Protective Effects of Garcinia kola Stem Barks Aqueous Extract on Metabolic Disorders and Oxidative Stress in Dexamethasone-Induced Insulin Resistance in Rat

Aim: To evaluate how the Garcinia kola stem bark aqueous extract impacted dexamethasone-induced insulin resistance in male rats. Method: This work was completed in 2020. The extract was first subjected to phytochemical analysis. Using acute and subacute studies (11 days), the effect of the extract was evaluated at 200 mg/kg and 400 mg/kg, on dexamethasone-induced hyperglycemic rats. Glycemia was measured before and after treatment in both studies, while histological examination for isolated liver, kidneys, and pancreas was performed. Body weight and some internal organs weights were determined, and biochemical assays, for blood samples were achieved only for the subacute study. Results and Conclusion: The existence of alkaloids, phenolic compounds, flavonoids, saponins, coumarins, anthocyanins, and anthraquinones was discovered in the plant's chemistry. G. kola extract decreased the Area Under Curve induced by dexamethasone injection, in the acute and in the subacute test. The extract and glibenclamide decrease the alanine aminotransferase activity induced by DEXA. In the glibenclamide and extract groups, total protein levels increased. In comparison to control, the uric acid level in dexamethasone-treated rats remains elevated. Rats treated with the extract or glibenclamide exhibited an increase in superoxide dismutase activity. Dexamethasone induced islet hypertrophy in the pancreas, vascular congestion, cytolysis, and vacuolation of hepatocytes. The kidney presented leucocyte infiltration and a decrease in glomerular cell density. All of these abnormalities were remedied by the administration of glibenclamide or Garcinia kola extract.