Serum aminotransferases in nonalcoholic fatty liver disease are a signature of liver metabolic perturbations at the amino acid and Krebs cycle level.

In the context of an abnormal hepatic triglyceride accumulation, circulating aminotransferases rise as a consequence of the need for increased reactions of transamination to cope with the liver metabolic derangement that is associated with greater gluconeogenesis and insulin resistance. Hence, to maintain homeostasis, the liver upregulates these enzymes, leading to changes in the amounts of amino acids released into the circulation.