Acute Transcriptomic and Epigenetic Alterations at T12 After Rat T10 Spinal Cord Contusive Injury.

Abstract

Spinal cord injury is a severely debilitating condition affecting a significant population in the USA. Spinal cord injury patients often have increased risk of developing persistent neuropathic pain and other neurodegenerative conditions beyond the primary lesion center later in their life. The molecular mechanism conferring to the "latent" damages at distal tissues, however, remains elusive. Here, we studied molecular changes conferring abnormal functionality at distal spinal cord (T12) beyond the lesion center (T10) by combining next-generation sequencing (RNA- and bisulfite sequencing), super-resolution microscopy, and immunofluorescence staining at 7days post injury. We observed significant transcriptomic changes primarily enriched in neuroinflammation and synaptogenesis associated pathways. Transcription factors (TFs) that regulate neurogenesis and neuron plasticity, including Egr1, Klf4, and Myc, are significantly upregulated. Along with global changes in chromatin arrangements and DNA methylation, including 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC), bisulfite sequencing further reveals the involvement of DNA methylation changes in regulating cytokine, growth factor, and ion channel expression. Collectively, our results pave the way towards understanding transcriptomic and epigenomic mechanism in conferring long-term disease risks at distal tissues away from the primary lesion center and shed light on potential molecular targets that govern the regulatory mechanism at distal spinal cord tissues.