Antioxidant Effect Of Selenium-enriched Earthworm On Chronic Liver Fibrosis Mice Induced By CCl₄

Objective: Study of selenium-enriched earthworm suspension on CCl4 induced liver fibrosis in mice liver tissue oxidative index and the effect of Nrf2/ARE signal pathway,To provide experimental basis for clinical prevention and treatment of liver fibrosis.Methods:A mouse model of hepatic fibrosis was established by subcutaneous injection of CCl4 solution,60 male mice were randomly divided into 4 groups: Blank control group(group A),Liver fibrosis model group(group B),Common earthworm group(group C),SE earthworm group(group D),n=15.Mice in group B,C and D were given subcutaneous injection of 15%CCl4 solution 1 times every 3 days for a period of 60 d.SE earthworm group fed selenium-enriched earthworm suspension,Common earthworm group were fed with ordinary earthworm.Earthworm suspension concentration was 0.02 g/ml.The model group and the control group were fed with the corresponding volume of normal saline,a total of 90 d.The blood samples were collected and the liver tissues were harvested under chloral hydrate anesthesia.Whole blood selenium concentration was determined by atomic fluorescence spectrometry;HE staining and Masson staining were used to observe the degree of liver fibrosis;Hepatic hydroxyproline(HYP)by acid hydrolysis,Malondialdehyde(MDA)content by TBA,Superoxide dismutase(SOD)by hydroxylamine assay,Glutathione peroxidase(GSH-Px)by colorimetric detection;Immunohistochemistry and Western Blot assay were used to detect the distribution and expression of Nrf2 protein in liver tissue.Results : Comparison of model group and blank control group: There was no significant difference in selenium concentration in whole blood(P ? 0.05);The pathological damage of the liver structure was serious,the collagen fibers proliferated obviously,and a large number of fat vacuoles formed;HYP,MDA,SOD,GSH-Px,Nrf2 protein were significantly increased in liver tissue(P ? 0.05).Comparison of drug intervention group and liver fibrosis model group:No significant difference between the ordinary earthworm group whole blood selenium concentration(P?0.05),SE earthworm group whole blood selenium concentration increased significantly(P?0.05);The pathological damage of liver was mild,the proliferation of collagen fibers was decreased,and the fat vacuoles were decreased;The contents of HYP and MDA in liver tissue were decreased in different degree(P ? 0.05),and the contents of SOD,GSH-Px and Nrf2 protein were increased(P?0.05).Comparison of SE earthworm group and Common earthworm group:Whole blood selenium concentration increased significantly(P?0.05);The pathological damage of liver structure was lighter,and the collagen fiber and fat vacuoles were decreased;The contents of HYP and MDA in liver tissue were significantly decreased(P?0.05),and the contents of SOD,GSH-Px and Nrf2 protein were significantly increased(P?0.05).Conclusion: The role of selenium-enriched earthworm effective prevention and treatment of liver fibrosis,The mechanism may be related to the promotion of Nrf2 nuclear translocation and activation of the Nrf2/ARE antioxidant pathway in the liver,which may result in the increase of downstream antioxidant factors such as SOD,GSH-Px and so on.