TY - JOUR

T1 - L-Arginine improves multiple physiological parameters in mice exposed to diet-induced metabolic disturbances

AU - Clemmensen, Christoffer

AU - Madsen, Andreas Nygaard

AU - Smajilovic, Sanela

AU - Holst, Birgitte

AU - Bräuner-Osborne, Hans

N1 - Keywords: L-Arginine; Diet; Amino acids; Low protein; Insulin sensitivity; Obesity; Diabetes

PY - 2012

Y1 - 2012

N2 - L: -Arginine (L: -Arg) is a conditionally essential amino acid and a natural constituent of dietary proteins. Studies in obese rats and type 2 diabetic humans have indicated that dietary supplementation with L: -Arg can diminish gain in white adipose tissue (WAT) and improve insulin sensitivity. However, the effects of L: -Arg on glucose homeostasis, body composition and energy metabolism remain unclear. In addition, no studies have, to our knowledge, examined whether L: -Arg has beneficial effects as a dietary supplement in the mouse model. In the present study, we investigated the effects of L: -Arg supplementation to male C57BL/6 mice on an array of physiological parameters. L: -Arg supplemented mice were maintained on a low-protein diet and body composition, appetite regulation, glucose tolerance, insulin sensitivity and energy expenditure were evaluated. A significant reduction in epididymal WAT was observed in L: -Arg supplemented mice compared with mice fed an isocaloric control diet. Surprisingly, the L: -Arg supplemented animals were hyperphagic corresponding to a highly significant decrease in feed efficiency, as body weight developed in a similar pattern in both experimental groups. Glucose homeostasis experiments revealed a major effect of L: -Arg supplementation on glucose tolerance and insulin sensitivity, interestingly, independent of a parallel regulation in whole-body adiposity. Increased L: -Arg ingestion also raised energy expenditure; however, no concurrent effect on locomotor activity, substrate metabolism or expression of uncoupling proteins (UCP1 and UCP2) in adipose tissues was displayed. In conclusion, dietary L: -Arg supplementation substantially affects an array of metabolic-associated parameters including a reduction in WAT, hyperphagia, improved insulin sensitivity and increased energy expenditure in mice fed a low-protein diet.

AB - L: -Arginine (L: -Arg) is a conditionally essential amino acid and a natural constituent of dietary proteins. Studies in obese rats and type 2 diabetic humans have indicated that dietary supplementation with L: -Arg can diminish gain in white adipose tissue (WAT) and improve insulin sensitivity. However, the effects of L: -Arg on glucose homeostasis, body composition and energy metabolism remain unclear. In addition, no studies have, to our knowledge, examined whether L: -Arg has beneficial effects as a dietary supplement in the mouse model. In the present study, we investigated the effects of L: -Arg supplementation to male C57BL/6 mice on an array of physiological parameters. L: -Arg supplemented mice were maintained on a low-protein diet and body composition, appetite regulation, glucose tolerance, insulin sensitivity and energy expenditure were evaluated. A significant reduction in epididymal WAT was observed in L: -Arg supplemented mice compared with mice fed an isocaloric control diet. Surprisingly, the L: -Arg supplemented animals were hyperphagic corresponding to a highly significant decrease in feed efficiency, as body weight developed in a similar pattern in both experimental groups. Glucose homeostasis experiments revealed a major effect of L: -Arg supplementation on glucose tolerance and insulin sensitivity, interestingly, independent of a parallel regulation in whole-body adiposity. Increased L: -Arg ingestion also raised energy expenditure; however, no concurrent effect on locomotor activity, substrate metabolism or expression of uncoupling proteins (UCP1 and UCP2) in adipose tissues was displayed. In conclusion, dietary L: -Arg supplementation substantially affects an array of metabolic-associated parameters including a reduction in WAT, hyperphagia, improved insulin sensitivity and increased energy expenditure in mice fed a low-protein diet.

U2 - 10.1007/s00726-011-1199-1

DO - 10.1007/s00726-011-1199-1

M3 - Journal article

C2 - 22200933

VL - 43

SP - 1265

EP - 1275

JO - Amino Acids

JF - Amino Acids

SN - 0939-4451

IS - 3

ER -