Elevated serum S100B levels in medication naïve children and adolescents with obsessive-compulsive disorder.

PURPOSE: Obsessive-compulsive disorder (OCD) is a condition characterized by obsessions and/or compulsions. S100B protein is shown to be involved in microglial activation besides intracellular signaling, intercellular communication and cell growth. The relation between S100B protein and various psychiatric disorders except OCD has been studied so far. This study aimed to analyze serum S100B levels for the first time in medication naive OCD diagnosed children and adolescents and to compare them with the control group. MATERIALS AND METHODS: Peripheral blood S100B levels of 27 children and adolescents with OCD were compared to 27 control group subjects to assess any possible association between OCD and S100B levels. All the children and adolescents completed the child version of the Obsessive-Compulsive Inventory (OCI - CV). RESULTS: Compared to control group, higher serum S100B levels were found in OCD group (z = -2.258, p = 0.024). We also found that obsessing and washing subscales' scores and total score of OCI - CV were statistically significantly correlated with S100B levels (respectively, r = .292, p = 0.032; r = .306, p = 0.025; r = .296, p = 0.030). CONCLUSIONS: The present study's findings are in accord with previous studies demonstrating the significance of S100B protein in other psychiatric disorders and suggesting a relation in children and adolescents with OCD for the first time. The role of S100B protein in OCD etiology and pathogenesis should be evaluated further.

Altered microRNA 5692b and microRNA let-7d expression levels in children and adolescents with attention deficit hyperactivity disorder.

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder. Its etiology is not clearly understood yet, but neurobiological, genetic and environmental factors are shown to play a role. The relationship between ADHD and miRNAs has been studied quite recently, and few studies have been conducted up to now. In this study, peripheral blood expression levels of miR-5692b, miR-let-7d, miR-124-3p, miR-4447 and miR-107 of 30 children and adolescents with combined type ADHD were compared to 30 healthy controls to understand the roles of these miRNAs in the ADHD etiopathogenesis. Compared to controls, levels of miR-5692b (p = 0.006) were found higher and levels of miR-let-7d (p = 0.017) were found lower in the ADHD group. There was no significant difference in terms of miR-124-3p, miR-4447, and miR-107 levels between the groups. In conclusion, our findings support other studies suggesting the importance of miRNAs in the pathogenesis of ADHD. Regarding the regulatory role of miRNAs in gene regulation, their contribution to etiopathogenesis and heterogeneity of ADHD should be investigated further.