Effect of Iridoid-rich Fraction from Valeriana Jatamansi Jones on Neuron Pyroptosis in Rats with Acute Spinal Cord Injury / 中国康复理论与实践

ABSTRACT

Objective:To investigate the effects of iridoid-rich fraction from Valeriana jatamansi Jones (IRFV) on neuronal pyroptosis in rats with acute spinal cord injury, and to explain the related mechanism of neuroprotection. Methods:Twenty-four healthy male Sprague-Dawley rats were randomly divided into sham-operated group, model group and treatment group, with eight rats in each group. The model of spinal cord injury was established by using a medical aneurysm clip in the latter two groups. Only the lamina was removed without injury to the spinal cord in the sham-operated group. Four hours after the operation, the treatment group was given IRFV solution 10 mg/kg, the model group and the sham-operated group were given the same volume of sodium carboxymethyl cellulose (CMC-Na) solution, for seven days. The rats were sacrificed to detected the pathological changes and the residual area of spinal cord tissue through HE staining. The apoptosis of nerve cells of the spinal cord tissue at the perilesional area was detected by TUNEL fluorescent staining. The levels of interleukin (IL)-1 and IL-18 in serum were detected by ELISA Kit and the expression of NLRP3, Caspase-1 and GSDMD were detected by Western blotting. Results:Compared with the sham-operated group, the residual area of spinal cord tissue decreased (P < 0.05), and the positive rate of TUNEL staining, the level of IL-1 and IL-18, and the expression of pyroptosis-associated proteins (NLRP3, Caspase-1 and GSDMD) increased (P < 0.05) in the model group. Compared with the model group, the pathological condition of the spinal cord tissue improved and the residual area of the spinal cord tissue increased (P < 0.05); the positive rate of TUNEL staining, the level of IL-1 and IL-18 and the expression of NLRP3, Caspase-1 and GSDMD decreased (P < 0.05) in the treatment group. Conclusion:IRFV could attenuate the inflammatory response to exert neuroprotective effects, which may be related to the regulation of NLRP3/Caspase-1 signaling pathway to inhibit the neuronal pyroptosis in rats with acute spinal cord injury.