title: Pilot Study and Review: Physiological Differences in BDNF, a Potential Biomarker in Males and Females with Autistic Disorder.
abstract: OBJECTIVE
  There is a need for more biologic research in autistic disorder (AD) to determine if biomarkers exist that would be useful for correlating to symptom severity and/or clinical improvement during treatment. Given the fact that AD is 4 times more common in males than females, gender differences in physiological biomarkers may be present. One potential biomarker that has begun to be studied is brain-derived neurotropic factor (BDNF), a peptide involved in the regulation of neuronal cell survival, differentiation, and plasticity, and possessing an ability to influence neurotransmitter systems by modulating gene expression. This pilot study examined whether serum BDNF differed according to gender in children with AD and whether differences were associated with a behavioral phenotype or severity of illness.
  
  
  METHODS
  Data for this investigation were collected during the participants' baseline visit of an intervention study. Participants were males (n=29) and females (n=7), aged 5 to 12 years diagnosed with AD. Baseline serum BDNF concentration was determined for comparison to clinical ratings using an autism severity measure and the Pervasive Developmental Disorder-Behavior Inventory (PDD-BI).
  
  
  RESULTS
  BDNF serum concentrations were higher in females (p<0.049). The baseline BDNF value corresponded significantly to hyperactivity in females (p<0.0002) but not in males. BDNF did not correlate with severity of disease in either gender.
  
  
  CONCLUSIONS
  Although this is a small study, a better understanding of the central role of BDNF may provide insight into the pathophysiology of the disease and elucidate why gender differences exist in prevalence and behavioral phenotype of AD.
authors: Department of Pediatrics, Division of Developmental and Behavioral Pediatrics, Medical University of South Carolina, Charleston, SC, United States; Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States.
authors: Eve G
authors: EG
authors: Spratt
authors: Department of Neuroscience and the Center on Aging, Medical University of South Carolina, Charleston, SC, United States.
authors: Ann-Charlotte
authors: AC
authors: Granholm
authors: Department of Pediatrics, Division of Developmental and Behavioral Pediatrics, Medical University of South Carolina, Charleston, SC, United States.
authors: Laura A
authors: LA
authors: Carpenter
authors: Department of Neuroscience and the Center on Aging, Medical University of South Carolina, Charleston, SC, United States.
authors: Heather A
authors: HA
authors: Boger
authors: Department of Pediatrics, Division of Developmental and Behavioral Pediatrics, Medical University of South Carolina, Charleston, SC, United States.
authors: Carrie E
authors: CE
authors: Papa
authors: Department of Healthcare Leadership and Management, Medical University of South Carolina, Charleston, SC, United States.
authors: Sarah
authors: S
authors: Logan
authors: Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States.
authors: Humera
authors: H
authors: Chaudhary
authors: School of Medicine, Medical University of South Carolina, Charleston, SC, United States.
authors: Sarah-Wade
authors: SW
authors: Boatwright
authors: Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States; Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC, United States.
authors: Kathleen T
authors: KT
authors: Brady
keywords: BDNF; autism; brain-derived neurotropic factor; gender; hyperactivity