Branched-chain amino acid-enriched diet: effects on insulin secretion and cellular immune aggression

Proc Soc Exp Biol Med. 2000 Jul;224(3):159-65. doi: 10.1046/j.1525-1373.2000.22415.x.

Abstract

Several reports have demonstrated that high-protein diets may have beneficial effects on experimental models of diabetes and have raised the possibility that branched-chain amino acids could play a role in these protective effects. We investigated the effect of a normoproteic, branched-chain amino acid-enriched diet (experimental diet) on insulin secretion from C57BL/6N mice transferred with splenocytes from diabetic syngeneic donors. Mice previously fed with the experimental or control diet received three intraperitoneal injections, every other day, of 5 x 107 viable mononuclear splenocytes obtained from control or diabetic donors. Results showed that mice fed with the experimental diet and transferred with "diabetic" splenocytes presented: i) normoglycemia, and (ii) significantly higher levels in both phases of glucose-induced insulin secretion and normal values of arginine-glucose-induced insulin secretion. To evaluate the in vitro cellular immune aggression, dispersed mouse islet cells were co-cultured with splenocytes from syngeneic diabetic mice. First, dispersed islet cells from mice on the experimental or control diet were co-cultured with splenocytes from control or diabetic mice on a commercial diet. In the presence of "diabetic splenocytes, dispersed islet cells from mice on the experimental diet presented a significantly lower in vitro cellular immune aggression. On the other hand, "diabetic" splenocytes from mice fed with the experimental diet produced a significantly reduced cellular immune aggression on dispersed islet cells. Our results showed that feeding branched-chain amino acids increased the capacity of beta cells to withstand a functional assault and diminished the extent of in vitro cellular immune aggression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids, Branched-Chain / pharmacology*
  • Animals
  • Cells, Cultured
  • Coculture Techniques
  • Diabetes Mellitus, Experimental / immunology*
  • Dietary Supplements*
  • Glucose / pharmacology
  • Immunity, Cellular / drug effects
  • Insulin / metabolism*
  • Insulin Secretion
  • Islets of Langerhans / drug effects
  • Islets of Langerhans / immunology
  • Islets of Langerhans / metabolism*
  • Lymphocyte Transfusion*
  • Lymphocytes / immunology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Spleen / immunology*
  • Transplantation, Isogeneic / immunology
  • Transplantation, Isogeneic / physiology

Substances

  • Amino Acids, Branched-Chain
  • Insulin
  • Glucose