Branched-chain amino acids in liver diseases

Abstract

Branched chain amino acids (BCAAs) have been shown to affect gene expression, protein metabolism, apoptosis and regeneration of hepatocytes, and insulin resistance. They have also been shown to inhibit the proliferation of liver cancer cells in vitro, and are essential for lymphocyte proliferation and dendritic cell maturation. In patients with advanced chronic liver disease, BCAA concentrations are low, whereas the concentrations of aromatic amino acids such as phenylalanine and tyrosine are high, conditions that may be closely associated with hepatic encephalopathy and the prognosis of these patients. Based on these basic observations, patients with advanced chronic liver disease have been treated clinically with BCAA-rich medicines, with positive effects.

Keywords: Liver disease; Branched chain amino acids; Gene expression; Hepatocyte apoptosis; Hepatocyte regeneration; Immunity; Treatment

Core tip: Advanced liver diseases are commonly accompanied by nutritional disturbances, which worsen the prognosis of the patients. Serum levels of branched-chain amino acids (BCAAs) are decreased in patients with liver cirrhosis, and the amino acids imbalance could affect the clinical picture of the disease and the prognosis of the patients. However, there are few comprehensive reviews on the biological activities of BCAAs. In this review, we summarize the biological activities of BCAAs, and discuss possible applications of BCAAs for the management of patients with advanced liver diseases with a list of clinical trials of BCAA administration.