SGLT2 promotes cardiac fibrosis following myocardial infarction and is regulated by miR‑141

Cardiac fibrosis is a primary event during myocardial infarction (MI) progression, which impairs cardiac function. The present study aimed to investigate the effect of SGLT2 on cardiac fibrosis following MI. To validate the role of SGLT2 in the regulation of cardiac fibrosis in vivo, an MI rat model was established. Echocardiography was performed to determine cardiac function at 4 weeks post‑MI. MI model rats were transfected with short hairpin RNA (sh)‑SGLT2 or sh‑negative control lentiviruses to investigate the effect of SGLT2 on rat heart function post‑MI. Subsequently, the effects of SGLT2 on the cardiac fibrosis of infarcted hearts were assessed by performing Masson's trichrome staining. To further clarify the effect of SGLT2 on cardiac fibroblast proliferation, TGFβ was used to stimulate primary cardiac fibroblasts in vitro. The results demonstrated that SGLT2 served a key role in cardiac fibrosis. SGLT2 expression levels in infarct tissues were significantly increased at week 1 post‑MI compared with the sham group. Compared with the control group, SGLT2 knock‑ down attenuated cardiac fibrosis by inhibiting the expression of collagen I and collagen III in cardiac fibroblasts in vitro and in vivo. Furthermore, the results indicated that SGLT2 expres‑ sion was modulated by miR‑141 in cardiac fibroblasts. In summary, the present study indicated that upregulated SGLT2 expression in cardiac fibrosis following MI was regulated by miR‑141 and SGLT2 that knockdown reduced cardiac fibrosis and improved cardiac function after MI.