Somatic Mutations in Cardiovascular Disease

Beyond the Heartbeat: Single-Cell Omics Redefining Cardiovascular Research

PURPOSE OF REVIEW

This review aims to explore recent advances in single-cell omics techniques as applied to various regions of the human heart, illuminating cellular diversity, regulatory networks, and disease mechanisms. We examine the contributions of single-cell transcriptomics, genomics, proteomics, epigenomics, and spatial transcriptomics in unraveling the complexity of cardiac tissues.

RECENT FINDINGS

Recent strides in single-cell omics technologies have revolutionized our understanding of the heart's cellular composition, cell type heterogeneity, and molecular dynamics. These advancements have elucidated pathological conditions as well as the cellular landscape in heart development. We highlight emerging applications of integrated single-cell omics, particularly for cardiac regeneration, disease modeling, and precision medicine, and emphasize the transformative potential of these technologies to advance cardiovascular research and clinical practice.

Impact of clonal haematopoiesis on atherosclerotic cardiovascular disease according to low-density lipoprotein cholesterol levels in general population

AIMS

Clonal haematopoiesis of indeterminate potential (CHIP), defined as a clonal expansion of age-related recurrent somatic mutations, has recently emerged as a novel cardiovascular risk factor. However, the precise role of CHIP in the development of atherosclerotic cardiovascular disease (ASCVD) remains unclear.

METHODS AND RESULTS

Among 4300 asymptomatic Korean participants aged 40-79 years, we investigated the risk of ASCVD by CHIP and the interplay between CHIP and conventional risk factors in ASCVD development. Additionally, we assessed changes in coronary arteries based on the presence of CHIP using coronary computed tomography angiography (CCTA). CHIP was present in 363 participants (8.4%), and its prevalence increased with age. Commonly mutated genes were DNMT3A, TET2, and ASXL1, in order. During the follow-up (median 4.7 years), 18 ASCVD cases (5.0%) were observed in CHIP carriers vs. 62 (1.6%) in non-carriers (P < 0.001), indicating an elevated risk of ASCVD associated with CHIP [adjusted hazard ratio (HR) 2.49; 95% confidence interval (CI) 1.45-4.29; P < 0.001]. Notably, with high levels of LDL cholesterol, CHIP enhanced the risk of ASCVD (adjusted HR 6.20; 95% CI 3.14-12.23; P < 0.001), demonstrating synergism between CHIP and LDL cholesterol levels (S-index 4.94; 95% CI 1.08-22.53; P = 0.039). Serial CCTAs confirmed that CHIP, in conjunction with high LDL cholesterol levels, had a significant early impact on coronary arteries, revealing new measurable coronary atherosclerosis, mainly with unstable plaque, in proximal lesions.

CONCLUSION

The presence of CHIP was significantly associated with the risk of ASCVD, promoting the early stage of atherosclerosis through synergy with high LDL cholesterol in the general population.

Somatic Variants Acquired Later in Life Associated with Thoracic Aortic Aneurysms: JAK2 V617F

The JAK2 V617F somatic variant is a well-known driver of myeloproliferative neoplasms (MPN) associated with an increased risk for athero-thrombotic cardiovascular disease. Recent studies have demonstrated its role in the development of thoracic aortic aneurysm (TAA). However, limited clinical information and level of JAK2 V617F burden have been provided for a comprehensive evaluation of potential confounders. A retrospective genotype-first study was conducted to identify carriers of the JAK2 V617F variant from an internal exome sequencing database in Yale DNA Diagnostics Lab. Additionally, the overall incidence of somatic variants in the JAK2 gene across various tissue types in the healthy population was carried out based on reanalysis of SomaMutDB and data from the UK Biobank (UKBB) cohort to compare our dataset to the population prevalence of the variant. In our database of 12,439 exomes, 594 (4.8%) were found to have a thoracic aortic aneurysm (TAA), and 12 (0.049%) were found to have a JAK2 V617F variant. Among the 12 JAK2 V617F variant carriers, five had a TAA (42%), among whom four had an ascending TAA and one had a descending TAA, with a variant allele fraction ranging from 11.2% to 20%. Among these five patients, 60% were female, and average age at diagnosis was 70 (49-79). The mean ascending aneurysm size was 5.05 cm (range 4.6-5.5 cm), and four patients had undergone surgical aortic replacement or repair. UKBB data revealed a positive correlation between the JAK2 V617F somatic variant and aortic valve disease (effect size 0.0086, p = 0.85) and TAA (effect size = 0.004, p = 0.92), although not statistically significant. An unexpectedly high prevalence of TAA in our dataset (5/594, 0.84%) is greater than the prevalence reported before for the general population, supporting its association with TAA. JAK2 V617F may contribute a meaningful proportion of otherwise unexplained aneurysm patients. Additionally, it may imply a potential JAK2-specific disease mechanism in the developmental of TAA, which suggests a possible target of therapy that warrants further investigation.

Severity of effect considerations regarding the use of mutation as a toxicological endpoint for risk assessment: A report from the 8th International Workshop on Genotoxicity Testing (IWGT)

Exposure levels without appreciable human health risk may be determined by dividing a point of departure on a dose-response curve (e.g., benchmark dose) by a composite adjustment factor (AF). An "effect severity" AF (ESAF) is employed in some regulatory contexts. An ESAF of 10 may be incorporated in the derivation of a health-based guidance value (HBGV) when a "severe" toxicological endpoint, such as teratogenicity, irreversible reproductive effects, neurotoxicity, or cancer was observed in the reference study. Although mutation data have been used historically for hazard identification, this endpoint is suitable for quantitative dose-response modeling and risk assessment. As part of the 8th International Workshops on Genotoxicity Testing, a sub-group of the Quantitative Analysis Work Group (WG) explored how the concept of effect severity could be applied to mutation. To approach this question, the WG reviewed the prevailing regulatory guidance on how an ESAF is incorporated into risk assessments, evaluated current knowledge of associations between germline or somatic mutation and severe disease risk, and mined available data on the fraction of human germline mutations expected to cause severe disease. Based on this review and given that mutations are irreversible and some cause severe human disease, in regulatory settings where an ESAF is used, a majority of the WG recommends applying an ESAF value between 2 and 10 when deriving a HBGV from mutation data. This recommendation may need to be revisited in the future if direct measurement of disease-causing mutations by error-corrected next generation sequencing clarifies selection of ESAF values.

Pathology-based brain arterial disease phenotypes and their radiographic correlates

INTRODUCTION

Brain arterial diseases, including atherosclerosis, vasculitis, and dissections, are major contributors to cerebrovascular morbidity and mortality worldwide. These diseases not only increase the risk of stroke but also play a significant role in neurodegeneration and dementia. Clear and unambiguous terminology and classification of brain arterial disease phenotypes is crucial for research and clinical practice.

MATERIAL AND METHODS

This review aims to summarize and harmonize the terminology used for brain large and small arterial phenotypes based on pathology studies and relate them to imaging phenotypes used in medical research and clinical practice.

CONCLUSIONS AND RESULTS

Arteriosclerosis refers to hardening of the arteries but does not specify the underlying etiology. Specific terms such as atherosclerosis, calcification, or non-atherosclerotic fibroplasia are preferred. Atherosclerosis is defined pathologically by an atheroma. Other brain arterial pathologies occur and should be distinguished from atherosclerosis given therapeutic implications. On brain imaging, intracranial arterial luminal stenosis is usually attributed to atherosclerosis in the presence of atherosclerotic risk factors but advanced high-resolution arterial wall imaging has the potential to more accurately identify the underlying pathology. Regarding small vessel disease, arteriosclerosis is ambiguous and arteriolosclerosis is often used to denote the involvement of arterioles rather than arteries. Lipohyalinosis is sometimes used synonymously with arteriolosclerosis, but less accurately describes this common small vessel thickening which uncommonly shows lipid. Specific measures of small vessel wall thickness, the relationship to the lumen as well as changes in the layer composition might convey objective, measurable data regarding the status of brain small vessels.

Associations between mosaic loss of sex chromosomes and incident hospitalization for atrial fibrillation in the United Kingdom

Background

Mosaic loss of chromosome Y (mLOY) in leukocytes of men reflects genomic instability from aging, smoking, and environmental exposures. A similar mosaic loss of chromosome X (mLOX) occurs among women. However, the associations between mLOY, mLOX, and risk of incident heart diseases are unclear.

Methods

We estimated associations between mLOY, mLOX, and risk of incident heart diseases requiring hospitalization, including atrial fibrillation, myocardial infarction, ischemic heart disease, cardiomyopathy, and heart failure. We analyzed 190,613 men and 224,853 women with genotyping data from the UK Biobank. Among these participants, we analyzed 37,037 men with mLOY and 13,978 women with mLOX detected using Mosaic Chromosomal Alterations caller. Multivariable Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of each incident heart disease in relation to mLOY in men and mLOX in women. Additionally, Mendelian randomization (MR) was conducted to estimate causal associations.

Results

Among men, detectable mLOY was associated with elevated risk of atrial fibrillation (HR=1.06, 95%CI:1.03-1.11). The associations were apparent in both never-smokers (HR=1.07, 95%:1.01-1.14) and ever-smokers (HR=1.05, 95%CI:1.01-1.11) as well as men > and ≤60 years of age. MR analyses supported causal associations between mLOY and atrial fibrillation (HRMR-PRESSO=1.15, 95%CI:1.13-1.18). Among post-menopausal women, we found a suggestive inverse association between detectable mLOX and atrial fibrillation risk (HR=0.90, 95%CI:0.83-0.98). However, associations with mLOY and mLOX were not found for other heart diseases.

Conclusions

Our findings suggest that mLOY and mLOX reflect sex-specific biological processes or exposure profiles related to incident atrial fibrillation requiring hospitalization.

Role of transcriptional cofactors in cardiovascular diseases

Cardiovascular disease is a main cause of mortality in the world and the highest incidence of all diseases. However, the mechanism of the pathogenesis of cardiovascular disease is still unclear, and we need to continue to explore its mechanism of action. The occurrence and development of cardiovascular disease is significantly associated with genetic abnormalities, and gene expression is affected by transcriptional regulation. In this complex process, the protein-protein interaction promotes the RNA polymerase II to the initiation site. And in this process of transcriptional regulation, transcriptional cofactors are responsible for passing cues from enhancers to promoters and promoting the binding of RNA polymerases to promoters, so transcription cofactors playing a key role in gene expression regulation. There is growing evidence that transcriptional cofactors play a critical role in cardiovascular disease. Transcriptional cofactors can promote or inhibit transcription by affecting the function of transcription factors. It can affect the initiation and elongation process of transcription by forming complexes with transcription factors, which are important for the stabilization of DNA rings. It can also act as a protein that interacts with other proteins to affect the expression of other genes. Therefore, the aim of this overview is to summarize the effect of some transcriptional cofactors such as BRD4, EP300, MED1, EZH2, YAP, SIRT6 in cardiovascular disease and to provide a promising therapeutic strategy for the treatment of cardiovascular disease.

Somatic and Germline Variants and Coronary Heart Disease in a Chinese Population

Importance

The genetic basis of coronary heart disease (CHD) has expanded from a germline to somatic genome, including clonal hematopoiesis of indeterminate potential (CHIP). How CHIP confers CHD risk in East Asian individuals, especially those with small clones (variant allele fraction [VAF] 0.5%-2%) and different genetic backgrounds, was completely unknown.

Objective

To investigate the CHIP profile in a general Chinese cohort by deep sequencing and further explore the association between CHIP and incident CHD considering germline predisposition.

Design, Setting, and Participants

This cohort study used data from 3 prospective cohorts in the project Prediction for Atherosclerotic Cardiovascular Disease Risk in China. Participants without cardiovascular disease or cancer at baseline were enrolled in 2001 and 2008 and had a median follow-up of 12.17 years extending into 2021.

Exposures

CHIP mutations were detected by targeted sequencing (mean depth, 916×). A predefined CHD polygenic risk score (PRS) comprising 531 variants was used to evaluate germline predisposition.

Main Outcomes and Measures

The main outcome was first incident CHD.

Results

Among 6181 participants, the median (IQR) age was 53.83 years (45.35-62.39 years); 3082 participants (49.9%) were female, and 3099 (50.1%) were male. A total of 1100 individuals (17.80%) harbored 1372 CHIP mutations at baseline. CHIP was independently associated with incident CHD (hazard ratio [HR], 1.42; 95% CI, 1.18-1.72; P = 2.82 × 10-4) and presented a risk gradient with increasing VAF (P = 3.98 × 10-3 for trend). Notably, individuals with small clones, nearly half of CHIP carriers, also demonstrated a higher CHD risk compared with non-CHIP carriers (HR, 1.33; 95% CI, 1.02-1.74; P = .03) and were 4 years younger than those with VAF of 2% or greater (median age, 58.52 vs 62.70 years). Heightened CHD risk was not observed among CHIP carriers with low PRS (HR, 1.02; 95% CI, 0.64-1.64; P = .92), while high PRS and CHIP jointly contributed a 2.23-fold increase in risk (95% CI, 1.51-3.29; P = 6.29 × 10-5) compared with non-CHIP carriers with low PRS. Interestingly, the diversity in CHIP-related CHD risk within each PRS group was substantially diminished when removing variants in the inflammatory pathway from the PRS.

Conclusions

This study revealed that elevated CHD risk attributed to CHIP was nonnegligible even for small clones. Inflammation genes involved in CHD could aggravate or abrogate CHIP-related CHD risk.

Immune response following transcatheter aortic valve procedure

Aortic valve stenosis is the most common type of heart valve disease in the United States and Europe and calcific aortic stenosis (AS) affects 2-7% of people aged 65 years and older. Aortic valve replacement (AVR) is the only effective treatment for individuals with this condition. Transcatheter Aortic Valve Replacement (TAVR) has been widely accepted as a minimally invasive therapeutic approach for addressing symptomatic AS in patients who are considered to have a high risk for traditional surgical intervention. TAVR procedure may have a paradoxical effect on the immune system and inflammatory status. A major portion of these immune responses is regulated by activating or inhibiting inflammatory monocytes and the complement system with subsequent changes in inflammatory cytokines. TAVR has the potential to induce various concurrent exposures, including disruption of the native valve, hemodynamic changes, antigenicity of the bioprosthesis, and vascular damage, which finally lead to the development of inflammation. On the other hand, it is important to acknowledge that TAVR may also have anti-inflammatory effects by helping in the resolution of stenosis.The inflammation and immune response following TAVR are complex processes that significantly impact procedural outcomes and patient well-being. Understanding the underlying mechanisms, identifying biomarkers of inflammation, and exploring therapeutic interventions to modulate these responses are crucial for optimizing TAVR outcomes. Further research is warranted to elucidate the precise immunological dynamics and develop tailored strategies to attenuate inflammation and enhance post-TAVR healing while minimizing complications.

Atrial fibrillation: pathophysiology, genetic and epigenetic mechanisms

Atrial fibrillation (AF) is the most common supraventricular arrhythmia affecting up to 1% of the general population. Its prevalence dramatically increases with age and could reach up to ∼10% in the elderly. The management of AF is a complex issue that is object of extensive ongoing basic and clinical research, it depends on its genetic and epigenetic causes, and it varies considerably geographically and also according to the ethnicity. Mechanistically, over the last decade, Genome Wide Association Studies have uncovered over 100 genetic loci associated with AF, and have shown that European ancestry is associated with elevated risk of AF. These AF-associated loci revolve around different types of disturbances, including inflammation, electrical abnormalities, and structural remodeling. Moreover, the discovery of epigenetic regulatory mechanisms, involving non-coding RNAs, DNA methylation and histone modification, has allowed unravelling what modifications reshape the processes leading to arrhythmias. Our review provides a current state of the field regarding the identification and functional characterization of AF-related genetic and epigenetic regulatory networks, including ethnic differences. We discuss clear and emerging connections between genetic regulation and pathophysiological mechanisms of AF.

DNMT3A clonal hematopoiesis-driver mutations induce cardiac fibrosis by paracrine activation of fibroblasts

Hematopoietic mutations in epigenetic regulators like DNA methyltransferase 3 alpha (DNMT3A), play a pivotal role in driving clonal hematopoiesis of indeterminate potential (CHIP), and are associated with unfavorable outcomes in patients suffering from heart failure (HF). However, the precise interactions between CHIP-mutated cells and other cardiac cell types remain unknown. Here, we identify fibroblasts as potential partners in interactions with CHIP-mutated monocytes. We used combined transcriptomic data derived from peripheral blood mononuclear cells of HF patients, both with and without CHIP, and cardiac tissue. We demonstrate that inactivation of DNMT3A in macrophages intensifies interactions with cardiac fibroblasts and increases cardiac fibrosis. DNMT3A inactivation amplifies the release of heparin-binding epidermal growth factor-like growth factor, thereby facilitating activation of cardiac fibroblasts. These findings identify a potential pathway of DNMT3A CHIP-driver mutations to the initiation and progression of HF and may also provide a compelling basis for the development of innovative anti-fibrotic strategies.

Scrutiny of genome-wide somatic mutation profiles in centenarians identifies the key genomic regions for human longevity

Somatic mutations accumulate with age and are associated closely with human health, their characterization in longevity cohorts remains largely unknown. Here, by analyzing whole genome somatic mutation profiles in 73 centenarians and 51 younger controls in China, we found that centenarian genomes are characterized by a markedly skewed distribution of somatic mutations, with many genomic regions being specifically conserved but displaying a high function potential. This, together with the observed more efficient DNA repair ability in the long-lived individuals, supports the existence of key genomic regions for human survival during aging, with their integrity being of essential to human longevity.

Clonal hematopoiesis of indeterminate potential: implications for the cardiologists

Myeloproliferative neoplasms, including polycythemia vera, essential thrombocythemia, and myelofibrosis, are characterized by somatic gene mutations in bone marrow stem cells, which trigger an inflammatory response influencing the development of associated cardiovascular complications. In recent years, the same mutations were found in individuals with cardiovascular diseases even in the absence of hematological alterations. These genetic events allow the identification of a new entity called 'clonal hematopoiesis of indeterminate potential' (CHIP), as it was uncertain whether it could evolve toward hematological malignancies. CHIP is age-related and, remarkably, myocardial infarction, stroke, and heart failure were frequently reported in these individuals and attributed to systemic chronic inflammation driven by the genetic mutation. We reviewed the connection between clonal hematopoiesis, inflammation, and cardiovascular diseases, with a practical approach to improve clinical practice and highlight the current unmet needs in this area of knowledge.

Molecular and clinical aspects relevant for counseling individuals with clonal hematopoiesis of indeterminate potential

Clonal hematopoiesis of indeterminate potential (CHIP) has fascinated the medical community for some time. Discovered about a decade ago, this phenomenon links age-related alterations in hematopoiesis not only to the later development of hematological malignancies but also to an increased risk of early-onset cardiovascular disease and some other disorders. CHIP is detected in the blood and is characterized by clonally expanded somatic mutations in cancer-associated genes, predisposing to the development of hematologic neoplasms such as MDS and AML. CHIP-associated mutations often involve DNA damage repair genes and are frequently observed following prior cytotoxic cancer therapy. Genetic predisposition seems to be a contributing factor. It came as a surprise that CHIP significantly elevates the risk of myocardial infarction and stroke, and also contributes to heart failure and pulmonary hypertension. Meanwhile, evidence of mutant clonal macrophages in vessel walls and organ parenchyma helps to explain the pathophysiology. Besides aging, there are some risk factors promoting the appearance of CHIP, such as smoking, chronic inflammation, chronic sleep deprivation, and high birth weight. This article describes fundamental aspects of CHIP and explains its association with hematologic malignancies, cardiovascular disorders, and other medical conditions, while also exploring potential progress in the clinical management of affected individuals. While it is important to diagnose conditions that can lead to adverse, but potentially preventable, effects, it is equally important not to stress patients by confronting them with disconcerting findings that cannot be remedied. Individuals with diagnosed or suspected CHIP should receive counseling in a specialized outpatient clinic, where professionals from relevant medical specialties may help them to avoid the development of CHIP-related health problems. Unfortunately, useful treatments and clinical guidelines for managing CHIP are still largely lacking. However, there are some promising approaches regarding the management of cardiovascular disease risk. In the future, strategies aimed at restoration of gene function or inhibition of inflammatory mediators may become an option.

Multiomics tools for improved atherosclerotic cardiovascular disease management

Multiomics studies offer accurate preventive and therapeutic strategies for atherosclerotic cardiovascular disease (ASCVD) beyond traditional risk factors. By using artificial intelligence (AI) and machine learning (ML) approaches, it is possible to integrate multiple 'omics and clinical data sets into tools that can be utilized for the development of personalized diagnostic and therapeutic approaches. However, currently multiple challenges in data quality, integration, and privacy still need to be addressed. In this opinion, we emphasize that joined efforts, exemplified by the AtheroNET COST Action, have a pivotal role in overcoming the challenges to advance multiomics approaches in ASCVD research, with the aim to foster more precise and effective patient care.

Negative Impact of TET2 Mutations on Long-Term Survival After Transcatheter Aortic Valve Replacement

Clonal hematopoiesis of indeterminate potential (CHIP) is considered as being a novel age-related risk factor for cardiovascular diseases. By capture-sequencing of a 67-gene panel, we established a large spectrum of CHIP in 258 patients with aortic valve stenosis undergoing transcatheter aortic valve replacement (TAVR) and assessed their association with long-term survival after TAVR. One or several CHIP variants in 35 genes were identified in 68% of the cohort, DNMT3A and TET2 being the 2 most frequently mutated genes. Patients carrying a TET2-CHIP-driver variant with low variant allele frequency (2%-10%) had a significant decrease in overall survival 5 years after TAVR.

Unveiling the Genetic Footprint: Exploring Somatic Mutations in Peripheral Arterial Disease Progression

Peripheral arterial diseases (PADs) are complex cardiovascular conditions influenced by environmental factors and somatic mutations in multiple genes involved in hematopoiesis and inflammation. While traditional risk factors, such as smoking, hypercholesterolemia, and hypertension, have been extensively studied, the role of somatic mutations in PAD progression remains underexplored. The present article intends to provide a comprehensive commentary of the molecular mechanisms, genetic landscape, prognostic significance, and clinical implications of somatic mutations in PADs. The expansion of clonal hematopoiesis of indeterminate potential (CHIP) clones in the circulating blood, named clonal hematopoiesis (CH), leads to the infiltration of these clones into atherosclerotic plaques and the production of inflammatory cytokines, increasing the risk of cardiovascular diseases, including PADs. Furthermore, recent experimental evidence has demonstrated the involvement of somatically mutated TP53 genes with a high variant allele frequency (VAF) in PAD development and prognosis. This review delves into the relationship between CH and PADs, elucidating the prevalence, impact, and underlying mechanisms of this association. This understanding paves the way for novel therapeutic approaches targeting CHIP to promote tissue regeneration and improve outcomes in PAD patients. It emphasizes the need for further research to fully unravel the genetic footprint of the disease and highlights potential clinical implications. The findings presented in this article lay the foundation for personalized medicine approaches and open avenues for the development of targeted therapies based on somatic mutation profiling.

Latent class analysis-derived classification improves the cancer-specific death stratification of molecular subtyping in colorectal cancer

The molecular subtypes of colorectal cancer (CRC) represent a comprehensive dissection of CRC heterogeneity. However, molecular feature-based classification systems have limitations in accurately prognosticating stratification due to the inability to distinguish cancer-specific deaths. This study aims to establish a classification system that bridges clinical characteristics, cause-specific deaths, and molecular features. We adopted latent class analysis (LCA) on 491,107 first primary CRC patients from the Surveillance, Epidemiology, and End Results (SEER) database to reveal hidden profiles of CRC. The LCA-derived classification scheme was further applied to The Cancer Genome Atlas (TCGA) to assess its effectiveness in improving the accurate stratification of molecular-based subtypes of CRC. Four classes were identified based on latent class analysis integrating demographic and clinicopathological information of CRC patients. The LCA-derived Class 1 (LCAC1) and the LCAC2 showed a high risk of dying from non-CRC, while patients in LCAC3 had a risk of dying from CRC 1.41 times that of LCAC1 (95% confidence interval [CI] = 1.39-1.43). LCAC4 had the lowest probability to die from non-CRC (hazard ratio [HR] = 0.22, 95% CI = 0.21-0.24) compared with LCAC1. Since the LCA-derived classification can identify patients susceptible to CRC-specific death, adjusting for this classification allows molecular-based subtypes to achieve more accurate survival stratification. We provided a classification system capable of distinguish CRC-specific death, which will improve the accuracy of consensus molecular subtypes for CRC patients' survival stratification. Further studies are warranted to confirm the molecular features of LCA-derived classification to inform potential therapeutic strategies and treatment recommendations.

Non-coding RNA-mediated modulation of ferroptosis in cardiovascular diseases

Cardiovascular disease (CVD) is a major contributor to increasing morbidity and mortality worldwide and seriously threatens human health and life. Cardiomyocyte death is considered the pathological basis of various CVDs, including myocardial infarction, heart failure, and aortic dissection. Multiple mechanisms, such as ferroptosis, necrosis, and apoptosis, contribute to cardiomyocyte death. Among them, ferroptosis is an iron-dependent form of programmed cell death that plays a vital role in various physiological and pathological processes, from development and aging to immunity and CVD. The dysregulation of ferroptosis has been shown to be closely associated with CVD progression, yet its underlying mechanisms are still not fully understood. In recent years, a growing amount of evidence suggests that non-coding RNAs (ncRNAs), particularly microRNAs, long non-coding RNAs, and circular RNAs, are involved in the regulation of ferroptosis, thus affecting CVD progression. Some ncRNAs also exhibit potential value as biomarker and/or therapeutic target for patients with CVD. In this review, we systematically summarize recent findings on the underlying mechanisms of ncRNAs involved in ferroptosis regulation and their role in CVD progression. We also focus on their clinical applications as diagnostic and prognostic biomarkers as well as therapeutic targets in CVD treatment. DATA AVAILABILITY: No new data were created or analyzed in this study. Data sharing is not applicable to this article.

High-quality nuclei isolation from postmortem human heart muscle tissues for single-cell studies

Single-cell approaches have become an increasingly popular way of understanding the genetic factors behind disease. Isolation of DNA and RNA from human tissues is necessary to analyze multi-omic data sets, providing information on the single-cell genome, transcriptome, and epigenome. Here, we isolated high-quality single-nuclei from postmortem human heart tissues for DNA and RNA analysis. Postmortem human tissues were obtained from 106 individuals, 33 with a history of myocardial disease, diabetes, or smoking, and 73 controls without heart disease. We demonstrated that the Qiagen EZ1 instrument and kit consistently isolated genomic DNA of high yield, which can be used for checking DNA quality before conducting single-cell experiments. Here, we provide a method for single-nuclei isolation from cardiac tissue, otherwise known as the SoNIC method, which allows for the isolation of single cardiomyocyte nuclei from postmortem tissue by nuclear ploidy status. We also provide a detailed quality control measure for single-nuclei whole genome amplification and a pre-amplification method for confirming genomic integrity.

Clonal hematopoiesis: the nonhereditary genetics of age-associated cardiovascular disease

PURPOSE OF REVIEW

Somatic mutations, described as noninherited changes in DNA that arise and are passed on to descendant cells, are well known to cause cancers; however, it is increasingly appreciated that the propagation of somatic mutations within a tissue may have a role in causing nonneoplastic disorders and abnormalities in elderly individuals. The nonmalignant clonal expansion of somatic mutations in the hematopoietic system is termed clonal hematopoiesis. This review will briefly discuss how this condition has been linked to various age-related diseases outside the hematopoietic system.

RECENT FINDINGS

Clonal hematopoiesis, resulting from leukemic driver gene mutations or mosaic loss of the Y chromosome in leukocytes, is associated with the development of various forms of cardiovascular disease, including atherosclerosis and heart failure, in a mutation-dependent manner.

SUMMARY

Accumulating evidence shows that clonal hematopoiesis represents a new mechanism for cardiovascular disease and a new risk factor that is as prevalent and consequential as the traditional risk factors that have been studied for decades.

Recent advances in CRISPR-based genome editing technology and its applications in cardiovascular research

The rapid development of genome editing technology has brought major breakthroughs in the fields of life science and medicine. In recent years, the clustered regularly interspaced short palindromic repeats (CRISPR)-based genome editing toolbox has been greatly expanded, not only with emerging CRISPR-associated protein (Cas) nucleases, but also novel applications through combination with diverse effectors. Recently, transposon-associated programmable RNA-guided genome editing systems have been uncovered, adding myriads of potential new tools to the genome editing toolbox. CRISPR-based genome editing technology has also revolutionized cardiovascular research. Here we first summarize the advances involving newly identified Cas orthologs, engineered variants and novel genome editing systems, and then discuss the applications of the CRISPR-Cas systems in precise genome editing, such as base editing and prime editing. We also highlight recent progress in cardiovascular research using CRISPR-based genome editing technologies, including the generation of genetically modified in vitro and animal models of cardiovascular diseases (CVD) as well as the applications in treating different types of CVD. Finally, the current limitations and future prospects of genome editing technologies are discussed.

Clonal heamatopoiesis and associated cardiovascular diseases

Cancer and cardiovascular disease share several risk factors. Clonal heamatopoiesis, a novel risk factor associated with both diseases, has received increasing attention in the fields of cardiology, heamatology and oncology. Clonal heamatopoiesis of indeterminate potential refers to the presence of at least one driver mutation in the heamatopoietic cells of peripheral blood without heamatological malignancy. Clonal heamatopoiesis of indeterminate potential is a common age-related condition that affects up to 60% of individuals aged > 80 years. Importantly, clonal heamatopoiesis of indeterminate potential carriers have a 2- to 4-fold higher risk of developing cardiovascular disease than non-carriers. Therefore, we performed an up-to-date review of clonal heamatopoiesis and its association with various forms of cardiovascular disease, including atherosclerotic disease, heart failure, aortic stenosis and pulmonary hypertension. In addition, we reviewed experimental studies that examined the causality and directionality between clonal heamatopoiesis and cardiovascular disease. Lastly, we discussed future research directions that will aid in the design of personalized therapies and preventive strategies for individuals with clonal heamatopoiesis. This review showed that clonal heamatopoiesis of indeterminate potential is a common condition, especially in older patients, and is associated with an increased risk of cardiovascular disease and worse prognosis. However, further research is needed to determine whether anti-inflammatory therapies or therapies that can reduce or eliminate clone size are effective in preventing cardiovascular disease in patients with clonal heamatopoiesis of indeterminate potential.

High-Quality Nuclei Isolation from Postmortem Human Heart Muscle Tissues for Single-Cell Studies

Single-cell approaches have become an increasingly popular way of understanding the genetic factors behind disease. Isolation of DNA and RNA from human tissues is necessary to analyze multi-omic data sets, providing information on the single-cell genome, transcriptome, and epigenome. Here, we isolated high-quality single-nuclei from postmortem human heart tissues for DNA and RNA analysis. Postmortem human tissues were obtained from 106 individuals, 33 with a history of myocardial disease, diabetes, or smoking, and 73 controls without heart disease. We demonstrated that the Qiagen EZ1 instrument and kit consistently isolated genomic DNA of high yield, which can be used for checking DNA quality before conducting single-cell experiments. Here, we provide a method for single-nuclei isolation from cardiac tissue, otherwise known as the SoNIC method, which allows for the isolation of single cardiomyocyte nuclei from postmortem tissue by nuclear ploidy status. We also provide a detailed quality control measure for single-nuclei whole genome amplification and a pre-amplification method for confirming genomic integrity.

The sirtuin family in health and disease

Sirtuins (SIRTs) are nicotine adenine dinucleotide(+)-dependent histone deacetylases regulating critical signaling pathways in prokaryotes and eukaryotes, and are involved in numerous biological processes. Currently, seven mammalian homologs of yeast Sir2 named SIRT1 to SIRT7 have been identified. Increasing evidence has suggested the vital roles of seven members of the SIRT family in health and disease conditions. Notably, this protein family plays a variety of important roles in cellular biology such as inflammation, metabolism, oxidative stress, and apoptosis, etc., thus, it is considered a potential therapeutic target for different kinds of pathologies including cancer, cardiovascular disease, respiratory disease, and other conditions. Moreover, identification of SIRT modulators and exploring the functions of these different modulators have prompted increased efforts to discover new small molecules, which can modify SIRT activity. Furthermore, several randomized controlled trials have indicated that different interventions might affect the expression of SIRT protein in human samples, and supplementation of SIRT modulators might have diverse impact on physiological function in different participants. In this review, we introduce the history and structure of the SIRT protein family, discuss the molecular mechanisms and biological functions of seven members of the SIRT protein family, elaborate on the regulatory roles of SIRTs in human disease, summarize SIRT inhibitors and activators, and review related clinical studies.

Roles of Epigenetics in Cardiac Fibroblast Activation and Fibrosis

Cardiac fibrosis is a common pathophysiologic process associated with numerous cardiovascular diseases, resulting in cardiac dysfunction. Cardiac fibroblasts (CFs) play an important role in the production of the extracellular matrix and are the essential cell type in a quiescent state in a healthy heart. In response to diverse pathologic stress and environmental stress, resident CFs convert to activated fibroblasts, referred to as myofibroblasts, which produce more extracellular matrix, contributing to cardiac fibrosis. Although multiple molecular mechanisms are implicated in CFs activation and cardiac fibrosis, there is increasing evidence that epigenetic regulation plays a key role in this process. Epigenetics is a rapidly growing field in biology, and provides a modulated link between pathological stimuli and gene expression profiles, ultimately leading to corresponding pathological changes. Epigenetic modifications are mainly composed of three main categories: DNA methylation, histone modifications, and non-coding RNAs. This review focuses on recent advances regarding epigenetic regulation in cardiac fibrosis and highlights the effects of epigenetic modifications on CFs activation. Finally, we provide some perspectives and prospects for the study of epigenetic modifications and cardiac fibrosis.

Circulating Monocyte Subsets and Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR), as an alternative to open heart surgery, has revolutionized the treatment of severe aortic valve stenosis (AVS), the most common valvular disorder in the elderly. AVS is now considered a form of atherosclerosis and, like the latter, partly of inflammatory origin. Patients with high-grade AVS have a highly disturbed blood flow associated with high levels of shear stress. The immediate reopening of the valve during TAVR leads to a sudden restoration of a normal blood flow hemodynamic. Despite its good prognosis for patients, TAVR remains associated with bleeding or thrombotic postprocedural complications, involving mechanisms that are still poorly understood. Many studies report the close link between blood coagulation and inflammation, termed thromboinflammation, including monocytes as a major actor. The TAVR procedure represents a unique opportunity to study the influence of shear stress on human monocytes, key mediators of inflammation and hemostasis processes. The purpose of this study was to conduct a review of the literature to provide a comprehensive overview of the impact of TAVR on monocyte phenotype and subset repartition and the association of these parameters with the clinical outcomes of patients with severe AVS who underwent TAVR.

Increasing Complexity of Molecular Landscapes in Human Hematopoietic Stem and Progenitor Cells during Development and Aging

The past five decades have seen significant progress in our understanding of human hematopoiesis. This has in part been due to the unprecedented development of advanced technologies, which have allowed the identification and characterization of rare subsets of human hematopoietic stem and progenitor cells and their lineage trajectories from embryonic through to adult life. Additionally, surrogate in vitro and in vivo models, although not fully recapitulating human hematopoiesis, have spurred on these scientific advances. These approaches have heightened our knowledge of hematological disorders and diseases and have led to their improved diagnosis and therapies. Here, we review human hematopoiesis at each end of the age spectrum, during embryonic and fetal development and on aging, providing exemplars of recent progress in deciphering the increasingly complex cellular and molecular hematopoietic landscapes in health and disease. This review concludes by highlighting links between chronic inflammation and metabolic and epigenetic changes associated with aging and in the development of clonal hematopoiesis.

Sex Differences in Myocardial and Vascular Aging

It is well known that cardiovascular disease manifests differently in women and men. The underlying causes of these differences during the aging lifespan are less well understood. Sex differences in cardiac and vascular phenotypes are seen in childhood and tend to track along distinct trajectories related to dimorphism in genetic factors as well as response to risk exposures and hormonal changes during the life course. These differences underlie sex-specific variation in cardiovascular events later in life, including myocardial infarction, heart failure, ischemic stroke, and peripheral vascular disease. With respect to cardiac phenotypes, females have intrinsically smaller body size-adjusted cardiac volumes and they tend to experience greater age-related wall thickening and myocardial stiffening with aging. With respect to vascular phenotypes, sexual dimorphism in both physiology and pathophysiology are also seen, including overt differences in blood pressure trajectories. The majority of sex differences in myocardial and vascular alterations that manifest with aging seem to follow relatively consistent trajectories from the very early to the very later stages of life. This review aims to synthesize recent cardiovascular aging-related research to highlight clinically relevant studies in diverse female and male populations that can inform approaches to improving the diagnosis, management, and prognosis of cardiovascular disease risks in the aging population at large.