8-hydroxy-2--deoxyguanosine and Attention-Deficit-Disorder-with-Hyperactivity

Bisphenol A (BPA) is an endocrine-disrupting chemical. Studies have shown that the exposure to BPA is associated with attention-deficit/hyperactivity disorder (ADHD) during adolescent development. However the direct clinical evidence is limited. To investigate the possible association between environmental BPA exposure and the altered behavior of children, a case-control study was conducted with children aged 6-12 years in Guangzhou, China. Two hundred fifteen children diagnosed with ADHD and 253 healthy children from Guangzhou were recruited as the case and control groups, respectively. Urinary BPA and 8-hydroxy-2'-deoxyguanosine (8-OHdG, a biomarker of oxidative DNA damage) concentrations were determined by high-performance liquid chromatography/tandem spectrometry. The results showed that concentrations of urinary BPA for the case group were significantly higher than those for the control group (3.44 vs 1.70 μg/L; 4.63 vs 1.71 μg/g Crt. p < .001). A stepwise increase in the odds ratios for ADHD was observed with the increasing quartiles of children's urinary BPA (first quartile: reference category; second quartile adjusted OR: 1.79, 95% CI: 0.95-3.37; third quartile adjusted OR: 7.44, 95% CI: 3.91-14.1; fourth quartile adjusted OR: 9.41, 95% CI: 4.91-18.1). When the BPA levels were stratified by gender, the odds of ADHD among boys and girls increased significantly with urinary BPA concentrations (adjusted OR: 4.58, 95% CI: 2.84-7.37; adjusted OR: 2.83, 95% CI: 1.17-6.84). Urinary 8-OHdG concentrations in the ADHD children were significantly higher than those in the control group. Furthermore, the linear regression analysis results indicated that a significant relationship existed between BPA exposure and 8-OHdG levels (R = 0.257, p < .001). Our findings provide direct evidence that childhood BPA exposure may be related to ADHD and 8-OHdG concentrations for children. Moreover, BPA exposure could increase the higher occurrence of ADHD for boy than for girls.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Attention Deficit Disorder with Hyperactivity; Benzhydryl Compounds; Biomarkers; Case-Control Studies; Child; China; Chromatography, High Pressure Liquid; Deoxyguanosine; DNA Damage; Endocrine Disruptors; Environmental Exposure; Female; Humans; Male; Oxidation-Reduction; Phenols; Schools

The aim of this study was to investigate oxidative stress in ADHD children.. Levels of oxidant parameters malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OHDG), advanced oxidation protein products (AOPP) and antioxidant parameters paraoxonase (PON1) and thiol levels were measured in thirty children with ADHD (27 boys, 3 girls) who were firstly diagnosed according to DSM-IV and thirty healthy children (18 boys, 12 girls) aged 6-12 years.. The levels of the oxidant parameters MDA and 8-OHDG were statistically significantly lower in ADHD children compared to the controls. We did not find a significant difference between the groups regarding AOPP, PON1, and thiol levels.. We found low levels of some oxidants and no difference of antioxidant parameters in ADHD children. Our study points out that there may not be a direct relationship between oxidative stress and ADHD.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aryldialkylphosphatase; Attention Deficit Disorder with Hyperactivity; Blood Proteins; Child; Chromatography, High Pressure Liquid; Deoxyguanosine; Diagnostic and Statistical Manual of Mental Disorders; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Malondialdehyde; Oxidative Stress; Sulfhydryl Compounds; Surveys and Questionnaires