GPT and fatty liver disease: Hepatic steatosis and the early stage of inflammatory changes in the liver have been shown in both of these strains of mice, but the MCD diet is required to increase the serum alanine aminotransferase (ALT) levels and develop prominent steatosis in zone 3 (pericentral) and the subsequent necroinflammation which are similar to what occurs in human NASH [22, 23].