Protective effect of captopril on cardiac fibrosis in diabetic albino rats: a histological and immunohistochemical study

Abstract

Background Cardiomyopathy is one of the common complications of diabetes mellitus.Aim The aim of the present study was to investigate the effects of Captopril on myocardial fibrosis in streptozotocin-induced diabetic rats (an animal model of type 1 diabetes mellitus).Materials and methods Forty albino rats were divided into five groups. Group I (control group), group II (untreated diabetic rats), group III (insulin-treated diabetic rats), group IV (Captopril-treated diabetic rats), and group V (insulin and Captopril-treated diabetic rats) were killed at 4 and 8 weeks, and the samples were collected for histological evaluation using hematoxylin and eosin, Masson trichrome, and immunohistochemical staining with anti-P53 for apoptosis, alpha smooth muscle actin (α-SMA) for collagen deposition.Results Treatment of streptozotocin-induced diabetic rats with insulin and Captopril (group V) showed marked decrease in myocardial injury and apoptosis, which was confirmed by marked decrease of sarcoplasmic p53 expression. Group V also showed decreased collagen deposition as confirmed by Masson trichrome staining and α-SMA expression. The results were better after 8 weeks compared with those after 4 weeks.Conclusion The administration of Captopril alone with diabetic rats minimally affected cardiac fibrosis, while the combination of Captopril and insulin markedly improved cardiac fibrosis.