RESUMO
Objective:To study the effects of tetramethylpyrazine on the expressions of ferroptosis related molecules after spinal cord injury; To explore the mechanism of tetramethylpyrazine promoting the repair of spinal cord injury (SCI).Methods:Totally 36 SD rats were divided into sham-operation group, model group and tetramethylpyrazine group according to random number table method, with 12 rats in each group. The rats in the sham-operation group underwent laminectomy without injury to the spinal cord. The SCI model was prepared in the other two groups. The rats in the tetramethylpyrazine group were intraperitoneally injected with tetramethylpyrazine of 80 mg/kg, and the rats in the sham-operation group and model group were intraperitoneally injected with the same volume of normal saline, once a day, continuous intervention for 28 days. One day before operation and 1, 3, 5, 7, 14, 21, 28 days after operation, BBB limb motor function score was used to evaluate the limb motor function of rats. Nissl staining was used to observe the morphology of neurons. Prussian staining was used to observe iron deposition. Assay kit was used to detect the contents of MDA and ROS in spinal cord tissue. Western blot was used to detect the protein expressions of xCT, GPX4 and ACSL4, and qPCR was used to detect the mRNA expressions of mRNA of xCT, GPX4 and ACSL4.Results:On the 14th, 21st and 28th days after operation, compared with the model group, the BBB score of tetramethylpyrazine group increased ( P<0.01); tetramethylpyrazine could significantly improve the morphology and structure of neurons and reduce the iron content in spinal cord tissue; compared with the model group, the contents of MDA and ROS in the spinal cord tissue of tetramethylpyrazine group decreased ( P<0.01); the levels of xCT and GPX4 mRNA and protein increased ( P<0.01), while the expression of ACSL4 mRNA and protein decreased ( P<0.01). Conclusion:Tetramethylpyrazine can regulate lipid peroxidation by regulating the expressions of ferroptosis related molecules, which is conducive to the recovery of limb motor function in rats with spinal cord injury.