Synaptic NMDA receptor activity is coupled to the transcriptional control of the glutathione system

How the brain's antioxidant defenses adapt to changing demand is incompletely understood. Here we show that synaptic activity is coupled, via the NMDA receptor (NMDAR), to control of the glutathione antioxidant system. This tunes antioxidant capacity to reflect the elevated needs of an active neuron, guards against future increased demand and maintains redox balance in the brain. This control is mediated via a programme of gene expression changes that boosts the synthesis, recycling and utilization of glutathione, facilitating ROS detoxification and preventing Puma-dependent neuronal apoptosis. Of particular importance to the developing brain is the direct NMDAR-dependent transcriptional control of glutathione biosynthesis, disruption of which can lead to degeneration. Notably, these activity-dependent cell-autonomous mechanisms were found to cooperate with non-cell-autonomous Nrf2-driven support from astrocytes to maintain neuronal GSH levels in the face of oxidative insults. Thus, developmental NMDAR hypofunction and glutathione system deficits, separately implicated in several neurodevelopmental disorders, are mechanistically linked.