Antioxidant Potentials of Terminalia catappa Seed Extract and Metformin on the Liver and Kidney of Diabetic Wistar Rats

The antioxidant effects of Terminalia catappa ethanol seed extract in the liver and kidneys of diabetic Wistar rats induced with streptozotocin was investigated. Thirty rats weighing 140 g – 180 g were randomly divided into five treatment groups. The normal control (NC) and 50 mg/kg b.w streptozotocin-induced diabetic control (DC) groups received placebo, while the treated groups included 500 mg/kg b.w metformin only group (G), 500 mg/kg b.w T. catappa seed extract only group (E) and combined 250 mg/kg b.w dose each of Metformin and T. catappa seed extract (GE). Administration was via oral gavage for 21 days. The animals were sacrificed and the effect on antioxidant enzymes and lipid peroxidation in the kidney and liver tissue homogenates were evaluated. The results obtained showed that treatment with T catappa seed extract and metformin significantly (p<0.05) improved glutathione, (GSH) levels in hepatic tissues in the diabetic rats while no significant effect was observed in the kidneys. Further, renal and hepatic levels of glutathione peroxidase and superoxide dismutase showed significant reduction (p<0.05) in the untreated diabetic group, an observation that was reversed following treatment with T. catappa seed extract and reference drug, metformin. Additionally, treatment with T. catappa and metformin was observed to significantly decrease the levels of malondialdehyde (MDA) in both hepatic and renal tissues. Conclusively, T. catappa has antioxidant activities and is a potential candidate to manage diabetes related oxidative stress.