497. Central CART Gene Delivery by Recombinant AAV Vector Decreases Lean Body Mass in Diet-Induced Obese Male Rats

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.

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

Science of Aging Knowledge Environment ◽

10.1126/sageke.2002.37.cp18 ◽

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).

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Inulin and thiocyanate spaces of rat in starvation and undernutrition

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1961.201.2.329 ◽

1961 ◽

Vol 201 (2) ◽

pp. 329-333 ◽

Cited By ~ 2

Author(s):

Ashton B. Morrison

Keyword(s):

Body Weight ◽

Lean Body Mass ◽

Body Mass ◽

The Body ◽

Male Rats ◽

Normal Male ◽

Free Access ◽

Final Body Weight ◽

Absolute Increase ◽

Inulin Space

Inulin space and thiocyanate space determinations were made on three groups of male rats: the first group was chronically undernourished by feeding a restricted ration for 10 weeks, the second group was starved with free access to water, and the third was made up of normal male controls. The inulin space was found to expand relative to the final body weight or lean body mass in the undernourished animal. No absolute increase in inulin space took place. In starvation the inulin space did not change in proportion to the body weight and its absolute value decreased. The thiocyanate space relative to the final body weight or lean body mass expanded slightly but significantly in chronic undernutrition and in starvation, but no absolute increase of the thiocyanate space took place.

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