加减旋覆花汤对坐骨神经损伤大鼠疼痛行为及p38MAPK信号通路介导的脊髓神经炎症的影响

Effects of modified Xuanfuhua Decoction on pain behavior and p38MAPK signaling pathway-mediated spinal cord neuroinflammation in rats with sciatic nerve injury

目的观察加减旋覆花汤对坐骨神经损伤大鼠疼痛行为及磷酸化p38有丝分裂原激活蛋白激酶(p38MAPK)信号通路介导的脊髓神经炎症的影响,并探讨其作用机制。方法将108只SD大鼠按随机数字表法分为假手术组、模型组、普瑞巴林组及汤药低、中、高剂量组,每组18只。除假手术组外,其余各组采用结扎坐骨神经法建立坐骨损伤(CCI)模型。汤药低、中、高剂量组分别灌胃2.5、5.0、10.0 g/kg的加减旋覆花汤浓缩液,普瑞巴林组灌胃15 mg/kg的普瑞巴林,假手术组与模型组灌胃等体积生理盐水,1次/d,连续15 d。分别于给药前及给药第3、7、11、15 d进行疼痛行为学检测;采用ELISA法检测脊髓中IL-1β、TNF-α、IL-10水平,采用免疫组化染色检测TLR4、NF-κB p65表达,采用Western blot法检测磷酸化p38MAPK(p-p38MAPK)表达。结果与模型组比较,汤药高剂量组自发性疼痛评分降低(P<0.05),热辐射缩足潜伏期(TWL)延长(P<0.05),机械缩足反射阈(MWT)升高;汤药低、中、高剂量组脊髓组织IL-1β、TNF-α水平降低(P<0.05),IL-10水平升高(P<0.05);脊髓组织TLR4、NF-κB p65平均灰度值降低(P<0.05),p-p38MAPK蛋白表达降低(P<0.05)。结论加减旋覆花汤可有效改善CCI大鼠神经源性疼痛,其机制可能与抑制p38MAPK-TLR4信号通路激活介导的脊髓神经炎症有关。

Objective To observe the effects of modified Xuanfuhua Decoction on pain behaviour and spinal cord neuroinflammation mediated by phosphorylated mitogen-activated protein kinase p38(p38MAPK)signaling pathway in rats with sciatic nerve injury;To analyse the mechanism of its effects.Methods Totally 108 SD rats were randomly divided into sham-operation group,model group,pregabalin group,decoction low-,medium-and high-dosage groups,with 18 rats in each group.The CCI model was established by ligation of sciatic nerve in other groups except sham-operation group.On the postoperative day,the decoction low-,medium-,high-dosage groups were gavaged with 2.5,5.0 and 10.0 g/kg of modified Xuanfuhua Decoction concentrate,respectively.The pregabalin group was gavaged with 15 mg/kg of pregabalin.The sham-operation group and the model group were gavaged with equal amounts of saline once/d for 15 days.Pain behavioural assays were performed before,on the 3rd,7th,11th and 15th day of administration respectively.The levels of interleukin(IL)-1β,tumour necrosis factor-α(TNF-α),IL-10 were detected by ELISA method.The expressions of Toll-like receptor 4(TLR4),nuclear factor-κB p65(NF-κB p65)were detected by immunohistochemistry staining.The phosphorylated p38MAPK(p-p38MAPK)were measured in the spinal cord by Western blot.Results Compared with the model group,the scores of spontaneous pain in decoction high-dosage group decreased(P<0.05),the thermal foot shrinkage latency(TWL)was prolonged(P<0.05),and the mechanical foot shrinkage reflex threshold(MWT)increased(P<0.05);the levels of IL-1βand TNF-αin spinal cord tissue of decoction low-,medium-and high-dosage groups decreased(P<0.05),the level of IL-10 increased(P<0.05),the average gray values of TLR4 and NF-κB p65 in spinal cord decreased(P<0.05),and the expression of P-P38MAPK protein decreased(P<0.05).Conclusion Modified Xuanfuhua Decoction can effectively improve neurogenic pain in CCI rats,and the mechanism may be related to inhibition of p38MAPK-TLR4 signaling pathway activation-mediated spinal cord neuroinflammation.