Clinical significance of miR-142-5p in spinal cord injury caused by spinal trauma and its functional role in the regulation of inflammation.

Objective: Spinal cord injury (SCI) is a severe traumatic disease in the central nervous system, and can result in neuronal injury. Altered miRNA expression is identified to be involved in the pathogenesis of SCI.

Design: This study investigated the clinical value of miR-142-5p in SCI patients, and explored its functional role in the regulation of inflammatory.

Setting: The First Affiliated Hospital of Soochow University.

Participants: Ninety-eight patients with acute spinal trauma.

Interventions: All patients were recruited, and divided into complete SCI group, incomplete SCI group and normal nerve function group.

Outcome measures: Real-time quantitative PCR (qRT-PCR) was used to detect the expression levels of miR-142-5p. CCK-8 and flow cytometry assay were performed to evaluate the cell viability and apoptosis. ELISA assay was applied to estimate the levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α).

Results: Serum miR-142-5p level was significantly increased in SCI patients, especially the complete SCI cases. ROC curve analysis suggested miR-142-5p could distinguish SCI patients from normal nerve function patients and was associated with the severity of SCI. A positive association was detected between miR-142-5p and serum levels of IL-6, TNF-α in SCI patients. Downregulation of miR-142-5p significantly reduced the protein levels of both IL-6 and TNF-α in LPS treated PC12 cells, and weakened LPS induced cell apoptosis.

Conclusion: MiR-142-5p is a potential biomarker for the occurrence of SCI in acute spinal trauma patients. Downregulation of miR-142-5p plays an anti-inflammatory effect for SCI patients.