Gender dependent differences in molecular electrophysiological targets in failing and nonfailing human hearts
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE33165 | GEO | 2012/02/01
SECONDARY ACCESSION(S): PRJNA149239
REPOSITORIES: GEO
Similar Datasets
Project description:Previous epidemiological studies have shown that males tend to have an increased overall lifetime risk of developing atrial fibrillation (AF), whereas females tend to be more susceptible to the development of ventricular tachyarrhythmias resulting from long-QT syndrome and drug-induced Torsades de Pointes. In this study, we compared the transcript-level expression of 89 ion channel subunits, calcium handling proteins, and other transcription factors in the left atria (LA) and ventricles (LV) of human hearts of both genders. Total RNA from the LA and LV of failing male (n=9), failing female (n=7), nonfailing male (n=9), and nonfailing female (n=9) hearts was probed using a custom-designed Taqman gene array from Applied Biosystems. Tissues from LA (n=22), LV (n=22), LV endocardium (n=12), and LV epicardium (n=12) were analyzed by the Applied Biosystems SDS 2.3 software using the threshold cycle (Ct) relative quantification method with GAPDH as an endogenous control.
2012-02-01 | E-GEOD-33165 | biostudies-arrayexpress
Project description:Note this data set has identical data files: Files GSM40994.txt and GSM40995.txt. GSE2240 contains two different experimental subsets:; 1) Comparison of atrial and ventricular gene expression (atrial tissue of patients with sinus rhythm vs. human left ventricular non-failing myocardium); The purpose of our investigation was to identify the transcriptional basis for ultrastructural and functional specialization of human atria and ventricles. Using exploratory microarray analysis (Affymetrix U133A+B), we detected 11,740 transcripts expressed in human heart, representing the most comprehensive report of the human myocardial transcriptome to date. Variation in gene expression between atria and ventricles accounted for the largest differences in this data set, as 3.300 and 2.974 transcripts showed higher expression in atria and ventricles, respectively. Functional classification based on Gene Ontology identified chamber-specific patterns of gene expression and provided molecular insights into the regional specialization of cardiomyocytes, correlating important functional pathways to transcriptional activity: Ventricular myocytes preferentially express genes satisfying contractile and energetic requirements, while atrial myocytes exhibit specific transcriptional activities related to neurohumoral function. In addition, several pro-fibrotic and apoptotic pathways were concentrated in atrial myocardium, substantiating the higher susceptibility of atria to programmed cell death and extracellular matrix remodelling observed in human and experimental animal models of heart failure. Differences in transcriptional profiles of atrial and ventricular myocardium thus provide molecular insights into myocardial cell diversity and distinct region-specific adaptations to physiological and pathophysiological conditions (Barth AS et al., Eur J Physiol, 2005). 2) Comparison of atrial gene expression in patients with permanent atrial fibrillation and sinus rhythm. Atrial fibrillation is associated with increased expression of ventricular myosin isoforms in atrial myocardium, regarded as part of a dedifferentiation process. Whether re-expression of ventricular isoforms in atrial fibrillation is restricted to transcripts encoding for contractile proteins is unknown. Therefore, this study compares atrial mRNA expression in patients with permanent atrial fibrillation to atrial mRNA expression of patients with sinus rhythm as well as to ventricular gene expression using Affymetrix U133 arrays. In atrial myocardium, we identified 1.434 genes deregulated in atrial fibrillation, the majority of which, including key elements of calcium-dependent signaling pathways, displayed down-regulation. Functional classification based on Gene Ontology provided the specific gene sets of the interdependent processes of structural, contractile and electrophysiological remodeling. In addition, we demonstrate for the first time a prominent up-regulation of transcripts involved in metabolic activities, suggesting an adaptive response to an increased metabolic demand in fibrillating atrial myocardium. Ventricular-predominant genes were five times more likely to be up-regulated in atrial fibrillation (174 genes up-regulated, 35 genes down-regulated), while atrial-specific transcripts were predominantly down-regulated (56 genes up-regulated, 564 genes down-regulated). Overall, in atrial myocardium, functional classes of genes characteristic of ventricular myocardium were found to be up-regulated (e.g. metabolic processes) while functional classes predominantly expressed in atrial myocardium were down-regulated in atrial fibrillation (e.g. signal transduction and cell communication). Therefore, dedifferentiation with adoption of a ventricular-like signature is a general feature of the fibrillating atrium, uncovering the transcriptional response pattern in pmAF (Barth AS et al., Circ Res, 2005).
2007-10-27 | E-GEOD-2240 | biostudies-arrayexpress
Project description:Background: Atrial fibrillation (AF) causes atrial remodeling, and the left atrium (LA) is the favored substrate for maintaining AF. However, it remains unclear if AF remodels both atria differently and contributes to LA arrhythmogenesis and thrombogenesis. Results: AF was associated with differential LA-to-RA gene expression related to specific ion channels and pathways as well as upregulation of thrombogenesis-related genes in the LA appendage. Targeting the molecular mechanisms underlying the LA-to-RA difference and AF-related remodeling in the LA appendage may help provide new therapeutic options in treating AF and preventing thromboembolism in AF. Paired left atrial and right atrial specimens were obtained from 13 patients with persistent AF receiving valvular surgery. The Paired specimens were sent for microarray comparison. Selected results were validated by quantitative real time-PCR (q-PCR) and Western blotting. Ultrastructural changes in the atria were evaluated by immunohistochemistry.
2016-08-09 | E-GEOD-79768 | biostudies-arrayexpress
Project description:Background: Atrial fibrillation (AF) causes atrial remodeling, and the left atrium (LA) is the favored substrate for maintaining AF. However, it remains unclear if AF remodels both atria differently and contributes to LA arrhythmogenesis and thrombogenesis. Results: AF was associated with differential LA-to-RA gene expression related to specific ion channels and pathways as well as upregulation of thrombogenesis-related genes in the LA appendage. Targeting the molecular mechanisms underlying the LA-to-RA difference and AF-related remodeling in the LA appendage may help provide new therapeutic options in treating AF and preventing thromboembolism in AF.
2016-08-09 | GSE79768 | GEO
Project description:Atrial Fibrillation (AF), an abnormal heart rhythm characterized by the rapid and irregular beating of the atria, is the most common arrhythmia with heavy global burdens. The present project aimed to characterized the feature of metabolites in feces of AF patients by using LC-MS.
2018-12-27 | ST001208 | MetabolomicsWorkbench
Project description:Background: Inflammation is closely related to atrial fibrillation (AF), in which macrophages play an important role as immune cells. Recent studies have shown that macrophages participate in the electron conduction in the heart, indicating that they have electrophysiological characteristics. However, whether the electrophysiology of macrophages is associated with AF remained unclear. Methods: In the present study, we investigated the electrophysiological changes in macrophages using patch-clamping after tachypacing to mimic AF. RNA-seq was performed to investigate the expression change of atrial myocytes after tachypacing. Rapid atrial stimulation was performed to measure the AF incidence in macrophages-specific CX43 knockout mice. Results: We found that the APD90 and the ICa,L were reduced. Further, we found that tachypacing atrial myocytes led to the secretion of Wnt 7a, further inhibiting the expression of CACNA1C in macrophages. Moreover, the knockout of CX43 in macrophages decreased the incidence of AF in a chronic inflammation mice model. Conclusion: Altogether, these results demonstrated that the electrophysiology of macrophages was related to the development of AF and might be a potential therapeutic target for AF.
2024-04-10 | GSE263301 | GEO
Project description:Sustained atrial tachycardia leads to multiple molecular and cellular effects collectively defined as atrial tachycardia remodeling (ATR). ATR is thought to play a major role in the self-perpetuating nature of atrial fibrillation (AF) and has been a subject of intense research in large mammalian models of AF. Recently, rodents are increasingly used to gain insight on the pathophysiology AF. However, little is known regarding the effects of rapid pacing on the atria of rats and mice mainly due to technical challenges in electrophysiological studies of unanesthetized rodents. Using an implantable device for electrophysiological studies in unanesthetized rodents we examine, on a daily basis, the effects of continuous rapid atrial pacing (RAP) for at least 4 consecutive days on the developed AF substrate of Sprague-Dawley rats and C57BL6 mice. AF induction protocol consisted 10 aggressive bursts (20 seconds, double diastolic threshold, 10 ms cycle length [CL]). This protocol failed to induce AF at baseline in both species, but repeatedly induced AF episodes in rats following 2 days of sustained RAP. Microarray study of left atrial tissue from rats exposed for 2 days to RAP (70 ms CL) vs control pacing (140 ms CL) identified 304 differentially expressed genes (155 upregulated and 149 downregulated). Real-time qt-PCR confirmed the validity of the microarray. Enrichment analysis and comparison with a dataset of atrial tissue from AF patients revealed indications of increased carbohydrate metabolism, and changes in pathways that are thought to have critical role in human AF including TGF-beta and IL-6 signaling. Among 19 commonly affected genes in comparison with human AF, downregulation of FOXP1 and upregulation of the KCNK2 gene encoding the Kir2.1 potassium channel were conspicuous finding suggesting NFAT activation. Further results in line with NFAT activation included reduced expression of MIR-26, MIR-101, which were linked to upregulation of the KCNK2 in human AF. Our results demonstrate electrophysiological evidence for AF promoting effects of RAP in rats and some important molecular similarities between the effects of RAP in large and small mammalian models. The effects of atrial tachypacing are well documented in large mammals but very little is know regarding the effects of tacypacing on the rodent atria.
2019-08-01 | GSE126711 | GEO
Project description: Not available
| S-EPMC3552854 | biostudies-literature
Project description:Objectives: To test the hypothesis that serine/threonine protein phosphatase type-1 (PP1) is dysregulated in paroxysmal atrial fibrillation (pAF) at the level of its regulatory subunits (R-subunits). Background: AF is the most common sustained cardiac arrhythmia yet current pharmacologic treatment is ineffective. PP1, a major phosphatase in the heart, consists of a catalytic subunit (PP1c) and a large set of R-subunits that confer localization and substrate specificity to the holoenzyme. Previous studies suggest that PP1 is dysregulated in AF but the mechanisms are unknown. Methods: Cardiac lysates were co-immunoprecipitated with anti-PP1c antibody followed by mass spectrometry-based (quantitative) profiling of associated R-subunits. Subsequently, label-free quantification was used to evaluate altered R-subunit-PP1c interactions in pAF patients. R-subunits with altered binding to PP1c in pAF were further validated using qRT-PCR, Western blotting (WB), immunocytochemistry, and co-immunoprecipitation. Results: 135 and 78 putative PP1c-interactors were captured respectively from mouse ventricles and human atria, with many previously unreported interactors with conserved PP1c-docking motifs. Increases in binding were found between PP1c and PPP1R7, CSDA, and PDE5A in pAF patients, with CSDA and PDE5A being novel interactors validated by bioinformatics, immunocytochemistry and co-immunoprecipitation. WB confirmed that these upregulated associations cannot be ascribed to changes in global protein expression alone. Conclusion: Subcellular heterogeneity in PP1 activity and downstream protein phosphorylation in AF may be attributed to alterations in PP1c-R-subunits interactions, which impair PP1 targeting to proteins involved in electrical and Ca2+-remodeling. This represents a novel concept in AF pathogenesis and provides highly-specific drug targets for treating AF.
2015-03-30 | PXD000697 | Pride
Project description:Background: Chronic atrial fibrillation (AF) is a complication associated with the dilated atria of patients with valvular heart disease and contributes to worsened pathology. Methods and Results: Using microarray technology, we examined microRNA (miR) expression profiles in right and left atrial appendage tissue from valvular heart disease (VHD) patients. Right atrial appendage from patients undergoing coronary artery bypass grafting (CABG) and left atrial (LA) appendage from healthy hearts not used for transplant were used as controls. VHD induced different changes in miR expression in LA compared with right atria (RA). Fifty-two (52) miRs were altered by VHD in LA, compared with 5 in RA tissue. There was no detectable effect of chronic AF on miR expression in LA tissue, but miR expression in RA was strongly influenced by AF, with 47 miRs showing differential expression. LA volume correlated with miR expression changes in both LA and RA, but the affected miRs were different for the two atrial groups. Conclusions: VHD and AF influence miR expression patterns in LA and RA, but these are affected differently by disease progression and by the development of AF. These findings provide new insights into the progression of VHD. RA tissue is not a useful surrogate for LA in studies of mitral valve disease. 34 arrays from either the left or right atrium from patients with Valvular Heart Disease (VHD), patients undergoing coronary artery bypass grafting (CABG), or healthy controls. Arrays in this series were generated on V2 and V3 Agilent microRNA arrays and analysed in combination.
2011-12-21 | E-GEOD-28954 | biostudies-arrayexpress