Life-Span Study of SPF Fischer 344 Male Rats Fed Ad Libitum or Restricted Diets: Longevity, Growth, Lean Body Mass and Disease

2002 ◽  
Vol 2002 (37) ◽  
Author(s):  
Byung Pal Yu ◽  
Edward J. Masoro ◽  
Ikuo Murata ◽  
Helen A. Bertrand ◽  
Frederick T. Lynd
Keyword(s):  
Life Span ◽  
Lean Body Mass ◽  
Body Mass ◽  
Food Restriction ◽  
Male Rats ◽  
Life Span Study ◽  
Renal Lesions ◽  
Fischer 344 ◽  
Group A ◽  
Ad Libitum

A life-span study was carried out on longevity, pathologic lesions, growth, lean body mass, and selected aspects of muscle of barrier-maintained SPF Fischer 344 rats fed either ad libitum (Group A) or 60% of the ad libitum intake (Group R). Food restriction was as effective in prolonging the life of already long-lived SPF rats as previously shown for rats maintained in conventional facilities. Food restriction not only increased the mean length of life but also acted to extend life-span since more than 60% of the Group R rats lived longer than the longest lived Group A rat. Renal lesions occurred at an earlier age in Group A rats than in Group R rats and progressed more rapidly. Death of most Group A rats was associated with severe renal lesions while few Group R rats showed such lesions at death. Food restriction was also found to delay or prevent interstitial cell tumors of the testes, bile duct hyperplasia, myocardial fibrosis and myocardial degeneration. Gastrocnemius muscle mass declined in advanced age and food restriction delayed this decline. Interestingly, however, lean body mass did not progressively decline with increasing age but rather decline occurred only after the onset of the terminal disease process. Copyright (c) The Gerontological Society of America. Reproduced by permission of the publisher. Byung Pal Yu, Edward J. Masoro, Ikuo Murata, Helen A. Bertrand, Frederick T. Lynd, Life Span Study of SPF Fischer 344 Male Rats Fed Ad Libitum or Restricted Diets: Longevity, Growth, Lean Body Mass and Disease. J. Gerontol. 37 , 130-141 (1982).

Life Span Study of SPF Fischer 344 Male Rats Fed AdLibitum or Restricted Diets: Longevity, Growth, Lean Body Mass and Disease

1982 ◽  
Vol 37 (2) ◽  
pp. 130-141 ◽  
Author(s):  
B. P. Yu ◽  
E. J. Masoro ◽  
I. Murata ◽  
H. A. Bertrand ◽  
F. T. Lynd
Keyword(s):  
Life Span ◽  
Lean Body Mass ◽  
Body Mass ◽  
Male Rats ◽  
Life Span Study ◽  
Fischer 344

Does food restriction retard aging by reducing the metabolic rate?

1985 ◽  
Vol 248 (4) ◽  
pp. E488-E490 ◽  
Author(s):  
R. McCarter ◽  
E. J. Masoro ◽  
B. P. Yu
Keyword(s):  
Metabolic Rate ◽  
Lean Body Mass ◽  
Body Mass ◽  
Food Restriction ◽  
Aging Process ◽  
Male Rats ◽  
Short Term ◽  
Ad Libitum ◽  
Group 2 ◽  
Group 1

Metabolic rate was determined by measuring O2 consumption in two groups of 6-mo-old male rats fed ad libitum (group 1) or maintained on a life-prolonging food-restriction regimen for 4.5 mo (group 2). These measurements were made continuously for 23.75 h under conditions nearly identical to those of the daily life of the rats. The metabolic rate per kilogram lean body mass was the same for both groups, a finding contrary to the hypothesis that food restriction retards the aging process and prolongs life by slowing the metabolic rate per unit of metabolic mass. This and our previous work strongly suggest that the classic views of the action of food restriction on aging must be re-evaluated because retardation of the aging process can occur without the restriction of calories or any other nutrient per unit of lean body mass. The long held belief that reducing food intake lowers the metabolic rate per unit of metabolic mass may be true in short-term dietary programs but appears not to be true when a significant portion of the life span is involved.

Selected Contribution: Bone adaptation with aging and long-term caloric restriction in Fischer 344 × Brown-Norway F1-hybrid rats

2003 ◽  
Vol 95 (4) ◽  
pp. 1739-1745 ◽  
Author(s):  
Jeremy M. LaMothe ◽  
Russell T. Hepple ◽  
Ronald F. Zernicke
Keyword(s):  
Life Span ◽  
Caloric Restriction ◽  
Structural Properties ◽  
Body Mass ◽  
Bone Geometry ◽  
Bone Adaptation ◽  
Brown Norway ◽  
F1 Hybrid ◽  
Fischer 344 ◽  
Ad Libitum

Rodents are commonly used as models for human aging because of their relatively short life span, the ease of obtaining age-specific tissue samples, and lower cost. However, age-associated disease may confound inbred animal studies. For example, numerous physiologically significant lesions, such as chronic nephropathy, are more common in aged Fischer 344 (F344) rats than in other strains (Bronson RT, Genetic Effects of Aging, 1990). Conversely, F344 × Brown-Norway F1-hybrid (F344BN) rats, developed by the National Institute on Aging for aging research, live considerably longer and have fewer pathologies at any given age vs. inbred strains (Lipman RD, Chrisp CE, Hazzard DG, and Bronson RT, J Gerontol A Biol Sci Med Sci 51: 54-59, 1996). To our knowledge, there are no data regarding the effect of age on bone geometry and mechanics in this strain of rat. Furthermore, caloric restriction (CR) extends the mean and maximal life span of animals and significantly reduces age-associated disease but may have adverse consequences for bone growth and mechanics. Thus we investigated the effects of age and CR on bone geometry and mechanics in the axial and appendicular skeleton of F344 Brown-Norway rats. Ad libitum fed rats were assessed at 8 mo (young adult; n = 6), 28 mo (late middle age; n = 5), and 36 mo (senescence; n = 6). CR rats were assessed at 28 mo ( n = 6). Tibiae and the sixth lumbar vertebrae (L6) were dissected, scanned (micro-computed tomography) to determine geometry, and tested mechanically. From 8 to 36 mo, there were no significant changes in L6 geometry, and only the cross-sectional moment of inertia changed (increased) with the tibia. CR-induced body mass reductions accounted for changes in L6 load at proportional limit, maximal load, and stiffness (structural properties), but altered tibial structural properties were independent of body mass. In tibiae, geometric changes dominated alterations in structural properties. Those data demonstrated that, whereas aging in ad libitum-fed animals induced minor changes in bone mechanics, axial and appendicular bones were adversely influenced by CR in late-middle-aged animals in different manners.

Energy metabolism and aging: a lifelong study of Fischer 344 rats

1992 ◽  
Vol 263 (3) ◽  
pp. E448-E452 ◽  
Author(s):  
R. J. McCarter ◽  
J. Palmer
Keyword(s):  
Energy Metabolism ◽  
Metabolic Rate ◽  
Food Restriction ◽  
Fischer 344 Rats ◽  
Fuel Utilization ◽  
Fischer 344 ◽  
Group A ◽  
Ad Libitum ◽  
Group B ◽  
Ad Libitum Intake

Metabolic rate is widely regarded as an important component of aging processes, but variation of metabolic rate with age has not been well characterized. The purpose of the present study was to measure daily metabolic rate under usual living conditions over the lifespan of barrier-maintained Fischer 344 rats. In addition, effects of life-prolonging food restriction were assessed. Metabolic rate was measured indirectly by analysis of gas entering and leaving standard rodent cages over a 24-h period. Group A rats were fed ad libitum. Group B rats were fed 60% of ad libitum intake from 6 wk of age. Both group A and group B rats exhibited variation of metabolic rate per unit lean mass over the lifespan, with metabolic rate decreasing from 6 to 18 mo and then increasing from 18 to 24 mo of age. Results show estimates of lifetime energy expenditure in rats should take account of variability of metabolic rate and confirm the life-prolonging action of food restriction is not a consequence of reduced metabolic rate per unit metabolic mass. Rather, restricted rats are able to sustain appropriate fluxes of nutrients and appropriate metabolic rate under conditions of fuel utilization which promote maintenance of cellular homeostasis.

Rat muscle structure and metabolism in relation to age and food intake

1982 ◽  
Vol 242 (1) ◽  
pp. R89-R93 ◽  
Author(s):  
R. J. McCarter ◽  
E. J. Masoro ◽  
B. P. Yu
Keyword(s):  
Oxygen Consumption ◽  
Muscle Mass ◽  
Food Restriction ◽  
Fiber Diameter ◽  
Male Rats ◽  
Progressive Loss ◽  
Age Related ◽  
Group A ◽  
Ad Libitum ◽  
Ad Libitum Intake

Age changes in oxygen consumption and the structural composition of the lateral omohyoideus muscle were studied in adult male rats. The rate were either fed ad libitum (group A) or 60% of the ad libitum intake (group R). An age-related loss in muscle mass did not occur even at advanced ages in group A or group R rats. Muscle fiber diameter decreased with age in both groups but a concomitant increase in the number of fibers prevented a change in muscle mass. The muscles of group R rats contained the same number of fibers as those of group A rats at all ages. The muscles of group A rats showed a progressive loss in rate of resting oxygen consumption until 18 mo of age. A similar but less marked loss in oxygen consumption occurred in the muscles of group R rats. These results provide further evidence that life-prolonging food restriction modulates physiological changes associated with the aging process.

Exercise and body composition

1991 ◽  
Vol 70 (3) ◽  
pp. 994-997 ◽  
Author(s):  
G. B. Forbes
Keyword(s):  
Young Adults ◽  
Body Composition ◽  
Lean Body Mass ◽  
Body Mass ◽  
Body Fat ◽  
Training Programs ◽  
Published Data ◽  
Additional Information ◽  
Body Fat Content ◽  
Ad Libitum

We assessed changes in body composition in 41 young adults who engaged in various exercise and/or training programs on ad libitum diets. Most of those who gained weight sustained an increase in lean body mass (LBM), and most of those who lost weight lost LBM as well as fat. The change in LBM was directly related to the change in weight, with a regression slope of 0.500. An analysis of published data confirms these findings and, in concert with our data, provides the additional information that the magnitude of the change in body composition in exercising individuals is influenced by body fat content, just as it is for nonexercising individuals.

FOOD CONSUMPTION AND RECTAL TEMPERATURE IN RATS DURING THIAMINE DEFICIENCY AND REPLETION

1963 ◽  
Vol 41 (12) ◽  
pp. 2463-2471 ◽  
Author(s):  
M. J. Veen ◽  
G. Russell ◽  
G. H. Beaton
Keyword(s):  
Food Consumption ◽  
Rectal Temperature ◽  
Food Restriction ◽  
Control Diet ◽  
Significant Rise ◽  
Male Rats ◽  
Thiamine Hydrochloride ◽  
Deficient Diet ◽  
Ad Libitum ◽  
Deficient Group

Rectal temperature in male rats fell slowly and gradually from ad libitum and pair-led control levels throughout a thiamine depletion period. During this period, food consumption dropped suddenly and sharply to a minimal level. A single oral dose of 50 μg of thiamine hydrochloride produced, within 4 hours, a significant rise (to less than control levels) in rectal temperature and an increase in food consumption within 24 hours. The increase in temperature was independent of the ingestion of food since diet was withheld during the 4 hours following thiamine administration. Subsequent feeding of control diet (containing thiamine) had not further increased the "4-hour" temperature after 24 hours. With continued feeding of control diet, rectal temperature rose to control levels after 3 days. On subsequent withdrawal of dietary thiamine from the deficient group, temperature and food consumption fell as before. When the animals were again repleted with 50 μg thiamine and deficient diet was continued, temperatures rose to the same level reached after the first thiamine administration. A third deprivation and repletion produced identical results.Food restriction alone, in pair-fed control groups, induced an initial elevation of rectal temperature above ad libitum control levels as temperatures in the deficient group were falling, and an eventual decrease below ad libitum control levels only after prolonged food restriction. It is suggested that the initial fall in body temperature in thiamine-deficient rats is not simply a terminal result of food restriction per se, but may reflect alterations in metabolism due to the deficiency.

Circulating hyaluronan levels in the rodent: effects of age and diet

1995 ◽  
Vol 268 (4) ◽  
pp. C952-C957 ◽  
Author(s):  
J. Yannariello-Brown ◽  
S. H. Chapman ◽  
W. F. Ward ◽  
T. C. Pappas ◽  
P. H. Weigel
Keyword(s):  
Fish Meal ◽  
Caloric Intake ◽  
Protein Source ◽  
Male Rats ◽  
Semisynthetic Diet ◽  
Fischer 344 ◽  
Age Related ◽  
Old Rats ◽  
Ad Libitum ◽  
Age Related Changes

Circulating hyaluronan (HA) levels were investigated as a function of age and diet in Fischer 344 male rats. A biphasic pattern of age-related changes was observed in rats fed ad libitum a diet in which the protein source was soya/fish meal. HA levels in 3- to 6- and 22- to 29-mo-old rats were not statistically different. However, HA levels in 12- to 20-mo-old rats were 10-29% of the levels in younger or aged adults. HA levels were also measured in rats fed ad libitum a semisynthetic diet in which the protein source was hydrolyzed casein. Whereas the two colonies exhibited similar biphasic age-related changes, HA levels differed 4- to 20-fold at every age examined. Caloric restriction affected HA levels in 19-mo-old casein-fed rats; HA levels were 2.3 times higher than age-matched controls and were not statistically different from young or aged animals. Serum and plasma HA levels were identical in the same individuals at all ages tested. These data suggest that HA turnover and metabolism in the rat are affected by age, dietary composition, and caloric intake.

A note on the combined effects of exercise and food restriction on plasma enzyme activities in the rat

1969 ◽  
Vol 47 (4) ◽  
pp. 396-398 ◽  
Author(s):  
J. R. Beaton ◽  
B. Oyster
Keyword(s):  
Food Restriction ◽  
Acute Exercise ◽  
Male Rats ◽  
Elevated Plasma ◽  
Malic Dehydrogenase ◽  
Individual Effects ◽  
Ad Libitum ◽  
The Individual ◽  
Exercise And Training ◽  
And Training

Plasma activities of malic dehydrogenase (MDH) and glutamic–pyruvic transaminase (GPT) were measured in adult male rats made to swim for 1 h either as a single, acute exercise or in repeated exercises (training) in the presence of a 50% food restriction. Food restriction per se elevated MDH and lowered GPT activities. Food-restricted rats responded to both acute exercise and training by an elevated plasma MDH activity. The effect of exercise on plasma MDH activity in these animals was greater than in rats fed ad libitum and was greater than could be accounted for by the summation of the individual effects of training and of food restriction. Plasma GPT activity was not altered by exercise in rats fed ad libitum or in food-restricted animals. It would appear, as suggested previously, that plasma MDH activity may be a useful biochemical criterion of training.

Sign in / Sign up

Export Citation Format

Share Document