Impact of moderate physical exercise--in comparison with dietary restrictions--on age-associated decline in cell-mediated immunity of Sprague-Dawley rats.
OBJECTIVE
Moderate physical exercise and dietary restriction have both been demonstrated to delay some of the adverse effects of aging. In order to elucidate similarities or dissimilarities in their mode of action on the aging immune system in a comparative setting, we examined significant parameters of cell-mediated immunity in Sprague- Dawley rats.


METHODS
Male Sprague-Dawley rats, housed individually, were divided into four groups, living from 5 months (baseline group BL) up to 15, 19 and 23 months of age as follows: voluntary running in wheels (RW), food restricted by feeding to pair weight with RW animals (PW), forced running on treadmills (TM), and sedentary controls with ad libitum access to food (S1). White blood cell counts, capacity for lymphocyte proliferation in response to Concanavalin A, and interleukin-2 (IL-2) plasma concentrations were determined.


RESULTS
White blood cell counts and the cell numbers of lymphocytes, neutrophil and eosinophil granulocytes were significantly lower in the older RW and PW groups. We observed influences of forced exercise on lymphocyte proliferation: blastogenic reactivity was higher in TM animals compared with RW and PW animals at 23 months of age. Exclusively for RW animals, we found lower plasma concentrations of IL-2 at 23 months.


CONCLUSIONS
Our data support the idea that moderate physical exercise modulates age-associated decline in the cell-mediated immunity of old Sprague-Dawley rats significantly more than corresponding dietary restrictions.
Strasser
Alois
A
Department of Natural Sciences, Institute of Physiology, University of Veterinary Medicine Vienna, 1210 Wien, Austria. alois.strasser@vu-wien.ac.at
Skalicky
Monika
M
Viidik
Andrus
A
D000375:Aging / Q000276:immunology*; D000818:Animals; D031204:Caloric Restriction; D007111:Immunity, Cellular / Q000502:physiology*; D007376:Interleukin-2 / Q000097:blood; D007958:Leukocyte Count; D008297:Male; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D007376:Interleukin-2