Quercetin's influence on exercise-induced changes in plasma cytokines and muscle and leukocyte cytokine mRNA.
Trained male cyclists (n = 40) ingested quercetin (Q; n = 20) (1,000 mg/day) or placebo (P; n = 20) supplements under randomized, double-blinded methods for 3 wk before and during a 3-day period in which subjects cycled for 3 h/day at approximately 57% maximal work rate. Blood samples were collected before and after each exercise session and assayed for plasma IL-6, IL-10, IL-1ra, IL-8, TNF-alpha, and monocyte chemoattractant protein 1, and leukocyte IL-10, IL-8, and IL-1ra mRNA. Muscle biopsies were obtained before and after the first and third exercise sessions and assayed for NF-kappaB and cyclooxygenase-2 (COX-2), IL-6, IL-8, IL-1beta, and TNF-alpha mRNA. Postexercise increases in plasma cytokines did not differ between groups, but the pattern of change over the 3-day exercise period tended to be lower in Q vs. P for IL-8 and TNF-alpha (P = 0.094 for both). mRNA increased significantly postexercise for each cytokine measured in blood leukocyte and muscle samples. Leukocyte IL-8 and IL-10 mRNA were significantly reduced in Q vs. P (interaction effects, P = 0.019 and 0.012, respectively) with no other leukocyte or muscle mRNA group differences. Muscle NF-kappaB did not increase postexercise and did not differ between Q and P. Muscle COX-2 mRNA increased significantly postexercise but did not differ between Q and P. In summary, 1 g/day quercetin supplementation by trained cyclists over a 24-day period diminished postexercise expression of leukocyte IL-8 and IL-10 mRNA, indicating that elevated plasma quercetin levels exerted some effects within the blood compartment. Quercetin did not, however, influence any of the muscle measures, including NF-kappaB content, cytokine mRNA, or COX-2 mRNA expression across a 3-day intensified exercise period.
Nieman
David C
DC
Department of Health, Leisure, and Exercise Science, PO Box 32071, Appalachian State Univ., Boone, NC 28608, USA. niemandc@appstate.edu
Henson
Dru A
DA
Davis
J Mark
JM
Angela Murphy
E
E
Jenkins
David P
DP
Gross
Sarah J
SJ
Carmichael
Martin D
MD
Quindry
John C
JC
Dumke
Charles L
CL
Utter
Alan C
AC
McAnulty
Steven R
SR
McAnulty
Lisa S
LS
Triplett
N Travis
NT
Mayer
Eugene P
EP
D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D018932:Chemokine CCL2 / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000378:metabolism; D016207:Cytokines / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology*; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein / Q000378:metabolism; D007378:Interleukins / Q000378:metabolism; D007962:Leukocytes / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D011794:Quercetin / Q000494:pharmacology*; D012333:RNA, Messenger / Q000097:blood / Q000378:metabolism*; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D000893:Anti-Inflammatory Agents; C111835:CCL2 protein, human; D018932:Chemokine CCL2; D016207:Cytokines; D053590:Interleukin 1 Receptor Antagonist Protein; D007378:Interleukins; D016328:NF-kappa B; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D011794:Quercetin; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human