Dysfunction of microglia-mediated synaptic pruning in Autism spectrum disorder

Autism spectrum disorder (ASD) has been increasingly associated with abnormalities in synaptic pruning. Although significant progress has been made in elucidating the genetic and immunological underpinnings of ASD, its core pathological mechanisms remain poorly understood. In this study, we developed a network model integrating the inflammatory response pathway in microglia with synaptic signaling pathway to investigate how lipopolysaccharide (LPS) and synaptic activity jointly regulate microglia--mediated synaptic pruning. Our results reveal that pro-inflammatory activation of microglia impairs pruning efficiency under reduced synaptic activity, leading to excessive synaptic accumulation particularly in the prefrontal cortex and contributing to ASD-like phenotypes. Conversely, enhanced synaptic activity partially suppresses LPS-induced synaptic apoptosis and promotes synaptic retention. These findings suggest multiple therapeutic strategies, including targeting pruning-related molecular pathways, mitigating neuroinflammation, and modulating synaptic excitability to alleviate ASD symptoms.