title: Quercetin ingestion does not alter cytokine changes in athletes competing in the Western States Endurance Run.
abstract: The purpose of this study was to measure the influence of quercetin on plasma cytokines, leukocyte cytokine mRNA, and related variables in ultramarathoners competing in the 160-km Western States Endurance Run (WSER). Sixty-three runners were randomized to quercetin and placebo groups and under double-blinded methods ingested 1000 mg/day quercetin for 3 weeks before the WSER. Thirty-nine of the 63 subjects (n = 18 for quercetin, n = 21 for placebo) finished the race and provided blood samples the morning before the race and 15-30 min postrace. Significant prerace to postrace WSER increases were measured for nine proinflammatory and anti-inflammatory plasma cytokines, cortisol (quercetin = 94%, placebo = 96%), serum C-reactive protein (CRP) (mean +/- SE absolute increase, quercetin = 31.8 +/- 4.2, placebo = 38.2 +/- 5.0 mg/L), and creatine kinase (CK) (quercetin = 21,575 +/- 3,977, placebo = 19,455 +/- 3,969 U/L), with no significant group differences. Interleukin-6 (IL-6) mRNA did not change post-WSER, with a significant decrease measured for leukocyte IL-8 mRNA (0.21 +/- 0.03-fold and 0.25 +/- 0.04-fold change from rest, quercetin and placebo, respectively) and significant increases for IL-1Ra mRNA (1.43 +/- 0.18-fold and 1.40 +/- 0.16-fold change, quercetin and placebo, respectively) and IL-10 mRNA (12.9 +/- 3.9-fold and 17.2 +/- 6.1-fold change, quercetin and placebo, respectively), with no significant differences between groups. In conclusion, quercetin ingestion (1 g/day) by ultramarathon athletes for 3 weeks before a competitive 160-km race significantly increased plasma quercetin levels but failed to attenuate muscle damage, inflammation, increases in plasma cytokine and hormone levels, and alterations in leukocyte cytokine mRNA expression.
authors.affiliation: Department of Biology, Health, Leisure, and Exercise Science, Fischer Hamilton/Nycom Biochemistry Laboratory, Appalachian State University, Boone, North Carolina. 28608, USA. niemandc@appstate.edu
authors.forename: David C
authors.initials: DC
authors.lastname: Nieman
authors.forename: Dru A
authors.initials: DA
authors.lastname: Henson
authors.forename: J Mark
authors.initials: JM
authors.lastname: Davis
authors.forename: Charles L
authors.initials: CL
authors.lastname: Dumke
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Gross
authors.forename: D Paul
authors.initials: DP
authors.lastname: Jenkins
authors.forename: E Angela
authors.initials: EA
authors.lastname: Murphy
authors.forename: Martin D
authors.initials: MD
authors.lastname: Carmichael
authors.forename: John C
authors.initials: JC
authors.lastname: Quindry
authors.forename: Steven R
authors.initials: SR
authors.lastname: McAnulty
authors.forename: Lisa S
authors.initials: LS
authors.lastname: McAnulty
authors.forename: Alan C
authors.initials: AC
authors.lastname: Utter
authors.forename: Eugene P
authors.initials: EP
authors.lastname: Mayer
mesh_terms: D000328:Adult; D016207:Cytokines / Q000097:blood* / Q000235:genetics; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010807:Physical Endurance; D011794:Quercetin / Q000008:administration & dosage* / Q000032:analysis / Q000097:blood; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012420:Running
chemical_list: D016207:Cytokines; D012333:RNA, Messenger; D011794:Quercetin