Effects of local curcumin on oxidative stress and total antioxidant capacity in vivo study

Plants have been one of the important sources of medicine even since the-dawn of human civilization. Curcumin has been found to possess tremendous therapeutic potency as antiinflammatory, antioxidant and antimicrobial agent. The present study was designed to examine possible potential therapeutic and protective effect of curcumin from oxidative stress and on total antioxidant capacity in liver damage. The study was conducted using H2O2 as inducing agent of oxidative stress in vivo. Rats were randomly divided into five groups, where n = 20 for each group. Group 1 (G1) rats served as control group. Group 2 (G2) rats subjected to experimentally induced oxidative stress by the ad libitum supply of drinking water containing 0.5% H2O2(v/v) was prepared daily over entire 60 days. Group 3 (G3) rats received H2O2 for sixty days followed by giving 200 mg kg(-1) of curcumin for 30 days. Group 4 (G4) was simultaneously given curcumin (200 mg kg(-1)) for 15 days then followed by receiving H2O2 with curcumin for sixty days. Group 5 (G5) rats was received H2O2 for sixty days followed by giving 200 mg kg(-1) of N-acetyl 1-cystine as standard drug for 30 days. Levels of marker enzymes (ALT, AST and ALP), uric acid, Total Protein (TP) and tumor necrosis factor (α-TNF) were assessed in serum for all studied groups. Malondialdehyde (MDA), 8-hydroxy-2-deoxyguinosine, Total Antioxidant Capacity (TAC), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) were assayed in liver homogenates for all studied groups. The results revealed significant increase (p < 0.05) in levels of ALT, AST, ALP, uric acid and α-TNF while there are significant decrease (p < 0.05) in levels of TP in G2 comparing to G1. Also there are significant differences (p < 0.05) between G3 and G4 comparing to G2 and between G3, G4 and G5 which curcumin elicited a significant hepatoprotective activity by lowering the levels of serum marker enzymes and lipid peroxidation. The results also revealed a significant increase (p < 0.05) in levels of MDA and 8-H-2-deoxy guinosine while there was significant reduction (p < 0.05) in TAC, GSH, SOD and catalase in G2 comparing to G1. Also there are significant differences (p < 0.05) between G3 and G4 comparing to G2 and between G3, G4 and G5. The conclusion could be drown from this study that the ability of curcumin as therapeutic agent and hepatoprotective against liver damage from oxidative damage and on TAC more than N-acetyl 1-cystine related to its antioxidant and free radical scavenger activity.