Abstract: Objective To investigate the effects of Fibroblast growth factor 21 (FGF21) siRNA on cardiac function in type 1 diabetic (T1DM) mice and explore the mechanisms of actions. Methods Sixteen C57BL/6J mice were randomly divided into, control group and FGF21siRNA control group, sixteen T1DM model mice were divided into T1DM group and T1DM + FGF21siRNA group, type 1 diabetes was induced by STZ. Cardiac function was analyzed by echocardiography, morphological changes of cardiomyocytes were observed by HE staining, collagen fiber was observed by Masson staining, the expression of α-myocin heavy chain (α-MHC), β-myocin heavy chain (β-MHC), atrial natriuretic peptide (ANP), type I collagen (Col I) and type III collagen (Col III) of myocardium were detected by Real-time PCR. Results The expression of α-MHC, β-MHC, ANP, Col I and Col III in myocardium of T1DM mice treated with FGF21siRNA were increased compared to those of untreated ones. Cardiac function, cardiomyocyte hypertrophy and collagen fiber proliferation of treated mice were worse than those of untreated ones. Conclusion FGF21siRNA may contribute to cardiac malfunction T1DM mice, which may associate with the development of myocardial hypertrophy, myocardial fibrosis.

Key words: FGF21siRNA, Type 1 diabetic (T1DM), Diabetic cardiomyopathy, Myocardial hypertrophy, Myocardial fibrosis