Dysregulation Of Long Non-coding RNA In Cardiac Remodeling Hypertrophic Cardiomyopathy

BackgroudCardiac remodeling refers to increased compensatory hypertrophy and increased cardiac fibrosis in the myocardium due to factors such as increased postload,through decompensation,expansion of myocardium,and ultimately heart failure.Heart failure is the ultimate manifestation of almost all kinds of cardiovascular diseases and also is the leading cause of death from various cardiovascular diseases.Looking for the key regulators of cardiac remodeling and heart failure has been an important area for basic and clinical research in cardiovascular disease.In recent years,non-coding RNAs such as long noncoding RNA(lncRNA)have been found to play an important role in cardiac remodeling and heart failure.The value as an intervention target in the treatment of heart failure is increasing.However,we have known IncRNAs can regulate cardiac remodeling and heart failure,but only a few IncRNAs were known,such as Mhrt,Chaer,and Chast.So large numbers of lncRNAs in the heart and their regulation in cardiovascular diseases remain to be revealed.Therefore,this study aimed to understand the IncRNAs in human cardiac tissue and cardiac fibroblasts by RNA-seq and to find out the most important IncRNAs involved in the regulation of cardiac remodeling and heart failure.MethodsFirst,cardiac tissue was collected from 15 patients with hypertrophic cardiomyopathy(HCM)and 8 normal control cardiac tissues.The Trizol method was used to extract RNA,RNA-seq was used for whole transcriptome sequencing(including IncRNAs and mRNAs),and differentially expressed lncRNAs were screened out(P<0.05).The database was analyzed for its tissue specificity and species conservation.The co-expressed mRNAs were predicted by bioinformatics,and functional cluster analysis was performed using GO,and pathway analysis was performed using KEGG The cardiac-specific expressed IncRNAs were screened by comparison with the NONCODE database(http://www.noncode.org).Next,cardiac fibroblasts were stimulated with 10 ng/mL and 25 ng/mL of TGF-?1,and the expression of ?-SMA was detected by real-time PCR and western blot to detect whether cardiac fibroblasts were activated.Controls and 25 ng/mL TGF-?1 stimulated cardiac fibroblasts for transcriptional sequencing(including IncRNAs and mRNAs)using RNA-seq.Differentially expressed IncRNAs were analyzed by querying databases and bioinformatics.Finally,a comprehensive analysis was performed of all IncRNAs detected by transcriptome sequencing of myocardium and cardiac fibroblasts.Results2206 IncRNAs were detected by transcriptional sequencing of myocardial tissue,of which 711 were significantly changed in hypertrophic myocardium.There were 83 lncRNAs,which FPKM values ? and fold change>1.5,in the hypertrophic myocardium group and/or normal myocardium group,and 40 of them were up-regulated and 43 were down-regulated.Of the 83 abundant and highly differentially expressed IncRNAs,30(36.1%)were specifically cardiac-expressed,suggesting that dysregulation of cardiac-specific LncRNAs may play an important role in cardiac remodeling.Cardiac fibrosis is one of the main features of pathological myocardial remodeling,which is an important cause of increased myocardial stiffness and diastolic dysfunction.To search for cardiac fibrosis-related IncRNAs,we first used TGF-?1 to stimulate human cardiac fibroblasts.Establish an in vitro model of cardiac fibrosis.A total of 11408 IncRNAs were detected by transcriptome sequencing,among which 1406 were significantly different(p<0.05).Due to the differences between in vitro experiments and in vivo disease processes,we next performed a comprehensive analysis of the transcriptomes of myocardial tissue and cardiac fibroblasts,then found that IncRNAs regulate cardiac fibrosis in humans.Results limitated 1462 IncRNAs were detected in myocardial tissue and in vitro cardiac fibroblasts,134 of which had significant differences(p<0.05),and 55 lncRNAs have the same change under conditions of disease and induced cardiac fibrosis in vitro,of which 24 were up-regulated and 31 were down-regulated.The functional cluster analysis of the IncRNAs co-expressed mRNAs showed that it is mainly involved in biological processes such as response to endogenous stimulus,cell differentiation,and transcriptional regulation.Analysis of the KEGG pathway has been shown to be associated with Notch signaling and arrhythmogenic right ventricular cardiomyopathy.It is suggested that IncRNAs may participate in the regulation of cardiac remodeling by participating in the regulation of cardiac fibrosis.ConclusionsThis study for the first time clearly identified the IncRNA expression profiles of myocardial tissue and cardiac fibroblasts in patients with hypertrophic cardiomyopathy;and discovered a variety of IncRNAs that may regulate cardiac remodeling and cardiac fibrosis,The regulation mechanisms of these genes need further experimental validation.