title: Effects of intragastric administration of five oyster components on endurance exercise performance in mice.
abstract: BACKGROUND
  Oysters [Crassostrea plicatula Gmelin (Ostreidae)] are widely used for food in coastal areas. It is reported to have several qualities such as improving sexual and immune function. They has been approved by Chinese Ministry of Health as a functional food.
  
  
  OBJECTIVE
  The effects of five types of oyster components (oyster meat, oyster glycogen, oyster protein, cooked liquid components, and water-insoluble components) on the swimming endurance of mice were investigated.
  
  
  METHODS
  First, the amino acid composition and sugar content of the five oyster components were analyzed by a physicochemical test. In the in vivo test, the control group was administered distilled water, and the five intervention groups were treated with various samples for 15 consecutive days [0.8 mg protein/(g BW·d) or 0.2 mg glycogen/(g BW·d)]. The swimming time was recorded through the exhaustive swimming test. The levels of serum lactic acid, blood urea nitrogen (BUN), liver glycogen, and gastrocnemius muscle glycogen were determined.
  
  
  RESULTS
  Oyster protein had a minimum F-value (the mole ratio of branched-chain amino acids to aromatic amino acids) (2.68), contained 1.85 mmol/mL taurine and no sugar. The components (except for oyster protein) significantly improved endurance capacity of mice and increased the liver and muscle glycogen contents (p<0.05), and reduced the lactic acid and BUN levels (p<0.05). Oyster protein had little effect.
  
  
  CONCLUSIONS
  The effects of oyster components on the swimming endurance of mice may be attributed to the high ratio of the branched-chain amino acid composition, bioactivity of taurine, and glycogen.
authors.affiliation: College of Biological Engineering, Jimei University , Xiamen , China .
authors.forename: Gengxin
authors.initials: G
authors.lastname: Hao
authors.forename: Chaohua
authors.initials: C
authors.lastname: Zhang
authors.forename: Wenhong
authors.initials: W
authors.lastname: Cao
authors.forename: Jiming
authors.initials: J
authors.lastname: Hao
mesh_terms: D000818:Animals; D049896:Crassostrea; D006003:Glycogen / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D019344:Lactic Acid / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism; D010805:Physical Conditioning, Animal / Q000379:methods / Q000502:physiology*; D010807:Physical Endurance / Q000187:drug effects / Q000502:physiology*; D012758:Shellfish; D013550:Swimming / Q000502:physiology*
chemical_list: D019344:Lactic Acid; D006003:Glycogen
keywords: Biochemical analysis; fatigue; nutritional ingredient