Novel non‐alcoholic steatohepatitis model with histopathological and insulin‐resistant features

Although several non‐alcoholic steatohepatitis (NASH) models have been reported to date, few of these models fully reflect the histopathology and pathophysiology of human NASH. The aim of this study was to establish a novel NASH model by feeding a high‐fat (HF) diet and administering both carbon tetrachloride (CCl₄) and the Liver X receptor agonist T0901317. Male C57BL/6J mice were divided into four groups (each n = 5): HF, HF + CCl₄, HF + T0901317, and the novel NASH model (HF + CCl₄ + T0901317). CCl₄ (0.1 mL/kg) and T0901317 (2.5 mg/kg) were intraperitoneally administered four times and five times, respectively. The livers of the novel NASH model group presented a whitish colour. The serum levels of TNF‐α and IL‐6 were significantly increased in the novel NASH model group, and mice in this group exhibited histopathological features and insulin resistance reflective of NASH, i.e., macrovesicular hepatic steatosis, ballooning hepatocytes, Mallory‐Denk bodies, lobular inflammation and fibrosis. The novel NASH model group presented significantly upregulated expression levels of mRNAs related to lipogenesis, oxidative stress, fibrosis and steatosis and significantly downregulated expression levels of mRNAs related to triglyceride export. We successfully established a novel experimental NASH model that exhibits similar histopathology and pathophysiology to human NASH.