Loss of sarcolipin results in atrial remodeling
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Shanmugam Mayilvahanan
PROVIDER: E-GEOD-23403 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Sarcolipin (SLN) is a key regulator of SERCA pump in atria. To determine the role of SLN in atrial Ca2+ homeostasis, we have generated a SLN null (sln-/-) mouse model. Ablation of SLN results in increased SR Ca2+ load and Ca2+ transients in atria. Further, loss of SLN results in electrophysiological and strcutural remodeling of atria.
2010-11-01 | GSE23403 | GEO
Project description:Evidence that lysosomes are important in cardiac physiology and pathology is now emerging. We describe a label-free method suitable for small cardiac tissue biopsies based on a density-separated fractionation protocol, which allows us to study endo-lysosomal (EL) proteins in guinea pig atria. The three most relevant density gradient fractions obtained were analysed using Western Blot, enzyme activity assay and MS/MS peptide analysis (adapted discontinuous Percoll, and sucrose differential density gradient). These fractions comprise whole tissue lysate; sarcoplasmic reticulum (SR), mitochondrial proteins (Mito) (1.3 g/mL); and ‘pure’ EL with negligible contamination from SR or Mito (1.04 g/mL). Kyoto Encyclopedia of Genes and Genomes, Reactome, Panther and Gene Ontology pathway analysis showed good coverage of RAB proteins, lysosomal cathepsins (including cardiac-specific cathepsin D) in the purified EL fraction. The most significant EL proteins recovered included catalytic activity proteins. We thus present a comprehensive protocol and dataset of guinea-pig atrial EL focussed organelle proteomics
2021-09-09 | PXD021277 | Pride
Project description:Obscurins are giant, modular, cytoskeletal proteins that regulate striated muscle structure and function. Immunoglobulin domains 58/59 (Ig58/59) of obscurin interact with diverse proteins including titin variants and phospholamban. Mutations within Ig58/59 that alter these binding interactions have been linked to the development of myopathy in humans, underscoring the pathophysiological significance of this module. We previously generated a constitutive deletion mouse model, Obscn-ΔIg58/59, that expresses obscurin lacking Ig58/59 and comprehensively characterized the effects of this deletion on cardiac morphology and function through aging. Our findings demonstrated that Obscn-ΔIg58/59 male animals develop severe arrhythmia characterized by spontaneous atrial fibrillation/junctional escape by 6-months of age, with atrial enlargement and ventricular remodeling manifesting by 12-months. Herein, we aim to mechanistically evaluate the impact of the Ig58/59 deletion in atria at the cellular level and determine the molecular basis for atrial enlargement and arrhythmia due to the physiological process of aging. Ultrastructural evaluation of sedentary aging male Obscn-ΔIg58/59 atria revealed prominent Z-disk streaming and misalignment. More importantly, Obscn-ΔIg58/59 atrial cardiomyocytes exhibited increased Ca2+ spark frequency and age-specific alterations in Ca2+ cycling kinetics and sarcoplasmic reticulum Ca2+ content that preceded those observed in Obscn-ΔIg58/59 ventricular cardiomyocytes. Proteomic and phospho-proteomic analyses revealed extensive and novel alterations in the expression and phosphorylation profile of major cytoskeletal proteins, Ca2+ regulators, and Z-disk associated protein complexes in Obscn-ΔIg58/59 atria through aging that likely underlie the observed atrial pathologies. These studies are the first to evaluate the role of obscurin in atria and to reveal chamber-specific molecular alterations due to Ig58/59 deletion. Moreover, our findings provide new molecular insights into a genetic model of spontaneous atrial fibrillation and remodeling where atrial dysfunction precedes ventricular maladaptation.
2023-04-11 | PXD028904 | Pride
Project description:To understand the molecular change occurring in the atria during obstructive sleep apnea, we have implemented a rat model of OSA involving the surgical implantation of a tracheal obstructive device, allowing the rats to remain conscious and free-roaming throughout 2 weeks of apnea administration. Rats were divided into severe and moderate apnea groups, receiving a 23 second or 13 second apneas per minute, respectively. The two-dimensional polyacrylamide gel electrophoresis (2D PAGE) of atrial homogenates to compare the dysregulations in the protein pattern in severe and moderate apnea when compared to control.
2019-02-21 | PXD011181 | Pride
Project description:Atrial specific knockout of Nkx2-5 results in hyperplastic atria with ASD and conduction defects. To examine how Nkx2-5 regulates cardiac proliferation at late gestational stages, RNA-seq was performed. Examination of expression profile of 2 Nkx2-5-null atria and 3 controls
2014-10-31 | E-GEOD-52080 | biostudies-arrayexpress
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:Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia treatable with antiarrhythmic drugs, but patient responses are highly variable. Human induced pluripotent stem cell-derived atrial cardiomyocytes (iPSC-aCMs) are useful for discovering precision therapeutics, but current platforms yield an immature cellular phenotype and are not easily scalable for high-throughput screening. Here, we report that primary adult atrial, but not ventricular, fibroblasts induced greater functional iPSC-aCM maturation, partly through connexin-40 and ephrin-B1 signaling. We developed a protein patterning process within industry-standard multiwell plates to engineer patterned co-culture (PC) of iPSC-aCMs and atrial fibroblasts that significantly enhanced iPSC-aCM structural, electrical, contractile, and metabolic maturation for 6+ weeks versus conventional mono-/co-cultures. PC displayed greater sensitivity for detecting drug efficacy than monocultures, and enabled the modeling and pharmacological or gene editing treatment of an AF-like electrophysiological phenotype due to a sodium channel mutation. In conclusion, PC is useful to elucidate heterotypic cell signaling in the atria, drug screening, and to model AF.
2024-01-19 | GSE239321 | GEO
Project description:Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia treatable with antiarrhythmic drugs, but patient responses are highly variable. Human induced pluripotent stem cell-derived atrial cardiomyocytes (iPSC-aCMs) are useful for discovering precision therapeutics, but current platforms yield an immature cellular phenotype and are not easily scalable for high-throughput screening. Here, we report that primary adult atrial, but not ventricular, fibroblasts induced greater functional iPSC-aCM maturation, partly through connexin-40 and ephrin-B1 signaling. We developed a protein patterning process within industry-standard multiwell plates to engineer patterned co-culture (PC) of iPSC-aCMs and atrial fibroblasts that significantly enhanced iPSC-aCM structural, electrical, contractile, and metabolic maturation for 6+ weeks versus conventional mono-/co-cultures. PC displayed greater sensitivity for detecting drug efficacy than monocultures, and enabled the modeling and pharmacological or gene editing treatment of an AF-like electrophysiological phenotype due to a sodium channel mutation. In conclusion, PC is useful to elucidate heterotypic cell signaling in the atria, drug screening, and to model AF.
2024-01-19 | GSE239317 | GEO
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: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). Keywords = human myocardium Keywords = atrial fibrillation Keywords = sinus rhythm Keywords = left ventricular gene expression Keywords: other
2005-05-13 | GSE2240 | GEO