Nutritional and clinical evaluation of a modified soy protein with covalently bound branched-chain amino acids in cirrhotic Sprague-Dawley rats

Several studies suggested that branched-chain amino acids (BCAA) improve plasma amino acid imbalance as well as protein metabolism in patients with cirrhosis. However, commercial formulas supplemented with free BCAA have their limitations. We evaluated a modified soy protein diet with covalently bound BCAA (diet M) by comparing it with diets based on casein (diet C) or Hepatic Aid II (diet H; commercial formula) as protein sources. After 3 weeks of bile duct obstruction, 24 Sprague-Dawley rats divided into three groups received diets with 9% (w/w) protein/amino acids for 7 days. Nutritional and clinical parameters were determined. Nitrogen balance and weight gain (g)/protein intake (g) with diet M (0.19 ± 0.31 and 1.33 ± 1.43 g, respectively) were significantly higher (p<0.05) than with diet H (-0.34 ± 0.20 and -0.34 ± 1.11 g), but comparable to those with diet C (0.04 ± 0.38 and 0.20 ± 0.93 g). Animals on diet M had a significantly (p<0.05) increased plasma BCAA:aromatic amino acid ratio (1.8 ± 0.3) as compared with those on diets H (1.3 ± 0.1) and C (0.8 ± 0.0). There were no significant differences in organ weight or liver function among the groups. We conclude that the BCAA-modified protein is an attractive option in the nutritional support of patients having cirrhosis.