出版社：American Society for Biochemistry and Molecular Biology
摘要：Hepatic steatosis is commonly present during the developmentof insulin resistance, and it is a clear sign of lipotoxicityattributable in part to an accelerated lipogenesis. There isevidence that a soy protein diet prevents the overexpressionof hepatic sterol-regulatory element binding protein-1 (SREBP-1),decreasing lipid accumulation. Therefore, the aim of the presentwork was to study whether a soy protein diet may prevent thedevelopment of fatty liver through the regulation of transcriptionfactors involved in lipid metabolism in hyperinsulinemic andhyperleptinemic Zucker obese fa/fa rats. Serum and hepatic cholesteroland triglyceride levels, as well as VLDL-triglyceride and LDL-cholesterol,were significantly lower in rats fed soy protein than in ratsfed a casein diet for 160 days. The reduction in hepatic cholesterolwas associated with a low expression of liver X receptor- andits target genes, 7- hydroxylase and ABCA1. Soy protein alsodecreased the expression of SREBP-1 and several of its targetgenes, FAS, stearoyl-CoA desaturase-1, and 5 and 6 desaturases,decreasing lipogenesis even in the presence of hyperinsulinemia.Reduction in SREBP-1 was not associated with the presence ofsoy isoflavones.
Finally, soy protein reduced SREBP-1 expression in adipocytes,preventing hypertrophy, which also helps prevent the developmentof hepatic lipotoxicity.Supplementary key words steatosis • liver • liver X receptor- • sterol-regulatory element binding protein-1
and its target genes, 7-
5 and 
