Fundament and Application
HUANG Meiqi, LIU Yanqun, LIU Zhao, GUO Jiacheng, HUANG Xinyi, ZHANG Ran, LIU Yi, YUE Yuqing, CHANG Yutong, HUANG Wenwu
Objective To understand the protective effect and mechanism of corn peptide(CP) on liver injury in mice exposed to subchronic cadmium(Cd2+). Methods Thirty male C57BL/6J mice were randomly divided into 5 groups,6 mice in each,the blank control group,Cd2+ exposure group,Cd2+ exposure+low-dose CP(400 mg/kg) group,Cd2+ exposure+moderate-dose CP(600 mg/kg) group and Cd2+ exposure+high-dose CP(800 mg/kg) group. The blank group was given an equal volume of normal saline. A subchronic cadmium poisoning model was established in the Cd2+ treated group after 2 mg/kg Cd2+ solution was injected intraperitoneally every other day for 4 weeks. CP group was given CP solution at 400,600 and 800 mg/kg,respectively,once a day for 28 days. At the end of the experiment,the mice were sacrificed to collect blood,take the liver to calculate its organ coefficient,hematoxylin-eosin(HE) staining to observe the liver tissue. Liver homogenate was prepared to detect malondialdehyde(MDA),superoxide dismutase(SOD),catalase(CAT) and glutathione(GSH) levels. The contents of alanine aminotransferase(ALT) and aspartate aminotransferase(AST) in the serum separated by blood centrifugation were detected by automatic biochemical analyzer. Analysis of variance and LSD test were performed using SPSS 24.0. Results Compared with the control group,the body weight of mice in Cd2+-exposed group decreased,the liver organ coefficient increased,the liver MDA level increased,the SOD,CAT,GSH levels decreased,and the serum ALT and AST levels increased. Compared with the Cd2+ exposed group,the body weight of CP group increased,MDA level in liver decreased,SOD,CAT and GSH levels increased,with significant differences(P<0.05),ALT and AST levels decreased,and there was a significant difference between the CP high-dose group and the model group in ALT level(P<0.05). Conclusion CP has a protective effect on the liver of subchronic cadmium exposed mice,and the reduction of oxidative stress in the liver may be involved in the mechanism of CP protection.