<i>Globimetula braunii</i> prevents hyperglycemia, oxidative damage, and hepatorenal dysfunction in dexamethasone-induced insulin-resistant rats

Introduction: Globimetula braunii is a parasitic plant used in Cameroon in traditional medicine to treat diabetes mellitus. The present work aimed to evaluate the protective effects of aqueous leaf extract of G. braunii (EGB) on rats rendered insulin-resistant by dexamethasone. Methods: To induce insulin resistance, male rats received a subcutaneous dexamethasone injection (1 mg/kg) daily for 10 days. One hour before the administration of dexamethasone, the animals received vehicle, metformin (40 mg/kg), or EGB (120, 240, and 480 mg/kg). Body weight, glycemia, insulinemia, homeostatic model assessment for insulin resistance (HOMA-IR), markers of kidney and liver functions, and oxidative profile were assessed. Results: EGB (240 and 480 mg/kg) caused a significant decrease (P&lt;0.001) in body weight on day 10, hyperglycemia, insulinemia, insulin resistance, and a notable increase (P&lt;0.001) in the transaminases activities, as well as uric acid and creatinine levels. Additionally, EGB at all doses caused a significant increase (P&lt;0.001) in reduced glutathione level and glutathione peroxidase activity in the liver and in superoxide dismutase and catalase activities in the kidneys of the rats. Malondialdehyde levels were significantly decreased in the kidneys of EGB-treated animals at doses of 240 and 480 mg/kg. EGB (240 and 480 mg/kg) also reversed kidney and liver damage caused by hyperglycemia. Conclusion: EGB has remarkable hypoglycemic, hepatoprotective, and nephroprotective properties and protects organs against damage caused by oxidative stress, thus validating the ethnopharmacological use of this plant in the management of diabetes mellitus and some of its comorbidities.