EFFECTS OF HIGH COPPER DOSE ON MORPHOLOGY AND ANTIOXIDANT FUNCTION OF LIVER AND KIDNEY IN MICE

Objective To study the effects of high dose of copper on morphology and antioxidant function of liver and kidney in mice. Methods Fifty healthy 30 d kunming mice were randomly divided into five groups(n=10): control group. the experimental group Ⅰ, Ⅱ,Ⅲ and Ⅳ. Each group was gavaged with copper sulfate at doses of 0, 20, 50, 100, 100 mg/kg bw, respectively. All mice drank distilled water except group Ⅳ 500 mg/L VC solution was provided. The experiment lasted for 28d and then the mice were killed. Liver and kidney tissue paraffin sections were observed and antioxidant function was determined. Results Compared to the control group, diminished hepatic parenchymal cells and increased cellular gap were observed in copper treatment groups, widening kidney interstitial, damaged glomerular integrity were also observed. The T-AOC, SOD, and GSH-Px activities of liver and kidney tissues increased and MDA content decreased in low dose(20mg/kg) of copper intake group. However the T-AOC activities of SOD and GSH-Px decreased and MDA content increased in higher dose of copper(≥50mg/kg) intake groups. Compared to the VC supplemented group to the same dose of copper intake(group Ⅲ), T-AOC, SOD, GSH-Px activities in liver increased and MDA content decreased. However, the activities of renal antioxdative enzymes did not change significantly and MDA content decreased. Conclusion The redox balance of liver and kidney was disrupted and resulted in significant morphologic changes in liver and kidney after intake of excessive copper. VC supplementation increases antioxidant capacity of liver and kidney and protects them against copper-induced oxidative stress.