title: Branched-chain amino acid supplementation and the immune response of long-distance athletes.
abstract: OBJECTIVE
  Intense long-duration exercise has been associated with immunosuppression, which affects natural killer cells, lymphokine-activated killer cells, and lymphocytes. The mechanisms involved, however, are not fully determined and seem to be multifactorial, including endocrine changes and alteration of plasma glutamine concentration. Therefore, we evaluated the effect of branched-chain amino acid supplementation on the immune response of triathletes and long-distance runners.
  
  
  METHODS
  Peripheral blood was collected prior to and immediately after an Olympic Triathlon or a 30k run. Lymphocyte proliferation, cytokine production by cultured cells, and plasma glutamine were measured.
  
  
  RESULTS
  After the exercise bout, athletes from the placebo group presented a decreased plasma glutamine concentration that was abolished by branched-chain amino acid supplementation and an increased proliferative response in their peripheral blood mononuclear cells. Those cells also produced, after exercise, less tumor necrosis factor, interleukins-1 and -4, and interferon and 48% more interleukin-2. Supplementation stimulated the production of interleukin-2 and interferon after exercise and a more pronounced decrease in the production of interleukin-4, indicating a diversion toward a Th1 type immune response.
  
  
  CONCLUSIONS
  Our results indicate that branched-chain amino acid (BCAA) supplementation recovers the ability of peripheral blood mononuclear cells proliferate in response to mitogens after a long distance intense exercise, as well as plasma glutamine concentration. The amino acids also modify the pattern of cytokine production leading to a diversion of the immune response toward a Th1 type of immune response.
authors: Department of Histology and Embryology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
authors: Reinaldo A
authors: RA
authors: Bassit
authors: Letícia A
authors: LA
authors: Sawada
authors: Reury F P
authors: RF
authors: Bacurau
authors: Franciso
authors: F
authors: Navarro
authors: Eivor
authors: E
authors: Martins
authors: Ronaldo V T
authors: RV
authors: Santos
authors: Erico C
authors: EC
authors: Caperuto
authors: Patrícia
authors: P
authors: Rogeri
authors: Luís F B P
authors: LF
authors: Costa Rosa
mesh_terms: D000328:Adult; D000597:Amino Acids, Branched-Chain / Q000008:administration & dosage* / Q000097:blood; D001642:Bicycling / Q000502:physiology; D016207:Cytokines / Q000097:blood; D019587:Dietary Supplements; D005973:Glutamine / Q000097:blood; D006801:Humans; D007107:Immune System / Q000187:drug effects* / Q000502:physiology; D007111:Immunity, Cellular / Q000187:drug effects / Q000502:physiology; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D010807:Physical Endurance / Q000187:drug effects / Q000502:physiology*; D012420:Running / Q000502:physiology; D013550:Swimming / Q000502:physiology
chemical_list: D000597:Amino Acids, Branched-Chain; D016207:Cytokines; D005973:Glutamine