Antidiabetic and ameliorative efficacy of two varieties of Psidium guajava L. fruit extracts in type 2 diabetes and indices of complications in diabetic albino rats

Background: Diabetes mellitus (DM) is a chronic metabolic disease which leads to dysfunction in the insulin production/insulin action or both. Hyperglycemia condition in DM results in oxidative stress with decreased antioxidants which leads to various diabetes-related complications. Natural antioxidants are considered to be very effective in preventing hyperglycemia due to the presence of chemical constituents in it. Aims and Objectives: This study aims to investigate the antidiabetic and ameliorative efficacy of two varieties of Psidium guajava L. (PG), namely, Lalit (LA) and Allahabad safeda (AS) in preventing complications in type 2 diabetes in albino rats. Materials and Methods: Matured male albino rats were randomly divided into four groups of six animals (n = 6) each. The first group of rats was served as control. The second group of rats was injected with 45 mg/kg/bw of streptozotocin (STZ) intraperitoneally for the induction of diabetes. The third and fourth groups of STZ-induced rats were supplemented with 200 mg/kg/bw of fruit extract of LA and 400 mg/ kg/bw fruit extract of AS through oral gavage for 8 weeks, respectively. Results: Significant elevation in lipid peroxidation (LPO) levels, reduced activities of superoxide dismutase, catalase, reduced glutathione (GSH), and GSH peroxides (GPx) in pancreas of diabetic-induced albino rats in contrast to controls. However, except the activity of GPx, treatment of 200 mg/kg/bw of LA significantly prevented the above changes. In comparison, the fruit extract of AS (400 mg/kg/bw) could not prevent diabetes-induced alterations in antioxidant enzymes and LPO levels. Conclusion: Our findings clearly indicate, fruit extract of LA of PG is potent enough to prevent oxidative stress in diabetic rats compared to AS. Thus, LA fruit extract could be used as natural antidiabetic in DM.