Sex-specific neuroprotection: Does BDNF shield girls from autism?

Abstract

Autism Spectrum Disorder (ASD) exhibits a clear male bias, with males being approximately four times more likely to be affected than females. This difference has sparked curiosity about possible neurological elements that provide protection to females. One such neurological element that has shown promise is brain-derived neurotrophic factor (BDNF), essential for neuronal development, synaptic plasticity, and neuroprotection. ASD may be less common in females due to increased BDNF levels, which may be influenced by sex-specific epigenetic control and estrogen hormone. Research studies indicate that increased baseline BDNF in females promotes neurodevelopmental resilience and mitigates the environmental and genetic risk factors linked to ASD. Also, this protective impact may be enhanced by the regulatory function of estrogen in BDNF expression and the interaction of BDNF with X-linked genes. The processes by which BDNF contributes to sex differences are still not well understood despite strong evidence. Interpreting results is made more difficult by the variability of ASD symptoms and variations in study methodologies. In addition to that, it is yet unknown whether increased BDNF levels represent compensatory processes or actually provide protection. Longitudinal studies that monitor BDNF expression across developmental stages and look at sex-specific treatment approaches that target BDNF pathways should be the main focus of future research. Thus, a thorough understanding of how BDNF prevents sex differences in ASD may pave the way for innovative strategies destined to diminish the risk of ASD. In this milieu, this review explores the current research, highlighting the complex relationship between sex differences, BDNF, and the incidence of ASD.