[Gene expression profile in acute spinal cord injury screened by cDNA microarray: experiment with rats]

Abstract

Objective: To investigate the characteristic changes of expression of the genes with specific functions in acute spinal cord injury (SCI).

Methods: Nine SD rats were randomly divided into 3 equal groups: SCI 8-hour group in which modified Allen's falling strike method was used to establish spinal cord contusion model, the spinal cords were taken out 8 hours later to undergo examination of the gene expression profile by using cDNA microarray including 13 200 gene, 12 genes were selected to undergo semi-quantitative RT-PCR, and the up-regulation of the candidate gene C/EBPdelta was verified by in situ hybridization and immunohistochemistry.; SCI 72-hour group undergoing the same treatment, however, with the spinal cord taken out 72 hours later; and control group undergoing only sham operation with the spinal cord taken out immediately.

Results: In the SCI 8 hour group the expression of 52 genes differed in comparison with the control group, 30 genes, including those related to transcription factors, oxidative stress, complement, pro-inflammatory reaction, and anti-inflammatory reaction, were up-regulated and 22 genes related to ion channel, synaptic proteins, and cytoskeletal proteins, were down-regulated. In the SCI 72-hour group the expression of 44 genes with known functions related to growth/differentiation/survival, axonal guidance, neuron regeneration, signal transduction, ubiquitin-proteasome system, and tumor suppressor differed, 26 genes were up-regulated and 18 down-regulated, in comparison with the control group. Semi-quantitative RT-PCR results of the 12 genes were consistent with those by the microarray examination.

Conclusion: Significant changes occur in the early stage of SCI. Expressed at a high level in SCI, C/EBPdelta may be a therapeutic target of SCI.