title: Circadian rhythmometry of serum interleukin-2, interleukin-10, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor in men.
abstract: Serum levels of four cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-10 (IL-10)] were measured in nine diurnally active healthy adult male subjects at 3-h intervals during a 24-h period. Statistical evaluation by analysis of variance and/or the least- squares fit of a cosine model revealed significant 24-h rhythms for each cytokine. Although the amount of IL-2 in the serum was low, the levels fluctuated to form a single peak at approximately noon. In contrast, the other three cytokines exhibited a biphasic temporal pattern. In subjects with detectable TNF-alpha levels, the first peak occurred at 07:30 and the second at 13:30. IL-10 levels also exhibited a biphasic pattern, with one peak at 07:30 and the second 12 h later at 19:30. GM-CSF levels were last to rise, first peaking at approximately 13:30 and then again at 19:30. These results suggest temporal patterns that are unique for each cytokine, generally with daytime highs and nighttime lows.
authors.affiliation: Research Service, Hines V.A. Hospital, Illinois 60141, USA.
authors.forename: M R
authors.initials: MR
authors.lastname: Young
authors.forename: J P
authors.initials: JP
authors.lastname: Matthews
authors.forename: E L
authors.initials: EL
authors.lastname: Kanabrocki
authors.forename: R B
authors.initials: RB
authors.lastname: Sothern
authors.forename: B
authors.initials: B
authors.lastname: Roitman-Johnson
authors.forename: L E
authors.initials: LE
authors.lastname: Scheving
mesh_terms: D000368:Aged; D002940:Circadian Rhythm / Q000502:physiology*; D016207:Cytokines / Q000097:blood*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000097:blood / Q000502:physiology; D006801:Humans; D016753:Interleukin-10 / Q000097:blood / Q000502:physiology; D007376:Interleukin-2 / Q000097:blood / Q000502:physiology; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology*
chemical_list: D016207:Cytokines; D007376:Interleukin-2; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D016178:Granulocyte-Macrophage Colony-Stimulating Factor