Plasma levels of interleukin-6 and interleukin-18 after an acute physical exercise: relation with post-exercise energy intake in twins.
Increased interleukin-6 (IL-6) plasma levels have been described to occur during physical exercise. A relative reduction in energy intake after physical activity has also been reported after exercise, indicating a possible involvement of IL-6 as an anorexigenic factor. Given the possible effect of interleukins on appetite, we assessed whether a controlled physical activity bout is related with changes in IL-6, IL-6 soluble receptor (IL-6sR), gp130 and interleukin-18 (IL-18) plasma levels, as well as their relation with post-exercise energy intake. A co-twin intervention study was carried out with five young male monozygotic twin pairs. One co-twin performed 45 min of submaximal exercise on a treadmill near the anaerobic threshold ending with 7 min at 90 % VO(2) max, while his co-twin remained non-active. Ad libitum energy intake was tested through a carbohydrate-rich meal test. Venous blood samples were drawn at baseline, immediately after exercise and after the meal ingestion. Plasma concentrations of IL-6, IL-6sR, gp130 and IL-18 were measured via ELISA. IL-6 plasma levels increased after physical activity bout (2.6-fold change; p = 0.04). A less marked trend, although still significant, was observed for plasma levels of IL-6sR and gp130. Plasma levels of IL-18 did not significantly change during exercise. The twins who exercised exhibited significantly lower energy intake (181 versus 1,195 kcal; p = 0.04), compared to the co-twins who remained resting. The present study in monozygotic twins shows increased IL-6 plasma levels after acute physical exercise with a significant reduction in energy intake, supporting a linkage between IL-6 and acute post-exercise eating behaviour.
Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile.
C
C
Almada
L R
LR
Cataldo
S V
SV
Smalley
E
E
Diaz
A
A
Serrano
M I
MI
Hodgson
J L
JL
Santos
D000293:Adolescent; D001066:Appetite / Q000502:physiology; D050822:Cytokine Receptor gp130 / Q000097:blood; D002149:Energy Intake; D015444:Exercise / Q000502:physiology*; D005247:Feeding Behavior; D006801:Humans; D020382:Interleukin-18 / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D019947:Receptors, Interleukin-6 / Q000097:blood; D012995:Solubility; D014430:Twins, Monozygotic; D055815:Young Adult
C508600:IL6 protein, human; D020382:Interleukin-18; D015850:Interleukin-6; D019947:Receptors, Interleukin-6; D050822:Cytokine Receptor gp130