Prolonged exposure of C57BL/6j mice to HFD causes NASH [30]. The chronic accumulation of triglycerides in the liver causes oxidative stress and associated inflammation, which leads to considerable liver enlargement. The liver mass held constant in both genders of each of the respective strains between 6 and 11 weeks of the HFD challenge, but increased 2-fold in male and female WT mice between 11 and 36 weeks (Figure 5A). Due to the previously mentioned delay in female DIO responses, the effects on 36 week females were similar to those on 11 week males. These increases were all substantially attenuated by Cyp1b1 deletion. The weights of other organs (heart, spleen and thymus) were not affected either by HFD or by Cyp1b1 deletion (unpublished data).
