Effects of individual or combined use of alpha-lipoic acid and methylprednisolone on malondialdehyde, superoxide dismutase, and catalase levels in acute spinal cord injury in rats

Abstract

Introduction: Recent studies have demonstrated that alpha-lipoic acid (ALA) has a strong antioxidant property and it exerts neurotrophic effects on the peripheral nerves. In this study, we investigated potential effects of ALA on secondary injury mechanisms as well as on apoptosis.
Methods: Forty Sprague-Dawley rats were equally divided into 5 groups, as follows: laminectomy (control), laminectomy + trauma (Trauma), laminectomy + posttraumatic methylprednisolone [MP] (Trauma + MP), laminectomy + posttraumatic ALA (Trauma + ALA), laminectomy + posttraumatic MP and ALA (Trauma + MP + ALA). Yasargil aneurysm clip method was used to induce the spinal cord injury. Twenty-four hours after the procedure the rats were sacrificed. Spinal cord samples were harvested to analyze malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels, as well as histopathological characteristics.
Results: The Kruskal-Wallis test (95% confidence level, p < 0.05) showed a statistically significant difference between the groups in MDA (p = 0.006), CAT (p = 0.000), and SOD (p = 0.001) levels. Pairwise comparisons, with Bonferroni correction, of control and Trauma group with the other groups, revealed a significant difference in CAT and SOD levels. Overall, our results showed that ALA administration significantly decreased MDA levels in Trauma + ALA compared to the same effect of MP in Trauma + MP group. Furthermore, ALA administration increased SOD and CAT levels in Trauma + ALA group. The combined use of ALA and MP demonstrated synergistic effects and yielded even more significant results.
Conclusions: A combined use of ALA and MP might provide a benefit in patients exposed to spinal cord injury. However, at present, further studies are required to confirm these results.