Upregulation of Nrf2 expression in non-alcoholic fatty liver and steatohepatitis

摘要

Background/Aims: The purpose of this study was to examine the expression of Nrf2 in the non-alcoholic fatty liver (NAFL) and steatohepatitis (NASH) in mice. Methodology: Mice were fed a high-fat diet for 8 or 12 weeks before the serum levels of 8-iso-prostaglandin F2α (F2-isoPG) were measured by ELISA; Liver Nrf2 expression was detected by immunohistochemistry. Results: Liver index, serum alanine aminotransferase (ALT), cholesterol (CHOL) and glucose (GLU) increased significantly (p<0.01) in the high fat diet group. The level of F2-isoPG was also statistically higher in the high fat diet group at both 8 and 12 weeks (p<0.05). Nrf2 expression showed robust upregula-tion in both the NAFL and NASH groups as compared to the control group (p<0.05). There was a statistically significant (p<0.05) difference in the overexpression of Nrf2 in the NASH group as compared to the NAFL group. Pearson correlation analysis showed a strong correlation between Nrf2 expression and the degree of hepatic steatosis and inflammation. Conclusions: Our results showed that during the development of NAFL and NASH, F2-isoPG levels increased and Nrf2 expression was upregulated. Our findings suggest Nrf2 may play a key role during liver steatosis, and activation of Nrf2 may protect liver from inflammation damage induced by oxidative stress.