SIRT1 and fatty liver disease: Hepatocyte-derived miR-34a has emerged as a potent regulator of steatohepatitis progression via repressing SIRT1 gene that acts as a regulator of energy metabolism within hepatocytes by controlling of AMP kinase activity, hence repressing of SIRT1 gene may result in decreasing hepatocyte metabolism, increasing fat oxidation, progression of hepatic steatosis, and finally cell death [42,46].