Effects Of Spironolactone On The PTEN Expression In Myocardium Of Type2Diabetic Rats

Objective: To explore the mechanisms of spironolactone on diabetic cardiomyopathy by observing theeffects of spironolactone on the PTEN expression in myocardial tissues of type2diabetic rats.Methods: Eighty healthy male Sprague-Dawley (SD) rats were divided randomly into2groups: Thenormal control rats (group NC, n=12) were fed with routin animal feeds and the model of T2DM rats(n=68) were fed with high-sucrose-high-fat diet for8weeks and then injected low dose Streptozotocin(STZ) by30mg/kg. The diabetic rats were divided randomly into two subgroups: diabetes mellitus controlgroup (group DM, n=11) and diabetic rats treated with Spironolactone (group DS, n=12). The group DMand DS rats were fed with the high-fat-high-sucrose diet. The DS rats were treated with spironolactone40mg/(kg.d) via intragastric administration while group DM and group NC were treated withcorresponding distilled water for8weeks. Body weight and peripheral blood glucose of each group weretested every two weeks. The levels of total cholesterol (TC), triglyceride (TG), fasting blood glucose(FBG), glycosylated hemoglobin (GHbA1c), Kalium（K+）were tested at the end of the experiment. Bodyweight and serum markers were collected8weeks later, in which immunohistochemistry method wasadopted to detect the protein expression of PTEN, p-Ak（tSer473）, real-time quantitative PCR was used todetect the mRNA expression of PTEN in myocardial tissue.Results: TC, TG, FBG, GHbA1c levels in group DM and group DS were higher than those in group NC(P<0.01) and there was no significant difference between group DM and group DS, Kalium levels in thethree groups showed no significant difference（P>0.05）; the diabetic cardiomyopathy of group DS weresignificantly improved compared with group DM; the PTEN mRNA and protein expression, comparedwith group NC, were significantly lower in group DM (P<0.01) and the one in group DS is higher thanthat in group DM (P<0.05); compared with group NC, the p-Akt (Ser473) protein expression wassignificantly higher in group DM (P<0.01) and the one in group DS is lower than that in group DM(P<0.05).Conclusion: Spironolactone may prevent diabetic cardiomyopathy by increasing PTEN and decreasingphosphorylated Akt levels in type2diabetic rats.