Cytokine mRNA expression responses to resistance, aerobic, and concurrent exercise in sedentary middle-aged men

Appl Physiol Nutr Metab. 2014 Feb;39(2):130-7. doi: 10.1139/apnm-2013-0076. Epub 2013 Jul 26.

Abstract

Concurrent resistance and aerobic exercise (CE) is recommended to ageing populations, though is postulated to induce diminished acute molecular responses. Given that contraction-induced cytokine mRNA expression reportedly mediates remunerative postexercise molecular responses, it is necessary to determine whether cytokine mRNA expression may be diminished after CE. Eight middle-aged men (age, 53.3 ±1.8 years; body mass index, 29.4 ± 1.4 kg·m(-2)) randomly completed (balanced for completion order) 8 × 8 leg extensions at 70% maximal strength (RE), 40 min of cycling at 55% of peak aerobic workload (AE), or (workload-matched) 50% RE and 50% AE (CE). Muscle (vastus lateralis) was obtained pre-exercise, and at 1 h and 4 h postexercise, and analyzed for changes of glycogen concentration, tumor necrosis factor (TNF)α, TNF receptor-1 and -2 (TNF-R1 and TNF-R2, respectively), interleukin (IL)-6, IL-6R, IL-1β, and IL-1 receptor-antagonist (IL-1ra). All exercise modes upregulated cytokine mRNA expression at 1 h postexercise comparably (TNFα, TNF-R1, TNF-R2, IL-1β, IL-6) (p < 0.05). Expression remained elevated at 4 h after RE and AE (p < 0.05), though returned to pre-exercise levels after CE (p > 0.05). Moreover, AE and RE upregulated IL-1β and IL-1ra expression, whereas CE upregulated IL-1β expression only (p < 0.05). Only AE reduced muscle glycogen concentration (p < 0.05), whilst upregulating receptor expression the greatest; though, IL-6R expression remained unchanged after all modes (p > 0.05). In conclusion, in middle-aged men, all modes induced commensurate cytokine mRNA expression at 1 h postexercise; however, only CE resulted in ameliorated expression at 4 h postexercise. Whether the RE or AE components of CE are independently or cumulatively sufficient to upregulate cytokine responses, or whether they collectively inhibit cytokine mRNA expression, remains to be determined.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Cytokines / genetics*
  • Exercise / physiology*
  • Humans
  • Male
  • Middle Aged
  • RNA, Messenger / biosynthesis*
  • Resistance Training
  • Sedentary Behavior*

Substances

  • Cytokines
  • RNA, Messenger