AMELIORATIVE EFFECT OF AQUEOUS CURRY LEAF (MURRAYA KOENIGII) EXTRACT AGAINST CADMIUM-INDUCED OXIDATIVE STRESS IN RAT LIVER: INVOLVEMENT OF ANTIOXIDANT MECHANISMS

Objective: The present study was intended to examine whether administration of aqueous extract of the Curry leaves (Murraya koenigii L.) do possess a protective effect against cadmium-induced oxidative stress in rat liver. Methods: Male albino rats used for present studies were divided in to four groups; control, cadmium treated, aqueous extract protected and only aqueous extract treated (positive control). The rats were treated with cadmium chloride subcutaneously every alternate day for a period of fifteen days and the extract was administered orally every day for fifteen days. Results: Cadmium-induced liver damage was clearly evident from increased activities of serum glutamate pyruvate transaminase , alkaline phosphatase, lactate dehydrogenase 5, and total LDH. An increased tissue level of lipid peroxidation, and protein carbonyl as well as decreased reduced glutathione and total-thiol (SH) content along with significant changes in the activities of antioxidant enzymes like superoxide dismutase, catalase, glutathione S transferase and glutathione peroxidase indicate development of oxidative stress due to Cd treatment. Besides, increased activities of the pro-oxidant enzymes, enhanced formation of superoxide and hydroxyl radical further confirms elevated levels of oxidative stress following cadmium treatment. Cadmium treatment also altered the activities of mitochondrial Kreb’s cycle and respiratory chain enzymes. Tissue histomorphological studies also showed considerable damage following cadmium treatment. All these changes were significantly protected when the rats were pre-treated with aqueous Curry leaf extract. Conclusion: The present studies suggest that the aqueous Curry leaf extract may be beneficial in ameliorating cadmium-induced oxidative damage in the liver of rats.