Journal Article

Epigenetic regulation of mitochondrial fission and cardiac fibrosis via sFRP3 promoter methylation

Jiang, Shun-Xiang, Liu, Zhi-Yan, Tao, Hui, Zhou, Ze-Yu, Song, Kai, Zhao, Jian-Yuan, Cao, Wei, Tu, Bin, Lin, Li-Chan

2024

Overview

In the process of cardiac fibrosis, the balance between the Wnt/β-catenin signalling pathway and Wnt inhibitory factor genes plays an important role. Secreted frizzled-related protein 3 (sFRP3), a Wnt inhibitory factor, has been linked to epigenetic mechanisms. However, the underlying role of epigenetic regulation of sFRP3, which is crucial in fibroblast proliferation and migration, in cardiac fibrosis have not been elucidated. Therefore, we aimed to investigate epigenetic and transcription of sFRP3 in cardiac fibrosis. Using clinical samples and animal models, we investigated the role of sFRP3 promoter methylation in potentially enhancing cardiac fibrosis. We also attempted to characterize the underlying mechanisms using an isoprenaline-induced cardiac fibrosis mouse model and cultured primary cardiac fibroblasts. Hypermethylation of sFRP3 was associated with perpetuation of fibroblast activation and cardiac fibrosis. Additionally, mitochondrial fission, regulated by the Drp1 protein, was found to be significantly altered in fibrotic hearts, contributing to fibroblast proliferation and cardiac fibrosis. Epigenetic modification of sFRP3 promoter methylation also influenced mitochondrial dynamics, linking sFRP3 repression to excessive mitochondrial fission. Moreover, sFRP3 hypermethylation was mediated by DNA methyltransferase 3A (DNMT3A) in cardiac fibrosis and fibroblasts, and DNMT3A knockdown demethylated the sFRP3 promoter, rescued sFRP3 loss, and ameliorated the isoprenaline-induced cardiac fibrosis and cardiac fibroblast proliferation, migration and mitochondrial fission. Mechanistically, DNMT3A was shown to epigenetically repress sFRP3 expression via promoter methylation. We describe a novel epigenetic mechanism wherein DNMT3A represses sFRP3 through promoter methylation, which is a critical mediator of cardiac fibrosis and mitochondrial fission. Our findings provide new insights for the development of preventive measures for cardiac fibrosis. Graphical Abstract DNA methyltransferase DNMT3A causes upregulation of sFRP3 methylation levels in cardiac fibrosis and cardiac fibroblasts. Subsequently, sFRP3 downregulation promotes cardiac fibroblast proliferation, migration and mitochondrial fission. DNA methyltransferase DNMT3A repressed sFRP3 to facilitate cardiac fibroblast activation and cardiac fibrosis.

• Publisher: Springer International Publishing,Springer Nature B.V
• Subject: Animal models / Animals / Biochemistry / Biomedical and Life Sciences / Biomedicine / Cell Biology / Cell Proliferation - genetics / Cells, Cultured / Deoxyribonucleic acid / DNA / DNA (Cytosine-5-)-Methyltransferases - genetics / DNA (Cytosine-5-)-Methyltransferases - metabolism / DNA Methylation / DNA methyltransferase / DNA Methyltransferase 3A - genetics / Epigenesis, Genetic / Epigenetics / Fibroblasts / Fibroblasts - metabolism / Fibroblasts - pathology / Fibrosis / Fibrosis - genetics / Fission / Frizzled protein / Frizzled-related protein / Frizzled-related protein 3 / Heart / Humans / Intracellular Signaling Peptides and Proteins - genetics / Intracellular Signaling Peptides and Proteins - metabolism / Isoproterenol / Life Sciences / Male / Methylation / Mice / Mice, Inbred C57BL / mitochondria / Mitochondrial DNA / Mitochondrial Dynamics - genetics / Myocardium - metabolism / Myocardium - pathology / Original / Original Article / Promoter Regions, Genetic - genetics / Proteins / Signal transduction / Wnt protein / β-Catenin