祛风骨痛巴布膏对肌筋膜疼痛综合征模型大鼠的干预作用及机制研究

Intervention effect of Qufeng Gutong Cataplasm on myofascial pain syndrome in rats and its mechanism

旨在研究祛风骨痛巴布膏对肌筋膜疼痛综合征(myofascial pain syndrome,MPS)大鼠的干预作用,并从改善肌肉炎症疼痛角度初步探索作用机制。将SD雄性大鼠分成6组,为正常组、模型组、阳性药活血止痛膏组以及祛风骨痛巴布膏低、中、高剂量组(75、150、300 mg·d-1)。通过打击结合离心运动法建立MPS动物模型,造模期间,外用贴敷祛风骨痛巴布膏进行干预,同时以活血止痛膏进行同种方式给药对照。标准VonFrey纤维评价机械痛阈值;丙酮检测冷痛阈值;检测触发点肌肉电生理活动,并进行触发点肌肉电分析;CatWalk步态分析仪检测疼痛诱导的步态适应性变化;苏木素-伊红(HE)染色观察大鼠触发点肌肉和给药处皮肤组织病理变化;免疫组化法检测触发点肌肉组织中辣椒素受体1(TRPV1)以及皮肤组织中白细胞介素(IL)-33的表达;蛋白质免疫印迹检测触发点肌肉组织中TRPV1、磷脂酰肌醇3-激酶(PI3K)、蛋白激酶B(Akt)、磷酸化蛋白激酶B(p-Akt)、IL-1β和肿瘤坏死因子-α(TNF-α)的蛋白表达水平。结果发现,与模型组相比,祛风骨痛巴布膏外贴后,各组大鼠机械痛敏阈值和冷痛阈值升高;模型组出现自发肌电活动,而祛风骨痛巴布膏能剂量依赖地减弱自发肌电活动;步态分析显示祛风骨痛巴布膏各组对站立持续时间、平均强度、摆动速度、最大接触点、最大接触面积、爪印长度、爪印宽度、爪印面积都有明显提升;病理分析显示祛风骨痛巴布膏治疗后触发点处肌肉排列紊乱程度下降,肌纤维黏连及萎缩减少,炎性细胞浸润现象有所缓解;此外,祛风骨痛巴布膏和活血止痛膏均在一定程度上抑制MPS大鼠触发点肌肉组织中TRPV1、PI3K、Akt、p-Akt、IL-1β和TNF-α等相关蛋白表达,而给药皮肤位置病理结构及IL-33表达较正常组相比无显著差异。相关研究结果证实祛风骨痛巴布膏能通过抑制MPS模型大鼠肌肉触发点中TRPV1/PI3K/Akt信号通路进而抑制炎性因子释放,最终减弱局部肌肉的萎缩黏连及炎性浸润,缓解MPS大鼠肌肉疼痛,且局部给药无皮肤刺激作用。

This paper aims to investigate the intervention effect of Qufeng Gutong Cataplasm(QFGT)on myofascial pain syndrome(MPS)in rats and to preliminarily explain its mechanism from the perspective of improving muscle inflammation and pain.Male SD rats were divided into 6 groups,namely normal group,model group,positive control drug(Huoxue Zhitong Ointment,HXZT)group,and low,medium,and high-dose QFGT groups(75,150,and 300 mg·d-1).The rat model of MPS was established by striking combined with centrifugation for 8 weeks,during which QFGT and HXZT were used for corresponding intervention.Standard VonFrey fiber was used to evaluate the mechanical pain threshold,and acetone was used to detect the cold pain threshold.The electrophysiological activity of muscle at trigger point was detected,and the electromuscular analysis of trigger point was performed.CatWalk gait analyzer was used to detect pain-induced gait adaptation changes.The hematoxylin-eosin(HE)staining was used to observe the pathological changes in muscle and skin tissues at the trigger point of rats.Immunohistochemistry was used to detect the expression of capsaicin receptor transient receptor potential vanilloid 1(TRPV1)in muscle tissues and interleukin(IL)-33 in skin tissues at the trigger point.The protein expression levels of TRPV1,protein kinase B(Akt),phosphorylated protein kinase B(p-Akt),IL-1β,and tumor necrosis factor-α(TNF-α)in muscle tissues at the trigger point were detected by Western blot.The results showed that as compared with the model group,the mechanical pain threshold and cold pain threshold of rats in other groups were increased after treatment with QFGT.The spontaneous electromyography(EMG)activity was observed in the model group,but QFGT alleviated the EMG activity in a dose-dependent manner.Gait analysis showed that standing duration,average intensity,swing speed,maximum contact point,maximum contact area,paw print length,paw print width,and paw print area were significantly improved in all QFGT groups.Pathological results showed that the disorder of muscle arrangement at the trigger point was decreased,muscle fiber adhesion and atrophy were reduced,and inflammatory cell infiltration was alleviated after treatment with QFGT.In addition,QFGT and HXZT both inhibited the protein expression of TRPV1,PI3K,Akt,p-Akt,IL-1β,and TNF-αin the muscle tissues of rats with MPS.However,there was no significant difference in the pathological structure and expression of IL-33 in the treated skin as compared with the normal group.The related results have proved that QFGT can inhibit the release of inflammatory factors by inhibiting the TRPV1/PI3K/Akt signaling pathway in the muscle trigger point of rats with MPS and finally attenuate the atrophy and adhesion of local muscles and inflammatory infiltration,thereby relieving the muscle pain of rats with MPS,and local administration has no skin irritation.