Repositioning Glibenclamide in cardiac fibrosis by targeting TGF-β1-pSmad2/3-NLRP3 cascade

The proposed objective of this study is to attenuate cardiac fibrosis by inhibiting NLRP3 inflammasome and related genes in uninephrectomized-DOCA fed rat model. Cardiac fibrosis was induced in male Sprague Dawley rats by uninephrectomy and by subsequent administration of deoxycorticosterone acetate (DOCA) every 4th day till 28 days along with 1% NaCl in drinking water. Further, the animals in treatment groups were treated with Glibenclamide (10, 20 and 40 mg/kg) for 28 days which was selected based on docking study. Interim analysis was carried out on the 14th day to assess the hemodynamic parameters. On the 28th day, anthropometric, hemodynamic, biochemical and oxidative stress parameters, gene expression (TGF-β1, pSmad 2/3, NLRP3, IL-1β and MMP-9), ex vivo Langendorff studies and Masson's trichrome staining of heart was carried out. Results were interpreted using ANOVA followed by post hoc Bonferroni test. Glibenclamide treatment significantly reduced the increase in blood pressure. Furthermore, the ECG patterns of the treatment groups displayed a lower frequency of the slow repolarizing events seen in the model animals. Moreover, Glibenclamide treatment demonstrated normal LV function as evidenced by a significant decrease in LVEDP. Besides, this intervention improved the anthropometric parameters and less collagen deposition in Masson's trichrome staining. The cascade of TGF-β1-pSmad2/3-NLRP3 was downregulated along with suppression of IL-1β. Our study repositioned anti-diabetic drug Glibenclamide to treat cardiac fibrosis by inhibiting the TGF-β1-pSmad2/3-NLRP3 cascade.