Protective effect of Genistein against nonalcoholic fatty liver disease in ovariectomized mice and its mechanism / 临床肝胆病杂志

ABSTRACT

ObjectiveTo investigate the protective effect of Genistein against nonalcoholic fatty liver disease （NAFLD） in ovariectomized （OVX） mice and its mechanism. MethodsA total of 40 female C57BL/6 mice， aged 6 weeks， were used to establish an OVX mouse model， and then they were randomly divided into blank group， 4-week model group， 6-week model group， 8-week model group， and 10-week model group， with 8 mice in each group. Under the same environmental conditions， the mice were given high-fat diet for modeling， and pathological examination showed that NAFLD was successfully induced by 10-week high-fat diet. Another 40 female C57BL/6 mice， aged 6 weeks， were randomly divided into blank group， sham operation group （Sham group）， OVX group， OVX+L-Genistein （4 mg/kg body weight） group， and OVX+H-Genistein （8 mg/kg body weight） group. The mice in the Sham group were given the same procedure of OVX， without the ligation of the ovarian artery and the resection of the ovary. The mice in the blank group were given normal diet， and those in the other groups were given high-fat diet. Genistein was dissolved in DMSO， and the mice in the Sham group and the OVX group were treated with solvent solution alone by gavage， once a day for 10 consecutive weeks. Body weight and visceral index were recorded， and the mice were sacrificed to collect serum and liver tissue. Kits were used to measure the activity of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） and the serum levels of triglyceride （TG） and total cholesterol （TC）， and HE staining and oil red O staining were used to observe liver histopathology； Western blot was used to measure the protein expression levels of sterol regulatory element-binding protein 1c （SREBP-1c） and peroxisome proliferator-activated receptor alpha （PPARα） associated with lipid metabolism in liver tissue. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the Dunnett-t test was used for further comparison between two groups. ResultsAfter 10 weeks of high-fat diet， the OVX+L-Genistein group and the OVX+H-Genistein group had significantly lower body weight， liver index， and liver tissue weight （all P<0.05）. In addition， Genistein significantly downregulated the serum levels of TC and TG （P<0.05） and reduced the activities of serum AST and ALT （P<0.05）. HE and oil red O staining showed that compared with the OVX group， the OVX+L-Genistein group and the OVX+H-Genistein group had a significant reduction in the accumulation of lipid droplets. Western blot showed that after Genistein intervention， there was a significant reduction in the protein expression level of SREBP-1c and a significant increase in the protein expression level of PPARα （P<0.05）. ConclusionGenistein exerts a protective effect against NAFLD in OVX mice possibly by regulating the expression of SREBP-1c and PPARα， thereby promoting fatty acid oxidation and inhibiting liver lipid synthesis.