Granulocyte Colony‐Stimulating Factor Has a Sex‐Dependent Positive Effect in the Maternal Immune Activation‐Induced Autism Model

Objective The medical intervention for autism spectrum disorder (ASD) is restricted to ameliorating comorbid situations. Granulocyte colony-stimulating factor (G-CSF) is a growth factor that enhances the proliferation, differentiation, and survival of hematopoietic progenitor cells. In the present study, we aimed to investigate the effects of G-CSF in a maternal immune activation-induced autism model. Methods Sixteen female and six male Wistar adult rats were included in the study. After 21 days, 48 littermates (eight male controls, eight female controls, 16 male lipopolysaccharide [LPS]-exposed rats, and 16 female LPS-exposed rats) were divided into groups. Sixteen male LPS-exposed and 16 female LPS-exposed rats were divided into saline and G-CSF treatment groups. Results In male rats, the LPS-exposed group was found to have significantly higher levels of TNF-alpha, IL-2, and IL-17 than the LPS-exposed G-CSF group. Levels of nerve growth factor, brain PSD-95, and brain GAD67 were higher in the LPS-exposed G-CSF group than in the LPS-exposed group in male rats. In female rats, brain NGF levels were similar between groups. There was no difference between groups in terms of brain GAD 67 levels. Brain PSD-95 levels were higher in the control group than in both the LPS-exposed and LPS-exposed G-CSF groups in female rats. Both neuronal CA1 and neuronal CA2 levels were lower, and the GFAP immunostaining index (CA1) and GFAP immunostaining index (CA3) were higher in the LPS-exposed group than in the LPS-exposed G-CSF group in male rats. However, neuronal count CA1 and neuronal count CA3 values were found to be similar between groups in female rats. Conclusions The present research is the first to demonstrate the beneficial effects of G-CSF on core symptoms of ASD experimentally depending on male sex. G-CSF can be a good candidate for ameliorating the core symptoms of ASD without serious side effects in males.