Mechanism of action and therapeutic targeting of microglia in autism spectrum disorder

Autism spectrum disorder (ASD) is a complex mental illness with a high incidence and considerable impact. More than half of the affected individuals have self-harm behaviors, resulting in high mortality and morbidity. The impact of ASD on education and employment opportunities, the need for family care and support, as well as the burden on families and society is enormous. The underlying pathogenesis of ASD is still unclear, and effective interventions are lacking. Microglia are key immune cells in the central nervous system (CNS), and they function far beyond classical innate immunity, as they can affect normal neuronal activity by secreting cytokines and pruning synapses through phagocytosis. On the one hand, the abnormal activity of microglia may contribute to the development of ASD; on the other hand, it provides a potential target for intervention and treatment. In this review, we comprehensively analyze the mechanism of action of microglia in ASD development and summarize the current methods for targeting microglia in treating ASD.
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