Ferulic acid improves motor function induced by spinal cord injury in rats via inhibiting neuroinflammation and apoptosis

PURPOSE: To investigate the effect of ferulic acid (FA) on spinal cord injury (SCI)-induced motor dysfunction and to explore the possible pharmacological mechanisms. METHODS: Adult male Wistar rats were used in our study. SCI was achieved by clipping the spinal cord T9 of the rat by a vascular clip for 2 minutes. The motor function of the rat was evaluated by Basso, Beattie, and Bresnahan scoring method (BBB) and inclined plane test. Hematoxylin and eosin (HE) staining, NISSL staining, and transmission electron microscopic examination were used to evaluate alterations at the histological level. Polymerase chain reaction (PCR), Western blots, and enzyme-linked immunosorbent assays (ELISA) were employed in biochemical analysis. RESULTS: The BBB score and inclined plane test score significantly decreased after SCI surgery, whereas chronic FA treatment (dose of 90 mg/kg, i.g.) for 28 days improved SCI-induced motor dysfunction. HE staining showed that SCI surgery induced internal spinal cord edema, but the structural changes of the spinal cord could be reversed by FA treatment. NISSL staining and transmission electron microscopic examination confirmed the improvement of the effect of FA on the injury site. In the biochemical analysis, it could be found that FA inhibitedSCI-induced mRNA and protein overexpression of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α), as well as iNOS and COX-2 via the modulation of NF-κB level in the spinal cord of SCI rat. Moreover, the SCI-induced decrease of Bcl-2/Bax ratio was also reversed by FA treatment. However, the effect of FA on the expression of Beclin-1 was not statistically significant. CONCLUSIONS: FA showed a therapeutic effect on SCI, which may be associated with the regulation of neuroinflammation and apoptosis.