A quantitative method to monitor short and long-term Reactive Oxygen Species (ROS) production kinetics in humans by Electron Paramagnetic Resonance (EPR)

EPR was recently adopted to develop a physiological relevant method for rapid and noninvasive ROS concentration measurement in fresh human peripheral blood1. This innovative approach that showed an increase of ROS levels in short-term high-intensity exercise, is here applied to monitor short and long term kinetics. Methods: A bench top continuous wave instrument (Bruker) operating in the X-Band region (~ 9 GHz) dealing with very low ROS levels in 50μl samples was used. Results With respect to basal, ROS levels were found to: A) Short term kinetics a) increase after exercise in: healthy young (20±1yr; +7%; p<0.05), elder (73±5 yr; +8%; p<0.05) and sporadic Amyotrophic Lateral Sclerosis (sALS) patients (57±11yr; +7-19% range); b) decrease after 1 h antioxidant (R(+) Thioctic acid) administration in: healthy subjects (49±5yr; -7.5 % p<0.05); patients (type II Diabetic Neuropathies) (65±3yr; -7% p<0.05; B) Long term kinetics: a) increase in sALS ( 6 months +10% p<0.05) b) decrease in training (32±5yr; -20%; p<0.001) subjects and 1 month antioxidant administration in healthy (-8%; p<0.05) and diabetic neuropathies (-8%; p<0.05). The results were confirmed by a positive statistical correlation with traditional oxidative stress damagemarkers: Protein Carbonyls (PC) and Thiobarbituric acid reactive substances (TBARS). Conclusions: The method is suitable to quantitatively aestimate oxidative stress kinetic response. 1. Mrakic-Sposta S. et al, Oxid Med Cell Longev. 2012;2012:973927.