Differences in metabolic and liver pathobiology induced by two dietary mouse models of nonalcoholic fatty liver disease

Abstract

ABSTRACTNon-alcoholic fatty liver disease (NAFLD) is a growing epidemic associated with key aspects of metabolic disease such as obesity and diabetes. The first stage of NAFLD is characterized by lipid accumulation in hepatocytes, but this can further progress into non-alcoholic steatohepatitis (NASH), fibrosis or cirrhosis, and hepatocellular carcinoma (HCC). A western diet, high in fats, sugars and cholesterol is linked to NAFLD development. Murine models are often used to experimentally study NAFLD, as they can display similar histopathological features as humans; however, there remains debate on which diet-induced model most appropriately and consistently mimics both human disease progression and pathogenesis. In this study, we performed a side-byside comparison of two popular diet models of murine NAFLD/NASH and associated HCC: a high fat diet supplemented with 30% fructose water (HFHF) and a western diet high in cholesterol (WDHC), comparing them to a common grain-based chow diet (GBD). Mice on both experimental diets developed liver steatosis, while WDHC-fed mice had greater levels of hepatic inflammation and fibrosis than HFHF-fed mice. In contrast, HFHF-fed mice were more obese and developed more severe metabolic syndrome, with less pronounced liver disease. Despite these differences, WDHC-fed and HFHF-fed mice had similar tumour burdens in a model of diet-potentiated liver cancer. Response to diet and resulting phenotypes were generally similar between sexes, albeit delayed in females. Notably, although metabolic and liver disease phenotypes are often thought to progress in parallel, this study shows that modest differences in diet can significantly uncouple glucose homeostasis and liver damage. In conclusion, long-term feeding of either HFHF or WDHC are reliable methods to induce NASH and diet-potentiated liver cancer in mice of both sexes; however, the choice of diet involves a trade-off between severity of metabolic syndrome and liver damage.Competing Interest StatementThe western diet high in cholesterol (WDHC) was provided by ResearchDiets. Data was discussed with staff at ResearchDiets prior to publication; however, they were not involved in experimental design, data analysis, data interpretation or writing of the manuscript.View Full Text