A study was conducted to investigate effects of oral supplementation with
branched-chain amino acids (BCAA) on
protein-nutritional status in rats with
liver cirrhosis.
Liver cirrhosis was induced in male strain Sprague-Dawley rats by simultaneously administrating
carbon tetrachloride (500 mg/kg, twice a week, intracutaneously) and
phenobarbital (0.05% in
drinking water, ad libitum) for 30 weeks. Following treatment with
carbon tetrachloride and
phenobarbital, cirrhotic rats received oral supplementation of BCAA with varying ratio among
isoleucine (Ile),
leucine (Leu) and
valine (Val), or with varying content of total BCAA in the diet (Final content of total
nitrogen was kept consistent by addition of
glutamine). Nutritional efficacies of diets as described above were evaluated employing those
protein-nutritional parameters as
nitrogen balance and plasma levels of total
protein,
albumin and free
neutral amino acids. Following results were obtained: 1. Compositional ratio of Ile:Leu:Val at 1:2:1.2 or at 2:1:1 was found to be more effective on diets which contained ILe:Leu:Val at 1:1:2 or either Val, Ile or Leu alone. 2. As to content of total BCAA in the diet (0, 2.5, 5, 10%), supplementation level of 2.5% was found to be most appropriate in terms of effects on
nitrogen balance and on
plasma protein concentration. In conclusion, 2.5% BCAA in the diet with the ratio of Ile:Leu:Val at 1:2:1.2 or 2:1:1 seems to be recommended to improve the impaired
protein-nutritional status in
liver cirrhosis.