Cellular Senescence Affects Cardiac Regeneration and Repair in Ischemic Heart Disease

Acetylation of FABP3 alleviates radioimmunotherapy-induced cardiomyocyte senescence by modulating long-chain polyunsaturated fatty acid metabolism

BACKGROUND

The combination of thoracic radiotherapy and immunotherapy (radioimmunotherapy) has shown significant antitumor efficacy but is associated with increased cardiotoxicity, the mechanisms of which remain poorly understood.

METHODS

A total of 72 male C57BL/6 J mice were employed to establish the radioimmunotherapy-induced cardiac injury model, with 18 mice allocated to each of four groups, including the IR group (single-dose 16 Gy cardiac irradiation), ICI group (PD-1 inhibitor 200 μg every 3 days), iRT group (16 Gy cardiac irradiation combined with PD-1 inhibitor), and Control group (IgG). Cardiac function and myocardial senescence were assessed at 28 days, 3 months, and 5 months post-intervention. Additionally, myocardial tissue transcriptomics, non-targeted metabolomics, and acetylated proteomics were performed at 28 days post-intervention, integrated with molecular experiments to investigate the mechanisms of cardiomyocyte senescence. H9C2 cardiomyocytes with FABP3 K45 acetylation-mimetic (K45Q), empty vector (EV), and non-acetylatable (K45R) mutant were used for functional validation.

RESULTS

Combined radioimmunotherapy significantly exacerbated cardiac dysfunction and cardiomyocyte senescence in murine models, manifested with elevated serum levels of cardiac injury biomarkers of cTnI and NT-proBNP, reduced LVEF and LVFS, aggravated myocardial histopathological changes characterized by enhanced inflammatory infiltration, interstitial edema, and myocardium structure disorder in iRT group compared to the other three groups. Concomitantly, compared with other groups, the senescence-associated markers (p16, p21, and SASP factors) in the myocardial tissues of the iRT group were markedly upregulated from 28 days to 5 months. By integrating transcriptomic and non-targeted metabolomics analyses, as well as molecular experiments, we revealed that radioimmunotherapy resulted in dysregulated myocardial metabolism by suppressing ATP production, promoting lipid droplet accumulation, mitochondrial dysfunction, and fatty acid metabolism alterations, particularly involving long-chain polyunsaturated fatty acid (PUFAs) metabolism. Acetylome profiling identified a significant increase in FABP3 K45 acetylation (log2FC = 8.73, P < 0.05) in iRT vs. Control group, with acute-phase elevation (28 days, P < 0.001) and chronic-phase reduction (3 months, P < 0.001). Functional validation in H9C2 cardiomyocytes demonstrated that, compared to EV and K45R groups, FABP3 K45Q attenuated cellular senescence, enhanced mitochondrial oxidative phosphorylation, fatty acid metabolism, and ATP production, while attenuated ROS generation, lipid droplet accumulation, and glycolysis. Metabolomic analysis also revealed the acetylation of FABP3 K45 was significantly associated with the synthesis or accumulation of PUFAs, such as arachidonic acid and linoleic acid, which may alleviate cardiomyocyte senescence by enhancing energy supply and blocking the synthesis of inflammatory mediators.

CONCLUSION

FABP3 K45 acetylation mitigates radioimmunotherapy-induced cardiomyocyte senescence and metabolic dysfunction, revealing a novel regulatory mechanism that links post-translational modifications to cardiac cellular homeostasis under combined radioimmunotherapy.

Inhibiting the Histone Demethylase Kdm4a Restrains Cardiac Fibrosis After Myocardial Infarction by Promoting Autophagy in Premature Senescent Fibroblasts

Premature senescent fibroblasts (PSFs) play an important role in regulating the fibrotic process after myocardial infarction (MI), but their effect on cardiac fibrosis remains unknown. Here, the investigation is aimed to determine whether PSFs contribute to cardiac fibrosis and the underlying mechanisms involved. It is observed that premature senescence of fibroblasts is strongly activated in the injured myocardium at 7 days after MI and identified that Kdm4a is located in PSFs by the analysis of scRNA-seq data and immunostaining staining. Moreover, fibroblast specific gain- and loss-of-function assays showed that Kdm4a promoted the premature senescence of fibroblasts and cardiac interstitial fibrosis, contributing to cardiac remodeling in the advanced stage after MI, without influencing early cardiac rupture. ChIP-seq and ChIP-PCR revealed that Kdm4a deficiency promoted autophagy in PSFs by reducing Trim44 expression through increased levels of the H3K9me3 modification in the Trim44 promoter region. Furthermore, a coculture system revealed that Kdm4a overexpression increased the accumulation of PSFs and the secretion of senescence-associated secretory phenotype (SASP) factors, subsequently inducing cardiac fibrosis, which could be reversed by Trim44 interference. Kdm4a induces the premature senescence of fibroblasts through Trim44-mediated autophagy and then facilitates interstitial fibrosis after MI, ultimately resulting in cardiac remodeling, but not affecting ventricular rupture.

Young fibroblast-derived migrasomes alleviate keratinocyte senescence and enhance wound healing in aged skin

BACKGROUND

Alterations in intercellular communication driven by cellular senescence constitute an important factor in skin aging. Migrasome, a newly discovered vesicular organelle, efficiently participates in intercellular communication; however, the relationship between cellular senescence and migrasomes remains unreported.

OBJECTIVE

This study aims to explore the possible relationship between cellular senescence and migrasomes formation, and investigate the effects of young fibroblast-derived migrasomes on senescent keratinocytes and wound healing in aged skin.

RESULT

Single-cell RNA sequencing (scRNA-seq) data analysis revealed that fibroblasts exhibited the highest level of transcriptional variability during skin aging, and the degree of fibroblast senescence negatively correlated with the expression level of migrasome-associated markers. Further multiplex Immunohistochemistry (mIHC) results suggested that younger mouse skin contained more migrasomes than older mouse skin. Transmission electron microscopy (TEM) observations demonstrated abundant migrasomes in the skin from young individuals. In vitro experiments indicated that young fibroblasts produced significantly more migrasomes than senescent fibroblasts, as confirmed by wheat germ agglutinin (WGA) staining and scanning electron microscopy (SEM). Importantly, purified migrasomes from young fibroblasts were found to reduce the expression of senescence-associated markers in HaCaT cells. In vivo, using a wound healing model in naturally aged mice, we observed that migrasomes derived from young fibroblasts not only accelerated wound healing but also reduced senescence-associated marker expression in the skin.

CONCLUSION

Migrasomes formation ability reduced during skin aging progress, and young fibroblast-derived migrasomes rejuvenated senescent keratinocytes and promoted wound healing in aged skin. These findings offer new ideas for alleviating skin aging and enhancing wound healing in aged skin.

Injectable Senolytic Hydrogel Depot for the Clearance of Senescent Cells

Small molecules are frontline therapeutics for many diseases; however, they are often limited by their poor solubility. Therefore, hydrophobic small molecules are often encapsulated or prepared as pure drug nanoparticles. Navitoclax, used to eliminate senescent cells, is one such small molecule that faces challenges in translation due to its hydrophobicity and toxic side effects. Further, as senescent cells exhibit context-dependent pathologic or beneficial properties, it is preferable to eliminate senescent cells locally. To formulate navitoclax and enable local treatment, we designed an injectable hydrogel loaded with navitoclax nanoparticles as a senolytic delivery vehicle. Navitoclax nanoparticles (Ø ∼ 110 nm) were prepared via solvent-antisolvent nanoprecipitation and formulated in an injectable polymer-nanoparticle (PNP) hydrogel to create a local senolytic depot. Navitoclax-loaded PNP hydrogels selectively cleared senescent cells in vitro in senescent endothelial monolayers. This work demonstrates the value of formulating lipophilic small molecules and the potential of localized drug delivery strategies to improve senolytic therapies.

Multi-Omics Analysis of Aberrances and Functional Implications of IRF5 in Digestive Tract Tumours

Oesophageal cancer (EC) is a common gastrointestinal malignancy and includes oesophageal squamous cell carcinoma (ESCC) and oesophageal adenocarcinoma (EAC) sub-types. Gene signatures predicting patient outcomes are not routinely used in clinical practice, particularly owing to batch effects and data standardisation. Here, we sought to establish and validate a reliable signature of senescence-related genes (SRGs) that would aid in predicting prognosis in patients with EC. We downloaded transcriptomics data, and a novel pairwise comparison algorithm selected valid SRG pairs (SRGPs) to construct a prognostic SRGP signature. The SRGPs were verified using Kaplan-Meier survival and receiver operating characteristic curve analyses. Additionally, the relationships between the SRGP signatures and prognosis, immune cell infiltration and chemotherapeutic drug responsiveness were evaluated. The random forest algorithm identified the most clinically significant genes, followed by experimental validation. 19 and 26 SRGP signatures were created for ESCC (n = 81) and EAC (n = 79), respectively. Patients with EC were divided into two groups based on the median risk score. The Kaplan-Meier analysis demonstrated significant differences in overall survival between the ESCC and EAC groups (p < 0.001). The sub-types exhibited different immune signatures. IRF5 was the most clinically significant gene for ESCC. It was highly expressed in ESCC cells, and IRF5 knockdown inhibited cell migration and proliferation, while promoting apoptosis and senescence. The SRGP signature may predict prognosis and immunotherapeutic responses, and IRF5 is a potential target gene for ESCC.

Assessment of cardiovascular risk and physical activity: the role of cardiac-specific biomarkers in the general population and athletes

The first part of this Inter-Society Document describes the mechanisms involved in the development of cardiovascular diseases, particularly arterial hypertension, in adults and the elderly. It will also examine how consistent physical exercise during adolescence and adulthood can help maintain blood pressure levels and prevent progression to symptomatic heart failure. The discussion will include experimental and clinical evidence on the use of specific exercise programs for preventing and controlling cardiovascular diseases in adults and the elderly. In the second part, the clinical relevance of cardiac-specific biomarkers in assessing cardiovascular risk in the general adult population will be examined, with a focus on individuals engaged in sports activities. This section will review recent studies that suggest a significant role of biomarkers in assessing cardiovascular risk, particularly the presence of cardiac damage, in athletes who participate in high-intensity sports. Finally, the document will discuss the potential of using cardiac-specific biomarkers to monitor the effectiveness of personalized physical activity programs (Adapted Physical Activity, APA). These programs are prescribed for specific situations, such as chronic diseases or physical disabilities, including cardiovascular diseases. The purposes of this Inter-Society Document are the following: 1) to discuss the close pathophysiological relationship between physical activity levels (ranging from sedentary behavior to competitive sports), age categories (from adolescence to elderly age), and the development of cardiovascular diseases; 2) to review in detail the experimental and clinical evidences supporting the role of cardiac biomarkers in identifying athletes and individuals of general population at higher cardiovascular risk; 3) to stimulate scientific societies and organizations to develop specific multicenter studies that may take into account the role of cardiac biomarkers in subjects who follow specific exercise programs in order to monitor their cardiovascular risk.

Targeting senescence and GATA4 in age-related cardiovascular disease: a comprehensive approach

The growing prevalence of age-related cardiovascular diseases (CVDs) poses significant health challenges, necessitating the formulation of novel treatment approaches. GATA4, a vital transcription factor identified for modulating cardiovascular biology and cellular senescence, is recognized for its critical involvement in CVD pathogenesis. This review collected relevant studies from PubMed, Google Scholar, and Science Direct using search terms like 'GATA4,' 'cellular senescence,' 'coronary artery diseases,' 'hypertension,' 'heart failure,' 'arrhythmias,' 'congenital heart diseases,' 'cardiomyopathy,' and 'cardiovascular disease.' Additionally, studies investigating the molecular mechanisms underlying GATA4-mediated regulation of GATA4 and senescence in CVDs were analyzed to provide comprehensive insights into this critical aspect of potential treatment targeting. Dysregulation of GATA4 is involved in a variety of CVDs, as demonstrated by both experimental and clinical research, comprising CAD, hypertension, congenital heart diseases, cardiomyopathy, arrhythmias, and cardiac insufficiency. Furthermore, cellular senescence enhances the advancement of age-related CVDs. These observations suggested that therapies targeting GATA4, senescence pathways, or both as necessary may be an effective intervention in CVD progression and prognosis. Addressing age-related CVDs by targeting GATA4 and senescence is a broad mechanism approach. It implies further investigation of the molecular nature of these processes and elaboration of an effective therapeutic strategy. This review highlights the importance of GATA4 and senescence in CVD pathogenesis, emphasizing their potential as therapeutic targets for age-related CVDs.

The role of cardiomyocyte senescence in cardiovascular diseases: A molecular biology update

Cardiovascular diseases (CVD) are the leading cause of death worldwide, and advanced age is a main contributor to the prevalence of CVD. Cellular senescence is an irreversible state of cell cycle arrest that occurs in old age or after cells encounter various stresses. Senescent cells not only result in the reduction of cellular function, but also produce senescence-associated secretory phenotype (SASP) to affect surrounding cells and tissue microenvironment. There is increasing evidence that the gradual accumulation of senescent cardiomyocytes is causally involved in the decline of cardiovascular system function. To highlight the role of senescent cardiomyocytes in the pathophysiology of age-related CVD, we first introduced that senescent cardiomyoyctes can be identified by structural changes and several senescence-associated biomarkers. We subsequently provided a comprehensive summary of existing knowledge, outlining the compelling evidence on the relationship between senescent cardiomyocytes and age-related CVD phenotypes. In addition, we discussed that the significant therapeutic potential represented by the prevention of accelerated senescent cardiomyocytes, and the current status of some existing geroprotectors in the prevention and treatment of age-related CVD. Together, the review summarized the role of cardiomyocyte senescence in CVD, and explored the molecular knowledge of senescent cardiomyocytes and their potential clinical significance in developing senescent-based therapies, thereby providing important insights into their biology and potential therapeutic exploration.

The potential of flavonoids to mitigate cellular senescence in cardiovascular disease

Aging is one of the most significant factors affecting cardiovascular health, with cellular senescence being a central hallmark. Senescent cells (SCs) secrete a specific set of signaling molecules known as the senescence-associated secretory phenotype (SASP). The SASP has a remarkable impact on age-associated diseases, particularly cardiovascular diseases (CVD). Targeting SCs through anti-aging therapies represents a novel strategy to effectively retard senescence and attenuate disease progression. Accumulating evidence demonstrates that the flavonoids, widely presented in fruits and vegetables worldwide, can delay or treat CVD via selectively eliminating SCs (senolytics) and modulating SASPs (senomorphics). Nevertheless, only sporadic research has illustrated the application of flavonoids in targeting SCs for CVD, which requires further exploration. This review recapitulates the hallmarks and key molecular mechanisms involved in cellular senescence, then summarizes senescence of different types of cardiac cells and describes the mechanisms by which cellular senescence affects CVD development. The discussion culminates with the potential use of flavonoids via exerting their biological effects on cellular senescence to reduce CVD incidence. This summary will provide valuable insights for cardiovascular drug design, development and clinical applications leveraging flavonoids.

Peptide-Amphiphilic Nanoassemblies as a Responsive Senolytic Navigator for Targeted Removal of Senescent Cardiomyocytes to Ameliorate Heart Failure

Heart failure (HF) represents the terminal stage of numerous cardiovascular disorders and lacks effective therapeutic strategies. The accumulation of senescent cardiomyocytes is a cardinal characteristic of HF, contributing to myocardial dysfunction and deteriorating the myocardial microenvironment through the development of senescence-associated secretory phenotypes (SASPs), ultimately culminating in pathological remodeling. Senolytics, a promising therapeutic strategy that selectively induces apoptosis in senescent cells, faces challenges due to nonspecific effects, raising concerns for clinical implementation. In this study, we developed peptide-amphiphilic nanoassemblies as responsive drug navigators for targeted delivery. The modular nanoassemblies comprise a hydrophilic domain containing a CD9-binding peptide, a hydrophobic domain incorporating a reactive oxygen species (ROS)-responsive motif, and an alkyl tail for encapsulation of the senolytic ABT263. The CD9-targeted and ROS-responsive nanoassemblies (AP@ABT263) specifically recognized senescent cardiomyocytes and modulated the release of ABT263 in the presence of elevated intracellular ROS levels. AP@ABT263 treatment significantly enhanced the targeted delivery of ABT263 to senescent cells in both in vitro and in vivo while showing minimal toxicity to normal cardiomyocytes and other tissues. Our findings provide compelling evidence that AP@ABT263 efficiently eradicated senescent cardiomyocytes, enhanced cardiac function, and attenuated the deleterious effects of SASP, thereby preventing adverse cardiac remodeling. In summary, AP@ABT263 represents a highly promising approach for responsive and controlled drug release in senescent cardiomyocytes, providing valuable insights into the development of intelligent pharmaceutical interventions for the management of HF.

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.

Identification and validation of aging-related genes in heart failure based on multiple machine learning algorithms

Background

In the face of continued growth in the elderly population, the need to understand and combat age-related cardiac decline becomes even more urgent, requiring us to uncover new pathological and cardioprotective pathways.

Methods

We obtained the aging-related genes of heart failure through WGCNA and CellAge database. We elucidated the biological functions and signaling pathways involved in heart failure and aging through GO and KEGG enrichment analysis. We used three machine learning algorithms: LASSO, RF and SVM-RFE to further screen the aging-related genes of heart failure, and fitted and verified them through a variety of machine learning algorithms. We searched for drugs to treat age-related heart failure through the DSigDB database. Finally, We use CIBERSORT to complete immune infiltration analysis of aging samples.

Results

We obtained 57 up-regulated and 195 down-regulated aging-related genes in heart failure through WGCNA and CellAge databases. GO and KEGG enrichment analysis showed that aging-related genes are mainly involved in mechanisms such as Cellular senescence and Cell cycle. We further screened aging-related genes through machine learning and obtained 14 key genes. We verified the results on the test set and 2 external validation sets using 15 machine learning algorithm models and 207 combinations, and the highest accuracy was 0.911. Through screening of the DSigDB database, we believe that rimonabant and lovastatin have the potential to delay aging and protect the heart. The results of immune infiltration analysis showed that there were significant differences between Macrophages M2 and T cells CD8 in aging myocardium.

Conclusion

We identified aging signature genes and potential therapeutic drugs for heart failure through bioinformatics and multiple machine learning algorithms, providing new ideas for studying the mechanism and treatment of age-related cardiac decline.

The Senescent Heart-"Age Doth Wither Its Infinite Variety"

Cardiovascular diseases are a leading cause of morbidity and mortality world-wide. While many factors like smoking, hypertension, diabetes, dyslipidaemia, a sedentary lifestyle, and genetic factors can predispose to cardiovascular diseases, the natural process of aging is by itself a major determinant of the risk. Cardiac aging is marked by a conglomerate of cellular and molecular changes, exacerbated by age-driven decline in cardiac regeneration capacity. Although the phenotypes of cardiac aging are well characterised, the underlying molecular mechanisms are far less explored. Recent advances unequivocally link cardiovascular aging to the dysregulation of critical signalling pathways in cardiac fibroblasts, which compromises the critical role of these cells in maintaining the structural and functional integrity of the myocardium. Clearly, the identification of cardiac fibroblast-specific factors and mechanisms that regulate cardiac fibroblast function in the senescent myocardium is of immense importance. In this regard, recent studies show that Discoidin domain receptor 2 (DDR2), a collagen-activated receptor tyrosine kinase predominantly located in cardiac fibroblasts, has an obligate role in cardiac fibroblast function and cardiovascular fibrosis. Incisive studies on the molecular basis of cardiovascular aging and dysregulated fibroblast function in the senescent heart would pave the way for effective strategies to mitigate cardiovascular diseases in a rapidly growing elderly population.

The structure and function of lamin A/C: Special focus on cardiomyopathy and therapeutic interventions

Lamins are inner nuclear membrane proteins that belong to the intermediate filament family. Lamin A/C lie adjacent to the heterochromatin structure in polymer form, providing skeletal to the nucleus. Based on the localization, lamin A/C provides nuclear stability and cytoskeleton to the nucleus and modulates chromatin organization and gene expression. Besides being the structural protein making the inner nuclear membrane in polymer form, lamin A/C functions as a signalling molecule involved in gene expression as an enhancer inside the nucleus. Lamin A/C regulates various cellular pathways like autophagy and energy balance in the cytoplasm. Its expression is highly variable in differentiated tissues, higher in hard tissues like bone and muscle cells, and lower in soft tissues like the liver and brain. In muscle cells, including the heart, lamin A/C must be expressed in a balanced state. Lamin A/C mutation is linked with various diseases, such as muscular dystrophy, lipodystrophy, and cardiomyopathies. It has been observed that a good number of mutations in the LMNA gene impact cardiac activity and its function. Although several works have been published, there are still several unexplored areas left regarding the lamin A/C function and structure in the cardiovascular system and its pathological state. In this review, we focus on the structural organization, expression pattern, and function of lamin A/C, its interacting partners, and the pathophysiology associated with mutations in the lamin A/C gene, with special emphasis on cardiovascular diseases. With the recent finding on lamin A/C, we have summarized the possible therapeutic interventions to treat cardiovascular symptoms and reverse the molecular changes.

The pro-resolving mediator, annexin A1 regulates blood pressure, and age-associated changes in cardiovascular function and remodeling

Aging is associated with chronic, low-level inflammation which may contribute to cardiovascular pathologies such as hypertension and atherosclerosis. This chronic inflammation may be opposed by endogenous mechanisms to limit inflammation, for example, by the actions of annexin A1 (ANXA1), an endogenous glucocorticoid-regulated protein that has anti-inflammatory and pro-resolving activity. We hypothesized the pro-resolving mediator ANXA1 protects against age-induced changes in blood pressure (BP), cardiovascular structure and function, and cardiac senescence. BP was measured monthly in conscious mature (4-month) and middle-aged (12-month) ANXA1-deficient (ANXA1-/- ) and wild-type C57BL/6 mice. Body composition was measured using EchoMRI, and both cardiac and vascular function using ultrasound imaging. Cardiac hypertrophy, fibrosis and senescence, vascular fibrosis, elastin, and calcification were assessed histologically. Gene expression relevant to structural remodeling, inflammation, and cardiomyocyte senescence were also quantified. In C57BL/6 mice, progression from 4 to 12 months of age did not affect the majority of cardiovascular parameters measured, with the exception of mild cardiac hypertrophy, vascular calcium, and collagen deposition. Interestingly, ANXA1-/- mice exhibited higher BP, regardless of age. Additionally, age progression had a marked impact in ANXA1-/- mice, with markedly augmented vascular remodeling, impaired vascular distensibility, and body composition. Consistent with vascular dysfunction, cardiac dysfunction, and hypertrophy were also evident, together with markers of senescence and inflammation. These findings suggest that endogenous ANXA1 plays a critical role in regulating BP, cardiovascular function, and remodeling and delays cardiac senescence. Our findings support the development of novel ANXA1-based therapies to prevent age-related cardiovascular pathologies.

Cardiac cell senescence: molecular mechanisms, key proteins and therapeutic targets

Cardiac aging, particularly cardiac cell senescence, is a natural process that occurs as we age. Heart function gradually declines in old age, leading to continuous heart failure, even in people without a prior history of heart disease. To address this issue and improve cardiac cell function, it is crucial to investigate the molecular mechanisms underlying cardiac senescence. This review summarizes the main mechanisms and key proteins involved in cardiac cell senescence. This review further discusses the molecular modulators of cellular senescence in aging hearts. Furthermore, the discussion will encompass comprehensive descriptions of the key drugs, modes of action and potential targets for intervention in cardiac senescence. By offering a fresh perspective and comprehensive insights into the molecular mechanisms of cardiac senescence, this review seeks to provide a fresh perspective and important theoretical foundations for the development of drugs targeting this condition.

lncRNA JPX-Enriched Chromatin Microenvironment Mediates Vascular Smooth Muscle Cell Senescence and Promotes Atherosclerosis

BACKGROUND

Senescence is a series of degenerative changes in the structure and physiological function of an organism. Whether JPX (just proximal to XIST)-a newly identified age-related noncoding RNA by us-is associated with atherosclerosis is still unknown. Our study was to investigate the role of JPX and provide insights into potential therapies targeting atherosclerosis.

METHODS

We analyzed clinical data from multiple tissues including meniscus tissue, leukemia cells, and peripheral blood monocytes to identify age-related noncoding RNAs in senescent vascular smooth muscle cells (VSMCs). The molecular mechanism of JPX was investigated by capture hybridization analysis of RNA targets and chromatin immunoprecipitation. IGVTools and real-time quantitative polymerase chain reaction were used to evaluate the JPX expression during phenotype regulation in age-related disease models. The therapeutic potential of JPX was evaluated after establishing an atherosclerosis model in smooth muscle-specific Jpx knockout mice.

RESULTS

JPX expression was upregulated in activated ras allele (H-rasV12)-induced senescent VSMCs and atherosclerotic arteries. JPX knockdown substantially reduced the elevation of senescence-associated secretory phenotype (SASP) genes in senescent VSMCs. Cytoplasmic DNA leaked from mitochondria via mitochondrial permeability transition pore formed by VDAC1 (voltage-dependent anion channel 1) oligomer activates the STING (stimulator of interferon gene) pathway. JPX could act as an enhancer for the SASP genes and functions as a scaffold molecule through interacting with phosphorylated p65/RelA and BRD4 (bromodomain-containing protein 4) in chromatin remodeling complex, promoting the transcription of SASP genes via epigenetic regulation. Smooth muscle knockout of Jpx in ApoeKO mice resulted in a decrease in plaque area, a reduction in SASP gene expression, and a decrease in senescence compared with controls.

CONCLUSIONS

As an enhancer RNA, JPX can integrate p65 and BRD4 to form a chromatin remodeling complex, activating SASP gene transcription and promoting cellular senescence. These findings suggest that JPX is a potential therapeutic target for the treatment of age-related atherosclerosis.

Identification and exploration of aging-related subtypes and distinctive role of SERPINE1 in heart failure based on single-cell and bulk RNA sequencing data

Aging is a major risk factor for heart failure (HF) and is the leading cause of death worldwide. Currently, the nature of the relationship between aging and HF is not entirely clear. Herein, this study aimed to explore new diagnostic biomarkers, molecular typing and therapeutic strategies for HF by investigating the biological significance of aging-related genes in HF. A total of 157 differentially expressed genes (DEGs) were screened totally between HF and normal samples, and functional enrichment analysis of DEGs revealed the strong association of HF progression with aging, immune processes and metabolism. Six HF-specific aging-related genes were further identified, and a diagnostic model was developed and validated for good diagnostic efficacy. In addition, we collected blood samples from 10 normal controls and 10 HF patients for RT-qPCR analysis to verify the bioinformation. We also identified two aging-associated subtypes with distinctly different immune infiltration and metabolic microenvironment. Further single-cell sequencing analysis conducted in the study identified SERPINE1 as a key gene in HF. The distinctive role of SERPINE1 fibroblasts was revealed, including three main findings: (I) fibroblasts had a higher proportion and expression of SERPINE1 levels in HF; (II) the ligand-receptor pair MDK-LRP1 made the most contributions in high interactions with other cell types in SERPINE1 fibroblasts; and (III) SERPINE1 fibroblasts were associated with the interaction of extracellular matrix and receptor and may be regulated by the transcription factor EGR1. In conclusion, this study highlights the importance of aging-related genes in diagnosing HF and regulating immune infiltration. We also identified different HF subtypes and a potentially crucial gene, which may provide a better understanding of the molecular-level mechanisms of aging-related HF and aid in developing effective therapeutic strategies.

The Binding of HSPA8 and Mitochondrial ALDH2 Mediates Oxygen-Glucose Deprivation-Induced Fibroblast Senescence

Cellular senescence refers to the permanent and irreversible cessation of the cell cycle. Recently, it has gained significant interest as a promising target for preventing cardiovascular diseases. Aldehyde dehydrogenase 2 (ALDH2) is a mitochondrial enzyme that has been closely linked with an increased risk of cardiovascular diseases. In this study, bioinformatics analysis revealed that the signaling pathway for fibroblast senescence is significantly activated in mice after myocardial infarction (MI), and that ALDH2 might be a crucial molecule responsible for inducing this change. Therefore, we created an NIH3T3 fibroblast cell line oxygen-glucose deprivation (OGD) model to replicate the conditions of MI in vitro. We further revealed that decreased ALDH2 enzyme activity is a critical factor that affects fibroblast senescence after OGD, and the activation of ALDH2 can improve the mitochondrial damage caused by OGD. We identified Heat Shock 70-kDa Protein 8 (HSPA8) as an interacting protein of ALDH2 through co-immunoprecipitation (Co-IP) and mass spectrometry (MS) detection. Subsequently, our studies showed that HSPA8 translocates to the mitochondria after OGD, potentially binding to ALDH2 and inhibiting its enzyme activity. By transfecting siRNA to inhibit HSPA8 expression in cells, it was found that ALDH2 enzyme activity can be significantly increased, and the senescence characteristics induced by OGD in NIH3T3 cells can be improved. In conclusion, the data from this study suggest that HSPA8, in conjunction with ALDH2, could regulate fibroblast senescence after oxygen-glucose deprivation, providing a new direction and foundation for effectively intervening in fibroblast senescence after myocardial infarction.

What Links Chronic Kidney Disease and Ischemic Cardiomyopathy? A Comprehensive Bioinformatic Analysis Utilizing Bulk and Single-Cell RNA Sequencing Data with Machine Learning

Chronic kidney disease (CKD) emerges as a substantial contributor to various cardiovascular disorders, including ischemic cardiomyopathy (ICM). However, the underlying molecular mechanisms linking CKD and ICM remain elusive. Our study aims to unravel these connections by integrating publicly available bulk and single-cell RNA sequencing (scRNA-seq) data. Expression profiles from two ICM datasets obtained from heart tissue and one CKD with Peripheral Blood Mononuclear Cell (CKD-PBMC) dataset were collected. We initiated by identifying shared differentially expressed genes (DEGs) between ICM and CKD. Subsequent functional enrichment analysis shed light on the mechanisms connecting CKD to ICM. Machine learning algorithms enabled the identification of 13 candidate genes, including AGRN, COL16A1, COL1A2, FAP, FRZB, GPX3, ITIH5, NFASC, PTN, SLC38A1, STARD7, THBS2, and VPS35. Their expression patterns in ICM were investigated via scRNA-seq data analysis. Notably, most of them were enriched in fibroblasts. COL16A1, COL1A2, PTN, and FAP were enriched in scar-formation fibroblasts, while GPX3 and THBS2 showed enrichment in angiogenesis fibroblasts. A Gaussian naïve Bayes model was developed for diagnosing CKD-related ICM, bolstered by SHapley Additive exPlanations interpretability and validated internally and externally. In conclusion, our investigation unveils the extracellular matrix's role in CKD and ICM interplay, identifies 13 candidate genes, and showcases their expression patterns in ICM. We also constructed a diagnostic model using 13 gene features and presented an innovative approach for managing CKD-related ICM through serum-based diagnostic strategies.

Identification and functional analysis of senescent cells in the cardiovascular system using omics approaches

Cardiovascular disease (CVD) is a leading cause of morbidity and mortality worldwide, and senescent cells have emerged as key contributors to its pathogenesis. Senescent cells exhibit cell cycle arrest and secrete a range of proinflammatory factors, termed the senescence-associated secretory phenotype (SASP), which promotes tissue dysfunction and exacerbates CVD progression. Omics technologies, specifically transcriptomics and proteomics, offer powerful tools to uncover and define the molecular signatures of senescent cells in cardiovascular tissue. By analyzing the comprehensive molecular profiles of senescent cells, omics approaches can identify specific genetic alterations, gene expression patterns, protein abundances, and metabolite levels associated with senescence in CVD. These omics-based discoveries provide insights into the mechanisms underlying senescence-induced cardiovascular damage, facilitating the development of novel diagnostic biomarkers and therapeutic targets. Furthermore, integration of multiple omics data sets enables a systems-level understanding of senescence in CVD, paving the way for precision medicine approaches to prevent or treat cardiovascular aging and its associated complications.

DNA Methylation and Telomeres-Their Impact on the Occurrence of Atrial Fibrillation during Cardiac Aging

Atrial fibrillation (AF) is the most common arrhythmia in humans. AF is characterized by irregular and increased atrial muscle activation. This high-frequency activation obliterates the synchronous work of the atria and ventricles, reducing myocardial performance, which can lead to severe heart failure or stroke. The risk of developing atrial fibrillation depends largely on the patient's history. Cardiovascular diseases are considered aging-related pathologies; therefore, deciphering the role of telomeres and DNA methylation (mDNA), two hallmarks of aging, is likely to contribute to a better understanding and prophylaxis of AF. In honor of Prof. Elizabeth Blackburn's 75th birthday, we dedicate this review to the discovery of telomeres and her contribution to research on aging.

Differences in Leukocyte Transcriptomes of Morbidly Obese Patients With High Output Heart Failure: A Pilot Study

Background and Objectives

Heart failure is characterized by alterations of gene expression that provide insight into the underlying pathophysiologic mechanisms. However, obesity-related high output heart failure (HOHF) is a specific phenotype of heart failure that has not been studied using gene expression. Our aim in this study was to examine the variances in leukocyte transcriptomes of morbidly obese patients with HOHF.

Methods

In this cross-sectional study, we applied stranded total RNA-sequencing to six patients with morbid obesity and HOHF and 6 patients with morbid obesity and non-HOHF. Differential gene expression was calculated, and Ingenuity Pathway Analysis software was used to interpret the canonical pathways, functional changes, upstream regulators, and networks in these patients.

Results

We found in patients with HOHF that there were 116 differentially expressed genes with upregulation of 114 genes and downregulation of 2 genes. The differentially expressed genes were involved with cell proliferation, mitochondrial function, erythropoiesis, erythrocyte stability, and apoptosis. The top upregulated canonical pathways associated with differentially expressed genes were autophagy, adenosine monophosphate-activated protein kinase signaling, and senescence pathways. We identified GATA binding protein 1 as an upstream regulator and nuclear factor kappa-light-chain-enhancer of activated B cells associated network.

Conclusions

We are the first to report the differential gene expression in patients with obesity-related HOHF and reveal the various pathophysiologic mechanisms underlying the disease. Further research is needed to determine the role of cellular function and maintenance, inflammation, and iron homeostasis in obesity-related HOHF.

Identification of senescence-related lncRNA prognostic index correlating with prognosis and radiosensitivity in prostate cancer patients

BACKGROUND

An increasing number of studies are shown how crucial a role cellular senescence plays in tumor development. In this study, we developed a senescence-related lncRNA prognostic index (SRLPI) to forecast radiosensitivity and the probability of biochemical recurrence (BCR) in patients with prostate cancer (PCa).

METHODS

PCa cohorts in TCGA and GEO databases were downloaded. Senescence-and prognosis-related lncRNA with differential expression in tumor and normal samples were identified and used to establish the SRLPI score. Mutation landscape, function pathway, tumor stemness and heterogeneity and tumor immune microenvironment were also analyzed. We performed the analysis using R 3.6.3 and the appropriate tools.

RESULTS

A SRLPI score was constructed based on SNHG1 and MIAT in the TCGA cohort. Our classification of PCa patients into high- and low-risk groups was based on the median SRLPI score. When compared to the low-SRLPI group, the high-SRLPI group was more vulnerable to BCR (HR: 3.33). In terms of BCR-free survival and metastasis-free survival, the GSE116918 showed similar findings. Surprisingly, the SRLPI score demonstrated a high level of radiosensitivity for diagnosis (AUC: 0.98). Age, Gleason score, T stage, N stage, positive lymph nodes, and residual tumor were all significantly greater in patients with high SRLPI scores. Furthermore, this score was significantly related to markers of senescence. Protein secretion and androgen response were found to be substantially enriched in the low-SRLPI group, whereas E2F targets were found to be strongly enriched in the high-SRLPI group for pathway analysis. For the tumor microenvironment assessment, B cells, CD8+ T cells, immune score and TIDE score were positively related to SRLPI score while endothelial level was negatively associated with SRLPI score with statistical significance.

CONCLUSIONS

We developed a SRLPI score that was related to prognosis and radiosensitivity and might be helpful in clinical practice.

Identification of crucial genes related to heart failure based on GEO database

BACKGROUND

The molecular biological mechanisms underlying heart failure (HF) remain poorly understood. Therefore, it is imperative to use innovative approaches, such as high-throughput sequencing and artificial intelligence, to investigate the pathogenesis, diagnosis, and potential treatment of HF.

METHODS

First, we initially screened Two data sets (GSE3586 and GSE5406) from the GEO database containing HF and control samples from the GEO database to establish the Train group, and selected another dataset (GSE57345) to construct the Test group for verification. Next, we identified the genes with significantly different expression levels in patients with or without HF and performed functional and pathway enrichment analyses. HF-specific genes were identified, and an artificial neural network was constructed by Random Forest. The ROC curve was used to evaluate the accuracy and reliability of the constructed model in the Train and Test groups. Finally, immune cell infiltration was analyzed to determine the role of the inflammatory response and the immunological microenvironment in the pathogenesis of HF.

RESULTS

In the Train group, 153 significant differentially expressed genes (DEGs) associated with HF were found to be abnormal, including 81 down-regulated genes and 72 up-regulated genes. GO and KEGG enrichment analyses revealed that the down-regulated genes were primarily enriched in organic anion transport, neutrophil activation, and the PI3K-Akt signaling pathway. The upregulated genes were mainly enriched in neutrophil activation and the calcium signaling. DEGs were identified using Random Forest, and finally, 16 HF-specific genes were obtained. In the ROC validation and evaluation, the area under the curve (AUC) of the Train and Test groups were 0.996 and 0.863, respectively.

CONCLUSIONS

Our research revealed the potential functions and pathways implicated in the progression of HF, and designed an RNA diagnostic model for HF tissues using machine learning and artificial neural networks. Sensitivity, specificity, and stability were confirmed by ROC curves in the two different cohorts.

RANKL+ senescent cells under mechanical stress: a therapeutic target for orthodontic root resorption using senolytics

In dentistry, orthodontic root resorption is a long-lasting issue with no effective treatment strategy, and its mechanisms, especially those related to senescent cells, remain largely unknown. Here, we used an orthodontic intrusion tooth movement model with an L-loop in rats to demonstrate that mechanical stress-induced senescent cells aggravate apical root resorption, which was prevented by administering senolytics (a dasatinib and quercetin cocktail). Our results indicated that cementoblasts and periodontal ligament cells underwent cellular senescence (p21⁺ or p16⁺) and strongly expressed receptor activator of nuclear factor-kappa B (RANKL) from day three, subsequently inducing tartrate-resistant acid phosphatase (TRAP)-positive odontoclasts and provoking apical root resorption. More p21⁺ senescent cells expressed RANKL than p16⁺ senescent cells. We observed only minor changes in the number of RANKL⁺ non-senescent cells, whereas RANKL⁺ senescent cells markedly increased from day seven. Intriguingly, we also found cathepsin K⁺p21⁺p16⁺ cells in the root resorption fossa, suggesting senescent odontoclasts. Oral administration of dasatinib and quercetin markedly reduced these senescent cells and TRAP⁺ cells, eventually alleviating root resorption. Altogether, these results unveil those aberrant stimuli in orthodontic intrusive tooth movement induced RANKL⁺ early senescent cells, which have a pivotal role in odontoclastogenesis and subsequent root resorption. These findings offer a new therapeutic target to prevent root resorption during orthodontic tooth movement.

Effect and mechanism of Tangzhiqing in improving cardiac function in mice with hyperlipidaemia complicated with myocardial ischaemia

Purpose

Tangzhiqing formula (TZQ) is a traditional Chinese medicine prescribed to treat lipid metabolism disorders, atherosclerosis, diabetes and diabetic cardiomyopathy. However, some challenges and hurdles remain. TZQ showed promising results in treating diabetes and hyperlipidaemia. However, its effect on and mechanism of action in hyperlipidaemia complicated with myocardial ischaemia (HL-MI) remain unknown.

Methods

In this study, a network pharmacology-based strategy integrating target prediction was adopted to predict the targets of TZQ relevant to the treatment of HL-MI and to further explore the involved pharmacological mechanisms.

Results

A total of 104 potential therapeutic targets were obtained, including MMP9, Bcl-2, and Bax, which may be related to the apoptosis and PI3K/AKT signalling pathways. Then, we confirmed these potential targets and pathways with animal experimentation. TZQ reduced lipid levels, increased the expression levels of Bcl-2, decreased Bax, caspase-3 and caspase-9 expression levels, and activated the PI3K/AKT signalling pathway.

Conclusion

In conclusion, this study provides new insights into the protective mechanisms of TZQ against HL-MI through network pharmacology and pharmacological approaches.

Roles of TSP1-CD47 signaling pathway in senescence of endothelial cells: cell cycle, inflammation and metabolism

Endothelial cells (ECs) serve as a barrier with forming a monolayer lining in the surface of vascular system. Many mature cell types are post-mitotic like neurons, but ECs have the ability to grow during angiogenesis. Vascular endothelial growth factor (VEGF) stimulates growth of vascular ECs derived from arteries, veins, and lymphatics and induces angiogenesis. Senescence of ECs is regarded as a key contributor in aging-induced vascular dysfunction via evoking increase of ECs permeability, impairment of angiogenesis and vascular repair. Several genomics and proteomics studies on ECs senescence reported changes in gene and protein expression that directly correlate with vascular systemic disorder. CD47 functions as a signaling receptor for secreted matricellular protein thrombospondin-1 (TSP1) and plays an important role in several fundamental cellular functions, including proliferation, apoptosis, inflammation, and atherosclerotic response. TSP1-CD47 signaling is upregulated with age in ECs, concurrent with suppression of key self-renewal genes. Recent studies indicate that CD47 is involved in regulation of senescence, self-renewal and inflammation. In this review, we highlight the functions of CD47 in senescent ECs, including modulation of cell cycle, mediation of inflammation and metabolism by the experimental studies, which may provide CD47 as a potential therapeutic target for aging-associated vascular dysfunction.

Artificial Intelligence-Derived Electrocardiogram Assessment of Cardiac Age and Molecular Markers of Senescence in Heart Failure

OBJECTIVE

To ascertain whether heart failure (HF) itself is a senescent phenomenon independent of age, and how this is reflected at a molecular level in the circulating progenitor cell niche, and at a substrate level using a novel electrocardiogram (ECG)-based artificial intelligence platform.

PATIENTS AND METHODS

Between October 14, 2016, and October 29, 2020, CD34⁺ progenitor cells were analyzed by flow cytometry and isolated by magnetic-activated cell sorting from patients of similar age with New York Heart Association functional classes IV (n = 17) and I-II (n = 10) heart failure with reduced ejection fraction and healthy controls (n = 10). CD34⁺ cellular senescence was quantitated by human telomerase reverse transcriptase expression and telomerase expression by quantitative polymerase chain reaction, and senescence-associated secretory phenotype (SASP) protein expression assayed in plasma. An ECG-based artificial intelligence (AI) algorithm was used to determine cardiac age and difference from chronological age (AI ECG age gap).

RESULTS

CD34⁺ counts and telomerase expression were significantly reduced and AI ECG age gap and SASP expression increased in all HF groups compared with healthy controls. Expression of SASP protein was closely associated with telomerase activity and severity of HF phenotype and inflammation. Telomerase activity was more closely associated with CD34⁺ cell counts and AI ECG age gap.

CONCLUSION

We conclude from this pilot study that HF may promote a senescent phenotype independent of chronological age. We show for the first time that the AI ECG in HF shows a phenotype of cardiac aging beyond chronological age, and appears to be associated with cellular and molecular evidence of senescence.

Direct administration of mesenchymal stem cell-derived mitochondria improves cardiac function after infarction via ameliorating endothelial senescence

Mitochondrial dysfunction is considered to be a key contributor to the development of heart failure. Replacing injured mitochondria with healthy mitochondria to restore mitochondrial bioenergy in myocardium holds great promise for cardioprotection after infarction. This study aimed to investigate whether direct transplantation of exogenous mitochondria derived from mesenchymal stem cells (MSC-mt) is beneficial and superior in protecting cardiac function in a mouse model of myocardial infarction (MI) compared to mitochondria derived from skin fibroblast (FB-mt) and to explore the underlying mechanisms from their effects on the endothelial cells. The isolated MSC-mt presented intact mitochondrial morphology and activity, as determined by electron microscopy, JC-1 mitochondrial membrane potential assay, and seahorse assay. Direct injection of MSC-mt into the peri-infarct region in a mouse MI model enhanced blood vessel density, inhibited cardiac remodeling and apoptosis, thus improving heart function compared with FB-mt group. The injected MSC-mt can be tracked in the endothelial cells. In vitro, the fluorescence signal of MSC-mt can be detected in human umbilical vein endothelial cells (HUVECs) by confocal microscopy and flow cytometry after coculture. Compared to FB-mt, MSC-mt more effectively protected the HUVECs from oxidative stress-induced apoptosis and reduced mitochondrial production of reactive oxygen species. MSC-mt presented superior capacity in inducing tube formation, enhancing SCF secretion, ATP content and cell proliferation in HUVECs compared to FB-mt. Mechanistically, MSC-mt administration alleviated oxidative stress-induced endothelial senescence via activation of ERK pathway. These findings suggest that using MSCs as sources of mitochondria is feasible and that proangiogenesis could be the mechanism by which MSC-mt transplantation attenuates MI. MSC-mt transplantation might serve as a new therapeutic strategy for treating MI.

Pharmacological clearance of senescent cells improves cardiac remodeling and function after myocardial infarction in female aged mice

Cardiovascular diseases (CVD) are predominantly an aging disease. Important sex-specific differences exist and the mechanism(s) by which this sex-by-age interaction influences CVD development and progression remains elusive. Accordingly, it is still unknown whether cell senescence, a main feature of cardiac male aging, is a significant feature also of the female aged mouse heart and whether senolytics, senescence-clearing compounds, promote myocardial repair and regeneration after myocardial infarction (MI) in aged female mice. To this aim, the combination of two senolytics, dasatinib and quercetin (D+Q) or just their vehicle was administered to 22-24 months old C57BL/6 female mice after MI. D+Q improved global left ventricle function and myocardial performance after MI whereby female cardiac aging is characterized by accumulation of cardiac senescent cells that are further increased by MI. Despite their terminal differentiation nature, also cardiomyocytes acquire a senescent phenotype with age in females. D+Q removed senescent cardiac non-myocyte and myocyte cells ameliorating cardiac remodeling and regeneration. Senolytics removed aged dysfunctional cardiac stem/progenitor cells (CSCs), relieving healthy CSCs with normal proliferative and cardiomyogenic differentiation potential. In conclusions, cardiac senescent cells accumulate in the aged female hearts. Removing senescent cells is a key therapeutic target for efficient repair of the aged female heart.

Ginsenoside Rh2 mitigates doxorubicin-induced cardiotoxicity by inhibiting apoptotic and inflammatory damage and weakening pathological remodelling in breast cancer-bearing mice

OBJECTIVES

There are presently a few viable ways to reduce cardiotoxicity of doxorubicin (Dox). The combination of chemotherapy agents with natural compounds delivers greater efficacy and reduces adverse effects in recent researches for cancer treatment. Here, we examined the potential effect of ginsenoside Rh2 on a Dox-based regimen in chemotherapy treatment.

MATERIALS AND METHODS

Human breast tumour (MDA-MB-231) xenograft nude mice, human cardiac ventricle fibroblasts, and human umbilical vein endothelial cells (HUVEC) were employed in the present study. Histology, immunohistochemistry, immunofluorescence, western blot, antibody array, and RNA-sequencing analyses were utilized to assess the protective effect of Rh2 on cardiotoxicity induced by Dox and the underlying mechanisms.

RESULTS

Rh2-reduced cardiotoxicity by inhibiting the cardiac histopathological changes, apoptosis and necrosis, and consequent inflammation. Pathological remodelling was attenuated by reducing fibroblast to myofibroblast transition (FMT) and endothelial-mesenchymal transition (EndMT) in hearts. RNA-sequencing analysis showed that Dox treatment predominantly targets cell cycle and attachment of microtubules and boosted tumour necrosis, chemokine and interferon-gamma production, response to cytokine and chemokine, and T cell activation, whereas Rh2 regulated these effects. Intriguingly, Rh2 also attenuated fibrosis via promoting senescence in myofibroblasts and reversing established myofibroblast differentiation in EndMT.

CONCLUSIONS

Rh2 regulates multiple pathways in the Dox-provoked heart, proposing a potential candidate for cancer supplement and therapy-associated cardiotoxicity.

Network pharmacology analysis and experimental validation to explore the mechanism of Shenlian extract on myocardial ischemia

ETHNOPHARMACOLOGICAL RELEVANCE

Shenlian extract (SL), extracted from Salvia miltiorrhiza Bunge and Andrographis paniculata (Burm. f.) Nees, has been proved to be effective in the prevention and treatment of atherosclerosis. Recently, we have partially elucidated the mechanisms involved in the therapeutic effects of SL on myocardial ischemia (MI). However, the underlying mechanisms remain largely unclear.

AIM OF THE STUDY

This study aims to explore the potential molecular mechanism of SL on MI on the basis of network pharmacology.

MATERIALS AND METHODS

First, the main active ingredients of SL were screened in the Traditional Chinese Medicine Integrated Database, and the MI-associated targets were collected from the DisGeNET database. Then, we used compound-target and target-pathway networks to uncover the therapeutic mechanisms of SL. On the basis of network pharmacology analysis results, we assessed the effects of SL in MI rat model and oxygen glucose deprivation model of H9c2 cells and validated the possible molecular mechanisms of SL on myocardial injury in vivo and in vitro.

RESULTS

The network pharmacology results showed that 37 potential targets were recognized, including TNF-α, Bcl-2, STAT3, PI3K and MMP2. These results revealed that the possible targets of SL were involved in the regulation of inflammation and apoptosis signaling pathway. Then, in vivo experiments indicated that SL significantly reduced the myocardial infarction size of MI rats. Serum CK-MB, cTnT, CK, LDH, and AST levels were significantly decreased by SL (P < 0.05 or P < 0.01). In vitro, SL significantly increased H9c2 cell viability. The levels of inflammation factors including TNF-α and MMP2 were significantly decreased by SL (P < 0.05 or P < 0.01). TUNEL and Annexin V/propidium iodide assays indicated that SL could significantly decrease the cell apoptotic rate in vivo and in vitro (P < 0.05 or P < 0.01). The remarkable upregulation of anti-apoptotic Bcl-2 and downregulation of pro-apoptotic Bax protein level further confirmed this result. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the PI3K-AKT and JAK2-STAT3 pathways were significantly enriched in SL. Compared with the model group, SL treatment significantly activated the PI3K-AKT and JAK2-STAT3 pathways in vivo and in vitro according to Western blot analyses.

CONCLUSION

SL could protect the myocardium from MI injury. The underlying mechanism may be related to the reduction of inflammation and apoptosis by activating the PI3K/AKT and JAK2/STAT3 pathways.

Telomeres and Mitochondrial Metabolism: Implications for Cellular Senescence and Age-related Diseases

Cellular senescence is an irreversible cell arrest process, which is determined by a variety of complicated mechanisms, including telomere attrition, mitochondrial dysfunction, metabolic disorders, loss of protein homeostasis, epigenetic changes, etc. Cellular senescence is causally related to the occurrence and development of age-related disease. The elderly is liable to suffer from disorders such as neurodegenerative diseases, cancer, and diabetes. Therefore, it is increasingly imperative to explore specific countermeasures for the treatment of age-related diseases. Numerous studies on humans and mice emphasize the significance of metabolic imbalance caused by short telomeres and mitochondrial damages in the onset of age-related diseases. Although the experimental data are relatively independent, more and more evidences have shown that there is mutual crosstalk between telomeres and mitochondrial metabolism in the process of cellular senescence. This review systematically discusses the relationship between telomere length, mitochondrial metabolic disorder, as well as their underlying mechanisms for cellular senescence and age-related diseases. Future studies on telomere and mitochondrial metabolism may shed light on potential therapeutic strategies for age-related diseases. Graphical Abstract The characteristics of cellular senescence mainly include mitochondrial dysfunction and telomere attrition. Mitochondrial dysfunction will cause mitochondrial metabolic disorders, including decreased ATP production, increased ROS production, as well as enhanced cellular apoptosis. While oxidative stress reaction to produce ROS, leads to DNA damage, and eventually influences telomere length. Under the stimulation of oxidative stress, telomerase catalytic subunit TERT mainly plays an inhibitory role on oxidative stress, reduces the production of ROS and protects telomere function. Concurrently, mitochondrial dysfunction and telomere attrition eventually induce a range of age-related diseases, such as T2DM, osteoporosis, AD, etc. :increase; :reduce;⟝:inhibition.

Transcriptome sequencing and lncRNA-miRNA-mRNA network construction in cardiac fibrosis and heart failure

Cardiac fibrosis (CF) and heart failure (HF) are common heart diseases, and severe CF can lead to HF. In this study, we tried to find their common potential molecular markers, which may help the diagnosis and treatment of CF and HF. RNA library construction and high-throughput sequencing were performed. The DESeq2 package in R was used to screen differentially expressed mRNAs (DEmRNAs), differentially expressed lncRNA (DElncRNAs) and differentially expressed miRNA (DEmiRNAs) between different samples. The common DEmRNAs, DElncRNAs and DEmiRNAs for the two diseases were obtained. The ConsensusPathDB (CPDB) was used to perform biological function enrichment for common DEmRNAs. Gene interaction network was constructed to screen out key genes. Subsequently, real-time polymerase chain reaction (RT-PCR) verification was performed. Lastly, GSE104150 and GSE21125 data sets were utilized for expression validation and diagnostic analysis. There were 1477 DEmRNAs, 502 DElncRNAs and 36 DEmiRNAs between CF and healthy control group. There were 607 DEmRNAs, 379DElncRNAs,s and 42 DEmiRNAs between HF and healthy control group. CH and FH shared 146 DEmRNAs, 80 DElncRNAs, and 6 DEmiRNAs. Hsa-miR-144-3p, CCNE2, C9orf72, MAP3K20-AS1, LEF1-AS1, AC243772.2, FLJ46284, and AC239798.2 were key molecules in lncRNA-miRNA-mRNA network. In addition, hsa-miR-144-3p and CCNE2 may be considered as potential diagnostic gene biomarkers in HF. In this study, the identification of common biomarkers of CF and HF may help prevent CF to HF transition as early as possible.

Identification of enhancer regulatory elements that direct epicardial gene expression during zebrafish heart regeneration

The epicardium is a mesothelial tissue layer that envelops the heart. Cardiac injury activates dynamic gene expression programs in epicardial tissue, which in zebrafish enables subsequent regeneration through paracrine and vascularizing effects. To identify tissue regeneration enhancer elements (TREEs) that control injury-induced epicardial gene expression during heart regeneration, we profiled transcriptomes and chromatin accessibility in epicardial cells purified from regenerating zebrafish hearts. We identified hundreds of candidate TREEs, which are defined by increased chromatin accessibility of non-coding elements near genes with increased expression during regeneration. Several of these candidate TREEs were incorporated into stable transgenic lines, with five out of six elements directing injury-induced epicardial expression but not ontogenetic epicardial expression in larval hearts. Whereas two independent TREEs linked to the gene gnai3 showed similar functional features of gene regulation in transgenic lines, two independent ncam1a-linked TREEs directed distinct spatiotemporal domains of epicardial gene expression. Thus, multiple TREEs linked to a regeneration gene can possess either matching or complementary regulatory controls. Our study provides a new resource and principles for understanding the regulation of epicardial genetic programs during heart regeneration. This article has an associated 'The people behind the papers' interview.

Cellular Senescence in Cardiovascular Diseases: A Systematic Review

Aging is a prominent risk factor for cardiovascular diseases, which is the leading cause of death around the world. Recently, cellular senescence has received potential attention as a promising target in preventing cardiovascular diseases, including acute myocardial infarction, atherosclerosis, cardiac aging, pressure overload-induced hypertrophy, heart regeneration, hypertension, and abdominal aortic aneurysm. Here, we discuss the mechanisms underlying cellular senescence and describe the involvement of senescent cardiovascular cells (including cardiomyocytes, endothelial cells, vascular smooth muscle cells, fibroblasts/myofibroblasts and T cells) in age-related cardiovascular diseases. Then, we highlight the targets (SIRT1 and mTOR) that regulating cellular senescence in cardiovascular disorders. Furthermore, we review the evidence that senescent cells can exert both beneficial and detrimental implications in cardiovascular diseases on a context-dependent manner. Finally, we summarize the emerging pro-senescent or anti-senescent interventions and discuss their therapeutic potential in preventing cardiovascular diseases.