Unknown,Transcriptomics,Genomics,Proteomics

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The AP-1 transcription factor Fosl-2 drives cardiac fibrosis and arrhythmias under immunofibrotic conditions

ABSTRACT: Fibrotic changes in the myocardium and cardiac arrhythmias represent fatal complications in rheumatic disease systemic sclerosis (SSc), however the underlying mechanisms remain elusive. Fos-related antigen-2 (Fosl-2) has been implicated in development of organ fibrosis. Mice overexpressing Fosl-2 (Fosl-2tg) showed interstitial cardiac fibrosis, disorganized connexin43/40 in intercalated discs and deregulated expression of genes controlling conduction system. Fosl-2tg mice developed higher heart rate (HR), prolonged QT intervals, arrhythmias with prevalence of premature ventricular contractions, ventricular tachycardias, II-degree atrio-ventricular blocks and reduced HR variability. Following stimulation with isoproterenol Fosl-2tg mice showed impaired HR response. To assess the role of inflammation in cardiac fibrosis we used Rag2-/-Fosl-2tg mice lacking T/B cells. These mice showed no myocardial fibrosis and ECG abnormalities. Transcriptomics analysis of cardiac Rag-2-/-Fosl-2wt/Rag2-/-Fosl-2tg/Fosl-2tg fibroblasts revealed that systemic inflammation triggered fibrotic and arrhythmogenic alterations while Fosl-2-overexpression mediated profibrotic signature. In human cardiac fibroblasts FOSL-2-overexpression enhanced myofibroblast signature under proinflammatory or profibrotic stimuli. These results demonstrate that under immunofibrotic conditions activator protein 1 transcription factor component Fosl-2 exaggerates myocardial fibrosis, arrhythmias and aberrant response to stress.

INSTRUMENT(S): Illumina iSeq 100

ORGANISM(S): Mus musculus

SUBMITTER: Gabriela Kania

PROVIDER: E-MTAB-12271 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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The AP-1 transcription factor Fosl-2 drives cardiac fibrosis and arrhythmias under immunofibrotic conditions

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