Branched-chain amino acid-enriched diet: effects on insulin secretion and cellular immune aggression.
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.
Karabatas
L M
LM
Centro de Investigaciones Endocrinol¿ogicas, Hospital de Ninos Ricardo Gutierrez, Buenos Aires, Argentina.
De Bruno
L F
LF
Pastorale
C
C
Lombardo
Y B
YB
Basabe
J C
JC
D000597:Amino Acids, Branched-Chain / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D018920:Coculture Techniques; D003921:Diabetes Mellitus, Experimental / Q000276:immunology*; D019587:Dietary Supplements; D005947:Glucose / Q000494:pharmacology; D007111:Immunity, Cellular / Q000187:drug effects; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D017710:Lymphocyte Transfusion; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D013154:Spleen / Q000276:immunology*; D014185:Transplantation, Isogeneic / Q000276:immunology / Q000502:physiology
D000597:Amino Acids, Branched-Chain; D007328:Insulin; D005947:Glucose