GSE176140
Early life inflammation promotes depressive symptoms in adolescents via microglial engulfment of dendritic spines
Early life inflammation is known to promote the risk of depression in later life. Here, we demonstrate how early life inflammation causes adolescent depressive-like symptoms: by altering the long-term neuronal spine engulfment capacity of microglia. For mice exposed to lipopolysaccharide (LPS)-induced inflammation via the Toll-like receptor 4/NF-?B signaling pathway at postnatal day 14 (P14), ongoing longitudinal imaging of the living brain revealed that later stress (delivered during adolescence on P45) increases the extent of microglial engulfment around anterior cingulate cortex (ACC) glutamatergic neuronal (ACCGlu) spines. Through bluk RNA-seq of ACC tissue, we find that the fractalkine receptor CX3CR1 mediates stress-induced engulfment of ACCGlu neuronal spines. Overall design: mRNA profiles of ACC in P45 mice that were treated with saline or LPS on P14