title: Long-term voluntary exercise, representing habitual exercise, lowers visceral fat and alters plasma amino acid levels in mice.
abstract: OBJECTIVE
  To determine the impact of long-term voluntary exercise, representing habitual exercise for the prevention of lifestyle-related diseases, on glucose, lipid, and amino acid metabolism in mice.
  
  
  METHODS
  Twenty-four mice aged 6 weeks were divided into three groups. Two groups (16 mice) were housed individually in either cages equipped with a running wheel (8 mice, exercising, Ex-mice) or without (8 mice, sedentary, Se-mice) for 24 weeks. The remaining group (8 mice) was sacrificed at 6 weeks of age. Biomarkers related to glucose, lipid, and amino acid metabolism were examined.
  
  
  RESULTS
  Ex-mice ran voluntarily, predominantly in the dark. The distance per day peaked at 4 weeks and then decreased until 12 weeks to around the level seen at the beginning of the experimental period, and was maintained at 4.9 ± 0.2 km/day from 12 to 24 weeks. Ex-mice showed a similar adrenal weight and vitamin C content to Se-mice but had a significantly lower body weight and higher food intake. Ex-mice also showed a higher skeletal muscle weight, a lower white adipose tissue and liver weight, associated with lower plasma leptin and insulin-like growth factor-1 levels, and a lower hepatic triglyceride content. Analysis of plasma amino acids showed that Ex-mice had significantly higher phenylalanine, tyrosine, and glutamine levels, resulting in a significantly lower Fischer's ratio.
  
  
  CONCLUSIONS
  We present an animal model of long-term voluntary exercise under low stress. Findings related to the effects of long-term voluntary exercise on lipid, and amino acid metabolism in our mouse model indicate that such an exercise regimen may affect pathophysiological states related to appetite and behavior.
authors: Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544, Japan.
authors: Haruko
authors: H
authors: Takeshita
authors: Masahisa
authors: M
authors: Horiuchi
authors: Kimiko
authors: K
authors: Izumo
authors: Hiroaki
authors: H
authors: Kawaguchi
authors: Emi
authors: E
authors: Arimura
authors: Kohji
authors: K
authors: Aoyama
authors: Toru
authors: T
authors: Takeuchi
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000596:Amino Acids / Q000097:blood*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D001823:Body Composition; D004435:Eating; D005260:Female; D005786:Gene Expression Regulation; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism; D051379:Mice; D023421:Models, Animal; D005082:Physical Exertion; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D013997:Time Factors
chemical_list: D000596:Amino Acids; D001786:Blood Glucose; D012333:RNA, Messenger