Biology subjects

Gao, X.-B.

Publications and source records attributed to Gao, X.-B..

2 recordsLinked to original sources

bioRxiv2020

Ucp2-dependent microglia-neuronal coupling controls ventral hippocampal circuit function and anxiety-like behavior

Microglia have been implicated in synapse remodeling by phagocytosis of synaptic elements in the adult brain. However, the underlying mechanism of such process is ill-defined. By examining microglia-neuronal interaction in the ventral hippocampus, we found a significant reduction in spine synapse number during the light phase of the light/dark cycle accompanied by increased microglial phagocytosis. This was followed by a transient rise in microglial production of reactive oxygen species (ROS) and uncoupling protein 2 (Ucp2) expression, which is a regulator of mitochondrial ROS generation. Conditional ablation of microglial Ucp2 hindered phasic elimination of spine synapses, increased accumulations of ROS and lysosome-lipid droplet complexes leading to hippocampal circuitry disruption assessed by electrophysiology, and, altered anxiety-like behavior. These observations unmasked a novel and chronotypical interaction between microglia and neurons involved in control of brain functions.

neuroscience↗

bioRxiv2020

Acetylcholine is released in the basolateral amygdala in response to predictors of reward and enhances learning of cue-reward contingency

The basolateral amygdala (BLA) is critical for associating initially neutral cues with appetitive and aversive stimuli and receives dense neuromodulatory acetylcholine (ACh) projections. We measured BLA ACh signaling and principal neuron activity in mice during cue-reward learning using a fluorescent ACh sensor and calcium indicators. We found that ACh levels and activity of nucleus basalis of Meynert (NBM) cholinergic terminals in the BLA (NBM-BLA) increased sharply in response to reward-related events and shifted as mice learned the tone-reward contingency. BLA principal neuron activity followed reward retrieval and moved to the reward-predictive tone after task acquisition. Optical stimulation of cholinergic NBM-BLA terminal fibers during cue-reward learning led to more rapid learning of the cue-reward contingency. These results indicate that BLA ACh signaling carries important information about salient events in cue-reward learning and provides a framework for understanding how ACh signaling contributes to shaping BLA responses to emotional stimuli.

neuroscience↗