[Animal Experiment]-Study on Antioxidant Protective Effect of Ground Turtle Peptide on CC14-induced Chronic Liver Injury in Mice

  Objective   To investigate the anti-oxidant protective effect of Dionysian peptides on mice with chronic liver injury induced by CC14.

  Methods Mice were randomly divided into normal group, model group, ground turtle peptide group (50, 100, 200 mg/kg) and positive drug group. Normal group mice were given normal saline, and ground turtle peptide group mice were given different doses of ground turtle peptide every day The mice in the positive drug group were given silymarin (100mg/kg) daily for 6 weeks. At the same time, except for the mice in the normal group, the mice in the other groups were injected intraperitoneally with 0.1% CC14 peanut oil solution 10ml/kg, 2 times a week for 6 consecutive weeks, 24 hours after the last administration, the mice were weighed and sacrificed to take liver tissues. The liver histological changes were observed by HE staining. Liver functional enzymes (AST, ALT), antioxidant enzymes (SOD, CAT, GSH-Px), peroxide (MDA), fluorescence quantitative PCR method to determine the gene expression of inflammatory factors, apoptosis factors, and fibrosis factors, and ELISA to determine the protein levels of inflammatory factors.

  Results Microscopic observation showed no abnormalities in the liver cells of the normal group. The liver cells of the model group showed congestion, necrosis, fibrosis, and the disappearance of liver lobules. The liver cell morphology and structure of the murine peptide group were damaged. The dose of murine peptide was increased. The degree of cell damage was significantly weakened, and the liver and spleen index of mice was significantly lower than that of the model group. Compared with the model group, the activity of AST and ALT in the serum of mice in the ground turtle peptide group was significantly reduced, the content of MDA in the liver was significantly reduced, and antioxidant enzymes (SOD, CAT) , GSH-Px) activity was significantly increased, inflammatory factors (IL-6, TNF-α, iNOS) protein and gene expression levels were significantly reduced, pro-apoptotic factors (Bax, Caspase-3) and fibrosis factors (α-SMA , TGF-β) gene expression is also significantly reduced.

  Conclusion  The ground turtle peptide can effectively improve the chronic liver damage caused by CC14 in mice, and its protective effect may be closely related to the antioxidant effect of the ground turtle peptide.