AJP - Endocrinology and Metabolism, Vol 266, Issue 6 E885-E891, Copyright © 1994 by American Physiological Society

ARTICLES

Effects of puberty and diabetes on metabolism of insulin-sensitive fuels

S. Caprio, G. Cline, S. Boulware, C. Permanente, G. I. Shulman, R. S. Sherwin and W. V. Tamborlane
Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06510.

Insulin's ability to stimulate glucose metabolism is reduced during normal puberty; these changes are exaggerated in adolescents with insulin-dependent diabetes mellitus (IDDM). Because the effects of puberty and IDDM on the other actions of insulin have not been established, we studied leucine kinetics (using [1-13C]leucine) and fat metabolism during euglycemic hyperinsulinemia (20 mU.m2.min-1) for 3 h in eight healthy and nine IDDM (HbA1 14 +/- 2%) adolescents and six healthy young adult controls. IDDM subjects received overnight low-dose insulin infusion to normalize fasting glucose. Basal and steady-state insulin values (approximately 240 pM) during the study were similar in all three groups. Insulin-stimulated glucose metabolism was reduced by 40% in healthy adolescents vs. adults (P < 0.05) and by an additional 40% in poorly controlled IDDM (P < 0.05 vs, normal adolescents). Although basal glucose and lipid oxidation rates (measured by indirect calorimetry) were similar in all three groups, when insulin was infused, glucose oxidation increased and lipid oxidation decreased only in the two nondiabetic groups. Similarly, insulin significantly reduced plasma free fatty acid levels only in the nondiabetics. Basal leucine flux (an index of protein degradation) was similar in healthy controls but was markedly increased in IDDM adolescents. Despite similar increments in plasma insulin during the clamp, leucine flux remained higher in IDDM adolescents than in healthy controls. Basal leucine oxidation rates were also increased in IDDM subjects compared with nondiabetic groups and declined to a lesser extent during insulin infusion. We conclude that insulin resistance of puberty is selective for glucose metabolism, sparing amino acid/protein metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)

This article has been cited by other articles:

				G. Perseghin, R. Bonfanti, S. Magni, G. Lattuada, F. De Cobelli, T. Canu, A. Esposito, P. Scifo, G. Ntali, F. Costantino, et al. Insulin resistance and whole body energy homeostasis in obese adolescents with fatty liver disease Am J Physiol Endocrinol Metab, October 1, 2006; 291(4): E697 - E703. [Abstract] [Full Text] [PDF]

				M. I. Goran and B. A. Gower Longitudinal Study on Pubertal Insulin Resistance Diabetes, November 1, 2001; 50(11): 2444 - 2450. [Abstract] [Full Text] [PDF]

				S. Banerjee, P. Saenger, M. Hu, W. Chen, and N. Barzilai Fat accretion and the regulation of insulin-mediated glycogen synthesis after puberty in rats Am J Physiol Regulatory Integrative Comp Physiol, October 1, 1997; 273(4): R1534 - R1539. [Abstract] [Full Text] [PDF]