title: The response of interleukin-6 and soluble interleukin-6 receptor isoforms following intermittent high intensity and continuous moderate intensity cycling.
abstract: As interleukin-6 (IL-6), its soluble receptor (sIL-6R), and the IL-6/sIL-6R complex is transiently elevated in response to prolonged moderate-intensity exercise, this study investigated how these levels would be modulated by an acute bout of high-intensity intermittent (HIIT) exercise in comparison to continuous moderate-intensity exercise (MOD). This study also investigated the expression of the differentially spliced sIL-6R (DS-sIL-6R) in response to exercise. Eleven healthy males completed two exercise trials matched for external work done (582 ± 82 kJ). During MOD, participants cycled at 61.8 (2.6)% VO(2peak) for 58.7 (1.9) min, while HIIT consisted of ten 4-min intervals cycling at 87.5 (3.4)% [Formula: see text] separated by 2-min rest. Blood samples were collected pre-exercise, post-exercise, and 1.5, 6, and 23 h post-exercise. Plasma IL-6, sIL-6R, IL-6/sIL-6R complex, and DS-sIL-6R levels were measured by enzyme-linked immunosorbent assay. HIIT caused a significantly greater increase in IL-6 than MOD (P = 0.018). Both MOD and HIIT resulted in an increase in sIL-6R and IL-6/sIL-6R complex (P < 0.001), however, this was not significantly different between trials. Soluble IL-6R peaked at 6 h post-exercise in both trials. DS-sIL-6R increased significantly with exercise (P = 0.02), representing 0.49% of the total sIL-6R increase. This investigation has demonstrated that the IL-6 response is greater after intermittent high-intensity exercise than comparable moderate-intensity exercise; however, increased IL-6/sIL-6R complex nor sIL-6R was different between HIIT and MOD. The current study has shown for the first time that elevated sIL-6R after HIIT exercise is derived from both proteolytic cleavage and differential splicing.
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, Ashby Road, Loughborough, Leicestershire, LE11 3TU, UK.
authors.forename: Melanie
authors.initials: M
authors.lastname: Leggate
authors.forename: Mari A
authors.initials: MA
authors.lastname: Nowell
authors.forename: Simon A
authors.initials: SA
authors.lastname: Jones
authors.forename: Myra A
authors.initials: MA
authors.lastname: Nimmo
mesh_terms: D000328:Adult; D004797:Enzyme-Linked Immunosorbent Assay; D015444:Exercise; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D020033:Protein Isoforms / Q000097:blood; D019947:Receptors, Interleukin-6 / Q000097:blood*; D055815:Young Adult
chemical_list: D015850:Interleukin-6; D020033:Protein Isoforms; D019947:Receptors, Interleukin-6
references.citation: J Appl Physiol (1985). 2009 Oct;107(4):1006-14
references.pmid: 19696361
references.citation: J Strength Cond Res. 2009 Jan;23(1):225-30
references.pmid: 19057403
references.citation: Sports Med. 2002;32(1):53-73
references.pmid: 11772161
references.citation: J Immunol. 2004 May 1;172(9):5676-83
references.pmid: 15100312
references.citation: Eur J Appl Physiol. 2000 Dec;83(6):512-5
references.pmid: 11192058
references.citation: Exerc Immunol Rev. 2006;12:6-33
references.pmid: 17201070
references.citation: J Exp Med. 1996 Apr 1;183(4):1399-406
references.pmid: 8666898
references.citation: Immunology. 1998 Nov;95(3):360-9
references.pmid: 9824498
references.citation: J Appl Physiol. 1974 Aug;37(2):247-8
references.pmid: 4850854
references.citation: Am J Cardiol. 2006 Jan 1;97(1):141-7
references.pmid: 16377300
references.citation: J Physiol. 2001 Oct 15;536(Pt 2):329-37
references.pmid: 11600669
references.citation: Med Sci Sports Exerc. 2003 Feb;35(2):263-9
references.pmid: 12569215
references.citation: Biochem J. 1994 Jun 1;300 ( Pt 2):281-90
references.pmid: 8002928
references.citation: J Immunol. 2003 Sep 15;171(6):3202-9
references.pmid: 12960349
references.citation: Cell Stress Chaperones. 2008 Summer;13(2):247-51
references.pmid: 18320358
references.citation: FASEB J. 2001 Jan;15(1):43-58
references.pmid: 11149892
references.citation: Sports Med. 1998 Aug;26(2):101-17
references.pmid: 9777683
references.citation: Cell. 1989 Aug 11;58(3):573-81
references.pmid: 2788034
references.citation: J Physiol. 2003 Jan 1;546(Pt 1):299-305
references.pmid: 12509497
references.citation: J Appl Physiol (1985). 2009 Jul;107(1):63-8
references.pmid: 19423836
references.citation: FASEB J. 2006 Oct;20(12):2174-6
references.pmid: 16912152
references.citation: FASEB J. 2005 Jul;19(9):1181-3
references.pmid: 15837717
references.citation: J Exp Med. 1999 Feb 1;189(3):599-604
references.pmid: 9927522
references.citation: Cytokine. 2009 Aug;47(2):98-102
references.pmid: 19527938
references.citation: Cytokine. 2009 Feb;45(2):111-6
references.pmid: 19097916
references.citation: FASEB J. 2001 Dec;15(14):2748-50
references.pmid: 11687509
references.citation: J Immunol. 1994 May 15;152(10):4958-68
references.pmid: 8176214
references.citation: J Physiol. 2001 Dec 1;537(Pt 2):633-9
references.pmid: 11731593
references.citation: Eur J Immunol. 1994 Aug;24(8):1945-8
references.pmid: 8056053
references.citation: J Appl Physiol (1985). 2007 Apr;102(4):1439-47
references.pmid: 17170203
references.citation: FASEB J. 2003 Nov;17(14):2166-8
references.pmid: 12958150
references.citation: BMC Endocr Disord. 2009 Jan 28;9:3
references.pmid: 19175906