Neuroprotective effects of Nigella sativa on experimental spinal cord injury in rats

The aim of this study was to investigate the possible beneficial effects of Nigella sativa (NS) in comparison to methylprednisolone on experimental spinal cord injury (SCI) in rats. SCI was performed by placing an aneurysm clip extradurally at the level of T11-12. Rats were neurologically tested over 24 h after trauma and spinal cord tissue samples were harvested for both biochemical and histopathological evaluation. The neurological scores of rats were not found to be different in SCI groups. SCI significantly increased the spinal cord tissue malondialdehyde (MDA) and protein carbonyl (PC) levels, however SCI decreased superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) enzyme activities compared to the control. Methylprednisolone and NS treatment decreased tissue MDA and PC levels and prevented inhibition of SOD, GSH-Px and CAT enzymes in the tissues. The most significant results were obtained when NS was given. In SCI and placebo groups, the neurons of spinal cord tissue became extensively dark and degenerated with picnotic nuclei. The morphology of neurons in methylprednisolone and NS-treated groups were well protected, however, not as well as the neurons of the control group. The number of neurons in the spinal cord tissue of the SCI and placebo groups was significantly less than the control, laminectomy, methylprednisolone and NS-treated groups. In conclusion, NS treatment might be beneficial in spinal cord tissue damage, and therefore shows potential for clinical implications.