Histologic and Metabolic Derangement in High-Fat, High-Fructose, and Combination Diet Animal Models

BACKGROUND We used high-fat (HF), high-fructose (HFr), and combination diets to create a dietary animal model of nonalcoholic fatty liver disease (NAFLD). Comparison of both clinical phenotypes has not been well defined. The purpose of this study was to compare histologic and metabolic characteristics between diets in an animal model of NAFLD. METHODS NAFLD was induced in rats by feeding them HF, HFr, and combination (HF + HFr) diets for 20 weeks. The degree of intrahepatic fat accumulation, inflammation, and oxidative stress was evaluated. Metabolic derangements were assessed by the oral glucose tolerance test and the intrahepatic insulin signal pathway. RESULTS Body weight gain and intrahepatic fat accumulation were more prominent in the HF feeding group than in the HFr group. The expressions of NOX-4 and TLR-4 were higher in the HF and HFr combination groups than in the HF-only group. Other intrahepatic inflammatory markers, MCP-1, TNF-α, and endoplasmic reticulum stress markers, were the highest in the HF + HFr combination group. Although intrahepatic fat deposition was less prominent in the HFr diet model, intrahepatic inflammation was noted. CONCLUSIONS Intrahepatic inflammation and metabolic derangements were more prominent in the HF and HFr combination model than in the HF monodiet model.