Evaluation of oxidative stress in tic disorders

Aim and hypothesis: Though tic disorders is one of the most common neurodevelopmental disorders in childhood, limited information about the etiology and pathophysiology of tic disorders increases the interest in the disorder. Many factors such as genetic, environmental and biochemical factors play a role in the etiopathogenesis of tic disorders.Few studies have been conducted on the biochemical causes of Tic Disorders.The aim of this study is to examine the relationship between oxidative stress parameters and tic disorders. Method: According to DSM-IV TR diagnostic criteria, 27 patients between the ages of 6-17 who had diagnosed tic disorder and had no additional psychiatric and chronic physical illness and age and sex matched 27 healthy volunteers were included in the study. Sociodemographic data form, Schedule for Affective Disorders and Schizophrenia for School-Age Children--Present and Lifetime Version (K-SADS-PL) and Yale Global Tic Severity Scale (YGTSS) were applied to the case group and sociodemographic data form andSchedule for Affective Disorders and Schizophrenia for School-Age Children--Present and Lifetime Version (K-SADS-PL) were applied to healthy volunteers. Malondialdehyde (MDA) and nitric oxide (NO) which are oxidative stress markers levels and superoxide dismutase-1 (SOD-1), glutathione peroxidase-1 (GPx-1), paraoxonase-1 (PON-1) and thiol which are antioxidant molecules levels were investigated in serum samples of blood samples taken from cases and healthy volunteers . The relationship between oxidative stress and disease severity, and differences between the groups oxidative stress level were examined. Results: One of the oxidative stress parameters, NO levels were significantly higher in the tic disorder group (including subgroups, Tourette syndrome and chronic motor tic disorder) than in the control group. Lipid peroxidation indicator, MDA although levels it was not statistically significant, it was found higher in the tic disorder group than in the control group. There was no significant difference between groups in antioxidant markers SOD-1, GPx, PON-1 and thiol levels. There was no significant relationship between oxidative stress parameters and disease severity. Conclusion: This is the first study to examine oxidative stress in tic disorder. This study supports the presence of oxidative stress due to high levels of oxidant and antioxidant parameters in children and adolescents with tic disorder. Key words: Tic disorder, child and adolescent, oxidative stress.