Negative feedback control of neuronal activity by microglia

The neuronal network output depends on the tight coordination between excitatory and inhibitory neuron activity. We found that microglia have the ability to sense and respond to changes in neuronal activity in a rapid and activity-dependent fashion and operate as a potent suppressor of neuronal network activity. The microglia-mediated neuronal suppression depends on a simple negative feedback mechanism that involves the recruitment of microglia protrusion to active neuronal synapses followed by the suppression of neuronal activation by microglia produced metabolites. We will discuss the mechanisms of the process and the nature of microglia metabolites that suppress neuron activity.