The effects of different levels of dietary restriction on non-neoplastic diseases in male Sprague-Dawley rats.
OBJECTIVE
The primary purpose of the present study was to investigate the effects of 10, 25, and 40% dietary restriction (DR) on non-neoplastic diseases in rodents at 58 and 110 weeks of age, and to determine whether low-level DR (10 and 25%) can increase the survival rate and decrease variability in chronic bioassay studies.


METHODS
Male Sprague-Dawley (SD) rats (NCTR colony) were divided into four nutritional groups, consisting of an ad libitum (AL) group with unlimited access to the NIH-31 diet, and three dietary restricted (DR) groups given the NIH-31 diet reduced in amount by 10, 25, and 40%.


RESULTS
At 110 weeks of age, the incidence of cardiomyopathy was 95, 75, 45, and 15% for AL and 10, 25, and 40% DR rats, respectively; the incidence of nephropathy was 55, 20, 15, and 0% for AL and 10, 25, and 40% DR rats, respectively. The severity of chronic heart and kidney diseases was significantly reduced in all DR rat groups, with significant DR-dependent linear trends for these diseases. Moreover, DR prevented the progression of skin irritation to foot ulcers, and reduced the age-related degeneration in the adrenal, lacrimal, and thymus glands, and the liver.


CONCLUSIONS
These results clearly indicate that even low DR levels were effective in preventing or slowing the progression of these non-neoplastic diseases.
Duffy
Peter H
PH
Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA. pduffy@nctr.fda.gov
Lewis
Sherry M
SM
Mayhugh
Martha A
MA
Trotter
Ronald W
RW
Thorn
Brett T
BT
Feuers
Ritchie J
RJ
Turturro
Angelo
A
D000375:Aging / Q000502:physiology; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D009202:Cardiomyopathies / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D002908:Chronic Disease; D004032:Diet; D018450:Disease Progression; D005508:Food Deprivation; D006801:Humans; D007674:Kidney Diseases / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D008136:Longevity; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley