ABSTRACT
Neuregulin-1 (NRG1) is a growth factor that belongs to a family of polypeptide growth factors encoded by four neuregulin genes. NRG1 signals are transduced through the ErbB family of receptor protein tyrosine kinases, in which NRG1 binding results in phosphorylation and dimerization of these receptors, leading to activation of downstream pathways. NRG1/erbB signaling is involved in cellular processes including cell survival, proliferation, migration, and differentiation. In the CNS, NRG1/ErbB4 signaling also affects dendritic spine maturation and the formation of inhibitory synapses. Neuregulin-1/ErbB signaling has been shown to have beneficial effects on many of the different types of cells in the brain, including neurons, astrocytes, oligodendrocytes, oligodendrocyte precursor cells, endothelial cells, and microglia. Many of these actions may have neuroprotective potential in the setting of traumatic brain injury, and will be further discussed in this chapter.
