title: Long-term leucine supplementation reduces fat mass gain without changing body protein status of aging rats.
abstract: OBJECTIVE
  Aging is characterized by alterations in body composition such as an increase in body fat and decreases in muscle mass (sarcopenia) and bone density (osteopenia). Leucine supplementation has been shown to acutely stimulate protein synthesis and to decrease body fat. However, the long-term effect of consistent leucine supplementation is not well defined. This study investigated the effect of leucine supplementation during aging.
  
  
  METHODS
  Six-month-old rats were divided into three groups: an adult group (n = 10) euthanized at 6 mo of age, a leucine group (n = 16) that received a diet supplemented with 4% leucine for 40 wk, and a control group (n = 19) that received the control diet for 40 wk. The following parameters were evaluated: body weight, food intake, chemical carcass composition, indicators of acquired chronic diseases, and indicators of protein nutritional status.
  
  
  RESULTS
  Body weight and fat were lower in the leucine group after 40 wk of supplementation compared with the control group but still higher than in the adult group. The lipid and glycemic profiles were equally altered in the control and leucine groups because of aging. In addition, leucine supplementation did not affect the changes in protein status parameters associated with aging, such as decreases in body and muscle protein and total serum protein.
  
  
  CONCLUSIONS
  The results indicate that leucine supplementation attenuates body fat gain during aging but does not affect risk indicators of acquired chronic diseases. Furthermore, supplemented animals did not show signs of a prevention of the decrease in lean mass associated with aging.
authors.affiliation: Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Daiana
authors.initials: D
authors.lastname: Vianna
authors.forename: Gabriela Fulin Teodoro
authors.initials: GF
authors.lastname: Resende
authors.forename: Francisco Leonardo
authors.initials: FL
authors.lastname: Torres-Leal
authors.forename: Lucas Carminatti
authors.initials: LC
authors.lastname: Pantaleão
authors.forename: Jose
authors.initials: J
authors.lastname: Donato
authors.forename: Julio
authors.initials: J
authors.lastname: Tirapegui
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects* / Q000378:metabolism; D000367:Age Factors; D000375:Aging / Q000502:physiology*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000187:drug effects*; D001825:Body Fluid Compartments / Q000187:drug effects / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002908:Chronic Disease; D019587:Dietary Supplements; D007930:Leucine / Q000008:administration & dosage / Q000494:pharmacology*; D008055:Lipids / Q000097:blood; D008297:Male; D009752:Nutritional Status; D009765:Obesity / Q000378:metabolism / Q000517:prevention & control*; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012307:Risk Factors
chemical_list: D001786:Blood Glucose; D008055:Lipids; D011506:Proteins; D007930:Leucine