Antioxidant Effect of Curcumin Against Microcystin- LR-Induced Renal Oxidative Damage in Balb/c Mice

Purpose: To investigate the effect of curcumin on microcystin-LR (MC-LR)- induced renal oxidative damage in Balb/c mice. Methods: 40 male Balb/c mice were assigned randomly to 4 groups each having 10 mice. One group served as normal (saline treated) while another group was used as curcumin control. The third group was given MC-LR and used as toxin control. The fourth group was pre-treated with curcumin (300 mg/kg body wt) given orally once daily for 14 days before interperitoneal injection (i.p) of MC-LR (75 µg/kg body wt). Biochemical assays including serum creatinine, blood urea nitrogen (BUN), urinary glucose, gamma-glutamyl transferase (GGT) and catalase (CAT) levels were measured. Renal biochemical tests such as protein carbonyl contents and DNA-protein cross-links, glutathione peroxidase (GSH-Px) activity, glutathione (GSH) and lipid hydroperoxide (LOOH) were evaluated. Results: Serum creatinine, BUN, urinary glucose, GGT increased in mice treated with MC-LR, while creatinine clearance decreased compared to controls (p < 0.001), indicating occurrence of tubular damage. There was increased protein carbonyl content and DNA-protein cross-links in the kidney homogenates of these mice. Curcumin administration significantly reversed these effects and attenuated the MC-LR-induced reduction in the activities of CAT, GPH-Px, GSH as well as the MC-LR-induced increases in plasma and kidney lipid hydroperoxide. Conclusion: These results indicate that curcumin possesses natural antioxidant properties that renders it a potent protective agent against renal oxidative damage mediated by microcystin-LR.