Fig. 1

Changes in histological findings and NAFLD activity scores over time in the NAFLD group and control. Hematoxylin and eosin stained sections of samples from the NAFLD group (× 200) revealed that hepatocyte ballooning and lobular inflammation with lymphocyte infiltration appeared in the perivenular region (zone 3) at 12 weeks and became diffuse at 36 weeks. Microvesicular steatosis also appeared at 36 weeks. Masson trichrome staining (× 20) revealed slight fibrosis in zone 3 at 12 weeks; pericellular fibrosis, at 36 weeks; and complete bridging fibrosis, at 60 weeks. In the control animal, lobular inflammation was observed at 24 and 36 weeks. Fibrosis appeared in zone 3 at 24 weeks, and cirrhosis developed at 36 weeks. NAFLD activity scores in the NAFLD group are expressed as mean values. The NAFLD group; HFD feeding with DEN injection. The control; normal diet feeding without DEN injection