Single-Cell Transcriptomic Analysis Reveals Myocardial Fibrosis Mechanism of Doxorubicin-Induced Cardiotoxicity.

Myocardial fibrosis is a pathological feature of doxorubicin-induced chronic cardiotoxicity that severely affects the prognosis of oncology patients. However, the specific cellular and molecular mediators driving doxorubicin-induced cardiac fibrosis, and the relative impact of different cell populations on cardiac fibrosis, remain unclear.This study aimed to explore the mechanism of doxorubicin-induced cardiotoxicity and myocardial fibrosis and to find potential therapeutic targets. Single-cell RNA sequencing was used to analyze the transcriptome of non-cardiomyocytes from normal and doxorubicin-induced chronic cardiotoxicity in mouse model heart tissue.We established a mouse model of doxorubicin-induced cardiotoxicity with a well-defined fibrotic phenotype. Analysis of single-cell sequencing results showed that fibroblasts were the major origin of extracellular matrix in doxorubicin-induced myocardial fibrosis. Further resolution of fibroblast subclusters showed that resting fibroblasts were converted to matrifibrocytes and then to myofibroblasts to participate in the myocardial remodeling process in response to doxorubicin treatment. Ctsb expression was significantly upregulated in fibroblasts after doxorubicin-induced.This study provides a comprehensive map of the non-cardiomyocyte landscape at high resolution, reveals multiple cell populations contributing to pathological remodeling of the cardiac extracellular matrix, and identifies major cellular sources of myofibroblasts and dynamic gene-expression changes in fibroblast activation. Finally, we used this strategy to detect potential therapeutic targets and identified Ctsb as a specific target for fibroblasts in doxorubicin-induced myocardial fibrosis.

Isolated Perfused Hearts for Cardiovascular Research: An Old Dog with New Tricks.

In modern cardiovascular research, isolated perfused hearts have become cost-effective and highly reproducible tools to investigate the mechanisms of cardiovascular diseases (CVDs). Since they were first introduced in the nineteenth century, isolated perfused hearts have been extensively used for testing novel therapies, elucidating cardiac metabolic and electrophysiological activities, and modeling CVDs, including ischemic heart disease, arrhythmias, and hyperacute rejection. In recent years, ex vivo heart perfusion (EVHP) has shown potential in cardiac transplantation by allowing prolonged preservation and reconditioning of donor hearts. In this review, we summarize the evolution of the isolated perfused heart technique and its applications in cardiovascular research to help researchers comprehensively understand the capabilities of isolated heart models and provide guidance to use them to investigate various CVDs.

Primate Model Carrying LMNA Mutation Develops Dilated Cardiomyopathy.

To solve the clinical transformation dilemma of lamin A/C (LMNA)-mutated dilated cardiomyopathy (LMD), we developed an LMNA-mutated primate model based on the similarity between the phenotype of primates and humans. We screened out patients with LMD and compared the clinical data of LMD with TTN-mutated and mutation-free dilated cardiomyopathy to obtain the unique phenotype. After establishment of the LMNA c.357-2A>G primate model, primates were continuously observed for 48 months, and echocardiographic, electrophysiological, histologic, and transcriptional data were recorded. The LMD primate model was found to highly simulate the phenotype of clinical LMD. In addition, the LMD primate model shared a similar natural history with humans.

A single-cell atlas of lung homeostasis reveals dynamic changes during development and aging.

Aging is a global challenge, marked in the lungs by function decline and structural disorders, which affects the health of the elderly population. To explore anti-aging strategies, we develop a dynamic atlas covering 45 cell types in human lungs, spanning from embryonic development to aging. We aim to apply the discoveries of lung's development to address aging-related issues. We observe that both epithelial and immune cells undergo a process of acquisition and loss of essential function as they transition from development to aging. During aging, we identify cellular phenotypic alternations that result in reduced pulmonary compliance and compromised immune homeostasis. Furthermore, we find a distinctive expression pattern of the ferritin light chain (FTL) gene, which increases during development but decreases in various types of lung cells during the aging process.

A Heterozygous Phospholamban Variant (p.R14del) Leads to Left Ventricular Involvement and Heart Failure Phenotypes in Arrhythmogenic Right Ventricular Cardiomyopathy.

This study aimed to determine the prevalence and clinical features of Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) caused by pathogenic mutations in the Phospholamban (PLN) gene. The study included 170 patients who had a confirmed diagnosis of ARVC and underwent PLN genetic screening using next-generation sequencing. The findings of this study provide valuable insights into the association between PLN mutations and ARVC, which can aid in the development of more effective diagnostic and treatment strategies for ARVC patients. Out of the patients evaluated, six had a rare pathogenic mutation in PLN with the same p.R14del variant. Family screening revealed that heterozygous carriers of p.R14del exhibited a definite ARVC phenotype. In clinical studies, individuals with the p.R14del mutation experienced a similar rate of malignant arrhythmia events as those with classic desmosome mutations. After adjusting for covariates, individuals with PLN mutations had a two point one seven times greater likelihood of experiencing transplant-related risks compared to those who did not possess PLN mutations (95% CI 1.08-6.82, p = 0.035). The accumulation of left ventricular fat and fibers is a pathological marker for ARVC patients with p.R14del mutations. In a cohort of 170 Chinese ARVC patients, three point five percent of probands had the PLN pathogenic variant (p.R14del) and all were female. Our data shows that PLN-related ARVC patients are at high risk for ventricular arrhythmias and heart failure, which requires clinical differentiation from classic ARVC. Furthermore, carrying the p.R14del mutation can be an independent prognostic risk factor in ARVC patients. Supplementary Information: The online version contains supplementary material available at 10.1007/s43657-023-00126-w.

Single-cell RNA sequencing in donor and end-stage heart failure patients identifies NLRP3 as a therapeutic target for arrhythmogenic right ventricular cardiomyopathy.

BACKGROUND: Dilation may be the first right ventricular change and accelerates the progression of threatening ventricular tachyarrhythmias and heart failure for patients with arrhythmogenic right ventricular cardiomyopathy (ARVC), but the treatment for right ventricular dilation remains limited. METHODS: Single-cell RNA sequencing (scRNA-seq) of blood and biventricular myocardium from 8 study participants was performed, including 6 end-stage heart failure patients with ARVC and 2 normal controls. ScRNA-seq data was then deeply analyzed, including cluster annotation, cellular proportion calculation, and characterization of cellular developmental trajectories and interactions. An integrative analysis of our single-cell data and published genome-wide association study-based data provided insights into the cell-specific contributions to the cardiac arrhythmia phenotype of ARVC. Desmoglein 2 (Dsg2)mut/mut mice were used as the ARVC model to verify the therapeutic effects of pharmacological intervention on identified cellular cluster. RESULTS: Right ventricle of ARVC was enriched of CCL3+ proinflammatory macrophages and TNMD+ fibroblasts. Fibroblasts were preferentially affected in ARVC and perturbations associated with ARVC overlap with those reside in genetic variants associated with cardiac arrhythmia. Proinflammatory macrophages strongly interact with fibroblast. Pharmacological inhibition of Nod-like receptor protein 3 (NLRP3), a transcriptional factor predominantly expressed by the CCL3+ proinflammatory macrophages and several other myeloid subclusters, could significantly alleviate right ventricular dilation and dysfunction in Dsg2mut/mut mice (an ARVC mouse model). CONCLUSIONS: This study provided a comprehensive analysis of the lineage-specific changes in the blood and myocardium from ARVC patients at a single-cell resolution. Pharmacological inhibition of NLRP3 could prevent right ventricular dilation and dysfunction of mice with ARVC.

Profiling cardiomyocytes at single cell resolution reveals COX7B could be a potential target for attenuating heart failure in cardiac hypertrophy.

Cardiac hypertrophy can develop to end-stage heart failure (HF), which inevitably leading to heart transplantation or death. Preserving cardiac function in cardiomyocytes (CMs) is essential for improving prognosis in hypertrophic cardiomyopathy (HCM) patients. Therefore, understanding transcriptomic heterogeneity of CMs in HCM would be indispensable to aid potential therapeutic targets investigation. We isolated primary CM from HCM patients who had extended septal myectomy, and obtained transcriptomes in 338 human primary CM with single-cell tagged reverse transcription (STRT-seq) approach. Our results revealed that CMs could be categorized into three subsets in nonfailing HCM heart: high energy synthesis cluster, high cellular metabolism cluster and intermediate cluster. The expression of electron transport chain (ETC) was up-regulated in larger-sized CMs from high energy synthesis cluster. Of note, we found the expression of Cytochrome c oxidase subunit 7B (COX7B), a subunit of Complex IV in ETC had trends of positively correlation with CMs size. Further, by assessing COX7B expression in HCM patients, we speculated that COX7B was compensatory up-regulated at early-stage but down-regulated in failing HCM heart. To test the hypothesis that COX7B might participate both in hypertrophy and HF progression, we used adeno associated virus 9 (AAV9) to mediate the expression of Cox7b in pressure overload-induced mice. Mice in vivo data supported that knockdown of Cox7b would accelerate HF and Cox7b overexpression could restore partial cardiac function in hypertrophy. Our result highlights targeting COX7B and preserving energy synthesis in hypertrophic CMs could be a promising translational direction for HF therapeutic strategy.

Acceptor engineering-facilitated versatile AIEgen for mitochondria-targeted multimodal imaging-guided cancer photoimmunotherapy.

Photoimmunotherapy has been acknowledged to be an unprecedented strategy to obtain significantly improved cancer treatment efficacy. In this regard, the exploitation of high-performance multimodal phototheranostic agents is highly desired. Apart from tailoring electron donors, acceptor engineering is gradually rising as a deliberate approach in this field. Herein, we rationally designed a family of aggregation-induced emission (AIE)-active compounds with the same donors but different acceptors based on the acceptor engineering. Through finely adjusting the functional groups on electron acceptors, the electron affinity of electron acceptors and the conformation of the compounds were simultaneously modulated. It was found that one of the molecules (named DCTIC), bearing a moderately electrophilic electron acceptor and the best planarity, exhibited optimal phototheranostic properties in terms of light-harvesting ability, fluorescence emission, reactive oxygen species (ROS) production, and photothermal performance. For the purpose of amplified therapeutic outcomes, DCTIC was fabricated into tumor and mitochondria dual-targeted DCTIC nanoparticles (NPs), which afforded good performance in the fluorescence/photoacoustic/photothermal trimodal imaging-guided photodynamic/photothermal-synergized cancer immunotherapy with the combination of programmed cell death protein-1 (PD-1) antibody. Not only the primary tumors were totally eradicated, but efficient growth inhibition of distant tumors was also realized.

Inhibition of NETosis via PAD4 alleviated inflammation in giant cell myocarditis.

Giant cell myocarditis (GCM) is a rare, usually rapidly progressive, and potentially fatal disease. Detailed inflammatory responses remain unknown, in particular the formation of multinucleate giant cells. We performed single-cell RNA sequencing analysis on 15,714 Cd45+ cells extracted from the hearts of GCM rats and normal rats. NETosis has been found to contribute to the GCM process. An inhibitor of NETosis, GSK484, alleviated GCM inflammation in vivo. MPO (a marker of neutrophils) and H3cit (a marker of NETosis) were expressed at higher levels in patients with GCM than in patients with DCM and healthy controls. Imaging mass cytometry analysis revealed that immune cell types within multinucleate giant cells included CD4+ T cells, CD8+ T cells, neutrophils, and macrophages but not B cells. We elucidated the role of NETosis in GCM pathogenesis, which may serve as a potential therapeutic target in the clinic.

Cardio-oncology: Shared Genetic, Metabolic, and Pharmacologic Mechanism.

PURPOSE OF REVIEW: The article aims to investigate the complex relationship between cancer and cardiovascular disease (CVD), with a focus on the effects of cancer treatment on cardiac health. RECENT FINDINGS: Advances in cancer treatment have improved long-term survival rates, but CVD has emerged as a leading cause of morbidity and mortality in cancer patients. The interplay between cancer itself, treatment methods, homeostatic changes, and lifestyle modifications contributes to this comorbidity. Recent research in the field of cardio-oncology has revealed common genetic mutations, risk factors, and metabolic features associated with the co-occurrence of cancer and CVD. This article provides a comprehensive review of the latest research in cardio-oncology, including common genetic mutations, risk factors, and metabolic features, and explores the interactions between cancer treatment and CVD drugs, proposing novel approaches for the management of cancer and CVD.

STING regulates the transformation of the proinflammatory macrophage phenotype by HIF1A into autoimmune myocarditis.

Macrophages play an essential role in the pathogenesis of autoimmune myocarditis, but the molecular mechanism remains largely unknown. Here, the role of Stimulator of interferon gene (Sting) in autoimmune myocarditis was investigated. Six-week-old male BALB/c mice received two subcutaneous injections of 250 µg α-MyHC peptide to establish experimental autoimmune myocarditis (EAM). With single-cell RNA sequencing analysis of cardiac immune (Cd45+) cells, Sting was found to initiate proinflammatory macrophage differentiation related to the acute EAM phase. Furthermore, proinflammatory macrophages contribute to the pathogenesis of EAM via hypoxia-inducible factor-1α (Hif1α). A higher expression level of Sting was detected in macrophages from myocarditis, which was positively correlated with Hif1α expression. Single-stranded DNA (ssDNA) accumulation in macrophages in myocarditis was observed in the hearts of EAM mice. Pharmacological blockade of STING by C-176 (a specific inhibitor) ameliorated the inflammatory response of EAM and reduced proinflammatory molecule (Ifn-ß, Tnf-α, Ccl2, and F4/80) expression and Hif1α expression. In vitro studies revealed that ssDNA activated the expression of Sting; in turn, Sting accelerated proinflammatory molecule expression in mouse macrophages. Inhibition of Hif1α expression could reduce Sting-associated cardiac inflammation and proinflammatory molecule expression. In addition, the expression of STING and ssDNA accumulation in macrophages were observed in human autoimmune myocarditis heart samples. STING activated proinflammatory macrophage via HIF1A, promoting the development of autoimmune myocarditis. The STING signaling pathway might provide a novel mechanism of autoimmune myocarditis and serve as a potential therapeutic target for autoimmune myocarditis patients.

Single-cell RNA sequencing to identify cellular heterogeneity and targets in cardiovascular diseases: from bench to bedside.

The mechanisms of cardiovascular diseases (CVDs) remain incompletely elucidated. Single-cell RNA sequencing (scRNA-seq) has enabled the profiling of single-cell transcriptomes at unprecedented resolution and throughput, which is critical for deciphering cardiovascular cellular heterogeneity and underlying disease mechanisms, thereby facilitating the development of therapeutic strategies. In this review, we summarize cellular heterogeneity in cardiovascular homeostasis and diseases as well as the discovery of potential disease targets based on scRNA-seq, and yield new insights into the promise of scRNA-seq technology in precision medicine and clinical application.

Changes of Plasma Tris(hydroxymethyl)aminomethane and 5-Guanidino-3-methyl-2-oxopentanoic Acid as Biomarkers of Heart Remodeling after Left Ventricular Assist Device Support.

Cardiac function is closely related to heart metabolism. Heart failure patients undergoing LVAD support have shown varying degrees of remodeling of both cardiac function and morphology. However, the metabolic changes in patients with different outcomes are unclear. This study aimed to identify metabolic differences and evaluate metabolomics-based biomarkers in patients with non-improved/improved cardiac function after LVAD support. Sixteen patients were enrolled in this study. Plasma samples were analyzed by using untargeted metabolomic approaches. Multivariate statistical analysis and a Mann-Whitney U-test was performed to clarify the separation in metabolites and to identify changes in plasma metabolites between the two groups, respectively. The efficacy of candidate biomarkers was tested by the area under the curve receiver operating characteristic curve. Using the Metabolomics Standards Initiative level 2, a total of 1542 and 619 metabolites were detected in the positive and negative ion modes, respectively. Enrichment analysis showed that metabolites in improved cardiac function patients were mainly involved in carbohydrate metabolism and amino acid metabolism. Metabolites from non-improved cardiac function patients were mainly involved in hormone metabolism. Furthermore, we found tris(hydroxymethyl)aminomethane and 5-guanidino-3-methyl-2-oxopentanoic acid could serve as biomarkers to predict whether a patient's cardiac function would improve after LVAD support.

Cellular Landscapes of Nondiseased Human Cardiac Valves From End-Stage Heart Failure-Explanted Heart.

BACKGROUND: Exploring the mechanisms of valvular heart disease at the cellular level may be useful to identify new therapeutic targets; however, the comprehensive cellular landscape of nondiseased human cardiac valve leaflets remains unclear. METHODS: The cellular landscapes of nondiseased human cardiac valve leaflets (5 aortic valves, 5 pulmonary valves, 5 tricuspid valves, and 3 mitral valves) from end-stage heart failure patients undergoing heart transplantation were explored using single-cell RNA sequencing. Bioinformatics was used to identify the cell types, describe the cell functions, and investigate cellular developmental trajectories and interactions. Differences among the 4 types of cardiac valves at the cellular level were summarized. Pathological staining was performed to validate the key findings of single-cell RNA sequencing. An integrative analysis of our single-cell data and published genome-wide association study-based and bulk RNA sequencing-based data provided insights into the cell-specific contributions to calcific aortic valve diseases. RESULTS: Six cell types were identified among 128 412 cells from nondiseased human cardiac valve leaflets. Valvular interstitial cells were the largest population, followed by myeloid cells, lymphocytes, valvular endothelial cells, mast cells, and myofibroblasts. The 4 types of cardiac valve had distinct cellular compositions. The intercellular communication analysis revealed that valvular interstitial cells were at the center of the communication network. The integrative analysis of our single-cell RNA sequencing data revealed key cellular subpopulations involved in the pathogenesis of calcific aortic valve diseases. CONCLUSIONS: The cellular landscape differed among the 4 types of nondiseased cardiac valve, which might explain their differences in susceptibility to pathological remodeling and valvular heart disease.

N-Acetylcysteine, an ROS Inhibitor, Alleviates the Pathophysiology of Hyperthyroidism-Induced Cardiomyopathy via the ROS/Ca2+ Pathway.

Hyperthyroidism is common and can induce cardiomyopathy, but there is no effective therapeutic strategy. The purpose of this study was to investigate the molecular mechanism of hyperthyroidism-induced cardiomyopathy (HTC) and the effect of N-acetylcysteine (NAC), an ROS inhibitor, on the pathophysiology of HTC in vivo and in vitro. Compared with those in the control groups in vivo and in vitro, TT3 and TT4 were significantly increased, the structure of myocardial cells was enlarged and disordered, and interstitial fibrosis and the apoptosis of myocardial cells were markedly increased in the L-Thy group. The ROS and inflammatory response were increased in the hyperthyroidism group. In the NAC group, the contents of TT3 and TT4 were decreased, the myocardial cell structure was slightly disturbed, fibrosis and apoptosis were significantly reduced, and the ROS level and inflammatory response were significantly reduced. Interestingly, L-Thy decreased the viability of fibroblasts and H9c2 cells, suggesting that L-Thy-induced fibrosis was not caused by the proliferation of fibroblasts. The molecular mechanism of HTC could be explained by the fact that L-Thy could cause cardiac hypertrophy, inflammation, and fibrosis by regulating the Ca2+/calpain/Rcan1-dependent signalling pathway, the Ca2+/Rcan1/NF-κB/p65-dependent signalling pathway, and the Ca2+/ROS/Bcl-2/caspase-3-dependent signalling pathway. In conclusion, NAC can alleviate the pathophysiology of hyperthyroidism-induced cardiomyopathy, probably by regulating the ROS/Ca2+-dependent pathway.

Single-cell transcriptomic identified HIF1A as a target for attenuating acute rejection after heart transplantation.

Acute rejection (AR) is an important contributor to graft failure, which remains a leading cause of death after heart transplantation (HTX). The regulation of immune metabolism has become a new hotspot in the development of immunosuppressive drugs. In this study, Increased glucose metabolism of cardiac macrophages was found in patients with AR. To find new therapeutic targets of immune metabolism regulation for AR, CD45+ immune cells extracted from murine isografts, allografts, and untransplanted donor hearts were explored by single-cell RNA sequencing. Total 20 immune cell subtypes were identified among 46,040 cells. The function of immune cells in AR were illustrated simultaneously. Cardiac resident macrophages were substantially replaced by monocytes and proinflammatory macrophages during AR. Monocytes/macrophages in AR allograft were more active in antigen presentation and inflammatory recruitment ability, and glycolysis. Based on transcription factor regulation analysis, we found that the increase of glycolysis in monocytes/macrophages was mainly regulated by HIF1A. Inhibition of HIF1A could alleviate inflammatory cells infiltration in AR. To find out the effect of HIF1A on AR, CD45+ immune cells extracted from allografts after HIF1A inhibitor treatment were explored by single-cell RNA sequencing. HIF1A inhibitor could reduce the antigen presenting ability and pro-inflammatory ability of macrophages, and reduce the infiltration of Cd4+ and Cd8a+ T cells in AR. The expression of Hif1α in AR monocytes/macrophages was regulated by pyruvate kinase 2. Higher expression of HIF1A in macrophages was also detected in human hearts with AR. These indicated HIF1A may serve as a potential target for attenuating AR.

Single-Cell Transcriptomic Atlas of Different Human Cardiac Arteries Identifies Cell Types Associated With Vascular Physiology.

[Figure: see text].

Phenotypes of Cardiovascular Diseases: Current Status and Future Perspectives.

Cardiovascular diseases (CVDs) are a large group of diseases and have become the leading cause of morbidity and mortality worldwide. Although considerable progresses have been made in the diagnosis, treatment and prognosis of CVD, communication barriers between clinicians and researchers still exist because the phenotypes of CVD are complex and diverse in clinical practice and lack of unity. Therefore, it is particularly important to establish a standardized and unified terminology to describe CVD. In recent years, there have been several studies, such as the Human Phenotype Ontology, attempting to provide a standardized description of the disease phenotypes. In the present article, we outline recent advances in the classification of the major types of CVD to retrospectively review the current progresses of phenotypic studies in the cardiovascular field and provide a reference for future cardiovascular research.

Single-Cell RNA Sequencing to Dissect the Immunological Network of Autoimmune Myocarditis.

BACKGROUND: Myocarditis can develop into dilated cardiomyopathy, which may require heart transplantation. The immunological network of myocarditis phases remains unknown. This study aimed to investigate the immunological network during the transition from myocarditis to cardiomyopathy and to identify the genes contributing to the inflammatory response to myocarditis. METHODS: Mice were treated with myosin heavy chain-α peptides to generate an experimental autoimmune myocarditis (EAM) model. We performed single-cell RNA sequencing analysis of Cd45+ cells extracted from mouse hearts during different EAM phases, including normal control, acute inflammatory, subacute inflammatory, and myopathy phases. Human heart tissues were collected from the surgically removed hearts of patients who had undergone heart transplantation. RESULTS: We identified 26 cell subtypes among 34 665 cells. Macrophages constituted the main immune cell population at all disease phases (>60%), and an inflammation-associated macrophage cluster was identified in which the expression of Hif1a-regulated genes was upregulated. The neutrophil population was increased after the induction of EAM, and neutrophils then released Il-1 to participate in the EAM process. T cells were observed at the highest percentage at the subacute inflammatory phase. T-helper 17 cells, in which the expression of Hif1a-regulated genes was upregulated, constituted the main T-cell population detected at the acute inflammatory phase, whereas regulatory T cells were the main T-cell population detected at the subacute inflammatory phase, and γδ T cells releasing Il-17 were the main T-cell population observed at the myopathy phase. Moreover, the Hif1a expression level correlated with the extent of inflammation. In addition, PX-478 could alleviate the inflammatory responses of the different EAM phases. Last, HIF1A was expressed at higher levels in patients with acute autoimmune myocarditis than in patients with dilated cardiomyopathy and healthy control subjects. CONCLUSIONS: We present here a comprehensive single-cell landscape of the cardiac immune cells in different EAM phases. In addition, we elucidate the contribution of Hif1a to the inflammatory response through the regulation of immune cell activity, particularly of macrophage cluster 2 and T-helper 17 cells. Moreover, an Hif1a inhibitor alleviated inflammatory cell infiltration of the EAM model and may serve as a potential therapeutic target in the clinic.

Multi-level transcriptome sequencing identifies COL1A1 as a candidate marker in human heart failure progression.

BACKGROUND: Heart failure (HF) has been recognized as a global pandemic with a high rate of hospitalization, morbidity, and mortality. Although numerous advances have been made, its representative molecular signatures remain largely unknown, especially the role of genes in HF progression. The aim of the present prospective follow-up study was to reveal potential biomarkers associated with the progression of heart failure. METHODS: We generated multi-level transcriptomic data from a cohort of left ventricular heart tissue collected from 21 HF patients and 9 healthy donors. By using Masson staining to calculate the fibrosis percentage for each sample, we applied lasso regression model to identify the genes associated with fibrosis as well as progression. The genes were further validated by immunohistochemistry (IHC) staining in the same cohort and qRT-PCR using another independent cohort (20 HF and 9 healthy donors). Enzyme-linked immunosorbent assay (ELISA) was used to measure the plasma level in a validation cohort (139 HF patients) for predicting HF progression. RESULTS: Based on the multi-level transcriptomic data, we examined differentially expressed genes [mRNAs, microRNAs, and long non-coding RNAs (lncRNAs)] in the study cohort. The follow-up functional annotation and regulatory network analyses revealed their potential roles in regulating extracellular matrix. We further identified several genes that were associated with fibrosis. By using the survival time before transplantation, COL1A1 was identified as a potential biomarker for HF progression and its upregulation was confirmed by both IHC and qRT-PCR. Furthermore, COL1A1 content ≥ 256.5 ng/ml in plasma was found to be associated with poor survival within 1 year of heart transplantation from heart failure [hazard ratio (HR) 7.4, 95% confidence interval (CI) 3.5 to 15.8, Log-rank p value < 1.0 × 10- 4]. CONCLUSIONS: Our results suggested that COL1A1 might be a plasma biomarker of HF and associated with HF progression, especially to predict the 1-year survival from HF onset to transplantation.