NOS2 and Hepatic fibrosis: Analysis of liver fibrosis from liver samples subject to Masson’s trichrome staining using the Brunt classification revealed that the histological scores and the liver collagen content (which represent liver fibrosis) were significantly higher in iNOS−/−/HFD mice compared with iNOS+/+/HFD mice after 48 weeks of HFD feed (Table 2, Figure 2C and D).