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Gene expression profiles in Sirt1/PPARalpha bigenic mice

ABSTRACT: Cardiac-specific PPARalpha transgenic (Tg-PPARalpha) mice show mild cardiac hypertrophy and systolic dysfunction. The failing heart phenotypes observed in Tg-PPARalpha are exacerbated by crossing with cardiac-specific Sirt1 transgenic (Tg-Sirt1) mice, whereas Tg-Sirt1 mice themselves do not show any cardiac hypertrophy or systolic dysfunction. To investigate the mechanism leading to the failing heart phenotypes in TgPPARalpha/Tg-Sirt1 bigenic mice, microarray analyses were performed. The microarray analyses revealed that many ERR target genes were downregulated in Tg-PPARalpha and in Tg-Sirt1, and they were further downregulated in the Tg-PPARalpha/Tg-Sirt1 bigenic mice.

ORGANISM(S): Mus musculus

PROVIDER: GSE33101 | GEO | 2011/12/01

SECONDARY ACCESSION(S): PRJNA149333

REPOSITORIES: GEO

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Project description:Full Title: Transition from Compensated Hypertrophy to Systolic Heart Failure in the Spontaneously Hypertensive Rat: Structure, Function, and Transcript Analysis Gene expression changes and left ventricular remodeling associated with the transition to systolic heart failure (HF) were determined in the spontaneously hypertensive rat (SHR). By combining transcriptomics of left ventricles from six SHR with HF with changes in function and structure we aimed to better understand the molecular events underlying the onset of systolic HF compared to six age-matched, SHR with compensated hypertrophy. Left ventricle (LV) ejection fraction was depressed (82Â±4 to 52Â±3 %) in compensated vs. failing animals.Â Systolic blood pressure decreased and LV end-diastolic and systolic volume increased with HF.Â Failing SHR hearts also demonstrated increases in left and right ventricular mass relative to non-failing SHRs.Â Â LV papillary muscle force development and shortening velocity decreased, Î²-adrenergic responsiveness was depressed, myocardial stiffness and myocardial fibrosis increased with HF relative to non-failing animals. Initial micro-array analysis revealed that 1,431 transcripts were differentially expressed with HF compared to non-failing SHR (p<0.05). Of the identified transcripts, lipopolysaccharide binding protein, the most highly expressed transcript with HF, was negatively correlated to myocardial force while elevated expression of the collagen cross-linking enzyme lysyl oxidase correlated positively with muscle stiffness. Besides these individual transcripts, gene set enrichment analysis (GSEA) identified multiple enriched pathways with HF, most prominent of the altered signaling pathways involved TGF-Î² and insulin signaling. GESA analysis additionally identified altered gene sets involving inflammation, oxidative stress, cell degradation and cell death, among others (all p<0.01). In contrast to diastolic HF where few transcripts are reported to be altered, our data indicate multiple genes and pathways involved in a variety of biological processes characterize the onset of systolic HF, consistent with many functional and structural changes present in the failing hypertensive heart. Comprehensive gene expression profiling of heart failure Rat model vs control.

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Gene expression profiles in Sirt1/PPARalpha bigenic mice

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