Time Course of the Development of Nonalcoholic Fatty Liver Disease in the Otsuka Long-Evans Tokushima Fatty Rat

Abstract

Nonalcoholic fatty liver disease (NAFLD) is considered a hepatic manifestation of metabolic syndrome. In this study, we investigated histological and biochemical changes in NAFLD and the gene expression involving de novo lipogenesis in Otsuka Long-Evans Tokushima fatty (OLETF) rats. We used OLETF rats and Long-Evans Tokushima Otsuka (LETO) rats as animal models of NAFLD and as controls, respectively. Consistent observations were made at 4-week intervals up to 50 weeks of age, and all rats were fed ad libitum with standard food. Biochemical and histological changes were observed, and gene expression involved in de novo lipogenesis was measured using real-time polymerase chain reactions. As a results hepatic micro-and macrovesicular steatosis and hepatocyte ballooning were evident in the OLETF rats at 22-38 weeks of age but disappeared after 42 weeks