Abstract:

Objective       To observe the effect of metformin on myocardial fibrosis in diabetic rats. Methods       Male SD rats were randomly divided into 3 groups: the normal control group(NC group), the diabetes group(DM group), and the diabetes with metformin treatment group(MET group). After SD rats were fed a highfat diet for four weeks, low-doses of streptozotocin(STZ) were intraperitoneally injected to establish the model of diabetes .Then, the DM group and MET group rats were fed the high-fat diet and metformin( ig, 500mg/(kg·d)) was given to the MET group for another 6 weeks . After the last administration, the ratio of heart to body weight (HW / BW) was measured, while myocardial collagen content was quantified through Masson-staining and expressions of TGF-β1 and TSP-1 were detected  by immunohistochemical staining. Results       Compared with the NC group, the HW / BW and myocardial collagen contents were significantly increased  in the DM group and MET group(P<0.05), while expressions of TGF-β1 and TSP-1 were also markedly increased in  both groups(P<0.05). Compared with the DM group, the HW / BW, myocardial collagen contents and expressions of TGF-β1 and TSP-1 were significantly reduced in the MET group. Conclusion       Metformin shows the effect of anti- myocardium fibrosis in diabetic rats.

Key words: Metformin; Diabetes; Modle, animal; Myocardial fibrosis; Transforming growth factor-β1; Thrombospond-1