Zinc homeostasis and signaling in glia

The role of zinc in neurobiology has been the subject of intense interest particularly because of zinc's presence in and release from glutamatergic synapses, and its association with major neurological disorders. Initially considered inert to Zn ²⁺ signaling and resistant to Zn ²⁺ toxicity, glia, like neurons, is now known to be vulnerable to Zn ²⁺, albeit to a lesser degree and in ways that are type-specific. The discovery of Zn ²⁺ transporters and the development of highly sensitive zinc sensors has led to a new understanding regarding the role of this metal ion in glial physiology. Dynamic changes in Zn ²⁺ content are now linked to executive functions, signaling and fate in glia. In this review, we focus on these issues and discuss the broader implication of glial Zn ²⁺ signaling in neuron glial-interactions.