Increased serum levels of brain-derived neurotrophic factor in autism spectrum disorder

Abstract

The aim of this study was to investigate the potential role of brain-derived neurotrophic factor (BDNF) in children with autism spectrum disorders (ASD) by measuring serum circulating levels of BDNF as well as calcium and comparing them with age-matched and sex-matched normal controls. The study included 75 drug-naive ASD children and 75 age-sex-matched healthy children. The concentration of serum BDNF was determined using the enzyme-linked immunosorbent assay method at baseline. Clinical information was collected. The severity of ASD was assessed at admission using the Childhood Autism Rating Scale total score. The results indicated that the mean serum BDNF levels were significantly (P<0.0001) higher in children with ASD compared with the control cases (17.59±5.55 vs. 11.21±2.79 ng/ml; t=8.902). On the basis of the receiver operating characteristic curve, the optimal cutoff value of serum BDNF levels as an indicator for auxiliary diagnosis of autism was projected to be 12.65 ng/ml, which yielded a sensitivity of 80.8% and a specificity of 70.2%; the area under the curve was 0.840 [95% confidence interval (CI), 0.777-0.904]. In univariate logistic regression analysis, with an unadjusted odds ratio of 9.42 (95% CI, 4.33-25.95; P<0.0001), BDNF of 12.65 ng/ml or more had an association with a diagnosis of ASD. After adjusting for possible covariates, BDNF of 12.65 ng/ml or more is still an independent indicator of ASD, with an adjusted odds ratio of 7.33 (95% CI, 2.98-16.55; P<0.0001). Serum BDNF levels may be associated independently with the severity of ASD, and higher BDNF levels could be considered an independent diagnostic marker of ASD.

The BTBR mouse model of idiopathic autism – Current view on mechanisms

“…No significant difference was obtained for NGF (nerve growth factor) between the two strains (Hwang et al 2015). The upregulation of BDNF expression at an early developmental stage (in stark contrast to the BDNF signaling deficiency in later life of BTBR mice) is in line with clinical data showing increased plasma BDNF in children with ASD (Wang M. et al 2015). …”

Autistic traits and neuropsychological performance in 6- to-10-year-old children: a population-based study

“…BDNF is involved in activity-dependent synaptic plasticity and there have been a number of studies linking BDNF with ASD (Armeanu, Mokkonen, & Crespi, 2017;Bryn et al, 2015;Kasarpalkar, Kothari, & Dave, 2014;Saghazadeh & Rezaei, 2017;Wang et al, 2015). Within the context of a genetic predisposition for ASD, coupled with environmental factors that result in over excitation of neurons, BDNF levels increase dramatically, resulting in the presence of a fatty coating around the neurons and megalencephaly (Merzenich, Van Vleet, Nahum, 2014).…”

Brain‐derived neurotrophic factor (BDNF) in children with ASD and their parents: a 3‐year follow‐up

“…The age of the subjects is a possible factor given the change of the BDNF levels over lifetime and the different developmental trajectories between the ASD subjects and the neurotypical counterparts . Our sample group was 30–42 months of age, that is slightly younger than that of Enstrom et al , Zhang et al , Wang et al and Meng et al that all found increased levels in children with ASD. However, as shown by our follow‐up results, BDNF levels seem to change significantly in ASD populations, even in short time in this critical young age.…”

“…Finally, after Nelson et al first report of higher BDNF levels in neonatal blood of children with ASD, multiple studies examined its serum levels with even the ambition to use them as a diagnostic or prognostic marker. Unfortunately, these studies have been yielding inconsistent results (Table ) . However, four recent published meta‐analyses (roughly using the same studies) all reported higher levels of BDNF in children with ASD, but also significant statistical heterogeneity across studies .…”