Journals of Gerontology Series A: Biological Sciences and Medical Sciences, Vol 53, Issue 2 B94-101, Copyright © 1998 by The Gerontological Society of America
Protein glycation in the aging male Sprague-Dawley rat: effects of antiaging diet restrictions
M Novelli, P Masiello, M Bombara and E Bergamini
Istituto di Patologia Generale, School of Medicine, University of Pisa, Italy.
Protein glycation and accumulation of advanced glycosylated end- products
(AGEs) are supposed to play an important role in the process of aging.
Dietary restriction increases life span and delays the onset of most
age-associated diseases. Age-dependent changes in glucose homeostasis and
glycated plasma proteins and hemoglobin were determined, and AGEs formation
was measured as fluorescence in skin and aortic collagens in male
Sprague-Dawley rats fed ad libitum or subjected to every-other-day feeding
or 40% food restriction. In aging control rats, skin and aortic
collagen-linked fluorescence increased with a similar exponential curve
(aortic value being always higher), whereas glycated plasma protein and
hemoglobin decreased slightly. Dietary restrictions decreased glycated
plasma proteins and fluorescent products in skin collagen of younger but
not older rats, and did not affect glycated hemoglobin or aortic collagen
fluorescence. In conclusion, our data indicate that age-related changes in
glucose homeostasis do not play a substantial role in aging; and collagen-
linked fluorescence increases significantly during aging, but it may not be
sensitive to dietary intervention.
