Vascular Smooth Muscle Cell Senescence Promotes Atherosclerosis and Features of Plaque Vulnerability

STING and metabolism-related diseases: Roles, mechanisms, and applications

The stimulator of interferon genes (STING) pathway plays a critical role in innate immunity, acting as a central mediator that links cytosolic DNA sensing to inflammatory signaling. STING not only responds to cellular metabolic states but also actively regulates key metabolic processes, including glycolysis, lipid metabolism, and redox balance. This bidirectional interaction underscores the existence of a dynamic feedback mechanism between STING signaling and metabolic pathways, which is essential for maintaining cellular homeostasis. This review provides a comprehensive analysis, beginning with an in-depth overview of the classical STING signaling pathway, followed by a detailed examination of its reciprocal regulation of various metabolic pathways. Additionally, it explores the role and mechanisms of STING signaling in metabolic disorders, including obesity, diabetes, and atherosclerosis. By integrating these insights into the mutual regulation between STING and its metabolism, novel therapeutic strategies targeting this pathway in metabolic diseases have been proposed.

Vascular cellular senescence in human atherosclerosis: The critical modulating roles of CDKN2A and CDK4/6 signaling pathways

Vascular cellular senescence promotes vascular aging and atherogenesis. Mitigating vascular cellular senescence serves as a promising therapy for atherosclerosis. Transcriptomic analysis was conducted to reveal the differentially expressed genes (DEGs) regulating cell proliferation, growth, senescence, and death in human atherosclerotic lesions vs. normal vessels. The key DEGs were screened out using Venn diagrams. Ox-LDL induced umbilical vein endothelial cells (HUVECs) and high fat diet-fed ApoE-/- mice were utilized to construct model. We identified CDKN2A as a senescence-related DEG. The upregulated CDKN2A depressed the downstream CDK4/6 in ox-LDL treated HUVECs. Ox-LDL aggravated cell-cycle arrest, decreased cellular viability, inhibited migration, led to flattened and enlarged senescent morphology, generated ROS, and elevated β-galactosidase activity along with increment in β-galactosidase expression, which were ameliorated by CDKN2A knockdown and, conversely, were exacerbated by the addition of CDK4/6 inhibitor palbociclib. β-galactosidase activity and ROS production were significantly elevated in human and mice atherosclerotic lesions. β-galactosidase, co-localized with CD31, was obviously upregulated in atherosclerotic lesions, indicating endothelial cellular senescence in vivo. CDKN2A, co-localized with CD31, was markedly increased in atherosclerotic lesions, indicating the CDKN2A immunopositivity in endothelial cells in vivo. Colocalization of CDKN2A with CDK4/6 revealed the potential connection in vivo. Palbociclib exacerbated vascular cell senescence and atherogenesis in mice. Endothelial cellular senescence is present in atherosclerotic lesions. CDKN2A and CDK4/6 pathway is active in endothelial cellular senescence and atherogenesis, and altering CDKN2A and CDK4/6 pathway plays a critical role in alleviating endothelial cellular senescence and atherosclerosis, implying novel targets for prevention of vascular aging and atherogenesis.

Advancing T-cell immunotherapy for cellular senescence and disease: Mechanisms, challenges, and clinical prospects

Cellular senescence is a complex biological process with a dual role in tissue homeostasis and aging-related pathologies. Accumulation of senescent cells promotes chronic inflammation, tissue dysfunction, age-related diseases, and tumor suppression. Recent advancements in immunotherapy have positioned T cell-based approaches as precision tools for the targeted clearance of senescent cells, offering a novel avenue for anti-aging interventions. This review explores the molecular mechanisms underlying cellular senescence, focusing on its immunogenic features and interactions with T cells, including T-cell activation, antigen recognition, modulation of tumor microenvironment (TME), and immune evasion strategies. Innovations such as chimeric antigen receptor (CAR)-T cells, immune checkpoint therapies, and SASP-neutralizing approaches are highlighted as breakthrough strategies for enhancing senescent cell eradication. The integration of multi-omics and artificial intelligence is further catalyzing the development of personalized therapies to amplify immune surveillance and tissue rejuvenation. Clinically, T cell-based interventions hold promise for mitigating age-related pathologies and extending healthspan, yet challenges remain in optimizing target specificity, countering immunosuppressive niches, and overcoming immune senescence in aging populations. This review synthesizes current advances and challenges, highlighting the potential of T cell immunotherapy as a cornerstone of anti-aging medicine and emphasizing the need for interdisciplinary innovation to translate preclinical findings into transformative therapies for aging and age-related diseases.

Roles of Brd4 in Vascular Smooth Muscle Cells: Implications for Aging and Vascular Dysfunction

BACKGROUND

Growing evidence suggests that the epigenetic reader Brd4 (bromodomain-containing protein 4) is involved in aging and aging-related diseases. However, the specific mechanisms by which Brd4 influences vascular aging, especially senescence of vascular smooth muscle cells (SMCs), remain unexplored.

METHODS

Primary cell cultures were established using mouse aortic SMCs and treated with Brd4 inhibitor, ARV-825, or (+)-JQ1. Primary Brd4flox/flox mouse aortic SMCs were transduced with Ad-Cre virus to induce Brd4 knockout (KO). Senescence was assessed through SA-β-gal (senescence-associated β-galactosidase) staining. A mouse model of inducible SMC-specific Brd4 gene KO (SMC-Brd4-KO) was generated with the Cre-LoxP system. The control and SMC-Brd4-KO mice were evaluated for arterial contractility, blood pressure, arterial stiffness, and Ang II (angiotensin II)-induced vascular aging, as well as transcriptome profiling using RNA-sequencing analysis.

RESULTS

Brd4 inhibition with ARV-825, (+)-JQ1, or Brd4 knockdown through Ad-Cre virus in Brd4flox/flox SMCs led to cellular senescence. Induced SMC-Brd4-KO in adult mice prevented neointima formation. SMC-Brd4-KO mice exhibited increased aortic stiffness and blood pressure with enhanced arterial contractility ex vivo. In addition, Brd4 expression was downregulated in aortic tissues of aged mice and senescent human aortic SMCs. Furthermore, SMC-Brd4-KO mice displayed more prominent histopathologic features of vascular aging in response to Ang II infusion. Aortic tissues from SMC-Brd4-KO mice showed a more robust contractile response to Ang II and phenylephrine, accompanied by multiple genetic changes, including alterations in cytoskeleton genes. Transcriptomes of Brd4 KO aortas displayed gene signatures of dampened autophagy, intriguingly associated with a downregulation of microtubule genes, including Tuba4a (α-tubulin). Experiments in vitro with Brd4 KO SMCs demonstrated the potential role of impaired autophagy and depleted α-tubulin in mediating induction of senescence in SMCs.

CONCLUSIONS

Brd4 depletion in SMCs induces senescence, prevents neointima formation, and exacerbates vascular aging, highlighting its crucial roles in vascular functions and diseases.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Trans 10, cis 12-conjugated linoleic acid alleviates vascular fibrosis in obese mice

Controlling food intake and improving fat distribution are crucial for preventing and treating cardiovascular disease. Trans-10, cis-12 conjugated linoleic acid (t10c12-CLA) can inhibit fat deposition and facilitate bodyweight reduction, suggesting its potential to safeguard against cardiovascular disease. The transgenic (tg) mice, which inserted Pai expression cassette into the Rosa26 locus, can produce endogenous t10c12-CLA. In the present study, we used tg mice to evaluate whether the long-term existence of t10c12-CLA has a protective effect on the vascular fibrosis phenotype. The male wild-type (wt) and tg mice were marked as wt+chow, tg+chow, wt+HFD and tg+HFD groups with 24 weeks feeding the chow diet or high-fat diet (HFD). Compared with wt+chow and tg+chow mice, wt+HFD mice showed a significant (P < 0.05) increase in bodyweight and circulating lipid levels. The arterial blood vessels of wt+HFD mice displayed obvious lipid streaks and disorganization of collagen fibers. While compared with wt+HFD mice, tg+HFD mice showed a significant (P < 0.05) decrease in body weight and circulating lipid levels. The arterial blood vessels of tg+HFD mice displayed slight foam cells, predicting that t10c12-CLA can alleviates vascular fibrosis degree caused by HFD. The RNA and protein expression of proinflammatory factors in arterial blood vessels of tg+HFD mice were significantly (P < 0.05) decreased than those of wt+HFD mice. In conclusion, long-term existence of t10c12-CLA can improve lipid metabolism and circulating lipid levels and inhibit vascular inflammation and vascular fibrosis degree in obese mice, thereby preventing the further development of cardiovascular disease.

Efficacy of Naringenin against aging and degeneration of nucleus pulposus cells through IGFBP3 inhibition

Naringenin (NAR), a natural flavonoid, exerts anti-inflammatory and antioxidant pharmacology. However, the pharmacological mechanisms through which NAR prevents and treats intervertebral disc degeneration (IDD) remain unclear. We utilized bioinformatics, machine learning, and network pharmacology to identify shared targets among NAR, senescence, and IDD. Subsequently, molecular docking was conducted to evaluate NAR's binding affinity to common target. Additionally, we used IL-1β to induce senescence and degeneration in nucleus pulposus cells (NPCs) and conducted a series of cellular assays, including immunoblotting, immunofluorescence, β-galactosidase staining, cell proliferation, cell cycle analysis, and measurement of reactive oxygen species levels, to investigate NAR's impact on IL-1β-induced senescence and degeneration of NPCs. Our study revealed that Insulin-like growth factor binding protein 3 (IGFBP3) was the only common target. IGFBP3 exhibited significant differences between the IDD and healthy groups and proved to be an effective diagnostic marker for IDD. Molecular docking confirmed the binding between NAR and IGFBP3. In vitro experiments, we observed that Igfbp3 expression increased in the senescence and degeneration groups. Igfbp3 knockdown and NAR attenuated IL-1β-induced senescence and degenerative phenotypes in NPCs. In contrast, the effect of NAR was attenuated by recombinant IGFBP3 protein. In conclusion, our findings suggest that NAR plays a preventive and therapeutic role in IDD, likely achieved through the inhibition of Igfbp3 expression.

Identification of Key Genes and Immune Characteristics of SASP in Acute Ischemic Stroke

The senescence-associated secretory phenotype (SASP) is a key mechanism through which senescent cardiovascular cells contribute to plaque formation, instability, and vascular remodeling. However, the correlation between SASP and acute ischemic stroke (AIS), particularly its immune inflammation characteristics, remains underexplored and requires further elucidation. We downloaded the AIS database from the GEO database and obtained SASP genes from the SASP Atlas and related literature. Using two machine learning algorithms, we identified five hub genes. Unsupervised cluster analysis was performed on patients with AIS and DEGs separately to identify distinct gene clusters, which were then analyzed for immune characteristics. We then explored the related biological functions and immune properties of the hub genes by using various algorithms (GSEA, GSVA, and CIBERSORT). Principal component analysis (PCA) was used to generate SASP-related gene scores based on the expression of hub genes. A logistic regression algorithm was employed to establish an AIS classification diagnosis model based on the hub genes. Peripheral venous blood was collected for validation using real-time quantitative PCR (RT-qPCR). We identified five hub genes using two machine learning algorithms and validated them with RT-qPCR. Gene cluster analysis revealed two distinct clusters, SASP-related gene cluster B and differentially expressed gene cluster B, indicating that the acute AIS samples had more severe immune inflammatory response and a higher risk of disease deterioration. We constructed a gene-drug regulatory network for PIN1 and established an AIS diagnostic model and nomogram using a logistic regression algorithm. This study explored the gene expression, molecular patterns, and immunological characteristics of SASP in patients with AIS using bioinformatic methods. It provides a theoretical basis and research direction for identifying new diagnostic markers for AIS, understanding the molecular mechanism of thrombosis, and improving the classification, diagnosis, treatment, and prognosis of AIS.

Angiotensin II: A novel biomarker in vascular diseases

The renin-angiotensin system (RAS), composed mainly of renin, angiotensin, and aldosterone, is a key endocrine pathway involved in cardiovascular activity regulation. Under physiological conditions, the RAS plays a vital role in water and salt metabolism, blood pressure regulation, and electrolyte balance. Angiotensin II (Ang II) is the most important active component of the RAS, and its receptors are concentrated in vascular, pulmonary, cardiac, and renal tissues in vivo. Moreover, Ang II is closely associated with the development of vascular lesions. Ang II expression is closely associated with atherosclerosis, aortic aneurysm/dissection, ischemic stroke, hypertension, pulmonary hypertension, and type 2 diabetes mellitus. Given the significant pathophysiological role of Ang II in vascular diseases and the availability of advanced detection methods, Ang II holds promise as a reliable biomarker and therapeutic target in clinical settings. This review summarizes the mechanisms through which Ang II contributes to different vascular diseases and discusses its potential application as a biomarker for disease diagnosis.

The natural polyphenol fisetin in atherosclerosis prevention: a mechanistic review

The incidence and mortality rate of atherosclerotic cardiovascular disease (ASCVD) is increasing yearly worldwide. Recently, a growing body of evidence has unveiled the anti-atherosclerotic properties of fisetin, a natural polyphenol compound. In this article, we reviewed the pharmacologic actions of fisetin on experimental atherosclerosis and its protective effects on disease-relevant cell types such as endothelial cells, macrophages, vascular smooth muscle cells, and platelets. Based on its profound cardiovascular actions, fisetin holds potential for clinical translation and could be developed as a potential therapeutic option for atherosclerosis and its related complications. Large-scale randomized clinical trials are warranted to ascertain the safety and efficacy of fisetin in patients with or high risk for ASCVD.

Effect of dietary phenolic compounds intake on mortality in the "Seguimiento Universidad De Navarra" (SUN) Mediterranean cohort

Plant-based dietary patterns have been demonstrated to reduce the risk of non-communicable disease (NCD), including cardiovascular disease (CVD), type 2 diabetes, cancer, and all-cause mortality. Phenolic compounds (PC), abundant in plant-based foods, have been considered as instrumental in this attenuation of NCD risk. We evaluated the association between dietary intake of PC and the risk of all-cause mortality in a relatively young Mediterranean cohort of 18,173 Spanish participants in the "Seguimiento Universidad de Navarra" (SUN) project, after a median follow-up of 12.7 years. Intake of PC was estimated at baseline and repeatedly after 10-year follow-up using a 136-item validated food frequency questionnaire and the Phenol-Explorer database. During 236,329 person-years, 544 deaths were confirmed. Cox regression models compared low intake (lowest quintile) vs. high intake (the four upper quintiles merged, as a reference category) of total energy-adjusted PC intake. Adjusted hazard ratios (HR) for low PC intake among those participants aged over 45 years during follow-up were 1.32; 95% CI 1.02-1.71 for all-cause mortality, HR:1.44; 95% CI 1.02-2.02 for cancer mortality; HR: 0.88; 95% CI 0.47-1.66 for CVD mortality and HR: 1.69 95% CI 1.04-2.74 for causes of death other than cancer or CVD. In conclusion, a low intake of total PC was associated with a significantly higher risk of all-cause mortality, and, specifically, a higher risk for cancer in a relatively young cohort. Among PC classes a low intake of flavonoids and phenolic acids showed significant effects for non-cancer/non-CVD mortality. Cherries, chocolate, apples and pears, olives, and coffee, were the major sources of between-person variability for total PC intake in our Mediterranean cohort.

Piezo1 promotes vibration-induced vascular smooth muscle injury by regulating the NF-κB/p65 axis

Vibration induced damage to the peripheral circulatory system is thought to be an early stage of hand-arm vibration syndrome (HAVS) caused by occupational exposure to hand-transmitted vibration (HTV). This study investigated the mechanisms underlying vibration-induced vascular injury, focusing on the role of Piezo1, a mechanosensitive channel, and its association with the NF-κB/p65 signaling pathway. We demonstrated that vibration exposure leads to Piezo1-mediated upregulation of angiogenic chemokines, including CCL2, CCL5, CXCL1, CXCL2, and CXCL10, through the NF-κB/p65 pathway. To mimic the effects of vibration, a rat vibration model and a cellular vibration model were used. Animal and cellular models showed that vibration-induced vascular dysfunction while increasing Piezo1 expression. Piezo1 knockdown or p65 inhibition attenuated these effects, suggesting a crucial role for the Piezo1-NF-κB/p65 axis in vascular dysfunction. Furthermore, chemokines were identified as potential biomarkers for early diagnosis of HAVS in occupationally exposed individuals. These results highlight Piezo1 and the NF-κB/p65 pathway as potential therapeutic targets for HAVS and underscore the need for further validation in human samples and exploration of additional signaling mechanisms involved in vibration-induced vascular injury.

Inflammatory Pathways in Coronary Artery Disease: Which Ones to Target for Secondary Prevention?

Coronary artery disease (CAD), the build-up of atherosclerotic plaques on the wall of blood vessels, causes adverse cardiovascular events. Secondary prevention focuses on treating patients with existing plaques to prevent disease progression. Recent studies have shown that inflammation is an independent risk factor that drives disease progression, and targeting inflammation could be an effective therapeutic strategy for secondary prevention. In this review, we highlighted the roles of several inflammatory pathways in rupture and erosion, two major processes through which established plaques lead to adverse cardiovascular events. In the past 15 years, numerous clinical trials have tested the therapeutic potential of targeting these pathways, including neutralizing inflammatory cytokines and blocking signaling transduction of the inflammatory pathways. Only colchicine was approved for clinical use in patients with CAD. This is primarily due to the multifaceted roles of inflammatory pathways in disease progression. Commonly used pre-clinical models provided robust information for the onset of early disease but limited understanding of the inflammatory network in established plaques. This review will summarize lessons learned from successful and failed clinical trials to advocate for assessing inflammation in established plaques before designing therapeutics for secondary prevention.

Atheroma transcriptomics identifies ARNTL as a smooth muscle cell regulator and with clinical and genetic data improves risk stratification

BACKGROUND AND AIMS

The role of vascular smooth muscle cells (SMCs) in atherosclerosis has evolved to indicate causal genetic links with the disease. Single cell RNA sequencing (scRNAseq) studies have identified multiple cell populations of mesenchymal origin within atherosclerotic lesions, including various SMC sub-phenotypes, but it is unknown how they relate to patient clinical parameters and genetics. Here, mesenchymal cell populations in atherosclerotic plaques were correlated with major coronary artery disease (CAD) genetic variants and functional analyses performed to identify SMC markers involved in the disease.

METHODS

Bioinformatic deconvolution was done on bulk microarrays from carotid plaques in the Biobank of Karolinska Endarterectomies (BiKE, n = 125) using public plaque scRNAseq data and associated with patient clinical data and follow-up information. BiKE patients were clustered based on the deconvoluted cell fractions. Quantitative trait loci (QTLs) analyses were performed to predict the effect of CAD associated genetic variants on mesenchymal cell fractions (cfQTLs) and gene expression (eQTLs) in plaques.

RESULTS

Lesions from symptomatic patients had higher fractions of Type 1 macrophages and pericytes, but lower fractions of classical and modulated SMCs compared with asymptomatic ones, particularly females. Presence of diabetes or statin treatment did not affect the cell fraction distribution. Clustering based on plaque cell fractions, revealed three patient groups, with relative differences in their stability profiles and associations to stroke, even during long-term follow-up. Several single nucleotide polymorphisms associated with plaque mesenchymal cell fractions, upstream of the circadian rhythm gene ARNTL were identified. In vitro silencing of ARNTL in human carotid SMCs increased the expression of contractile markers and attenuated cell proliferation.

CONCLUSIONS

This study shows the potential of combining scRNAseq data with vertically integrated clinical, genetic, and transcriptomic data from a large biobank of human plaques, for refinement of patient vulnerability and risk prediction stratification. The study revealed novel CAD-associated variants that may be functionally linked to SMCs in atherosclerotic plaques. Specifically, variants in the ARNTL gene may influence SMC ratios and function, and its role as a regulator of SMC proliferation should be further investigated.

Network Pharmacology and Experimental Validation to Elucidate the Pharmacological Mechanisms of Luteolin Against Chondrocyte Senescence

BACKGROUND

Luteolin, a flavonoid found in various medicinal plants, has shown promising antioxidant, anti-inflammatory, and anti-aging properties. The cartilaginous endplate (CEP) represents a crucial constituent of the intervertebral disc (IVD), assuming a pivotal responsibility in upholding both the structural and functional stability of the IVD.

OBJECTIVE

Exploring the precise mechanism underlying the protective effects of luteolin against senescence and degeneration of endplate chondrocytes (EPCs).

METHODS

Relevant targets associated with luteolin and aging were obtained from publicly available databases. To ascertain cellular functions and signaling pathways, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were employed. Core genes were identified through the construction of a protein-protein interaction (PPI) network. Molecular docking (MD) was utilized to assess the binding affinity of luteolin to these core genes. Finally, the impact of luteolin on the senescence and degeneration of EPCs was evaluated in an in vitro cellular senescence model induced by tert-butyl hydroperoxide (TBHP).

RESULTS

There are 145 overlapping targets between luteolin and senescence. Analysis using GO revealed that these targets primarily participate in cellular response to oxidative stress and reactive oxygen species. KEGG analysis demonstrated that these markers mainly associate with signaling pathways such as p53 and PI3K-Akt. MD simulations exhibited luteolin's binding affinity to P53, Cyclin-dependent kinase (CDK)2, and CDK4. Cell cycle, cell proliferation, and β- galactosidase assays confirmed that luteolin mitigated senescence in SW1353 cells. Western blot assays exhibited that luteolin significantly suppressed the expression of Matrix Metallopeptidase (MMP) 13, P53, and P21, while concurrently promoting CDK2, CDK4, and Collagen Type II Alpha 1 (COL2A1) expression.

CONCLUSION

In summary, luteolin demonstrated beneficial properties against aging and degeneration in EPCs, offering novel insights to mitigate the progression of intervertebral disc degeneration (IVDD).

The role of CYP-sEH derived lipid mediators in regulating mitochondrial biology and cellular senescence: implications for the aging heart

Cellular senescence is a condition characterized by stable, irreversible cell cycle arrest linked to the aging process. The accumulation of senescent cells in the cardiac muscle can contribute to various cardiovascular diseases (CVD). Telomere shortening, epigenetic modifications, DNA damage, mitochondrial dysfunction, and oxidative stress are known contributors to the onset of cellular senescence in the heart. The link between mitochondrial processes and cellular senescence contributed to the age-related decline in cardiac function. These include changes in mitochondrial functions and behaviours that arise from various factors, including impaired dynamics, dysregulated biogenesis, mitophagy, mitochondrial DNA (mtDNA), reduced respiratory capacity, and mitochondrial structural changes. Thus, regulation of mitochondrial biology has a role in cellular senescence and cardiac function in aging hearts. Targeting senescent cells may provide a novel therapeutic approach for treating and preventing CVD associated with aging. CYP epoxygenases metabolize N-3 and N-6 polyunsaturated fatty acids (PUFA) into epoxylipids that are readily hydrolyzed to diol products by soluble epoxide hydrolase (sEH). Increasing epoxylipids levels or inhibition of sEH has demonstrated protective effects in the aging heart. Evidence suggests they may play a role in cellular senescence by regulating mitochondria, thus reducing adverse effects of aging in the heart. In this review, we discuss how mitochondria induce cellular senescence and how epoxylipids affect the senescence process in the aged heart.

Linking peripheral atherosclerosis to blood-brain barrier disruption: elucidating its role as a manifestation of cerebral small vessel disease in vascular cognitive impairment

Aging plays a pivotal role in the pathogenesis of cerebral small vessel disease (CSVD), contributing to the onset and progression of vascular cognitive impairment and dementia (VCID). In older adults, CSVD often leads to significant pathological outcomes, including blood-brain barrier (BBB) disruption, which in turn triggers neuroinflammation and white matter damage. This damage is frequently observed as white matter hyperintensities (WMHs) in neuroimaging studies. There is mounting evidence that older adults with atherosclerotic vascular diseases, such as peripheral artery disease, ischemic heart disease, and carotid artery stenosis, face a heightened risk of developing CSVD and VCID. This review explores the complex relationship between peripheral atherosclerosis, the pathogenesis of CSVD, and BBB disruption. It explores the continuum of vascular aging, emphasizing the shared pathomechanisms that underlie atherosclerosis in large arteries and BBB disruption in the cerebral microcirculation, exacerbating both CSVD and VCID. By reviewing current evidence, this paper discusses the impact of endothelial dysfunction, cellular senescence, inflammation, and oxidative stress on vascular and neurovascular health. This review aims to enhance understanding of these complex interactions and advocate for integrated approaches to manage vascular health, thereby mitigating the risk and progression of CSVD and VCID.

Therapeutic Suppression of Atherosclerotic Burden and Vulnerability via Dll4 Inhibition in Plaque Macrophages Using Dual-Targeted Liposomes

Atherosclerosis, characterized by chronic inflammation within the arterial wall, remains a pivotal concern in cardiovascular health. We developed a dual-targeted liposomal system encapsulating Dll4-targeting siRNA, designed to selectively bind to pro-inflammatory M1 macrophages through surface conjugation with anti-F4/80 and anti-CD68 antibodies. The Dll4-targeting siRNA is then delivered to the macrophages, where it silences Dll4 expression, inhibiting Notch signaling and reducing plaque vulnerability. Emphasizing accuracy in targeting, the system demonstrates effective suppression of Dll4, a key modulator of atherosclerotic progression, and vulnerability via VSMCs phenotypic conversion and senescence. By employing liposomes for siRNA delivery, we observed enhanced stability and specificity of the siRNA. Alongside the therapeutic efficacy, our study also evaluated the safety profile and pharmacokinetics of the dual-targeted liposomal system, revealing favorable outcomes with minimal off-target effects and optimal biodistribution. The integration of RNA interference techniques with advanced nanotechnological methodologies signifies the importance of targeted delivery in this therapeutic approach. Preliminary findings suggest a potential attenuation in plaque development and vulnerability, indicating the therapeutic promise of this approach. This research emphasizes the potential of nanocarrier-mediated precision targeting combined with a reassuring safety and pharmacokinetic profile for advancing atherosclerosis therapeutic strategies.

Immunohistochemical Localization of Fibroblast Activation Protein in Coronary Arteries with Different Forms of Atherosclerosis

Background: Fibroblast activation protein (FAP) is a cell surface glycoprotein expressed by myofibroblasts in areas of active tissue remodeling. It plays a potentially important role in cardiac remodeling, atherosclerotic plaque formation, and plaque rupture. Given the distinct pathophysiology and morphology of different forms of atherosclerosis, we analyzed FAP expression in human coronary vessels with no coronary artery disease, atherosclerotic plaques at different levels of progression, and other distinct forms of coronary disease in post bypass vein grafting and cardiac allograft vasculopathy after a heart transplant. Methods: Immunohistochemical staining with monoclonal F19 mouse anti-human FAP antibody was performed to identify FAP in human atherosclerotic plaques, coronary bypass atherosclerosis, and post-transplant arteriosclerosis. The presence and distribution of FAP in different types and stages of human atherosclerosis were compared. Results: There was no FAP staining in patients with no significant coronary disease. All different types of human atherosclerotic lesioning lesions showed the presence of FAP expression, with different staining patterns in advanced atherosclerotic plaque, vein graft atherosclerosis lesions, and arteriosclerosis after a heart transplant. Conclusions: These data suggest that FAP may be a potential diagnostic marker and target for interventions, not only in coronary atherosclerotic plaque, but also in other forms of coronary disease, which have distinct pathophysiologies and currently limited treatment options.

Association between premature vascular smooth muscle cells senescence and vascular inflammation in Takayasu's arteritis

OBJECTIVES

Arterial wall inflammation and remodelling are the characteristic features of Takayasu's arteritis (TAK). It has been proposed that vascular smooth muscle cells (VSMCs) are the main targeted cells of inflammatory damage and participate in arterial remodelling in TAK. Whether VSMCs are actively involved in arterial wall inflammation has not been elucidated. Studies have shown that cellular senescence in tissue is closely related to local inflammation persistence. We aimed to investigate whether VSMCs senescence contributes to vascular inflammation and the prosenescent factors in TAK.

METHODS

VSMCs senescence and senescence-associated secretory phenotype were detected by histological examination, bulk RNA-Seq and single-cell RNA-seq conducted on vascular surgery samples of TAK patients. The key prosenescent factors and the downstream signalling pathway were investigated in a series of in vitro and ex vivo experiments.

RESULTS

Histological findings, primary cell culture and transcriptomic analyses demonstrated that VSMCs of TAK patients had the features of premature senescence and contributed substantially to vascular inflammation by upregulating the expression of senescence-associated inflammatory cytokines. IL-6 was found to be the critical cytokine that drove VSMCs senescence and senescence-associated mitochondrial dysfunction in TAK. Mechanistically, IL-6-induced non-canonical mitochondrial localisation of phosphorylated STAT3 (Tyr705) prevented mitofusin 2 (MFN2) from proteasomal degradation, and subsequently promoted senescence-associated mitochondrial dysfunction and VSMCs senescence. Mitochondrial STAT3 or MFN2 inhibition ameliorated VSMCs senescence in ex vivo cultured arteries of TAK patients.

CONCLUSIONS

VSMCs present features of cellular senescence and are actively involved in vascular inflammation in TAK. Vascular IL-6-mitochondrial STAT3-MFN2 signalling is an important driver of VSMCs senescence.

α-Terpineol Induces Shelterin Components TRF1 and TRF2 to Mitigate Senescence and Telomere Integrity Loss via A Telomerase-Independent Pathway

Cellular senescence is a hallmark of aging characterized by irreversible growth arrest and functional decline. Progressive telomeric DNA shortening in dividing somatic cells, programmed during development, leads to critically short telomeres that trigger replicative senescence and thereby contribute to aging. Therefore, protecting telomeres from DNA damage is essential in order to avoid entry into senescence and organismal aging. In several organisms, including mammals, telomeres are protected by a protein complex named shelterin that prevents DNA damage at the chromosome ends through the specific function of its subunits. Here, we reveal that the nuclear protein levels of shelterin components TRF1 and TRF2 decline in fibroblasts reaching senescence. Notably, we identify α-terpineol as an activator that effectively enhances TRF1 and TRF2 levels in a telomerase-independent manner, counteracting the senescence-associated decline in these crucial proteins. Moreover, α-terpineol ameliorates the cells' response to oxidative DNA damage, particularly at the telomeric regions, thus preserving telomere length and delaying senescence. More importantly, our findings reveal the significance of the PI3K/AKT pathway in the regulation of shelterin components responsible for preserving telomere integrity. In conclusion, this study deepens our understanding of the molecular pathways involved in senescence-associated telomere dysfunction and highlights the potential of shelterin components to serve as targets of therapeutic interventions, aimed at promoting healthy aging and combating age-related diseases.

Atherosclerotic burden and cerebral small vessel disease: exploring the link through microvascular aging and cerebral microhemorrhages

Cerebral microhemorrhages (CMHs, also known as cerebral microbleeds) are a critical but frequently underestimated aspect of cerebral small vessel disease (CSVD), bearing substantial clinical consequences. Detectable through sensitive neuroimaging techniques, CMHs reveal an extensive pathological landscape. They are prevalent in the aging population, with multiple CMHs often being observed in a given individual. CMHs are closely associated with accelerated cognitive decline and are increasingly recognized as key contributors to the pathogenesis of vascular cognitive impairment and dementia (VCID) and Alzheimer's disease (AD). This review paper delves into the hypothesis that atherosclerosis, a prevalent age-related large vessel disease, extends its pathological influence into the cerebral microcirculation, thereby contributing to the development and progression of CSVD, with a specific focus on CMHs. We explore the concept of vascular aging as a continuum, bridging macrovascular pathologies like atherosclerosis with microvascular abnormalities characteristic of CSVD. We posit that the same risk factors precipitating accelerated aging in large vessels (i.e., atherogenesis), primarily through oxidative stress and inflammatory pathways, similarly instigate accelerated microvascular aging. Accelerated microvascular aging leads to increased microvascular fragility, which in turn predisposes to the formation of CMHs. The presence of hypertension and amyloid pathology further intensifies this process. We comprehensively overview the current body of evidence supporting this interconnected vascular hypothesis. Our review includes an examination of epidemiological data, which provides insights into the prevalence and impact of CMHs in the context of atherosclerosis and CSVD. Furthermore, we explore the shared mechanisms between large vessel aging, atherogenesis, microvascular aging, and CSVD, particularly focusing on how these intertwined processes contribute to the genesis of CMHs. By highlighting the role of vascular aging in the pathophysiology of CMHs, this review seeks to enhance the understanding of CSVD and its links to systemic vascular disorders. Our aim is to provide insights that could inform future therapeutic approaches and research directions in the realm of neurovascular health.

Phylloquinone improves endothelial function, inhibits cellular senescence, and vascular inflammation

Phylloquinon (PK) and menaquinones (MK) are both naturally occurring compounds belonging to vitamin K group. Present study aimed to comprehensively analyze the influence of PK in several models of vascular dysfunction to determine whether PK has vasoprotective properties, similar to those previously described for MK. Effects of PK and MK on endothelial dysfunction were studied in ApoE/LDLR-/- mice in vivo, in the isolated aorta incubated with TNF, and in vascular cells as regard inflammation and cell senescence (including replicative and stress-induced models of senescence). Moreover, the vascular conversion of exogenous vitamins to endogenous MK-4 was analyzed. PK, as well as MK, given for 8 weeks in diet (10 mg/kg) resulted in comparable improvement in endothelial function in the ApoE/LDLR-/- mice. Similarly, PK and MK prevented TNF-induced impairment of endothelium-dependent vasorelaxation in the isolated aorta. In in vitro studies in endothelial and vascular smooth muscle cells, we identified that both PK and MK displayed anti-senescence effects via decreasing DNA damage while in endothelial cells anti-inflammatory activity was ascribed to the modulation of NFκB activation. The activity of PK and MK was comparable in terms of their effect on senescence and inflammation. Presence of endogenous synthesis of MK-4 from PK in aorta and endothelial and smooth muscle cells suggests a possible involvement of MK in vascular effects of PK. In conclusion, PK and MK display comparable vasoprotective effects, which may be ascribed, at least in part, to the inhibition of cell senescence and inflammation. The vasoprotective effect of PK in the vessel wall can be related to the direct effects of PK, as well as to the action of MK formed from PK in the vascular wall.

MG-132 activates sodium palmitate-induced autophagy in human vascular smooth muscle cells and inhibits senescence via the PI3K/AKT/mTOR axis

OBJECTIVE

This study aimed to reveal the role and mechanism of MG-132 in delaying hyperlipidemia-induced senescence of vascular smooth muscle cells (VSMCs).

METHODS

Immunohistochemistry and hematoxylin-eosin staining confirmed the therapeutic effect of MG-132 on arterial senescence in vivo and its possible mechanism. Subsequently, VSMCs were treated with sodium palmitate (PA), an activator (Recilisib) or an inhibitor (Pictilisib) to activate or inhibit PI3K, and CCK-8 and EdU staining, wound healing assays, Transwell cell migration assays, autophagy staining assays, reactive oxygen species assays, senescence-associated β-galactosidase staining, and Western blotting were performed to determine the molecular mechanism by which MG-132 inhibits VSMC senescence. Validation of the interaction between MG-132 and PI3K using molecular docking.

RESULTS

Increased expression of p-PI3K, a key protein of the autophagy regulatory system, and decreased expression of the autophagy-associated proteins Beclin 1 and ULK1 were observed in the aortas of C57BL/6J mice fed a high-fat diet (HFD), and autophagy was inhibited in aortic smooth muscle. MG-132 inhibits atherosclerosis by activating autophagy in VSMCs to counteract PA-induced cell proliferation, migration, oxidative stress, and senescence, thereby inhibiting VSMC senescence in the aorta. This process is achieved through the PI3K/AKT/mTOR signaling pathway.

CONCLUSION

MG-132 activates autophagy by inhibiting the PI3K/AKT/mTOR pathway, thereby inhibiting palmitate-induced proliferation, migration, and oxidative stress in vascular smooth muscle cells and suppressing their senescence.

STING1-accelerated vascular smooth muscle cell senescence-associated vascular calcification in diabetes is ameliorated by oleoylethanolamide via improved mitochondrial DNA oxidative damage

Vascular calcification is a prevalent hallmark of cardiovascular risk in elderly and diabetic individuals. Senescent vascular smooth muscle cells (VSMCs) participate in calcification; however, the associated underlying mechanisms remain unknown. Aberrant activation of the cytosolic DNA sensing adaptor stimulator of interferon gene 1 (STING1) caused by cytosolic DNA, particularly that leaked from damaged mitochondria, is a catalyst for aging-related diseases. Although oleoylethanolamide (OEA) is an endogenous bioactive lipid mediator with lipid overload-associated vasoprotective effects, its benefit in diabetic vascular calcification remains uncharacterized. This study focused on the role of STING1 in mitochondrial dysfunction-mediated calcification and premature VMSC senescence in diabetes and the effects of OEA on these pathological processes. In diabetic in vivo rat/mouse aorta calcification models and an in vitro VSMC calcification model induced by Nε-carboxymethyl-lysine (CML), senescence levels, STING1 signaling activation, and mitochondrial damage markers were significantly augmented; however, these alterations were markedly alleviated by OEA, partially in a nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent manner, and similar anti-calcification and senescence effects were observed in STING1-knockout mice and STING1-knockdown VSMCs. Mechanistically, mitochondrial DNA (mtDNA) damage was aggravated by CML in a reactive oxygen species-dependent manner, followed by mtDNA leakage into the cytosol, contributing to VSMC senescence-associated calcification via STING1 pathway activation. OEA treatment significantly attenuated the aforementioned cytotoxic effects of CML by enhancing cellular antioxidant capacity through the maintenance of Nrf2 translocation to the nucleus. Collectively, targeting STING1, a newly defined VSMC senescence regulator, contributes to anti-vascular calcification effects.

Syndecan-1 as a predictor of vulnerable atherosclerotic plaques

Aims

Cardiovascular disease remains a major global health concern, with atherosclerosis (AS) being a significant contributor. Vulnerable plaques play a critical role in acute cardiovascular events. Syndecan-1 (SDC-1), a vital membrane proteoglycan in the vascular endothelial glycocalyx, is believed to be associated with plaque progression. However, its precise relationship with severity and vulnerability of atherosclerotic plaque remains unclear. This study aimed to investigate SDC-1 expression and its potential correlation with plaque vulnerability in ApoE-/- atherosclerosis mouse model.

Methods and results

Eight-week-old mice were induced into the AS model using a high-fat diet (HFD) and/or partial ligation of the left common carotid artery (PLCA), with a chow diet (CD) control group. After 16 weeks, plaques in the aortic root showed the following order: HFD + PLCA group > HFD group > CD + PLCA group > CD group. Immunohistochemistry revealed heightened accumulation of lipid/foam cells and CD68-labeled macrophages in the plaques, elevated vascular endothelial growth factor (VEGF), and matrix Metalloproteinase-9 (MMP-9) in the HFD + PLCA group's plaques, along with reduced collagen and α-SMA-labeled smooth muscle cells, resulting in the highest vulnerability index value. Immunohistofluorescence analysis of frozen plaque sections showed significantly higher SDC-1 expression in the AS mice group compared to the CD group, both positively correlated with plaque vulnerability. Serum analysis demonstrated elevated levels of SDC1, sphingosine 1-phosphate (S1P), and VEGF-A in the AS mice, all positively correlated with plaque vulnerability. Multivariate analysis identified SDC1 as an independent predictor of plaque vulnerability.

Conclusion

This study enhances our understanding of plaque vulnerability mechanisms and presents SDC1 as a potential biomarker for atherosclerosis. These findings underscore the importance of addressing modifiable risk factors, such as diet and hemodynamics and suggest the utility of serum SDC1 as a valuable clinical marker. Ultimately, these insights may lead to more effective strategies in combating cardiovascular diseases and improving patient outcomes.

Implications of endoplasmic reticulum stress and autophagy in aging and cardiovascular diseases

The average lifespan of humans has been increasing, resulting in a rapidly rising percentage of older individuals and high morbidity of aging-associated diseases, especially cardiovascular diseases (CVDs). Diverse intracellular and extracellular factors that interrupt homeostatic functions in the endoplasmic reticulum (ER) induce ER stress. Cells employ a dynamic signaling pathway of unfolded protein response (UPR) to buffer ER stress. Recent studies have demonstrated that ER stress triggers various cellular processes associated with aging and many aging-associated diseases, including CVDs. Autophagy is a conserved process involving lysosomal degradation and recycling of cytoplasmic components, proteins, organelles, and pathogens that invade the cytoplasm. Autophagy is vital for combating the adverse influence of aging on the heart. The present report summarizes recent studies on the mechanism of ER stress and autophagy and their overlap in aging and on CVD pathogenesis in the context of aging. It also discusses possible therapeutic interventions targeting ER stress and autophagy that might delay aging and prevent or treat CVDs.

The role of cellular senescence in ovarian aging

This review explores the relationship between ovarian aging and senescent cell accumulation, as well as the efficacy of senolytics to improve reproductive longevity. Reproductive longevity is determined by the age-associated decline in ovarian reserve, resulting in reduced fertility and eventually menopause. Cellular senescence is a state of permanent cell cycle arrest and resistance to apoptosis. Senescent cells accumulate in several tissues with advancing age, thereby promoting chronic inflammation and age-related diseases. Ovaries also appear to accumulate senescent cells with age, which might contribute to aging of the reproductive system and whole organism through SASP production. Importantly, senolytic drugs can eliminate senescent cells and may present a potential intervention to mitigate ovarian aging. Herein, we review the current literature related to the efficacy of senolytic drugs for extending the reproductive window in mice.

Progeria-based vascular model identifies networks associated with cardiovascular aging and disease

Hutchinson-Gilford Progeria syndrome (HGPS) is a lethal premature aging disorder caused by a de novo heterozygous mutation that leads to the accumulation of a splicing isoform of Lamin A termed progerin. Progerin expression deregulates the organization of the nuclear lamina and the epigenetic landscape. Progerin has also been observed to accumulate at low levels during normal aging in cardiovascular cells of adults that do not carry genetic mutations linked with HGPS. Therefore, the molecular mechanisms that lead to vascular dysfunction in HGPS may also play a role in vascular aging-associated diseases, such as myocardial infarction and stroke. Here, we show that HGPS patient-derived vascular smooth muscle cells (VSMCs) recapitulate HGPS molecular hallmarks. Transcriptional profiling revealed cardiovascular disease remodeling and reactive oxidative stress response activation in HGPS VSMCs. Proteomic analyses identified abnormal acetylation programs in HGPS VSMC replication fork complexes, resulting in reduced H4K16 acetylation. Analysis of acetylation kinetics revealed both upregulation of K16 deacetylation and downregulation of K16 acetylation. This correlates with abnormal accumulation of error-prone nonhomologous end joining (NHEJ) repair proteins on newly replicated chromatin. The knockdown of the histone acetyltransferase MOF recapitulates preferential engagement of NHEJ repair activity in control VSMCs. Additionally, we find that primary donor-derived coronary artery vascular smooth muscle cells from aged individuals show similar defects to HGPS VSMCs, including loss of H4K16 acetylation. Altogether, we provide insight into the molecular mechanisms underlying vascular complications associated with HGPS patients and normative aging.

Involvement of Matricellular Proteins in Cellular Senescence: Potential Therapeutic Targets for Age-Related Diseases

Senescence is a physiological and pathological cellular program triggered by various types of cellular stress. Senescent cells exhibit multiple characteristic changes. Among them, the characteristic flattened and enlarged morphology exhibited in senescent cells is observed regardless of the stimuli causing the senescence. Several studies have provided important insights into pro-adhesive properties of cellular senescence, suggesting that cell adhesion to the extracellular matrix (ECM), which is involved in characteristic morphological changes, may play pivotal roles in cellular senescence. Matricellular proteins, a group of structurally unrelated ECM molecules that are secreted into the extracellular environment, have the unique ability to control cell adhesion to the ECM by binding to cell adhesion receptors, including integrins. Recent reports have certified that matricellular proteins are closely involved in cellular senescence. Through this biological function, matricellular proteins are thought to play important roles in the pathogenesis of age-related diseases, including fibrosis, osteoarthritis, intervertebral disc degeneration, atherosclerosis, and cancer. This review outlines recent studies on the role of matricellular proteins in inducing cellular senescence. We highlight the role of integrin-mediated signaling in inducing cellular senescence and provide new therapeutic options for age-related diseases targeting matricellular proteins and integrins.

Application potential of senolytics in clinical treatment

Of the factors studied in individual ageing, the accumulation of senescent cells has been considered as an essential cause of organ degeneration to eventually initiate age-related diseases. Cellular senescence is attributed to the accumulation of damage for an inducement in the activation of cell cycle inhibitory pathways, resulting the cell permanently withdraw from the cell proliferation cycle. Further, senescent cells will activate the inflammatory factor secretion pathway to promote the development of various age-related diseases. Senolytics, a small molecule compound, can delay disease development and extend mammalian lifespan. The evidence from multiple trials shows that the targeted killing of senescent cells has a significant clinical application for the treatment of age-related diseases. In addition, senolytics are also significant for the development of ageing research in solid organ transplantation, which can fully develop the potential of elderly organs and reduce the age gap between demand and supply. We conclude that the main characteristics of cellular senescence, the anti-ageing drug senolytics in the treatment of chronic diseases and organ transplantation, and the latest clinical progress of related researches in order to provide a theoretical basis for the prevention and treatment of ageing and related diseases.

Focus on senescence: Clinical significance and practical applications

The older population is increasing worldwide, and life expectancy is continuously rising, predominantly thanks to medical and technological progress. Healthspan refers to the number of years an individual can live in good health. From a gerontological viewpoint, the mission is to extend the life spent in good health, promoting well-being and minimizing the impact of aging-related diseases to slow the aging process. Biologically, aging is a malleable process characterized by an intra- and inter-individual heterogeneous and dynamic balance between accumulating damage and repair mechanisms. Cellular senescence is a key component of this process, with senescent cells accumulating in different tissues and organs, leading to aging and age-related disease susceptibility over time. Removing senescent cells from the body or slowing down the burden rate has been proposed as an efficient way to reduce age-dependent deterioration. In animal models, senotherapeutic molecules can extend life expectancy and lifespan by either senolytic or senomorphic activity. Much research shows that dietary and physical activity-driven lifestyle interventions protect against senescence. This narrative review aims to summarize the current knowledge on targeting senescent cells to reduce the risk of age-related disease in animal models and their translational potential for humans. We focused on studies that have examined the potential role of senotherapeutics in slowing the aging process and modifying age-related disease burdens. The review concludes with a general discussion of the mechanisms underlying this unique trajectory and its implications for future research.

Associations of measured and genetically predicted leukocyte telomere length with vascular phenotypes: a population-based study

Shorter leukocyte telomere length (LTL) is associated with cardiovascular dysfunction. Whether this association differs between measured and genetically predicted LTL is still unclear. Moreover, the molecular processes underlying the association remain largely unknown. We used baseline data of the Rhineland Study, an ongoing population-based cohort study in Bonn, Germany [56.2% women, age: 55.5 ± 14.0 years (range 30 - 95 years)]. We calculated genetically predicted LTL in 4180 participants and measured LTL in a subset of 1828 participants with qPCR. Using multivariable regression, we examined the association of measured and genetically predicted LTL, and the difference between measured and genetically predicted LTL (ΔLTL), with four vascular functional domains and the overall vascular health. Moreover, we performed epigenome-wide association studies of three LTL measures. Longer measured LTL was associated with better microvascular and cardiac function. Longer predicted LTL was associated with better cardiac function. Larger ΔLTL was associated with better microvascular and cardiac function and overall vascular health, independent of genetically predicted LTL. Several CpGs were associated (p < 1e-05) with measured LTL (n = 5), genetically predicted LTL (n = 8), and ΔLTL (n = 27). Genes whose methylation status was associated with ΔLTL were enriched in vascular endothelial signaling pathways and have been linked to environmental exposures, cardiovascular diseases, and mortality. Our findings suggest that non-genetic causes of LTL contribute to microvascular and cardiac function and overall vascular health, through an effect on the vascular endothelial signaling pathway. Interventions that counteract LTL may thus improve vascular function.

SIRT1-dependent PGC-1α deacetylation by SRT1720 rescues progression of atherosclerosis by enhancing mitochondrial function

Vascular smooth muscle cell (VSMC) senescence promotes atherosclerosis via lipid-mediated mitochondrial dysfunction and oxidative stress. However, the mechanisms of mitochondrial dysfunction and VSMC senescence in atherosclerosis have not been established. Here, we investigated the mechanisms whereby signaling pathways regulated by SRT1720 enhance or regulate mitochondrial functions in atherosclerotic VSMCs to suppress atherosclerosis. Initially, we examined the effect of SRT1720 on oleic acid (OA)-induced atherosclerosis. Atherosclerotic VSMCs exhibited elevated expressions of BODIPY and ADRP (adipose differentiation-related protein) and associated intracellular lipid droplet markers. In addition, the expression of collagen I was upregulated by OA, while the expressions of elastin and α-SMA were downregulated. mtDNA copy numbers, an ATP detection assay, transmission electron microscopy (TEM) imaging of mitochondria, mitochondria membrane potentials (assessed using JC-1 probe), and levels of mitochondrial oxidative phosphorylation (OXPHOS) were used to examine the effects of SRT1720 on OA-induced mitochondrial dysfunction. SRT1720 reduced mtDNA damage and accelerated mitochondria repair in VSMCs with OA-induced mitochondria dysfunction. In addition, mitochondrial reactive oxygen species (mtROS) levels were downregulated by SRT1720 in OA-treated VSMCs. Importantly, SRT1720 significantly increased SIRT1 and PGC-1α expression levels, but VSMCs senescence, inflammatory response, and atherosclerosis phenotypes were not recovered by treating cells with EX527 and SR-18292 before SRT1720. Mechanistically, the upregulations of SIRT1 and PGC-1α deacetylation by SRT1720 restored mitochondrial function, and consequently suppressed VSMC senescence and atherosclerosis-associated proteins and phenotypes. Collectively, this study indicates that SRT1720 can attenuate OA-induced atherosclerosis associated with VSMC senescence and mitochondrial dysfunction via SIRT1-mediated deacetylation of the PGC-1α pathway.

The interplay of collagen, macrophages, and microcalcification in atherosclerotic plaque cap rupture mechanics

The rupture of an atherosclerotic plaque cap overlying a lipid pool and/or necrotic core can lead to thrombotic cardiovascular events. In essence, the rupture of the plaque cap is a mechanical event, which occurs when the local stress exceeds the local tissue strength. However, due to inter- and intra-cap heterogeneity, the resulting ultimate cap strength varies, causing proper assessment of the plaque at risk of rupture to be lacking. Important players involved in tissue strength include the load-bearing collagenous matrix, macrophages, as major promoters of extracellular matrix degradation, and microcalcifications, deposits that can exacerbate local stress, increasing tissue propensity for rupture. This review summarizes the role of these components individually in tissue mechanics, along with the interplay between them. We argue that to be able to improve risk assessment, a better understanding of the effect of these individual components, as well as their reciprocal relationships on cap mechanics, is required. Finally, we discuss potential future steps, including a holistic multidisciplinary approach, multifactorial 3D in vitro model systems, and advancements in imaging techniques. The obtained knowledge will ultimately serve as input to help diagnose, prevent, and treat atherosclerotic cap rupture.

FTO Stabilizes MIS12 to Inhibit Vascular Smooth Muscle Cell Senescence in Atherosclerotic Plaque

Purpose

Atherosclerosis is the main cause of atherosclerotic cardiovascular disease (CVD). Here, we aimed to uncover the role and mechanisms of fat mass and obesity-associated genes (FTO) in the regulation of vascular smooth muscle cell (VSMC) senescence in atherosclerotic plaques.

Methods

ApoE-/- mice fed a high-fat diet (HFD) were used to establish an atherosclerotic animal model. Immunohistochemistry, and the staining of hematoxylin-eosin, Oil Red O, Sirius red, and Masson were performed to confirm the role of FTO in atherosclerosis in vivo. Subsequently, FTO expression in primary VSMCs is either upregulated or downregulated. Oxidized low-density lipoprotein (ox-LDL) was used to treat VSMCs, followed by EdU staining, flow cytometry, senescence-associated β-galactosidase (SA-β-gal) staining, immunofluorescence, telomere detection, RT-qPCR, and Western blotting to determine the molecular mechanisms by which FTO inhibits VSMC senescence.

Results

Decreased FTO expression was observed in progressive atherosclerotic plaques of ApoE-/- mice fed with HFD. FTO upregulation inhibits atherosclerotic lesions in mice. FTO inhibits VSMC aging in atherosclerotic plaques by helping VSMC withstand ox-LDL-induced cell cycle arrest and senescence. This process is achieved by stabilizing the MIS12 protein in VSMC through a proteasome-mediated pathway.

Conclusion

FTO inhibits VSMC senescence and subsequently slows the progression of atherosclerotic plaques by stabilizing the MIS12 protein.

Peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) family in physiological and pathophysiological process and diseases

Peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) family (PGC-1s), consisting of three members encompassing PGC-1α, PGC-1β, and PGC-1-related coactivator (PRC), was discovered more than a quarter-century ago. PGC-1s are essential coordinators of many vital cellular events, including mitochondrial functions, oxidative stress, endoplasmic reticulum homeostasis, and inflammation. Accumulating evidence has shown that PGC-1s are implicated in many diseases, such as cancers, cardiac diseases and cardiovascular diseases, neurological disorders, kidney diseases, motor system diseases, and metabolic disorders. Examining the upstream modulators and co-activated partners of PGC-1s and identifying critical biological events modulated by downstream effectors of PGC-1s contribute to the presentation of the elaborate network of PGC-1s. Furthermore, discussing the correlation between PGC-1s and diseases as well as summarizing the therapy targeting PGC-1s helps make individualized and precise intervention methods. In this review, we summarize basic knowledge regarding the PGC-1s family as well as the molecular regulatory network, discuss the physio-pathological roles of PGC-1s in human diseases, review the application of PGC-1s, including the diagnostic and prognostic value of PGC-1s and several therapies in pre-clinical studies, and suggest several directions for future investigations. This review presents the immense potential of targeting PGC-1s in the treatment of diseases and hopefully facilitates the promotion of PGC-1s as new therapeutic targets.

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.

Palmitic acid in type 2 diabetes mellitus promotes atherosclerotic plaque vulnerability via macrophage Dll4 signaling

Patients with Type 2 Diabetes Mellitus are increasingly susceptible to atherosclerotic plaque vulnerability, leading to severe cardiovascular events. In this study, we demonstrate that elevated serum levels of palmitic acid, a type of saturated fatty acid, are significantly linked to this enhanced vulnerability in patients with Type 2 Diabetes Mellitus. Through a combination of human cohort studies and animal models, our research identifies a key mechanistic pathway: palmitic acid induces macrophage Delta-like ligand 4 signaling, which in turn triggers senescence in vascular smooth muscle cells. This process is critical for plaque instability due to reduced collagen synthesis and deposition. Importantly, our findings reveal that macrophage-specific knockout of Delta-like ligand 4 in atherosclerotic mice leads to reduced plaque burden and improved stability, highlighting the potential of targeting this pathway. These insights offer a promising direction for developing therapeutic strategies to mitigate cardiovascular risks in patients with Type 2 Diabetes Mellitus.

Heat shock response during the resolution of inflammation and its progressive suppression in chronic-degenerative inflammatory diseases

The heat shock response (HSR) is a crucial biochemical pathway that orchestrates the resolution of inflammation, primarily under proteotoxic stress conditions. This process hinges on the upregulation of heat shock proteins (HSPs) and other chaperones, notably the 70 kDa family of heat shock proteins, under the command of the heat shock transcription factor-1. However, in the context of chronic degenerative disorders characterized by persistent low-grade inflammation (such as insulin resistance, obesity, type 2 diabetes, nonalcoholic fatty liver disease, and cardiovascular diseases) a gradual suppression of the HSR does occur. This work delves into the mechanisms behind this phenomenon. It explores how the Western diet and sedentary lifestyle, culminating in the endoplasmic reticulum stress within adipose tissue cells, trigger a cascade of events. This cascade includes the unfolded protein response and activation of the NOD-like receptor pyrin domain-containing protein-3 inflammasome, leading to the emergence of the senescence-associated secretory phenotype and the propagation of inflammation throughout the body. Notably, the activation of the NOD-like receptor pyrin domain-containing protein-3 inflammasome not only fuels inflammation but also sabotages the HSR by degrading human antigen R, a crucial mRNA-binding protein responsible for maintaining heat shock transcription factor-1 mRNA expression and stability on heat shock gene promoters. This paper underscores the imperative need to comprehend how chronic inflammation stifles the HSR and the clinical significance of evaluating the HSR using cost-effective and accessible tools. Such understanding is pivotal in the development of innovative strategies aimed at the prevention and treatment of these chronic inflammatory ailments, which continue to take a heavy toll on global health and well-being.

Cholesterol-induced HRD1 reduction accelerates vascular smooth muscle cell senescence via stimulation of endoplasmic reticulum stress-induced reactive oxygen species

Senescence of vascular smooth muscle cells (VSMCs) is a key contributor to plaque vulnerability in atherosclerosis (AS), which is affected by endoplasmic reticulum (ER) stress and reactive oxygen species (ROS) production. However, the crosstalk between ER stress and ROS production in the pathogenesis of VSMC senescence remains to be elucidated. ER-associated degradation (ERAD) is a complex process that clears unfolded or misfolded proteins to maintain ER homeostasis. HRD1 is the major E3 ligase in mammalian ERAD machineries that catalyzes ubiquitin conjugation to the unfolded or misfolded proteins for degradation. Our results showed that HRD1 protein levels were reduced in human AS plaques and aortic roots from ApoE-/- mice fed with high-fat diet (HFD), along with the increased ER stress response. Exposure to cholesterol in VSMCs activated inflammatory signaling and induced senescence, while reduced HRD1 protein expression. CRISPR Cas9-mediated HRD1 knockout (KO) exacerbated cholesterol- and thapsigargin-induced cell senescence. Inhibiting ER stress with 4-PBA (4-Phenylbutyric acid) partially reversed the ROS production and cell senescence induced by HRD1 deficiency in VSMCs, suggesting that ER stress alone could be sufficient to induce ROS production and senescence in VSMCs. Besides, HRD1 deficiency led to mitochondrial dysfunction, and reducing ROS production from impaired mitochondria partly reversed HRD1 deficiency-induced cell senescence. Finally, we showed that the overexpression of HDR1 reversed cholesterol-induced ER stress, ROS production, and cellular senescence in VSMCs. Our findings indicate that HRD1 protects against senescence by maintaining ER homeostasis and mitochondrial functionality. Thus, targeting HRD1 function may help to mitigate VSMC senescence and prevent vascular aging related diseases. TRIAL REGISTRATION: A real-world study based on the discussion of primary and secondary prevention strategies for coronary heart disease, URL:https://www.clinicaltrials.gov, the trial registration number is [2022]-02-121-01.

Cardiovascular aging: spotlight on mitochondria

Mitochondria are cellular organelles critical for ATP production and are particularly relevant to cardiovascular diseases including heart failure, atherosclerosis, ischemia-reperfusion injury, and cardiomyopathies. With advancing age, even in the absence of clinical disease, mitochondrial homeostasis becomes disrupted (e.g., redox balance, mitochondrial DNA damage, oxidative metabolism, and mitochondrial quality control). Mitochondrial dysregulation leads to the accumulation of damaged and dysfunctional mitochondria, producing excessive reactive oxygen species and perpetuating mitochondrial dysfunction. In addition, mitochondrial DNA, cardiolipin, and N-formyl peptides are potent activators of cell-intrinsic and -extrinsic inflammatory pathways. These age-related mitochondrial changes contribute to the development of cardiovascular diseases. This review covers the impact of aging on mitochondria and links these mechanisms to therapeutic implications for age-associated cardiovascular diseases.

Quercetin and dasatinib, two powerful senolytics in age-related cardiovascular disease

Cellular senescence is characteristic of the development and progression of multiple age-associated diseases. Accumulation of senescent cells in the heart contributes to various age-related pathologies. Several compounds called senolytics have been designed to eliminate these cells within the tissues. In recent years, the use and study of senolytics increased, representing a promising field for finding accessible and safe therapies for cardiovascular disease (CVD) treatment. This mini-review discusses the changes in the aging heart and the participation of senescent cells in CVD, as well as the use of senolytics to prevent the progression of myocardial damage, mainly the effect of dasatinib and quercetin. In particular, the mechanisms and physiological effects of senolytics therapies in the aged heart are discussed.

Preventing spontaneous cerebral microhemorrhages in aging mice: a novel approach targeting cellular senescence with ABT263/navitoclax

Emerging evidence from both clinical and preclinical studies underscores the role of aging in potentiating the detrimental effects of hypertension on cerebral microhemorrhages (CMHs, or cerebral microbleeds). CMHs progressively impair neuronal function and contribute to the development of vascular cognitive impairment and dementia. There is growing evidence showing accumulation of senescent cells within the cerebral microvasculature during aging, which detrimentally affects cerebromicrovascular function and overall brain health. We postulated that this build-up of senescent cells renders the aged cerebral microvasculature more vulnerable, and consequently, more susceptible to CMHs. To investigate the role of cellular senescence in CMHs' pathogenesis, we subjected aged mice, both with and without pre-treatment with the senolytic agent ABT263/Navitoclax, and young control mice to hypertension via angiotensin-II and L-NAME administration. The aged cohort exhibited a markedly earlier onset, heightened incidence, and exacerbated neurological consequences of CMHs compared to their younger counterparts. This was evidenced through neurological examinations, gait analysis, and histological assessments of CMHs in brain sections. Notably, the senolytic pre-treatment wielded considerable cerebromicrovascular protection, effectively delaying the onset, mitigating the incidence, and diminishing the severity of CMHs. These findings hint at the potential of senolytic interventions as a viable therapeutic avenue to preempt or alleviate the consequences of CMHs linked to aging, by counteracting the deleterious effects of senescence on brain microvasculature.

Navigating the landscape: Prospects and hurdles in targeting vascular smooth muscle cells for atherosclerosis diagnosis and therapy

Vascular smooth muscle cells (VSMCs) have emerged as pivotal contributors throughout all phases of atherosclerotic plaque development, effectively dispelling prior underestimations of their prevalence and significance. Recent lineage tracing studies have unveiled the clonal nature and remarkable adaptability inherent to VSMCs, thereby illuminating their intricate and multifaceted roles in the context of atherosclerosis. This comprehensive review provides an in-depth exploration of the intricate mechanisms and distinctive characteristics that define VSMCs across various physiological processes, firmly underscoring their paramount importance in shaping the course of atherosclerosis. Furthermore, this review offers a thorough examination of the significant strides made over the past two decades in advancing imaging techniques and therapeutic strategies with a precise focus on targeting VSMCs within atherosclerotic plaques, notably spotlighting meticulously engineered nanoparticles as a promising avenue. We envision the potential of VSMC-targeted nanoparticles, thoughtfully loaded with medications or combination therapies, to effectively mitigate pro-atherogenic VSMC processes. These advancements are poised to contribute significantly to the pivotal objective of modulating VSMC phenotypes and enhancing plaque stability. Moreover, our paper also delves into recent breakthroughs in VSMC-targeted imaging technologies, showcasing their remarkable precision in locating microcalcifications, dynamically monitoring plaque fibrous cap integrity, and assessing the therapeutic efficacy of medical interventions. Lastly, we conscientiously explore the opportunities and challenges inherent in this innovative approach, providing a holistic perspective on the potential of VSMC-targeted strategies in the evolving landscape of atherosclerosis research and treatment.

Treatment of advanced atherosclerotic mice with ABT-263 reduced indices of plaque stability and increased mortality

The use of senolytic agents to remove senescent cells from atherosclerotic lesions is controversial. A common limitation of previous studies is the failure to rigorously define the effects of senolytic agent ABT-263 (Navitoclax) on smooth muscle cells (SMC) despite studies claiming that these cells are the major source of senescent cells. Moreover, there are no studies on the effect of ABT-263 on endothelial cells (EC), which - along with SMC - comprise 90% of α-smooth muscle actin+ (α-SMA+) myofibroblast-like cells in the protective fibrous cap. Here we tested the hypothesis that treatment of advanced atherosclerotic mice with ABT-263 will reduce lesion size and increase plaque stability. SMC (Myh11-CreERT2-eYFP) and EC (Cdh5-CreERT2-eYFP) lineage tracing Apoe-/- mice were fed a western diet (WD) for 18 weeks, followed by ABT-263 at 100 mg/kg/bw for 6 weeks or 50 mg/kg/bw for 9 weeks. ABT-263 treatment did not change lesion size or lumen area of the brachiocephalic artery (BCA). However, ABT-263 treatment reduced SMC by 90% and increased EC contributions to lesions via EC-to-mesenchymal transition (EndoMT) by 60%. ABT-263 treatment also reduced α-SMA+ fibrous cap thickness by 60% and was associated with a > 50% mortality rate. Taken together, ABT-263 treatment of WD-fed Apoe-/- mice with advanced lesions resulted in multiple detrimental changes, including reduced indices of stability and increased mortality.

Cigarette tar accelerates atherosclerosis progression via RIPK3-dependent necroptosis mediated by endoplasmic reticulum stress in vascular smooth muscle cells

BACKGROUND

Tar is the main toxic of cigarettes, and its effect on atherosclerosis progression and the underlying mechanisms remain largely unknown. Vascular smooth muscle cells (VSMCs) play a key role in atherogenesis and plaque vulnerability. The present study sought to investigate the mechanism of atherosclerosis progression through tar-induced VSMC necroptosis, a recently described form of necrosis.

METHODS

The effect of tar on atherosclerosis progression and VSMC necroptosis was examined in ApoE-/- mice and cultured VSMCs. The role of necroptosis in tar-induced plaque development was evaluated in RIPK3-deletion mice (ApoE-/-RIPK3-/-). The key proteins of necroptosis in carotid plaques of smokers and non-smokers were also examined. Quantitative proteomics of mice aortas was conducted to further investigate the underlying mechanism. Pharmacological approaches were then applied to modulate the expression of targets to verify the regulatory process of tar-induced necroptosis.

RESULTS

Tar administration led to increased atherosclerotic plaque area and reduced collagen and VSMCs in ApoE-/- mice. The expression of RIPK1、RIPK3、and MLKL in VSMCs of plaques were all increased in tar-exposed mice and smokers. RIPK3 deletion protected against VSMC loss and plaque progression stimulated by tar. In mechanistic studies, quantitative proteomics analysis of ApoE-/- mice aortas suggested that tar triggered endoplasmic reticulum (ER) stress. PERK-eIF2α-CHOP axis was activated in tar-treated VSMCs and atherosclerotic plaque. Inhibition of ER stress using 4PBA significantly reduced plaque progression and VSMC necroptosis. Further study revealed that ER stress resulted in calcium (Ca2+) release into mitochondria and cytoplasm. Elevated Ca2+ levels lead to mitochondrial dysfunction and excessive reactive oxygen species (ROS) production, which consequently promote RIPK3-dependent necroptosis. In addition, Ca2+/calmodulin-dependent protein kinase II (CaMKII) activated by cytosolic Ca2+ overload binds to RIPK3, accounting for necroptosis.

CONCLUSION

The findings revealed that cigarette tar promoted atherosclerosis progression by inducing RIPK3-dependent VSMC necroptosis and identified novel avenues of ER stress and Ca2+ overload.

Paeonol Attenuates Atherosclerosis by Inhibiting Vascular Smooth Muscle Cells Senescence via SIRT1/P53/TRF2 Signaling Pathway

Atherosclerosis is a chronic inflammatory disease leading to various vascular diseases. Vascular smooth muscle cell (VSMC) senescence promotes atherosclerotic inflammation and the formation of plaque necrosis core, in part through telomere damage mediated by a high-fat diet. Our previous research found that paeonol, a potential anti-inflammatory agent extracted from Cortex Moutan, could significantly improve VSMCs dysfunction. However, the impact of paeonol on the senescence of VSMCs remains unexplored. This study presents the protective effects of paeonol on VSMCs senescence, and its potential activity in inhibiting the progression of atherosclerosis in vivo and in vitro. Sirtuin 1 (SIRT1) is a nuclear deacetylase involved in cell proliferation, senescence, telomere damage, and inflammation. Here, SIRT1 was identified as a potential target of paeonol having anti-senescence and anti-atherosclerosis activity. Mechanistic studies revealed that paeonol binds directly to SIRT1 and then activates the SIRT1/P53/TRF2 pathway to inhibit VSMCs senescence. Our results suggested that SIRT1-mediated VSMCs senescence is a promising druggable target for atherosclerosis, and that pharmacological modulation of the SIRT1/P53/TRF2 signaling pathway by paeonol is of potential benefit for patients with atherosclerosis.

Anti-atherosclerotic effects and molecular targets of ginkgolide B from Ginkgo biloba

Bioactive compounds derived from herbal medicinal plants modulate various therapeutic targets and signaling pathways associated with cardiovascular diseases (CVDs), the world's primary cause of death. Ginkgo biloba , a well-known traditional Chinese medicine with notable cardiovascular actions, has been used as a cardio- and cerebrovascular therapeutic drug and nutraceutical in Asian countries for centuries. Preclinical studies have shown that ginkgolide B, a bioactive component in Ginkgo biloba , can ameliorate atherosclerosis in cultured vascular cells and disease models. Of clinical relevance, several clinical trials are ongoing or being completed to examine the efficacy and safety of ginkgolide B-related drug preparations in the prevention of cerebrovascular diseases, such as ischemia stroke. Here, we present a comprehensive review of the pharmacological activities, pharmacokinetic characteristics, and mechanisms of action of ginkgolide B in atherosclerosis prevention and therapy. We highlight new molecular targets of ginkgolide B, including nicotinamide adenine dinucleotide phosphate oxidases (NADPH oxidase), lectin-like oxidized LDL receptor-1 (LOX-1), sirtuin 1 (SIRT1), platelet-activating factor (PAF), proprotein convertase subtilisin/kexin type 9 (PCSK9) and others. Finally, we provide an overview and discussion of the therapeutic potential of ginkgolide B and highlight the future perspective of developing ginkgolide B as an effective therapeutic agent for treating atherosclerosis.