Carbohydrate Supplementation Influences Serum Cytokines after Exercise under Hypoxic Conditions.
BACKGROUND
Exercise performed at the hypoxia equivalent of an altitude of 4200 m is associated with elevated inflammatory mediators and changes in the Th1/Th2 response. By contrast, supplementation with carbohydrates has an anti-inflammatory effect when exercise is performed under normoxic conditions. The objective of this study was to evaluate the effect of carbohydrate supplementation on cytokines and cellular damage markers after exercise under hypoxic conditions at a simulated altitude of 4200 m.


METHODS
Seven adult male volunteers who exercised for 60 min at an intensity of 50% VO2Peakwere randomly evaluated under three distinct conditions; normoxia, hypoxia and hypoxia + carbohydrate supplementation. Blood samples were collected at rest, at the end of exercise and after 60 min of recovery. To evaluate hypoxia + carbohydrate supplementation, volunteers received a solution of 6% carbohydrate (maltodextrin) or a placebo (strawberry-flavored Crystal Light®; Kraft Foods, Northfield, IL, USA) every 20 min during exercise and recovery. Statistical analyses comprised analysis of variance, with a one-way ANOVA followed by the Tukey post hoc test with a significance level ofp< 0.05.


RESULTS
Under normoxic and hypoxic conditions, there was a significant increase in the concentration of IL-6 after exercise and after recovery compared to at rest (p< 0.05), while in the hypoxia + carbohydrate group, there was a significant increase in the concentration of IL-6 and TNF-α after exercise compared to at rest (p< 0.05). Furthermore, under this condition, TNF-α, IL-2 and the balance of IL-2/IL-4 were increased after recovery compared to at rest (p< 0.05).


CONCLUSIONS
We conclude that carbohydrate supplementation modified the IL-6 and TNF-α serum concentrations and shifted the IL-2/IL-4 balance towards Th1 in response without glycemic, glutaminemia and cell damage effects.
Department of Psychobiology, Universidade Federal de São Paulo, São Paulo 04021-001, Brazil. alinecaris@hotmail.com.
Aline Venticinque
AV
Caris
Department of Bioscience, Universidade Federal de São Paulo, Santos 11060-001, Brazil. edgartavares@uol.com.br.
Edgar Tavares
ET
Da Silva
Department of Bioscience, Universidade Federal de São Paulo, Santos 11060-001, Brazil. samile.unifesp@gmail.com.
Samile Amorim
SA
Dos Santos
Department of Physical Education, Universidade Estadual Paulista, Presidente Prudente 19060-900, Brazil. fslira@gmail.com.
Fabio Santos
FS
Lira
Department of Physiology, Universidade Federal de São Paulo, São Paulo 04021-001, Brazil. lmoyama@gmail.com.
Lila Missae
LM
Oyama
Department of Bioscience, Universidade Federal de São Paulo, Santos 11060-001, Brazil. sergiotufik@zipmail.com.br.
Sergio
S
Tufik
Department of Bioscience, Universidade Federal de São Paulo, Santos 11060-001, Brazil. ronaldo.thomatieli@unifesp.br.
Ronaldo Vagner Thomatieli
RV
Dos Santos
D000328:Adult; D000532:Altitude Sickness / Q000097:blood*; D016207:Cytokines / Q000097:blood*; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D019587:Dietary Supplements; D015444:Exercise / Q000502:physiology*; D006801:Humans; D007249:Inflammation / Q000097:blood*; D007376:Interleukin-2 / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption; D010919:Placebos; D011134:Polysaccharides / Q000008:administration & dosage; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D016207:Cytokines; D004040:Dietary Carbohydrates; D007376:Interleukin-2; D015850:Interleukin-6; D010919:Placebos; D011134:Polysaccharides; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4; C008315:maltodextrin; D010100:Oxygen
IL-2/IL-4; carbohydrate; exercise; hypoxia; immune system; supplementation