Abstract: L-malate, an important organic acid on the process of metabolism, plays an important role in generating mitochondria ATP(adenosine triphosphate). To investigate the effects of L-malate on activities of ALT (alanine aminotransferase) and AST (aspartate aminotransferase) in different tissues of aged rats, Sprague-Dawley male rats were randomly divided into 4 groups, each group consisting of 6 animals. L-malate was orally administrated via intragastric canula for 30 days, then the rats were sacrificed and the liver and heart were removed to determine the activities of ALT and AST. Activities of ALT and AST in liver of aged rats decreased compared with control young rats. The activities of ALT in liver of aged rats were enhance (p<0.05) 41.98% by L-malate administration. Our data indicate that enzyme metabolism of liver in aged rats was strengthened by dietary supplementation with L-malate.

Key words: L-malate, alanine aminotransferase, aspartate aminotransferase, aminotransferase