Introduction: The influences of dietary fatty acids on the progress of chronic liver diseases have attracted lots of attentions, but the mechanisms of the effects of lipids rich in saturated fatty acids or PUFAs on hepatic fibrogenesis remain unclear. Methods: Female Fischer 344 rats were fed normal chow or chow plus 20% (w/w) of corn oil or lard, respectively, and injected CCl4 twice a week for 4 weeks to induce liver fibrosis. Masson's staining was adopted to illustrate the fibrosis level. The mRNA expression level of alpha-SMA and the DNA methylation level of its promoter region were analyz...