Impact of Garcinia kola and Kigelia africana Polyherbal Extract on Endothelial Dysfunction and Angiogenesis in Type-2 Diabetic Wistar rats: Regulation of Angiopoeitin-1 and Heme Oxygenase-1

Diabetes mellitus, particularly type-2 diabetes is associated with complications such as increased gluconeogenesis, ketogenesis, advanced glycation end product formation (AGEs), and free radicals that promote the inflammatory process, thereby affecting vascular integrity that eventually leads to endothelial dysfunction. This study aimed to investigate the impact of Garcinia kola and Kigelia africana polyherbal extract on endothelial dysfunction and angiogenesis in Type-2 Diabetic Wistar rats. Forty-two male Wistar rats were divided into six groups of seven rats each, namely; [Diabetic control (DMC)]; normal control [PC], extracts only (EC) [250 mg/kg], synthetic drugs only (SDM) [5 mg/kg glibenclamide + 100 mg/kg metformin], extract low dose (ELD) [250 mg/kg] and extract high dose (EHD) [500 mg/kg]. Diabetes was induced by intraperitoneal injection of 110 mg/kg nicotinamide (NA) followed by 65 mg/kg of streptozocin (STZ). The extracts were administered once daily for six weeks. After the treatment period, blood samples, mesenteric arteries, and kidney tissues were collected and used for biochemical and immunohistochemical analysis, including antioxidant activity, liver function [aspartate aminotransferase (AST) and alanine transaminase (ALT)], renal function (uric acid, urea, and creatinine), nitric oxide (NO), angiopoeitin-1, heme oxygenase-1 (HO-1), as well as indirect bilirubin assays using commercial assay kits following the manufacturers’ protocols. Results showed that administration of polyherbal extract of G. kola and K. africana significantly increased antioxidant enzymes activities, angiopoeitin-1, NO, HO-1, and indirect bilirubin levels. These findings suggest that the polyherbal extract of G. kola and K. africana has the potential to ameliorates endothelia dysfunction in STZ-nicotinamide-induced diabetic Wistar rats.