Effects of ketoacids on liver glutathione and microsomal enzymes in malnourished rats

The progression of chronic renal failure is delayed by the use of low protein diets, but such diets are deficient in essential amino acids. In order to maintain good nutritional status, branched-chain ketoacids (BCKA) can be added to these diets. The effects of BCKA on protein metabolism in skeletal muscle is well established, but there is little information about their effects on liver metabolism. Protein deprivation affects some aspects of liver function such as drug metabolism (glutathione, cytochrome P-450 and enzymes). In a chronic protein malnutrition model, we have tested the efficacy of BCKA to correct these abnormalities when they are added to a low protein diet. RNA/DNA, liver proteins, microsomal proteins and glutathione were markedly improved; cytochrome P-450 was only partly improved, and aminopyrine demethylase was not affected. In conclusion, this study suggests that BCKA have a beneficial effect and may prevent the deterioration in the nutritional state of the liver in uremic patients.