Monitoring changes in thioredoxin and over-oxidised peroxiredoxin in response to exercise in humans

Abstract

Introduction. Peroxiredoxin (PRDX) and thioredoxin (TRX) are antioxidant proteins that control cellular signalling and redox balance, although their response to exercise is unknown. This study aimed to assess key aspects of the PRDX–TRX redox cycle in response to three different modes of exercise. Methods. Healthy males (n = 10, mean ± SD: 22 ± 3 yrs) undertook three exercise trials on separate days: two steady-state cycling trials at moderate (60% O_2MAX; 27 min, MOD) and high (80% O_2MAX; 20 min, HIGH) intensities, and a low-volume high-intensity interval training trial (10 × 1 min 90% O_2MAX, LV-HIIT). Peripheral blood mononuclear cells were assessed for TRX-1 and over-oxidised PRDX (isoforms I–IV) protein expression before, during, and 30 min following exercise (post + 30). The activities of TRX reductase (TRX-R) and the nuclear factor kappa B (NF-κB) p65 subunit were also assessed. Results. TRX-1 increased during exercise in all trials (MOD, + 84.5%; HIGH, + 64.1%; LV-HIIT, + 205.7%; p < 05), whereas over-oxidised PRDX increased during HIGH only (MOD, − 28.7%; HIGH, + 202.9%; LV-HIIT, − 22.7%; p < .05). TRX-R and NF-κB p65 activity increased during exercise in all trials, with the greatest response in TRX-R activity seen in HIGH (p < 0.05). Discussion. All trials stimulated a transient increase in TRX-1 protein expression during exercise. Only HIGH induced a transient over-oxidation of PRDX, alongside the greatest change in TRX-R activity. Future studies are needed to clarify the significance of heightened peroxide exposure during continuous high-intensity exercise and the mechanisms of PRDX-regulatory control.

Keywords::

• Redox status
• cytokines
• antioxidant
• inflammation
• exercise

Acknowledgements

Dr Alex Wadley, Dr Sarah Aldred, Dr James Fisher and Dr Pam Chen were involved in the conception and design of the experiments and data collection. Data analysis, interpretation and drafting the article for important intellectual content were undertaken by all authors.

Funding

University of Birmingham UK.

Declaration of interest

The authors report no declarations of interest. The authors alone are responsible for the content and writing of the paper.

Supplementary material available online

Supplementary Figure 1 and Table I to be found at online http://informahealthcare.com/doi/abs/10.3109/10715762.2014.1000890.