title: The effect of carbohydrate ingestion on plasma interleukin-6, hepcidin and iron concentrations following prolonged exercise.
abstract: The aim of our study was twofold, firstly to examine the relationship between plasma concentrations of IL-6, hepcidin and iron following prolonged exercise and secondly, to assess the effect of carbohydrate ingestion on circulating hepcidin concentration post-exercise. The study was a randomised double-blind cross-over design, with participants consuming either a carbohydrate (CHO) or an isovolumetric placebo drink throughout the trial. Nine healthy, trained males completed a treadmill run at 60% vVO(2max) for 120 min followed by a 5 km time trial. Plasma concentrations of both IL-6 and hepcidin significantly increased post-exercise following both trials (p<.05) and returned to baseline by 24 h post (p>.05). A positive correlation between hepcidin and IL-6 was demonstrated immediately following exercise during PLA while there was a trend for a moderate correlation during CHO (PLA trial rho=0.81, p<0.001; CHO trial rho=0.36, p=0.07). Plasma iron was unaffected immediately post-exercise but significantly reduced by 24 h post-exercise compared to baseline. CHO ingestion significantly reduced post-exercise IL-6 (p<.05) but this had no effect on plasma hepcidin or iron concentration. Our data demonstrate CHO supplementation does not alter the rapid hepcidin response associated with exercise and does not prevent a subsequent fall in plasma iron concentration. This finding adds further support to the theory that an exercise-induced, up-regulation of hepcidin activity is a mechanism causing iron deficiency in endurance athletes.
authors.affiliation: Department of Sport and Exercise Science, Northumbria University, Newcastle, UK. Paula.ansley@unn.ac.uk
authors.forename: Paula
authors.initials: P
authors.lastname: Robson-Ansley
authors.forename: Ian
authors.initials: I
authors.lastname: Walshe
authors.forename: Douglas
authors.initials: D
authors.lastname: Ward
mesh_terms: D000328:Adult; D023181:Antimicrobial Cationic Peptides / Q000097:blood*; D002241:Carbohydrates / Q000008:administration & dosage* / Q000494:pharmacology*; D015444:Exercise / Q000502:physiology*; D005247:Feeding Behavior / Q000187:drug effects*; D064451:Hepcidins; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D007501:Iron / Q000097:blood*; D008297:Male; D010919:Placebos
chemical_list: D023181:Antimicrobial Cationic Peptides; D002241:Carbohydrates; C578702:HAMP protein, human; D064451:Hepcidins; C508600:IL6 protein, human; D015850:Interleukin-6; D010919:Placebos; D007501:Iron