Aging and insulin secretion.
Glucose tolerance progressively declines with age, and there is a high prevalence of type 2 diabetes and postchallenge hyperglycemia in the older population. Age-related glucose intolerance in humans is often accompanied by insulin resistance, but circulating insulin levels are similar to those of younger people. Under some conditions of hyperglycemic challenge, insulin levels are lower in older people, suggesting beta-cell dysfunction. When insulin sensitivity is controlled for, insulin secretory defects have been consistently demonstrated in aging humans. In addition, beta-cell sensitivity to incretin hormones may be decreased with advancing age. Impaired beta-cell compensation to age-related insulin resistance may predispose older people to develop postchallenge hyperglycemia and type 2 diabetes. An improved understanding of the metabolic alterations associated with aging is essential for the development of preventive and therapeutic interventions in this population at high risk for glucose intolerance.
Chang
Annette M
AM
Divisions of Endocrinology and Geriatric Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor 48109, USA. annchang@umich.edu
Halter
Jeffrey B
JB
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000503:physiopathology; D005934:Glucagon; D052216:Glucagon-Like Peptide 1; D004763:Glucagon-Like Peptides; D018149:Glucose Intolerance / Q000453:epidemiology; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D007333:Insulin Resistance; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000503:physiopathology; D008875:Middle Aged; D009749:Nutrition Surveys; D010446:Peptide Fragments / Q000494:pharmacology
D007328:Insulin; D010446:Peptide Fragments; C055453:glucagon-like peptide 1 (7-36)amide; D004763:Glucagon-Like Peptides; D052216:Glucagon-Like Peptide 1; D005934:Glucagon