Oxidative stress in chronic headaches: old and new markers

Abstract

Andrea Bolner, Giovanni D

Objective: To study the effects of free radicals’ overproduction in chronic primary headaches, we have evaluated two oxidative stress biomarkers, 3-nitrotyrosine (3-NT) and 8-hydroxy-deoxyguanosine expressed as ratio vs 2-deoxyguanosine (8-OHdG/2-dG). Methods: Analyses were done in plasma of three groups of subjects: chronic migraine (CM), chronic tension-type headache (CTTH) and healthy controls (CNT). 3-NT was analyzed by ultraviolet high-performance liquid chromatography (HPLC-UV), and 8-OHdG and 2-dG by two similar HPLC methods with electrochemical and fluorimetric detection, respectively. Results: In comparison to CNT group, 3-NT levels in plasma were significantly higher in CM patients whereas in CTTH were in the same range of healthy subjects. Instead, the mean 8-OHdG/2-dG ratios were higher in both chronic headache groups than CNT but without statistical significance (P values 0.46 and 0.1 for CTTH and CM, respectively). Conclusion: The higher mean plasmatic levels of 3-NT in CM only, suggest that just in this type of migraine an anomalous production of reactive nitrogen species occurs.