Non-alcoholic fatty liver disease: an epigenetic view of pathogenesis and a new treatment options

Nonalcoholic fatty liver disease (NAFLD) is the most common reason of chronic liver disease. NAFLD causes a wide array of liver conditions ranging from simple steatosis - to nonalcoholic steatohepatitis (NASH) and advanced hepatic fibrosis. Numerous studies show that epigenetic processes are also involved in the pathogenesis of NAFLD. Shifts in the regularity of genomic DNA methylation can cause aberrant gene expression in NAFLD. Pathogenesis of NAFLD is not entirely understood, but it is well-known that obesity, diabetes and metabolic abnormalities played a significant role in the disease development and progression. Epigenetics is known as an inheritable phenomenon which influences the expression of gene without altering the DNA sequence, offers a new view on the pathogenesis of NAFLD. Moreover, epigenetic mechanisms including DNA methylation, posttranslational histone modifications and non-coding RNAs seem to orchestrate various aspects of NAFLD. Histone acetylation affects gene expression profiles in NAFLD. Abnormal histone changes induce insulin resistance, progression of type 2 diabetes mellitus, and subsequent development of NAFLD. This review reflects new advances in the study of epigenetic mechanisms for the development of NAFLD and the formation of innovative therapeutic targets and the long-awaited diagnostic and prognostic tools based on them.

nonalcoholic fatty liver disease (NAFLD), epigenetics, DNA methylation, liver, steatosis, histone modifications, non-coding RNAs

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