflammatory responses and oxidative stress, which contribute to the progression of atherosclerosis. This study explores how radiation activates multiple signaling pathways through the generation of reactive oxygen species, resulting in vascular endothelial damage, cellular senescence, inflammatory responses, and DNA damage. It further examines the impact of radiation on vascular integrity and tight junction proteins, leading to increased vascular permeability and infiltration by inflammatory cells. From a clinical perspective, we emphasize the challenges posed by the coexistence of tumors in many patients with RIHD, as tumors complicate the microenvironment and may have mutually reinforcing interactions with radiation-induced damage. We also discuss various therapeutic strategies, including novel approaches targeting cellular senescence and immune responses, with a focus on the potential use of navitoclax and IL-6 (interleukin-6) inhibitors to prevent irreversible cardiomyocyte fibrosis and ongoing vascular damage. In conclusion, RIHD is a multifaceted disease involving complex biological processes and signaling pathways. Early intervention and targeted therapies are crucial for improving patient outcomes. Future research should prioritize uncovering the molecular mechanisms of RIHD and developing more effective therapeutic strategies.

New LFA-1 inhibitor Orientin reduces angiotensin II-induced vascular remodeling

BACKGROUND

The interaction between monocytes and vascular endothelium often leads to inflammatory reactions and vascular remodeling. The lymphocyte function-associated antigen 1 (LFA1) plays a crucial role in promoting leukocyte adhesion and migration during inflammatory diseases. However, the role of LFA1 in angiotensin II (Ang II)-induced hypertension and vascular remodeling is not clear. Orientin (Ori) has antioxidant, anti-inflammatory, anticancer, and resistance to myocardial remodeling. However, the role of Orientin remains unclear in angiotensin II (Ang II)-induced hypertension and vascular remodeling.

METHODS

In this study, Ang II was used to induce hypertension in mice. We employed various techniques including blood pressure monitoring, pathological staining, Immunofluorescent and Immunohistochemical staining, real time-PCR, vasodilation analysis and other methods to study whether LFA1 antibody and Orientin can regulate vascular remoding.

RESULTS

Our results showed that LFA1 significantly improved Ang II-induced hypertension, inflammation, fibrosis, and oxidative stress. Furthermore, in vitro experiments have substantiated that the use of neutralizing antibodies targeting LFA1 can effectively hinder the migration of macrophages to endothelial cells, which is triggered by Ang II. Additionally, the antibodies also reduce the extent of DNA damage and oxidative stress. Orientin can interact with LFA-1. Then, it was proved by pathological staining that Orientin can inhibit Ang II-induced vascular remodeling.

CONCLUSION

Here, we identified Orientin as a small molecule inhibitor of LFA-1 with anti-vascular remodeling function. These findings not only suggest that Orientin is a promising compound for the clinical treatment of vascular injury and hypertension, but also provide strategies for the treatment of cardiovascular diseases.

Piezo1 in PASMCs: Critical for Hypoxia-Induced Pulmonary Hypertension Development

BACKGROUND

Pulmonary hypertension (PH) is a life-threatening and progressive yet incurable disease. The hallmarks of PH comprise (1) sustained contraction and (2) excessive proliferation of pulmonary arterial smooth muscle cells (PASMCs). A major stimulus to which PASMCs are exposed during PH development is altered mechanical stress, originating from increased blood pressure, changes in blood flow velocity, and a progressive stiffening of pulmonary arteries. Mechanosensitive ion channels, including Piezo1 (Piezo-type mechanosensitive ion channel component-1), perceive such mechanical stimuli and translate them into a variety of cellular responses, including contractility or proliferation. Thus, the objective of the present study was to elucidate the specific role of Piezo1 in PASMCs for PH development and progression.

METHODS

The cell-type specific function of Piezo1 in PH was assessed in (1) PASMCs and lung tissues from patients with PH and (2) 2 mouse strains characterized by smooth muscle cell-specific, conditional Piezo1 knockout. Taking advantage of these strains, the smooth muscle cell-specific role of Piezo1 in PH development and progression was assessed in isolated, perfused, and ventilated mouse lungs, wire myography, and proliferation assays. Finally, in vivo function of smooth muscle cell-specific Piezo1 knockout was evaluated upon induction of chronic hypoxia-induced PH in these mice with insights into pulmonary vascular cell senescence.

RESULTS

Compared with healthy controls, PASMCs from patients with PH featured an elevated Piezo1 expression and increased proliferative phenotype. Smooth muscle cell-specific Piezo1 deletion, as confirmed via quantitative real-time polymerase chain reaction and patch clamp recordings, prevented the hypoxia-induced increase in PASMC proliferation in mice. Moreover, Piezo1 knockout reduced hypoxic pulmonary vasoconstriction in isolated, perfused, and ventilated mouse lungs, endothelial-denuded pulmonary arteries, and hemodynamic measurements in vivo. Consequently, Piezo1-deficient mice were considerably protected against chronic hypoxia-induced PH development with ameliorated right heart hypertrophy and improved hemodynamic function. In addition, distal pulmonary capillaries were preserved in the Piezo1-knockout mice, associated with a lower number of senescent endothelial cells.

CONCLUSIONS

This study provides evidence that Piezo1 expressed in PASMCs is critically involved in the pathogenesis of PH by controlling pulmonary vascular tone, arterial remodeling, and associated lung capillary rarefaction due to endothelial cell senescence.

NAT10 mediates TLR2 to promote podocyte senescence in adriamycin-induced nephropathy

N-acetyltransferase 10 (NAT10) is involved in regulating senescence. However, its role in glomerular diseases remains unclear. Therefore, this study aims to investigate the mechanisms by which NAT10 influences senescence and damage in an adriamycin (ADR)-induced nephropathy model. Senescence (p16 and p21) and DNA damage markers (γ-H2AX (ser139)) were assessed in ADR-induced nephropathy. NAT10 function was demonstrated using Remodelin or small interfering RNA (siRNA) interventions. Transcriptome sequencing was conducted to identify key downstream genes and pathways, while coimmunoprecipitation was performed to evaluate the relationship between NAT10 and toll-like receptor 2 (TLR2) expression. TLR2 overexpression or knockdown further validated its regulatory role in senescence. In ADR-treated mice, the expression levels of P53, P21, P16, γ-H2AX(S139) proteins were elevated, while those of WT-1 and nephrin were reduced. This effect was mitigated by Remodelin and siNAT10 administration. Transcriptome sequencing identified TLR2 as a key downstream gene, and coimmunoprecipitation, along with molecular docking models, confirmed its interaction with NAT10. TLR2 overexpression plasmid or siRNA was employed for recovery experiments. Together, the study findings suggest that NAT10 contributes to podocyte senescence and injury via interaction with TLR2. Further, it demonstrates that NAT10 alleviates ADR-induced podocyte senescence by interacting with TLR2, potentially through a P53-P21-dependent mechanism. Thus NAT10 could serve as a novel therapeutic target for treating podocyte senescence and proteinuric glomerulopathies.

Functions and application of circRNAs in vascular aging and aging-related vascular diseases

Circular RNAs (circRNAs), constituting a novel class of endogenous non-coding RNAs generated through the reverse splicing of mRNA precursors, possess the capacity to regulate gene transcription and translation. Recently, the pivotal role of circRNAs in controlling vascular aging, as well as the pathogenesis and progression of aging-related vascular diseases, has garnered substantial attention. Vascular aging plays a crucial role in the increased morbidity and mortality of the elderly. Endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) are crucial components of the intima and media layers of the vascular wall, respectively, and are closely involved in the mechanisms underlying vascular aging and aging-related vascular diseases. The review aims to provide a comprehensive exploration of the connection between circRNAs and vascular aging, as well as aging-related vascular diseases. Besides, circRNAs, as potential diagnostic markers or therapeutic targets for vascular aging and aging-related vascular diseases, will be discussed thoroughly, along with the challenges and limitations of their clinical application. Investigating the role and molecular mechanisms of circRNAs in vascular aging and aging-related vascular diseases will provide a novel insight into early diagnosis and therapy, and even effective prognosis assessment of these conditions.

Targeting senescent cells for the treatment of age-associated diseases

Cellular senescence, which entails cellular dysfunction and inflammatory factor release-the senescence-associated secretory phenotype (SASP)-is a key contributor to multiple disorders, diseases and the geriatric syndromes. Targeting senescent cells using senolytics has emerged as a promising therapeutic strategy for these conditions. Among senolytics, the combination of dasatinib and quercetin (D + Q) was the earliest and one of the most successful so far. D + Q delays, prevents, alleviates or treats multiple senescence-associated diseases and disorders with improvements in healthspan across various pre-clinical models. While early senolytic therapies have demonstrated promise, ongoing research is crucial to refine them and address such challenges as off-target effects. Recent advances in senolytics include new drugs and therapies that target senescent cells more effectively. The identification of senescence-associated antigens-cell surface molecules on senescent cells-pointed to another promising means for developing novel therapies and identifying biomarkers of senescent cell abundance.

[Senescence of the pulmonary endothelial cells: VEGF, a new target in pulmonary pathologies and aging]

Vascular aging leading to microvessel depletion is a key element of organismal aging. The proposed mechanism is a deficiency of vascular endothelial growth factor (VEGF) signaling in the endothelial cells (EC), linked to the increase of a receptor in a soluble form (sVEGFR1) preventing VEGF from binding to its active receptor (VEGFR2). Without the VEGF survival signal, ECs may become senescent, contributing to aging and to various pulmonary pathologies. Deficiency of VEGF signaling in EC senescence could represent a determining element of lung aging and diseases such as pulmonary hypertension (PH) and emphysema.

Unveiling the cell-type-specific landscape of cellular senescence through single-cell transcriptomics using SenePy

Senescent cells accumulate in most tissues with organismal aging, exposure to stressors, or disease progression. It is challenging to identify senescent cells because cellular senescence signatures and phenotypes vary widely across distinct cell types and tissues. Here we developed an analytical algorithm that defines cell-type-specific and universal signatures of cellular senescence across a wide range of cell types and tissues. We utilize 72 mouse and 64 human weighted single-cell transcriptomic signatures of cellular senescence to create the SenePy scoring platform. SenePy signatures better recapitulate in vivo cellular senescence than signatures derived from in vitro senescence studies. We use SenePy to map the kinetics of senescent cell accumulation in healthy aging as well as multiple disease contexts, including tumorigenesis, inflammation, and myocardial infarction. SenePy characterizes cell-type-specific in vivo cellular senescence and could lead to the identification of genes that serve as mediators of cellular senescence and disease progression.

A galactose-tethered tetraphenylethene prodrug mediated apoptosis of senescent cells for osteoporosis treatment

Osteoporosis and bone injury healing in elderly patients are major medical challenges, often exacerbated by the accumulation of senescent cells. Herein, we show that TPE-Gal, which contains a tetraphenylethene unit and a galactose moiety, offers a promising molecular therapy designed to light up and eliminate senescent cells through a hydrolysis reaction catalyzed by β-galactosidase, an enzyme overexpressed in senescent cells. The reaction produces TPE-OH, which, in turn, increases reactive oxygen species levels within the senescent cells, leading to noninflammatory apoptosis of senescent cells. This targeted clearance mechanism helps to alleviate osteoporosis symptoms and promotes bone injury healing. Moreover, apoptotic vesicles, which are generated during the process, are partly phagocytosed by macrophages, mimicking physiological metabolic processes. This study opens new avenues for addressing bone health issues through the designed bioclearance of senescent cells, aligning with the body's natural pathways for maintaining homeostasis.

Unraveling AURKB as a potential therapeutic target in pulmonary hypertension using integrated transcriptomic analysis and pre-clinical studies

Despite advances in treatment, the prognosis for patients with pulmonary arterial hypertension (PAH) remains dismal, highlighting the need for further therapeutic advances. By using RNA sequencing on pulmonary artery smooth muscle cells (PASMCs), functional enrichment, and connectivity map analyses, we identify Aurora kinase B (AURKB) as a candidate therapeutic target. We show that AURKB inhibition blocks cell cycle progression and reverses the gene signature of PAH-PASMCs. We also report that PAH-PASMCs that escape apoptosis acquire a senescence-associated secretory phenotype. In vivo, AURKB inhibition using barasertib improves hemodynamics in two preclinical models of established PAH by attenuating pulmonary vascular remodeling. A therapeutic effect is also observed in human precision-cut lung slices. Finally, we demonstrate that the combination of barasertib with a p21 attenuator is more effective in reducing vascular remodeling than either drug alone. These findings provide insight into strategies for therapeutic manipulation.

Pathogenesis of cardiovascular diseases: effects of mitochondrial CF6 on endothelial cell function

Cardiovascular disease (CVD) stands as a predominant global cause of morbidity and mortality, necessitating effective and cost-efficient therapies for cardiovascular risk reduction. Mitochondrial coupling factor 6 (CF6), identified as a novel proatherogenic peptide, emerges as a significant risk factor in endothelial dysfunction development, correlating with CVD severity. CF6 expression can be heightened by CVD risk factors like mechanical force, hypoxia, or high glucose stimuli through the NF-κB pathway. Many studies have explored the CF6-CVD relationship, revealing elevated plasma CF6 levels in essential hypertension, atherosclerotic cardiovascular disease (ASCVD), stroke, and preeclampsia patients. CF6 acts as a vasoactive and proatherogenic peptide in CVD, inducing intracellular acidosis in vascular endothelial cells, inhibiting nitric oxide (NO) and prostacyclin generation, increasing blood pressure, and producing proatherogenic molecules, significantly contributing to CVD development. CF6 induces an imbalance in endothelium-dependent factors, including NO, prostacyclin, and asymmetric dimethylarginine (ADMA), promoting vasoconstriction, vascular remodeling, thrombosis, and insulin resistance, possibly via C-src Ca2+ and PRMT-1/DDAH-2-ADMA-NO pathways. This review offers a comprehensive exploration of CF6 in the context of CVD, providing mechanistic insights into its role in processes impacting CVD, with a focus on CF6 functions, intracellular signaling, and regulatory mechanisms in vascular endothelial cells.

MicroSphere 3D Structures Delay Tissue Senescence through Mechanotransduction

The extracellular matrix (ECM) stores signaling molecules and facilitates mechanical and biochemical signaling in cells. However, the influence of biomimetic "rejuvenation" ECM structures on aging- and degeneration-related cellular activities and tissue repair is not well understood. We combined physical extrusion and precise "on-off" alternating cross-linking methods to create anisotropic biomaterial microgels (MicroRod and MicroSphere) and explored how they regulate the cell activities of the nucleus pulposus (NP) and their potential antidegenerative effects on intervertebral discs. NP cells exhibited aligned growth along the surface of the MicroRod, enhanced proliferation, and reduced apoptosis. This suggests an adaptive cellular response involving adhesion and mechanosensing, which causes cytoskeletal extension via environmental cues. NP cells maintain nuclear membrane integrity through the YAP/TAZ pathway, which activates the cGAS-STING pathway to rectify the aging mechanisms. In vivo, MicroRod carries NP cells and reduces inflammatory factor and protease secretion in degenerated intervertebral discs, inhibiting degeneration and promoting NP tissue regeneration. Our findings highlight the role of mechanical stress in maintaining cellular activity and antiaging effects in harsh environments, providing a foundation for further research and development of antidegenerative biomaterials.

Endothelial FUNDC1 Deficiency Drives Pulmonary Hypertension

BACKGROUND

Pulmonary hypertension (PH) is associated with endothelial dysfunction. However, the cause of endothelial dysfunction and its impact on PH remain incompletely understood. We aimed to investigate whether the hypoxia-inducible FUNDC1 (FUN14 domain-containing 1)-dependent mitophagy pathway underlies PH pathogenesis and progression.

METHODS

We first analyzed FUNDC1 protein levels in lung samples from patients with PH and animal models. Using rodent PH models induced by HySu (hypoxia+SU5416) or chronic hypoxia, we further investigated PH pathogenesis and development in response to global and cell-type-specific Fundc1 loss/gain-of-function. We also investigated the spontaneous PH in mice with inducible loss of endothelial Fundc1. In addition, histological, metabolic, and transcriptomic studies were performed to delineate molecular mechanisms. Finally, findings were validated in vivo by compound deficiency of HIF2α (hypoxia-inducible factor 2α; Epas1) and pharmacological intervention.

RESULTS

FUNDC1 protein levels were reduced in PH lung vessels from clinical subjects and animal models. Global Fundc1 deficiency exacerbated PH, while its overexpression was protective. The effect of FUNDC1 was mediated by endothelial cells rather than smooth muscle cells. Further, inducible loss of endothelial Fundc1 in postnatal mice was sufficient to cause PH spontaneously, whereas augmenting endothelial Fundc1 protected against PH before and after the onset of disease. Mechanistically, Fundc1 deficiency impaired basal mitophagy in endothelial cells, leading to the accumulation of dysfunctional mitochondria, metabolic reprogramming toward aerobic glycolysis, pseudohypoxia, and senescence, likely via a mtROS-HIF2α signaling pathway. Subsequently, Fundc1-deficient endothelial cells increased IGFBP2 (insulin-like growth factor-binding protein 2) secretion that drove pulmonary arterial remodeling to instigate PH. Finally, proof-of-principle in vivo studies showed significant efficacy on PH amelioration by targeting endothelial mitophagy, pseudohypoxia, senescence, or IGFBP2.

CONCLUSIONS

Collectively, we show that FUNDC1-mediated basal mitophagy is critical for endothelial homeostasis, and its disruption instigates PH pathogenesis. Given that similar changes in FUNDC1 and IGFBP2 were observed in PH patients, our findings are of significant clinical relevance and provide novel therapeutic strategies for PH.

Cellular senescence as a source of chronic microinflammation that promotes the aging process

Why and how do we age? This physiological phenomenon that we all experience remains a great mystery, largely unexplained even in this age of scientific and technological progress. Aging is a significant risk factor for numerous diseases, including cancer. However, underlying mechanisms responsible for this association remain to be elucidated. Recent findings have elucidated the significance of the accumulation of senescent cells and other inflammatory cells in organs and tissues with age, and their deleterious effects, such as the induction of inflammation in the microenvironment, as underlying factors contributing to organ dysfunction and disease development. Cellular senescence is a cellular phenomenon characterized by a permanent cessation of cell proliferation and secretion of several proinflammatory cytokines (senescence associated secretory phenotypes). Notably, the elimination of senescent cells from aging individuals has been demonstrated to alleviate age-related organ and tissue dysfunction, as well as various geriatric diseases. This review summarizes the molecular mechanisms by which senescent cells are induced and contribute to age-related diseases, as well as the technologies that ameliorate them.

Exploring Novel Therapeutics for Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by progressive obliteration of pulmonary arteries. Dysregulated bone morphogenetic protein (BMP) signaling pathway contributes to the development of PAH, and pulmonary vasodilators including endothelin receptor antagonists, phosphodiesterase 5 inhibitors, prostaglandins and soluble guanylate cyclase stimulators, dramatically improve the long-term prognosis. However, there still exist refractory patients who require continuous catecholamine support or lung transplantation, and the development of new treatment strategies targeting molecular mechanisms of PAH is highly anticipated. Sotatercept, a first-in-class activin signaling inhibitor, has recently been approved for the treatment of PAH, and it targets and restores an imbalance in activin-growth differentiation factor and BMP pathway signaling. In addition, treatment strategies targeting peroxisome proliferator-activated receptor-γ signaling, inflammatory and immune systems, DNA damage response and cellular senescence, and growth factor receptors including vascular endothelial growth factor and platelet-derived growth factor receptors, are being devised. In this review, we briefly summarize the recent advances in basic research paving the way for the development of more effective treatments for PAH and their potential in clinical therapeutic applications.

Identifying specific functional roles for senescence across cell types

Cellular senescence plays critical roles in aging, regeneration, and disease; yet, the ability to discern its contributions across various cell types to these biological processes remains limited. In this study, we generated an in vivo genetic toolbox consisting of three p16Ink4a-related intersectional genetic systems, enabling pulse-chase tracing (Sn-pTracer), Cre-based tracing and ablation (Sn-cTracer), and gene manipulation combined with tracing (Sn-gTracer) of defined p16Ink4a+ cell types. Using liver injury and repair as an example, we found that macrophages and endothelial cells (ECs) represent distinct senescent cell populations with different fates and functions during liver fibrosis and repair. Notably, clearance of p16Ink4a+ macrophages significantly mitigates hepatocellular damage, whereas eliminating p16Ink4a+ ECs aggravates liver injury. Additionally, targeted reprogramming of p16Ink4a+ ECs through Kdr overexpression markedly reduces liver fibrosis. This study illuminates the functional diversity of p16Ink4a+ cells and offers insights for developing cell-type-specific senolytic therapies in the future.

Drug delivery for age-related bone diseases: From therapeutic targets to common and emerging therapeutic strategies

With the accumulation of knowledge on aging, people have gradually realized that among the many factors that cause individual aging, the accumulation of aging cells is an essential cause of organ degeneration and, ultimately, age-related diseases. Most cells present in the bone microenvironment gradually age over time, leading to an imbalance of osteogenesis, osteoclastogenesis, adipogenesis, and chondrogenesis. This imbalance contributes to age-related bone loss and the development of age-related bone diseases, such as osteoporosis. Bone aging can prolong the lifespan and delay the development of age-related diseases. Nanoparticles have controllable and stable physical and chemical properties and can precisely target different tissues and organs. By preparing multiple easily modified and biocompatible nanoparticles as different drug delivery carriers, specifically targeting various diseased tissues for controlled-release and sustained-release administration, the delivery efficiency of drugs can be significantly improved, and the toxicity and side effects of drugs can be substantially reduced, thereby improving the therapeutic effect of age-related bone diseases. In addition, other novel anti-aging strategies (such as stem cell exosomes) also have significant scientific and practical significance in anti-aging research on age-related bone diseases. This article reviews the research progress of various nano-drug-loaded particles and emerging anti-aging methods for treating age-related bone diseases, offering new insights and directions for precise targeted clinical therapies.

Panorama of artery endothelial cell dysfunction in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a fatal lung disease characterized by progressive pulmonary vascular remodeling. The initial cause of pulmonary vascular remodeling is the dysfunction of pulmonary arterial endothelial cells (PAECs), manifested by changes in the categorization of cell subtypes, endothelial programmed cell death, such as apoptosis, necroptosis, pyroptosis, ferroptosis, et al., overproliferation, senescence, metabolic reprogramming, endothelial-to-mesenchymal transition, mechanosensitivity, and regulation ability of peripheral cells. Therefore, it is essential to explore the mechanism of endothelial dysfunction in the context of PAH. This review aims to provide a comprehensive understanding of the molecular mechanisms underlying endothelial dysfunction in PAH. We highlight the developmental process of PAECs and changes in PAH and summarise the latest classification of endothelial dysfunction. Our review could offer valuable insights into potential novel EC-specific targets for preventing and treating PAH.

Decoding senescence of aging single cells at the nexus of biomaterials, microfluidics, and spatial omics

Aging has profound effects on the body, most notably an increase in the prevalence of several diseases. An important aging hallmark is the presence of senescent cells that no longer multiply nor die off properly. Another characteristic is an altered immune system that fails to properly self-surveil. In this multi-player aging process, cellular senescence induces a change in the secretory phenotype, known as senescence-associated secretory phenotype (SASP), of many cells with the intention of recruiting immune cells to accelerate the clearance of these damaged senescent cells. However, the SASP phenotype results in inducing secondary senescence of nearby cells, resulting in those cells becoming senescent, and improper immune activation resulting in a state of chronic inflammation, called inflammaging, in many diseases. Senescence in immune cells, termed immunosenescence, results in further dysregulation of the immune system. An interdisciplinary approach is needed to physiologically assess aging changes of the immune system at the cellular and tissue level. Thus, the intersection of biomaterials, microfluidics, and spatial omics has great potential to collectively model aging and immunosenescence. Each of these approaches mimics unique aspects of the body undergoes as a part of aging. This perspective highlights the key aspects of how biomaterials provide non-cellular cues to cell aging, microfluidics recapitulate flow-induced and multi-cellular dynamics, and spatial omics analyses dissect the coordination of several biomarkers of senescence as a function of cell interactions in distinct tissue environments. An overview of how senescence and immune dysregulation play a role in organ aging, cancer, wound healing, Alzheimer's, and osteoporosis is included. To illuminate the societal impact of aging, an increasing trend in anti-senescence and anti-aging interventions, including pharmacological interventions, medical procedures, and lifestyle changes is discussed, including further context of senescence.

Aging, ROS, and cellular senescence: a trilogy in the progression of liver fibrosis

Ageing is an inevitable and multifaceted biological process that impacts a wide range of cellular and molecular mechanisms, leading to the development of various diseases, such as liver fibrosis. Liver fibrosis progresses to cirrhosis, which is an advanced form due to high amounts of extracellular matrix and restoration of normal liver structure with failure to repair damaged tissue and cells, marking the end of liver function and total liver failure, ultimately death. The most important factors are reactive oxygen species (ROS) and cellular senescence. Oxidative stress is defined as an impairment by ROS, which are by-products of the mitochondrial electron transport chain and other key molecular pathways that induce cell damage and can activate cellular senescence pathways. Cellular senescence is characterized by pro-inflammatory cytokines, growth factors, and proteases secreted by senescent cells, collectively known as the senescence-associated secretory phenotype (SASP). The presence of senescent cells, which disrupt tissue architecture and function and increase senescent cell production in liver tissues, contributes to fibrogenesis. Hepatic stellate cells (HSCs) are activated in response to chronic liver injury, oxidative stress, and senescence signals that drive excessive production and deposition of extracellular matrix. This review article aims to provide a comprehensive overview of the pathogenic role of ROS and cellular senescence in the aging liver and their contribution to fibrosis.

A signaling pathway map of plasminogen activator inhibitor-1 (PAI-1/SERPINE-1): a review of an innovative frontier in molecular aging and cellular senescence

Plasminogen activator inhibitor-1 (PAI-1) is a vital regulator of the fibrinolytic mechanism and has been intricately involved in various physiological and clinical processes, including cancer, thrombosis, and wound healing. The PAI-1 signaling pathway is multifaceted, encompassing numerous signaling molecules and nodes. Recent studies have revealed a novel contribution of PAI-1 during cellular senescence. This review introduces a pathway resource detailing the signaling network events mediated by PAI-1. The literature curated on the PAI-1 system was manually compiled from various published studies, our analysis presents a signaling pathway network of PAI-1, which includes various events like enzyme catalysis, molecular association, gene regulation, protein expression, and protein translocation. This signaling network aims to provide a detailed analysis of the existing understanding of the PAI-1 signaling pathway in the context of cellular senescence across various research models. By developing this pathway, we aspire to deepen our understanding of aging and senescence research, ultimately contributing to the pursuit of effective therapeutic approaches for these complex chronic diseases.

Cell senescence in cardiometabolic diseases

Cellular senescence has been implicated in many age-related pathologies including atherosclerosis, heart failure, age-related cardiac remodeling, diabetic cardiomyopathy and the metabolic syndrome. Here, we will review the characteristics of senescent cells and their endogenous regulators, and summarize the metabolic stressors that induce cell senescence. We will discuss the evidence of cell senescence in the onset and progression of several cardiometabolic diseases and the therapeutic potential of anti-senescence therapies.

Unraveling the role of HIF and epigenetic regulation in pulmonary arterial hypertension: implications for clinical research and its therapeutic approach

Pulmonary arterial hypertension (PAH) is characterized by pulmonary vascular remodeling with high pulmonary pressure, which ultimately leads to right heart failure and premature death. Emerging evidence suggests that both hypoxia and epigenetics play a pivotal role in the pathogenesis of PAH development. In this review article, we summarize the current developments in regulation of hypoxia inducible factor (HIF) isoforms in PAH vascular remodeling and the development of suitable animal models for discovery and testing of HIF pathway-targeting PAH therapeutics. In addition, we also discuss the epigenetic regulation of HIF-dependent isoforms in PAH and its therapeutic potential from a new perspective which highlights the importance of HIF isoform-specific targeting as a novel salutary strategy for PAH treatment.

Aging in chronic lung disease: Will anti-aging therapy be the key to the cure?

Chronic lung disease is the third leading cause of death globally, imposing huge burden of death, disability and healthcare costs. However, traditional pharmacotherapy has relatively limited effects in improving the cure rate and reducing the mortality of chronic lung disease. Thus, new treatments are urgently needed for the prevention and treatment of chronic lung disease. It is particularly noteworthy that, multiple aging-related phenotypes were involved in the occurrence and development of chronic lung disease, such as blocked proliferation, telomere attrition, mitochondrial dysfunction, epigenetic alterations, altered nutrient perception, stem cell exhaustion, chronic inflammation, etc. Consequently, senescent cells induce a series of pathological changes in the lung, such as immune dysfunction, airway remodeling, oxidative stress and regenerative dysfunction, which is a critical issue that needs special attention in chronic lung diseases. Therefore, anti-aging interventions may bring new insights into the treatment of chronic lung diseases. In this review, we elaborate the involvement of aging in chronic lung disease and further discuss the application and prospects of anti-aging therapy.

Uncovering key mechanisms and intervention therapies in aging skin

Advancements in understanding skin aging mechanisms, which encompass both external and internal aging processes, have spurred the development of innovative treatments primarily aimed at improving cosmetic appearance. These findings offer the potential for the development of novel therapeutic strategies aimed at achieving long-term, non-therapy-dependent clinical benefits, including the reversal of aging and the mitigation of associated health conditions. Realizing this goal requires further research to establish the safety and efficacy of targeting aging-related skin changes, such as pigmentation, wrinkling, and collagen loss. Systematic investigation is needed to identify the most effective interventions and determine optimal anti-aging treatment strategies. These reviews highlight the features and possible mechanisms of skin aging, as well as the latest progress and future direction of skin aging research, to provide a theoretical basis for new practical anti-skin aging strategies.

Pathology and pathobiology of pulmonary hypertension: current insights and future directions

In recent years, major advances have been made in the understanding of the cellular and molecular mechanisms driving pulmonary vascular remodelling in various forms of pulmonary hypertension, including pulmonary arterial hypertension, pulmonary hypertension associated with left heart disease, pulmonary hypertension associated with chronic lung disease and hypoxia, and chronic thromboembolic pulmonary hypertension. However, the survival rates for these different forms of pulmonary hypertension remain unsatisfactory, underscoring the crucial need to more effectively translate innovative scientific knowledge into healthcare interventions. In these proceedings of the 7th World Symposium on Pulmonary Hypertension, we delve into recent developments in the field of pathology and pathophysiology, prioritising them while questioning their relevance to different subsets of pulmonary hypertension. In addition, we explore how the latest omics and other technological advances can help us better and more rapidly understand the myriad basic mechanisms contributing to the initiation and progression of pulmonary vascular remodelling. Finally, we discuss strategies aimed at improving patient care, optimising drug development, and providing essential support to advance research in this field.

Identification and experimental verification of senescence-related gene signatures and molecular subtypes in idiopathic pulmonary arterial hypertension

Evidences illustrate that cell senescence contributes to the development of pulmonary arterial hypertension. However, the molecular mechanisms remain unclear. Since there may be different senescence subtypes between PAH patients, consistent senescence-related genes (SRGs) were utilized for consistent clustering by unsupervised clustering methods. Senescence is inextricably linked to the immune system, and the immune cells in each cluster were estimated by ssGSEA. To further screen out more important SRGs, machine learning algorithms were used for identification and their diagnostic value was assessed by ROC curves. The expression of hub genes were verified in vivo and in vitro. Transcriptome analysis was used to assess the effects of silence of hub gene on different pathways. Three senescence molecular subtypes were identified by consensus clustering. Compared with cluster A and B, most immune cells and checkpoint genes were higher in cluster C. Thus, we identified senescence cluster C as the immune subtype. The ROC curves of IGF1, HOXB7, and YWHAZ were remarkable in both datasets. The expression of these genes was increased in vitro. Western blot and immunohistochemical analyses revealed that YWHAZ expression was also increased. Our transcriptome analysis showed autophagy-related genes were significantly elevated after silence of YWHAZ. Our research provided several prospective SRGs and molecular subtypes. Silence of YWHAZ may contribute to the clearance of senescent endothelial cells by activating autophagy.

TG2 participates in pulmonary vascular remodelling by regulating the senescence of pulmonary artery smooth muscle cells

Pulmonary hypertension (PH) is a severe cardiovascular disease characterised by pulmonary vascular remodelling. The pivotal role of cellular senescence in vascular remodelling has been acknowledged. Transglutaminase type 2 (TG2), a calcium-dependent enzyme, is intricately linked to both cellular senescence and PH. However, the precise mechanisms underlying the involvement of TG2 in PH remain unclear. In this study, we explored the expression of TG2 and the cellular senescence marker p16INK4a in the pulmonary vasculature of mice with PH induced by hypoxia combined with SU5416. Our findings revealed upregulation of both TG2 and p16INK4a expression in the pulmonary vasculature of PH mice. Additionally, a notable increase in TG2 expression was observed in senescent pulmonary artery smooth muscle cells (PASMC). To delve deeper, we employed proteomic sequencing to reveal seven genes associated with cellular senescence, with a subsequent focus on MAPK14. Our investigation revealed that TG2 regulates senescence in PASMC by modulating the phosphorylation levels of MAPK14. Additionally, in the context of hypoxia combined with SU5416, our observations revealed a noteworthy reduction in both pulmonary vascular remodelling and senescent manifestations in smooth muscle-specific TG2 knockout mice compared with their wild-type counterparts. In summary, our findings indicate that TG2 deficiency lowers the senescence levels of PASMC by inhibiting the activity of MAPK14. This inhibition of senescence in the pulmonary vasculature of PH mice helps to decelerate the progression of pulmonary vascular remodelling and consequently hinders the onset and development of PH.

Loss of Nup155 promotes high fructose-driven podocyte senescence by inhibiting INO80 mRNA nuclear export

INTRODUCTION

Podocyte senescence causes podocyte loss and glomerulopathy. Excessive fructose intake is a risk factor for podocyte injury. However, whether high fructose promotes podocyte senescence remains unknown.

OBJECTIVES

To explore the pathological mechanism by which high fructose drives podocyte senescence and find natural compounds to alleviate podocyte senescence.

METHODS

Podocyte senescence was characterized with senescence-associated beta-galactosidase (SA-β-gal) staining, Western blot, real-time quantitative polymerase chain reaction (qRT-PCR), comet assay and immunofluorescence. Proteomics analysis was performed to identify differentially expressed proteins in high fructose-exposed podocytes. Podocyte nuclear pore complexes (NPCs) and foot processes were observed by transmission electron microscopy. The mRNA and protein levels of nucleoporin 155 (Nup155) and inositol requiring mutant 80 (INO80) were detected by qRT-PCR, Western blot and immunofluorescence. Virtual screening was conducted to find natural compounds that target Nup155.

RESULTS

High fructose increased SA-β-gal activity, protein level of p53, p21, p16 and phosphorylated histone H2AX (γ-H2AX), as well as mRNA expression of interleukin-1β (IL-1β), IL-6 and tumor necrosis factor α (TNF-α) in rat glomeruli and podocytes. Proteomic analysis unraveled a crucial molecule Nup155, which was decreased in high fructose-induced podocyte senescence. Meanwhile, the number of podocyte NPCs was also decreased in vivo and in vitro. Consistently, high fructose suppressed nuclear export of INO80 mRNA, thereby down-regulated INO80 protein expression in podocyte senescence. Deletion of Nup155 inhibited INO80 mRNA nuclear export to induce podocyte senescence, whereas overexpression of Nup155 or INO80 alleviated high fructose-induced podocyte senescence. Ferulic acid was found to up-regulate Nup155 by both direct binding to stabilize Nup155 protein and enhancing its transcription, to promote INO80 mRNA nuclear export in the mitigation of high fructose-caused podocyte senescence.

CONCLUSION

High fructose induces podocyte senescence by decreasing Nup155 to inhibit INO80 mRNA nuclear export. Ferulic acid targeting Nup155 may be a potential strategy to prevent high fructose-induced podocyte senescence.

Cellular senescence in the pathogenesis of pulmonary arterial hypertension: the good, the bad and the uncertain

Senescence refers to a cellular state marked by irreversible cell cycle arrest and the secretion of pro-inflammatory and tissue-remodeling factors. The senescence associated secretory phenotype (SASP) impacts the tissue microenvironment and provides cues for the immune system to eliminate senescent cells (SCs). Cellular senescence has a dual nature; it can be beneficial during embryonic development, tissue repair, and tumor suppression, but it can also be detrimental in the context of chronic stress, persistent tissue injury, together with an impairment in SC clearance. Recently, the accumulation of SCs has been implicated in the pathogenesis of pulmonary arterial hypertension (PAH), a progressive condition affecting the pre-capillary pulmonary arterial bed. PAH is characterized by endothelial cell (EC) injury, inflammation, and proliferative arterial remodeling, which leads to right heart failure and premature mortality. While vasodilator therapies can improve symptoms, there are currently no approved treatments capable of reversing the obliterative arterial remodeling. Ongoing endothelial injury and dysfunction is central to the development of PAH, perpetuated by hemodynamic perturbation leading to pathological intimal shear stress. The precise role of senescent ECs in PAH remains unclear. Cellular senescence may facilitate endothelial repair, particularly in the early stages of disease. However, in more advanced disease the accumulation of senescent ECs may promote vascular inflammation and occlusive arterial remodeling. In this review, we will examine the evidence that supports a role of endothelial cell senescence to the pathogenesis of PAH. Furthermore, we will compare and discuss the apparent contradictory outcomes with the use of interventions targeting cellular senescence in the context of experimental models of pulmonary hypertension. Finally, we will attempt to propose a framework for the understanding of the complex interplay between EC injury, senescence, inflammation and arterial remodeling, which can guide further research in this area and the development of effective therapeutic strategies.

Quercetin induces senolysis of doxorubicin-induced senescent fibroblasts by reducing autophagy, preventing their pro-tumour effect on osteosarcoma cells

Cellular senescence contributes to ageing and age-related diseases, and multiple therapeutic strategies are being developed to counteract it. Senolytic drugs are being tested in clinical trials to eliminate senescent cells selectively, but their effects and mechanisms are still unclear. Several studies reveal that the upregulation of senescence-associated secretory phenotype (SASP) factors in senescent cells is accompanied by increased autophagic activity to counteract the endoplasmic reticulum (ER) stress. Our study shows that Doxo-induced senescent fibroblasts yield several SASP factors and exhibit increased autophagy. Interestingly, Quercetin, a bioactive flavonoid, reduces autophagy, increases ER stress, and partially triggers senescent fibroblast death. Given the role of senescent cells in cancer progression, we tested the effect of conditioned media from untreated and quercetin-treated senescent fibroblasts on osteosarcoma cells to determine whether senolytic treatment affected tumour cell behaviour. We report that the partial senescent fibroblast clearance, achieved by quercetin, reduced osteosarcoma cell invasiveness, curbing the pro-tumour effects of senescent cells. The reduction of cell autophagic activity and increased ER stress, an undescribed effect of quercetin, emerges as a new vulnerability of Doxo-induced senescent fibroblasts and may provide a potential therapeutic target for cancer treatment, suggesting novel drug combinations as a promising strategy against the tumour.

Nur77 improves ovarian function in reproductive aging mice by activating mitophagy and inhibiting apoptosis

Reproductive aging not only affects the fertility and physical and mental health of women but also accelerates the aging process of other organs. There is an urgent need newfor novel mechanisms, targets, and drugs to break the vicious cycle of mitochondrial dysfunction, redox imbalance, and germ cell apoptosis associated with ovarian aging. Autophagy, recognized as a longevity mechanism, has recently become a focal point in anti-aging research. Although mitophagy is a type of autophagy, its role and regulatory mechanisms in ovarian aging, particularly in age-related ovarian function decline, remain unclear. Nerve growth factor inducible gene B (Nur77) is an early response gene that can be stimulated by oxidative stress, DNA damage, metabolism, and inflammation. Recent evidence recommends that decreased expression of Nur77 is associated with age-related myocardial fibrosis, renal dysfunction, and Parkinson's disease; however, its association with ovarian aging has not been studied yet. We herein identified Nur77 as a regulator of germ cell senescence, apoptosis, and mitophagy and found that overexpression of Nur77 can activate mitophagy, improve oxidative stress, reduce apoptosis, and ultimately enhance ovarian reserve in aged mice ovaries. Furthermore, we discovered an association between Nur77 and the AKT pathway through String and molecular docking analyses. Experimental confirmation revealed that the AKT/mTOR signaling pathway is involved in the regulation of Nur77 in ovarian function. In conclusion, our results suggest Nur77 as a promising target for preventing and treating ovarian function decline related to reproductive aging.

p16High immune cell - controlled disease tolerance as a broad defense and healthspan extending strategy

The ability of an organism to overcome infectious diseases has traditionally been linked to killing invading pathogens. Accumulating evidence, however, indicates that, apart from restricting pathogen loads, organismal survival is coupled to an additional yet poorly understood mechanism called disease tolerance. Here we report that p16High immune cells play a key role in establishing disease tolerance. We found that the FDA-approved BNT162b2 mRNA COVID-19 vaccine is a potent and rapid inducer of p16High immune subsets both in mice and humans. In turn, p16High immune cells were indispensable for counteracting different lethal conditions, including LPS-induced sepsis, acute SARS-CoV-2 infection and ionizing irradiation. Mechanistically, we propose that activation of TLR7 or a low physiological activity of STING is sufficient to induce p16High immune subset that, in turn, establishes a low adenosine environment and disease tolerance. Furthermore, containing these signals within a beneficial range by deleting MDA5 that appeared sufficient to maintain a low activity of STING, induces p16High immune cells and delays organ deterioration upon aging with improved healthspan. Our data highlight the beneficial role of p16High immune subsets in establishing a low adenosine environment and disease tolerance.

Procyanidin C1 inhibits bleomycin-induced pulmonary fibrosis in mice by selective clearance of senescent myofibroblasts

Pulmonary fibrosis is a formidable challenge in chronic and age-related lung diseases. Myofibroblasts secrete large amounts of extracellular matrix and induce pro-repair responses during normal wound healing. Successful tissue repair results in termination of myofibroblast activity via apoptosis; however, some myofibroblasts exhibit a senescent phenotype and escape apoptosis, causing over-repair that is characterized by pathological fibrotic scarring. Therefore, the removal of senescent myofibroblasts using senolytics is an important method for the treatment of pulmonary fibrosis. Procyanidin C1 (PCC1) has recently been discovered as a senolytic compound with very low toxicity and few side effects. This study aimed to determine whether PCC1 could improve lung fibrosis by promoting apoptosis in senescent myofibroblasts and to investigate the mechanisms involved. The results showed that PCC1 attenuates bleomycin (BLM)-induced pulmonary fibrosis in mice. In addition, we found that PCC1 inhibited extracellular matrix deposition and promoted the apoptosis of senescent myofibroblasts by increasing PUMA expression and activating the BAX signaling pathway. Our findings represent a new method of pulmonary fibrosis management and emphasize the potential of PCC1 as a senotherapeutic agent for the treatment of pulmonary fibrosis, providing hope for patients with pulmonary fibrosis worldwide. Our results advance our understanding of age-related diseases and highlight the importance of addressing cellular senescence in treatment.

LILRB2 inhibition enhances radiation sensitivity in non-small cell lung cancer by attenuating radiation-induced senescence

Radiotherapy (RT) in non-small cell lung cancer (NSCLC) triggers cellular senescence, complicating tumor microenvironments and affecting treatment outcomes. This study examines the role of lymphocyte immunoglobulin-like receptor B2 (LILRB2) in modulating RT-induced senescence and radiosensitivity in NSCLC. Through methodologies including irradiation, lentivirus transfection, and various molecular assays, we assessed LILRB2's expression and its impact on cellular senescence levels and tumor cell behaviors. Our findings reveal that RT upregulates LILRB2, facilitating senescence and a senescence-associated secretory phenotype (SASP), which in turn enhances tumor proliferation and resistance to radiation. Importantly, LILRB2 silencing attenuates these effects by inhibiting the JAK2/STAT3 pathway, significantly increasing radiosensitivity in NSCLC models. Clinical data correlate high LILRB2 expression with reduced RT response and poorer prognosis, suggesting LILRB2's pivotal role in RT-induced senescence and its potential as a therapeutic target to improve NSCLC radiosensitivity.

Cellular senescence in normal physiology

Long associated with aging, senescent cells can promote health and have physiological roles.

PGC1α-Inducing Senomorphic Nanotherapeutics Functionalized with NKG2D-Overexpressing Cell Membranes for Intervertebral Disc Degeneration

Cellular senescence is a significant contributor to intervertebral disc aging and degeneration. However, the application of senotherapies, such as senomorphics targeting senescence markers and the senescence-associated secretory phenotype (SASP), remains limited due to challenges in precise delivery. Given that the natural killer group 2D (NKG2D) ligands are increased on the surface of senescent nucleus pulposus (NP) cells, the NKG2D-overexpressing NP cell membranes (NNPm) are constructed, which is expected to achieve a dual targeting effect toward senescent NP cells based on homologous membrane fusion and the NKG2D-mediated immunosurveillance mechanism. Then, mesoporous silica nanoparticles carrying a peroxisome proliferator-activated receptor-ɣ coactivator 1α (PGC1α)inducer (SP) are coated with NNPm (SP@NNPm) and it is found that SP@NNPm selectively targets senescent NP cells, and the SP cores exhibit pH-responsive drug release. Moreover, SP@NNPm effectively induces PGC1α-mediated mitochondrial biogenesis and mitigates senescence-associated markers induced by oxidative stress and the SASP, thereby alleviating puncture-induced senescence and disc degeneration. This dual-targeting nanotherapeutic system represents a novel approach to delivery senomorphics for disc degeneration treatment.

Cellular senescence in acute kidney injury: Target and opportunity

Acute kidney injury (AKI) is a common clinical disease with a high incidence and mortality rate. It typically arises from hemodynamic alterations, sepsis, contrast agents, and toxic drugs, instigating a series of events that culminate in tissue and renal damage. This sequence of processes often leads to acute renal impairment, prompting the initiation of a repair response. Cellular senescence is an irreversible arrest of the cell cycle. Studies have shown that renal cellular senescence is closely associated with AKI through several mechanisms, including the promotion of oxidative stress and inflammatory response, telomere shortening, and the down-regulation of klotho expression. Exploring the role of cellular senescence in AKI provides innovative therapeutic ideas for both the prevention and treatment of AKI. Furthermore, it has been observed that targeted removal of senescent cells in vivo can efficiently postpone senescence, resulting in an enhanced prognosis for diseases associated with senescence. This article explores the effects of common anti-senescence drugs senolytics and senostatic and lifestyle interventions on renal diseases, and mentions the rapid development of mesenchymal stem cells (MSCs). These studies have taken senescence-related research to a new level. Overall, this article comprehensively summarizes the studies on cellular senescence in AKI, aiming is to elucidate the relationship between cellular senescence and AKI, and explore treatment strategies to improve the prognosis of AKI.

Targeting vascular senescence in cardiovascular disease with aging

Aging is a major risk factor for atherosclerosis and cardiovascular disease (CVD). Two major age-associated arterial phenotypes, endothelial dysfunction and large elastic arterial stiffness, are autonomous predictors of future CVD diagnosis and contribute to the progression of CVD in older adults. Senescent cells lose the capacity to proliferate but remain metabolically active and secrete inflammatory factors termed senescence-associated secretory phenotype (SASP), leading to an increase in inflammation and oxidative stress. Accumulation of senescent cells is linked with the progression of age-related diseases and has been known to play a role in cardiovascular disease. In this brief review, we describe the characteristics and mechanisms of senescent cell accumulation and how senescent cells promote endothelial dysfunction and arterial stiffness. We focus on a range of novel therapeutic strategies aimed at reducing the burden of endothelial dysfunction leading to atherosclerosis through targeting senescent cells. Studies have begun to investigate a specific class of drugs that are able to selectively eliminate senescent cells, termed senolytics, which have shown great promise in reversing the aging phenotype and ameliorating pathologies in age-related disorders, creating a new opportunity for aging research. Generating therapies targeting the elimination of senescent cells would improve health span and increase longevity, making senolytics a promising therapy for cardiovascular diseases.

Accelerated Aging in Cancer Survivors: Cellular Senescence, Frailty, and Possible Opportunities for Interventions

The population of cancer survivors has markedly increased due to the rapid improvements in cancer treatment. However, cancer survivors experience accelerated aging, which leads to chronic diseases and other age-related conditions, such as frailty. Those conditions may persist years after cancer diagnosis and treatment. Cellular senescence, a hallmark of aging, is one of the mechanisms that contribute to accelerated aging in cancer survivors. Several aging measures, including measures based on clinical markers and biomarkers, have been proposed to estimate the aging process, and some of them have shown associations with mortality and frailty in cancer survivors. Several anti-aging interventions, including lifestyle changes and anti-aging drugs, have been proposed. Future research, particularly in large-scale studies, is needed to determine the efficiency of these aging measures and anti-aging interventions before considering their application in clinics. This review focuses on the mechanisms of cellular senescence and accelerated aging in cancer survivors, assessment of the aging process using clinical markers and biomarkers, and the high prevalence of frailty in that population, as well as possible opportunities for anti-aging interventions. A deeper understanding of aging measures and anti-aging interventions in cancer survivors will contribute to the development of effective strategies to mitigate accelerated aging in cancer survivors and improve their quality of life.

Senescent T Cells in Age-Related Diseases

Age-induced alterations in human immunity are often considered deleterious and are referred to as immunosenescence. The immune system monitors the number of senescent cells in the body, while immunosenescence may represent the initiation of systemic aging. Immune cells, particularly T cells, are the most impacted and involved in age-related immune function deterioration, making older individuals more prone to different age-related diseases. T-cell senescence can impact the effectiveness of immunotherapies that rely on the immune system's function, including vaccines and adoptive T-cell therapies. The research and practice of using senescent T cells as therapeutic targets to intervene in age-related diseases are in their nascent stages. Therefore, in this review, we summarize recent related literature to investigate the characteristics of senescent T cells as well as their formation mechanisms, relationship with various aging-related diseases, and means of intervention. The primary objective of this article is to explore the prospects and possibilities of therapeutically targeting senescent T cells, serving as a valuable resource for the development of immunotherapy and treatment of age-related diseases.

Targeting cellular senescence: A promising approach in respiratory diseases

Cellular senescence serves as a significant tumor suppression mechanism in mammals. Cellular senescence is induced in response to various stressors and acts as a safeguard against the uncontrolled proliferation of damaged cells that could lead to malignant transformation. Senescent cells also exhibit a distinctive feature known as the senescence-associated secretory phenotype (SASP), wherein they secrete a range of bioactive molecules, including pro-inflammatory cytokines, growth factors, and proteases. These SASP components have both local and systemic effects, influencing the surrounding microenvironment and distant tissues, and have been implicated in the processes of tissue aging and the development of chronic diseases. Recent studies utilizing senolysis models have shed light on the potential therapeutic implications of targeting senescent cells. The targeting of senescent cell may alleviate the detrimental effects associated with cellular senescence and its SASP components. Senolytics have shown promise in preclinical studies for treating age-related pathologies and chronic diseases, including cancer, cardiovascular disorders, and neurodegenerative conditions. Respiratory diseases have emerged as a significant global health concern, responsible for a considerable number of deaths worldwide. Extensive research conducted in both human subjects and animal models has demonstrated the involvement of cellular senescence in the pathogenesis of respiratory diseases. Chronic pulmonary conditions such as chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis have been linked to the accumulation of senescent cells. This review aims to present the findings from research on respiratory diseases that have utilized systems targeting senescent cells and to identify potential therapeutic strategies for the clinical management of these conditions. Geriatr Gerontol Int 2024; 24: 60-66.

mTert induction in p21-positive cells counteracts capillary rarefaction and pulmonary emphysema

Lung diseases develop when telomeres shorten beyond a critical point. We constructed a mouse model in which the catalytic subunit of telomerase (mTert), or its catalytically inactive form (mTertCI), is expressed from the p21Cdkn1a locus. Expression of either TERT or TERTCI reduces global p21 levels in the lungs of aged mice, highlighting TERT non-canonical function. However, only TERT reduces accumulation of very short telomeres, oxidative damage, endothelial cell (ECs) senescence and senile emphysema in aged mice. Single-cell analysis of the lung reveals that p21 (and hence TERT) is expressed mainly in the capillary ECs. We report that a fraction of capillary ECs marked by CD34 and endowed with proliferative capacity declines drastically with age, and this is counteracted by TERT but not TERTCI. Consistently, only TERT counteracts decline of capillary density. Natural aging effects are confirmed using the experimental model of emphysema induced by VEGFR2 inhibition and chronic hypoxia. We conclude that catalytically active TERT prevents exhaustion of the putative CD34 + EC progenitors with age, thus protecting against capillary vessel loss and pulmonary emphysema.

Therapy-induced senescence is finally escapable, what is next?

Several breakthrough articles have recently confirmed the ability of tumor cells to escape the stable cell cycle arrest imposed by Therapy-Induced Senescence (TIS). Subsequently, accepting the hypothesis that TIS is escapable should encourage serious reassessments of the fundamental roles of senescence in cancer treatment. The potential for escape from TIS undermines the well-established tumor suppressor function of senescence, proposes it as a mechanism of tumor dormancy leading to disease recurrence and invites for further investigation of its unfavorable contribution to cancer therapy outcomes. Moreover, escaping TIS strongly indicates that the elimination of senescent tumor cells, primarily through pharmacological means, is a suitable approach for increasing the efficacy of cancer treatment, one that still requires further exploration. This commentary provides an overview of the recent evidence that unequivocally demonstrated the ability of therapy-induced senescent tumor cells in overcoming the terminal growth arrest fate and provides future perspectives on the roles of TIS in tumor biology.

Connecting epigenetics and inflammation in vascular senescence: state of the art, biomarkers and senotherapeutics

Vascular diseases pose major health challenges, and understanding their underlying molecular mechanisms is essential to advance therapeutic interventions. Cellular senescence, a hallmark of aging, is a cellular state characterized by cell-cycle arrest, a senescence-associated secretory phenotype macromolecular damage, and metabolic dysregulation. Vascular senescence has been demonstrated to play a key role in different vascular diseases, such as atherosclerosis, peripheral arterial disease, hypertension, stroke, diabetes, chronic venous disease, and venous ulcers. Even though cellular senescence was first described in 1961, significant gaps persist in comprehending the epigenetic mechanisms driving vascular senescence and its subsequent inflammatory response. Through a comprehensive analysis, we aim to elucidate these knowledge gaps by exploring the network of epigenetic alterations that contribute to vascular senescence. In addition, we describe the consequent inflammatory cascades triggered by these epigenetic modifications. Finally, we explore translational applications involving biomarkers of vascular senescence and the emerging field of senotherapy targeting this biological process.

Mild Uncoupling of Mitochondria Synergistically Enhances Senolytic Specificity and Sensitivity of BH3 Mimetics

Despite immense potential as anti-aging interventions, applications of current senolytics are limited due to low sensitivity and specificity. We demonstrate the specific loss of complex I-linked coupled respiration and the inability to maintain mitochondrial membrane potential upon respiratory stimulation as a specific vulnerability of senescent cells. Further decreasing the mitochondrial membrane potential of senescent cells with a mitochondrial uncoupler synergistically enhances the in vitro senolytic efficacy of BH3 mimetic drugs, including Navitoclax, by up to two orders of magnitude, whereas non-senescent cells remain unaffected. Moreover, a short-term intervention combining the mitochondrial uncoupler BAM15 with Navitoclax at a dose two orders of magnitude lower than typically used rescues radiation-induced premature aging in an in vivo mouse model, as demonstrated by reduced frailty and improved cognitive function for at least eight months. Our study shows compromised mitochondrial functional capacity is a senescence-specific vulnerability that can be targeted by mild uncoupling in vitro and in vivo.

Recent Advancement in Elimination Strategies and Potential Rejuvenation Targets of Senescence

Cellular senescence is a state of exiting the cell cycle, resisting apoptosis, and changing phenotype. Senescent cells (SCs) can be identified by large, distorted morphology and irreversible inability to replicate. In early development, senescence has beneficial roles like tissue patterning and wound healing, where SCs are cleared by the immune system. However, there is a steep rise in SC number as organisms age. The issue with SC accumulation stems from the loss of cellular function, alterations of the microenvironment, and secretions of pro-inflammatory molecules, consisting of cytokines, chemokines, matrix metalloproteinases (MMPs), interleukins, and extracellular matrix (ECM)-associated molecules. This secreted cocktail is referred to as the senescence-associated secretory phenotype (SASP), a hallmark of cellular senescence. The SASP promotes inflammation and displays a bystander effect where paracrine signaling turns proliferating cells into senescent states. To alleviate age-associated diseases, researchers have developed novel methods and techniques to selectively eliminate SCs in aged individuals. Although studies demonstrated that selectively killing SCs improves age-related disorders, there are drawbacks to SC removal. Considering favorable aspects of senescence in the body, this paper reviews recent advancements in elimination strategies and potential rejuvenation targets of senescence to bring researchers in the field up to date.