夹脊电针调控NLRP3信号通路改善急性脊髓损伤大鼠炎症损伤的作用及机制

Jiaji Electroacupuncture can promote the reconstruction of motor function after acute spinal cord injury, but the mechanism is still not clear. Our previous studies proved that Jiaji Electroacupuncture could regulate the microenvironment and reduce the secondary injury after acute spinal cord injury. It has been demonstrated that NLRP3 inflammatory bodies could mediate the inflammatory response after acute spinal cord injury. We speculate that："Jiaji Electroacupuncture can regulate the expression of P2X7R after acute spinal cord injury, remove ONOO- in injured tissue, inhibit the activation of NLRP3 inflammatory bodies, so as to reduce the inflammatory injury". ONOO- scavenger was used in acute SCI rats, and the expression of P2X7R and NLRP3 was interfered by siRNA. The expression of NLRP3 signaling pathway related proteins and genes after acute spinal cord injury was studied from the aspects of morphology, behavior and molecular biology. To explore the mechanism of Jiaji Electroacupuncture improves inflammatory injury through NLRP3 Signaling Pathway after acute spinal cord injury and to provide theoretical basis for its clinical application.

夹脊电针能促进急性脊髓损伤后运动功能重建，但其作用机制仍不明确。前期我们发现夹脊电针能调控微环境，降低急性脊髓损伤后继发性损伤。有研究证实NLRP3炎性体介导了急性脊髓损伤后炎症反应。我们推测：“夹脊电针能调控急性脊髓损伤后P2X7R表达，清除损伤组织中ONOO-，抑制NLRP3炎症小体活化,改善炎症损伤”。在急性脊髓损伤大鼠模型上，引入ONOO-清除剂，采用siRNA干扰P2X7R、NLRP3的表达，从形态学、行为学、分子生物学等角度，研究急性脊髓损伤以及夹脊电针干预后NLRP3信号通路相关蛋白及基因的表达，探索夹脊电针调控NLRP3信号通路改善急性脊髓损伤炎症损伤的作用机制，为临床应用提供理论基础。

急性脊髓损伤（ASCI）是临床常见病，由于致病的突发性和严重性，导致其致死率和致残率极高。急性脊髓损伤后大量以炎症细胞介导的炎症反应导致各种细胞功能改变，加重残存神经细胞的死亡，因此对ASCI继发性炎症损伤进行干预并促进神经功能修复是我们关注的焦点。本研究通过建立急性脊髓损伤大鼠模型，采用夹脊电针治疗，观察夹脊电针对NLRP3炎症体信号通路及相关因子表达的影响，结果表明：（1）夹脊电针能够下调P2X7R、NLRP3、ASC、Caspase-1、IL-1β、IL-18的表达，改善炎症损伤，促进急性脊髓损伤大鼠运动功能恢复，减轻脊髓继发性损伤，并且治疗时间越长，优势越明显。（2）夹脊电针能够减少脊髓损伤大鼠脊髓组织炎性细胞数量，增加神经细胞数量，改善脊髓组织炎性细胞浸润状态。（3）质粒病毒装载siRNA干扰了P2X7R表达，降低NLRP3mRNA分子水平，抑制NLRP3蛋白及基因在小胶质细胞中的表达，减少促炎因子的分泌，改善SCI大鼠脊髓组织炎性损伤。（4）夹脊电针能通过调控P2X7R，抑制NLRP3蛋白及基因在小胶质细胞中的表达，进而减少促炎因子的分泌，改善SCI大鼠脊髓组织炎性损伤。（5）质粒病毒装载siRNA干扰了NLRP3表达，降低NLRP3mRNA分子水平，抑制NLRP3蛋白在小胶质细胞中表达，减少促炎因子的分泌，改善SCI大鼠脊髓组织炎性损伤。（6）夹脊电针可能通过调控P2X7R，抑制NLRP3、cleaved caspase-1、IL-1β和IL-18阳性细胞的表达，进而减少促炎因子的分泌，改善SCI大鼠脊髓组织炎性损伤。（7）夹脊电针能通过抑制脊髓损伤大鼠脊髓组织膜受体P2X7R，降低NLRP3炎症小体激活的启动，降低急性脊髓损伤炎性损伤。（8）夹脊电针能通过调控脊髓损伤大鼠脊髓组织P2X7R表达，清除NOX2、iNOS依赖的 ONOO¯，抑制 NLRP3炎症小体激活的启动，抑制炎性因子IL-1β、IL-18的表达激活，改善炎性损伤，抑制小胶质细胞激活。本研究从行为学、形态学、分子生物学等角度，阐明了夹脊电针干预急性脊髓损伤NLRP3信号通路相关蛋白及基因的表达，揭示了夹脊电针调控NLRP3信号通路、改善急性脊髓损伤作用机制，为夹脊电针治疗脊髓损伤的临床应用做出了重要支撑。