Dapagliflozin Suppresses High Glucose-Induced Proliferation, Oxidative Stress, and Fibrosis by Reducing Mettl3-Induced m6A Modification in Marcks mRNA.

Diabetic cardiomyopathy (DCM) is a common and severe complication of Diabetes mellitus (DM). Dapagliflozin (DAPA) is an oral anti-diabetic drug worldwide for the treatment of type 2 DM. However, the action and mechanism of DAPA in cardiac fibrosis during DCM remain vague. Primary cardiac fibroblasts (CFs) were incubated with high glucose (HG) in vitro. Cell proliferation was detected by MTT and EdU assays. Oxidative stress was evaluated by determining the production of reactive oxygen species and malondialdehyde. Cell fibrosis was assessed by detecting fibrosis-related proteins by western blotting. Levels of Mettl3 (Methyltransferase 3) and Marcks (myristoylated alanine-rich C kinase substrate) were measured using qRT-PCR and western blotting. The m6A modification profile was determined by methylated RNA immunoprecipitation assay and the interaction between Mettl3 and Marcks was verified using dual-luciferase reporter and RIP assays. DAPA treatment alleviated HG-induced proliferation, oxidative stress, and fibrosis in CFs. HG promoted the expression of Mettl3 in CFs. Knockdown of Mettl3 reversed HG-induced proliferation, oxidative stress, and fibrosis in CFs; moreover, forced expression of Mettl3 abolished the protective effects of DAPA on CFs under HG condition. Mechanistically, Mettl3 interacted with Marcks in CFs and induced Marcks mRNA m6A modification. HG induced high expression of Marcks in CFs. The overexpression of Marcks could counteract DAPA or Mettl3 knockdown-evoked inhibitory effects on CF proliferation, oxidative stress, and fibrosis under HG condition. Dapagliflozin suppressed HG-induced proliferation, oxidative stress, and fibrosis by reducing Mettl3-induced m6A modification in Marcks mRNA.