Effect of methylprednisolone pre-intervention on expressions of heat shock protein 27 and tumor necrosis factor alpha in spinal cord cells following ischemia-reperfusion injury in rats

Objective To observe the effect of methylprednisolone (MP) pre-intervention on ex-pressions of heat shock protein 27 (HSP27) and tumor necrosis factor alpha (TNF-α) in cells in rat spinal cord following ischemia-reperfusion injury. Methods One hundred and fifty male Sprague-Dawley (SD) rats were randomly divided into 3 equal groups: group A (control) in which the abdominal aorta was exposed without any treatment, group B in which the abdominal aorta was clipped for 30 minutes before reperfusion for 3 bours to establish a model of ischemia- reperfusion injury, and group C in which intravenous MP injection was conducted 30 minutes before the establishment of the ischemia-reperfusion injury model. Three hours later the spinal cords were harvested. Pathological changes of spinal cord cells were observed with HE staining and expressions of HSP27 and TNF-α in spinal cord cells were observed with immunohistochemical staining. The motor function of hind-limbs before was evaluated before sample harvest. The data were analyzed with SPSS software. Results There were significant differences between groups A and B in the expressions of TNF-α and HSP27. Compared with group B, the expression of TNF-α decreased and HSP27 increased in group C, with statistically significant differences between the 2 groups. The motor function score of hind-limbs decreased in group B but improved in group C. Conclusions Since MP can decrease the expression of TNF-α and up-regulate the expression of HSP27, it has a potency of neuro-protection. Spinal cord ischemia-reperfusion injury can be avoided or decreased after MP pre-intervention. Key words: Methylprednisolone; Spinal cord ischemia; Reperfusion injury; Heat-shock pro-teins; Tumor necrosis factor-α