Early Isoflurane Exposure Is Associated With Delayed Adolescent Neurobehavioral Deficits, Accompanied by Dysregulation of FOXG1 and EB3.

Early-life exposure to general anesthetics has been linked to long-term neurodevelopmental risks, yet the underlying mechanisms remain unclear. Using a mouse model, we show that neonatal isoflurane exposure at Postnatal Day 7 leads to age-dependent behavioral alterations, changes in cortical neuronal abundance and layer-specific neuronal density, and dysregulation of cytoskeleton-associated proteins. Isoflurane-exposed mice displayed increased exploratory behavior during early adolescence but developed marked recognition memory deficits by late adolescence. Histological analyses revealed layer-specific disruption of neuronal distribution in the sensory cortex, characterized by reduced neuronal density in layers II-IV and age-dependent changes in inhibitory interneuron composition. Mechanistically, isoflurane reduced the expression of the microtubule plus-end tracking protein EB3 and the transcription factor FOXG1. FOXG1 co-localized with EB3 and β-tubulin in the cytoplasm, supporting a noncanonical, cytoskeleton-associated role. Together, these findings indicated that early isoflurane exposure is associated with altered neuronal density and dysregulation of the cytoskeleton-associated proteins FOXG1 and EB3, suggesting a potential link between anesthesia exposure and long-term neurodevelopmental alterations.