Transcriptional and Epigenetic Regulation in Injury-Mediated Neuronal Dendritic Plasticity

Injury to the nervous system induces localized damage in neural structures and neuronal death through the primary insult,as well as delayed atrophy and impaired plasticity of the delicate dendritic fields necessary for interneuronal communication. Excitotoxicity and other secondary biochemical events contribute to morphological changes in neurons following injury. Evidence suggests that various transcription factors are involved in the dendritic response to injury and potential therapies. Transcription factors play critical roles in the intracellular regulation of neuronal morphological plasticity and dendritic growth and patterning. Mounting evidence supports a crucial role for epigenetic modifications via histone deacetylases,histone acetyltransferases,and DNA methyltransferases that modify gene expression in neuronal injury and repair processes.Gene regulation through epigenetic modification is of great interest in neurotrauma research,and an early picture is beginning to emerge concerning how injury triggers intracellular events that modulate such responses. This review provides an overview of injury-mediated influences on transcriptional regulation through epigenetic modification,the intracellular processes involved in the morphological consequences of such changes,and potential approaches to the therapeutic manipulation of neuronal epigenetics for regulating gene expression to facilitate growth and signaling through dendritic arborization following injury.