Effect of Dalbergiella welwitschi alkaloid-rich leaf extracts on testicular damage in streptozotocin-induced diabetic rats

Diabetes mellitus is a chronic disease affecting young and old, even though it can be managed with orthodox medicine, which has a series of side effects. Therefore, Dalbergiella welwitschi is one of the medicinal plants that is commonly used for the management of diabetes mellitus and its associated complications. Hence, this study was designed to assess the testicular-protective ability of alkaloid-rich leaf extract of D. welwitschi in streptozotocin-induced type 2 diabetic rats D. welwitshii leaf alkaloid-rich extract was obtained using standard procedure. Streptozotocin was injected into the experimental animals intraperitoneally at a dose of 45 mg/kg body weight to induce type 2 diabetes mellitus. Prior to this, the animals were given 20% (w/v) fructose for one week. Thus, the animals were grouped into five (n = 8), comprising of un-induced rats (NC), diabetic control (DC), diabetic rats treated with low (50 mg/kg body weight) and high (100 mg/kg body weight) doses of D. welwitschi alkaloid-rich leaf extracts (i.e., DWL and DWH respectively) and 200 mg/kg body weight dose of metformin (MET). The animals were sacrificed on the 21st day, blood and testis were harvested and used for the determination of ions (Fe, Cu and Zn), sialic acid, some hormones (testosterone, luteinizing and follicle stimulating), oxidative stress biomarkers [malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and glutathione (GSH)] as well as histological examination. In addition, the results show that diabetic rats placed on DWL, and DWH significantly (p < 0.05) decreased ion levels (Fe, Cu and Zn) and ameliorated oxidative stress biomarkers such as MDA, SOD, CAT, GPx, GST, and GSH. These were supported by the histological examination by improving testicular-protective effects in diabetic rats administered DWL, and DWH. Therefore, it is that assume that the alkaloid-rich leaf extracts of D. welwitschi may offer potential benefits in the treatment of diabetic testicular dysfunction.