Melatonin supplementation improves oxidative and inflammatory state in the blood of professional athletes during the preparatory period for competitions

Abstract

Melatonin supplementation has been proved to have antioxidant and anti-inflammatory effects in humans. The aim of the study was to estimate the influence of a 30-day melatonin supplementation on oxidative and inflammatory state in the blood of intense training professional athletes. The study was conducted in 47 football players, 19 rowers, and 15 adults who did not practice sports (control group). Blood samples were taken once from the control group and twice from the athletes: before and after 30-day melatonin administration (5 mg daily before sleep). Serum levels of melatonin, isoprostanes, antiox-LDL antibodies, interleukin-6, and C-reactive protein were measured. In erythrocytes, the concentrations of reduced glutathione (GSH) and malondialdehyde (MDA), and the activities of glutathione peroxidase (GSH-Px), cytoplasmic superoxide dismutase (SOD-1), and glutathione reductase (GR) were determined. Melatonin supplementation caused a significant decrease in markers of oxidative stress and a significant increase in melatonin concentration and the activities of SOD-1 and GSH-Px in athletes. The obtained data showed increased oxidative stress and inflammatory processes in professional athletes during intense training and indicated that supplementation of melatonin in their daily diet may have a beneficial effect on the protection of tissues against the adverse action of RONS and inflammatory processes.

Keywords:

• Antioxidant defense
• athletes
• inflammatory processes
• melatonin supplementation
• oxidative stress

Acknowledgements

All the authors contributed to this manuscript. Conceptualization, Jolanta Czuczejko, Karolina Szewczyk-Golec, Łukasz Sielski, Alina Woźniak, Bartosz Woźniak; Methodology, Jolanta Czuczejko, Karolina Szewczyk-Golec, Łukasz Sielski; validation, Jolanta Czuczejko and Karolina Szewczyk-Golec; formal analysis, Jolanta Czuczejko, Karolina Szewczyk-Golec, Łukasz Sielski, Alina Woźniak, Bartosz Woźniak; investigation, Jolanta Czuczejko, Łukasz Sielski, Karolina Szewczyk-Golec; resources, Jolanta Czuczejko; data curation, Jolanta Czuczejko; writing – original draft preparation, Jolanta Czuczejko, Karolina Szewczyk-Golec, Łukasz Sielski; writing – review & editing, Karolina Szewczyk-Golec and Łukasz Sielski; visualization, Karolina Szewczyk-Golec; supervision, Karolina Szewczyk-Golec; Project Administration, Jolanta Czuczejko; funding acquisition, Jolanta Czuczejko. All authors have read and approved the final paper.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the University of Nicolaus Copernicus, Toruń, Poland [grant number 01/CM/2012[. The results of the study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation, and statement that results of the present study do not constitute endorsement by ACSM.