ABSTRACT
OBJECTIVE: Frontiers between pediatric bipolar disorder (PBD) and attention-deficit/hyperactivity disorder (ADHD) are not well defined. Few studies have addressed potentially different neurobiological factors between the two disorders. Brain-derived neurotrophic factor (BDNF) has been increasingly recognized for its etiologic and prognostic role in adult bipolar disorder (BD) studies. This study aimed to examine the BDNF gene polymorphism and potential alterations in BDNF serum levels in the pediatric ADHD patients with or without comorbid BD illness. METHOD: We assessed the non-synonymous single-nucleotide polymorphism in the BDNF gene (rs6265/Val66Met) and its serum levels in children and adolescents with BD comorbid with ADHD (BD + ADHD) and ADHD alone. Children and adolescents were assessed for psychiatric diagnoses using the Kiddie-Sads-Present and Lifetime Version (K-SADS-PL). RESULTS: Using Analysis of covariance (ancova) we detected a significant group effect (patients with BD + ADHD had higher serum levels than those with ADHD - F80,3 = 8.73, P = 0.005). CONCLUSION: Although the Val66Met polymorphism at the BDNF gene does not seem to play a significant role in children and adolescents with BD or ADHD, BDNF serum levels deserve further attention in future research on neurobiological aspects of BD and ADHD.
Subject(s)
Attention Deficit Disorder with Hyperactivity/genetics , Bipolar Disorder/genetics , Brain-Derived Neurotrophic Factor/genetics , Polymorphism, Single Nucleotide , Adolescent , Brain-Derived Neurotrophic Factor/blood , Child , Child, Preschool , Female , Humans , Male , Psychiatric Status Rating ScalesABSTRACT
OBJECTIVE: The impact of childhood trauma (CT) on brain-derived neurotrophic factor (BDNF) and cytokines levels remains unclear. We investigated the association between CT and changes in BDNF and cytokines plasma levels in children. METHOD: We recruited 36 children with trauma (CT+) and 26 children without trauma (CT-). The presence of CT was based on a clinical interview and by Criteria A of DSM-IV criteria for PTSD. Blood samples were drawn from all children to assess BDNF and cytokines. ancova was performed with psychiatric symptoms and BMI as covariates to evaluate group differences in plasma levels. RESULTS: CT+ showed increased levels of BDNF and TNF-α after excluding children with history of inflammatory disease (P<0.05) when compared with those CT-. IL-12p70, IL-6, IL-8, IL-10, and IL-1ß levels were not statistically different between groups. CONCLUSION: CT+ showed increased BDNF and proinflammatory cytokines levels. The increase in BDNF levels may be an attempt to neutralize the negative effects of CT, while an increase in TNF-a levels be associated with a proinflammatory state after CT. How these changes associated with trauma relate to other biological changes and illness trajectory later in life remain to be further studied.
