Dysregulated MiR-223-5p Modulates Inflammation and Oxidative Stress in Traumatic Spinal Cord Injury.

Aim: This study aimed to evaluate the miR-223-5p expression in patients with spinal cord injury (SCI) and to determine its role in the pathogenesis of SCI.

Methods: The serum miR-223-5p levels were analyzed using quantitative real-time polymerase chain reaction. The diagnostic accuracy of miR-223-5p was evaluated using the receiving operating characteristic curves. LPS-induced PC12 cells were established as an in vitro inflammatory cell model. Cell apoptosis, inflammation and oxidative stress were examined. The SCI rat model was constructed to evaluate the effects of miR-223-5p on inflammatory response and motor function in rats.

Results: MiR-223-5p expression was upregulated in SCI patients. MiR-223-5p expression in the complete SCI group was significantly higher than that in incomplete SCI group. ROC analysis showed that miR-223-5p can distinguish SCI patients from healthy volunteers. In vitro experiments demonstrated that LPS upregulated apoptosis and inflammation in PC12 cells. Treatment with miR-223-5p inhibitor alleviated the changes in LPS-induced PC12 cells . Inhibition of miR-223-5p can alleviate the activation of inflammatory response and the effects of SCI on the motor function in rats.

Conclusions: MiR-223-5p is a potential diagnostic marker for SCI, and it can promote the SCI progression by regulating nerve cell survival, inflammation, and oxidative stress.