Decreased integrity of exercise-induced plasma cell free nuclear DNA - negative association with the increased oxidants production by circulating phagocytes

Stawski, R.; Walczak, K.; Perdas, E.; Włodarczyk, A.; Sarniak, A.; Kosielski, P.; Meissner, P.; Budlewski, T.; Padula, G.; Nowak, D.

doi:10.1101/432237

bioRxiv · 10.1101/432237

Decreased integrity of exercise-induced plasma cell free nuclear DNA - negative association with the increased oxidants production by circulating phagocytes

Stawski, R.·Walczak, K.·Perdas, E.·Włodarczyk, A.·Sarniak, A.·Kosielski, P.·Meissner, P.·Budlewski, T.·Padula, G.·Nowak, D.

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Abstract

Strenuous exercise increases circulating cell free DNA (cf DNA) and stimulates blood phagocytes to generate reactive oxygen species (ROS) which may induce DNA strand breaks. We tested whether: (A) elevated cf DNA in response to three repeated bouts of exhaustive exercise has decreased integrity; (B) each bout of exercise increases luminol enhanced whole blood chemiluminescence (LBCL) as a measure of ROS production by polymorphonuclear leukocytes. Eleven men performed three treadmill exercise tests to exhaustion separated by 72 hours of resting. Pre- and post-exercise concentrations and integrity of cf nuclear and mitochondrial DNA (cf n-DNA, cf mt-DNA) and resting and fMLP-stimulated LBCL were determined. Each bout increased concentrations of cf n-DNA by more than 10-times which was accompanied by about 2-times elevated post-exercise rLBCL and fMLP-LBCL. Post-exercise cf n-DNA integrity (integrity index, I206/78) decreased after the first (0.59{+/-}0.19 vs. 0.48{+/-}0.18) and second (0.53{+/-}0.14 vs. 0.44{+/-}0.17) bout of exercise. There were negative correlations between I206/78 and rLBCL (=-0.37) and I206/78 and fMLP-LBCL (=- 0.40) - analysis of pooled pre- and post-exercise data (n=66). cf-mt DNA integrity (I218/97) did not alter in response to exercise. This suggests an involvement of phagocyte ROS in cf n-DNA strand breaks in response to exhaustive exercise.

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Stawski, R., Walczak, K., Perdas, E., Włodarczyk, A., Sarniak, A., Kosielski, P., Meissner, P., Budlewski, T., Padula, G., Nowak, D.. 2018-10-01. Decreased integrity of exercise-induced plasma cell free nuclear DNA - negative association with the increased oxidants production by circulating phagocytes. https://doi.org/10.1101/432237

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