Effect of oral glutamine supplementation on human neutrophil lipopolysaccharide-stimulated degranulation following prolonged exercise

Int J Sport Nutr Exerc Metab. 2000 Mar;10(1):39-50. doi: 10.1123/ijsnem.10.1.39.


Recent studies have shown that neutrophils can utilize glutamine and that glutamine supplementation can improve neutrophil function in postoperative and burn patients. The present study investigated the influence of oral glutamine supplementation on stimulated neutrophil degranulation and oxidative burst activity following prolonged exercise. Subjects, 7 well-trained men, reported to the laboratory following an overnight fast and cycled for 2 hrs at 60% VO2max on two occasions a week apart. They were randomly assigned to either a glutamine or placebo treatment. For both trials, subjects consumed a sugar-free lemon drink at 15-min intervals until 90 minutes, then a lemon flavored glutamine drink (GLN) or sugar-free lemon drink (PLA) was consumed at 15-min intervals for the remaining exercise and the 2-hr recovery period. Venous blood samples were taken pre-, during, and postexercise. Glutamine supplementation had no effect on the magnitude of postexercise leukocytosis, the plasma elastase concentration following exercise (which increased in both trials), or the plasma elastase release in response to bacterial stimulation (which fell in both trials). Neutrophil function assessed by oxidative burst activity of isolated cells did not change following exercise in either trial. These findings therefore suggest that the fall in plasma glutamine concentration does not account for the decrease in neutrophil function (degranulation response) following prolonged exercise.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Adult
  • Analysis of Variance
  • Blood Glucose / analysis
  • Burns / physiopathology
  • Cell Degranulation / drug effects*
  • Dietary Supplements*
  • Exercise Test
  • Fasting
  • Follow-Up Studies
  • Glutamine / administration & dosage
  • Glutamine / blood
  • Glutamine / therapeutic use*
  • Heart Rate / physiology
  • Humans
  • Leukocytosis / classification
  • Lipopolysaccharides / pharmacology*
  • Male
  • Neutrophil Activation / drug effects
  • Neutrophils / drug effects*
  • Neutrophils / enzymology
  • Neutrophils / physiology
  • Oxygen Consumption / physiology
  • Pancreatic Elastase / blood
  • Pancreatic Elastase / drug effects
  • Physical Exertion / physiology*
  • Placebos
  • Respiratory Burst / drug effects
  • Surgical Procedures, Operative


  • Blood Glucose
  • Lipopolysaccharides
  • Placebos
  • Glutamine
  • Pancreatic Elastase