Wnt3a信号通路通过JMJD6的表观遗传修饰参与神经病理性疼痛

目的：探讨Wnt3a通过Jumonji C结构域6( Jumonji C domain 6，JMJD6)的表观遗传修饰在神经病理性疼痛中发挥作用的机制。方法：将SD大鼠分为4组：Sham组，慢性缩窄性损伤(chronic constriction injury，CCI)组，CCI+阴性慢病毒表达载体(LV-NC)组；CCI+慢病毒过表达载体(LV-JMJD6)组。构建SD大鼠坐骨神经CCI模型和JMJD6慢病毒表达载体。CCI术后第3天通过鞘内导管给药，按照分组分别给予生理盐水和含慢病毒的试剂(病毒滴度1×108 TU/mL)各20 μL。监测大鼠的机械缩足阈值(paw withdrawal mechanical threshold，PWMT)和热缩足潜伏期(paw withdrawal thermal latency，PWTL)，并运用蛋白质印迹法检测脊髓水平Wnt3a及NR2B蛋白的表达变化，免疫共沉淀检测JMJD6与Wnt3a之间是否存在直接相互作用。结果：与Sham组相比，CCI术后各组大鼠的PWMT明显降低和PWTL明显缩短(P<0.05)。与CCI组和CCI+LV-NC组相比，CCI+LV-JMJD6组的PWMT在术后第10和14天明显升高，PWTL在术后第14天明显延长(P<0.05)。CCI术后第14天，CCI组及CCI+LV-NC组Wnt3a和NR2B蛋白表达水平较Sham组明显升高，鞘内注射慢病毒载体后， CCI+LV-JMJD6组的Wnt3a和NR2B蛋白表达水平较CCI+LV-NC组降低(P<0.05)。免疫共沉淀结果显示Wnt3a与JMJD6之间无直接相互作用。结论：Wnt3a参与调节神经病理性疼痛，其作用可能与JMJD6的表观遗传修饰相关，两者可能通过间接相互作用进行调节。

Wnt3a signaling pathway plays a role in neuropathic pain through epigenetic modification of JMJD6

Objective: To explore whether Wnt3a exerts a role in neuropathic pain through Jumonji C domain 6(JMJD6)-associated epigenetic modification.Methods: SD rats were divided into 4 groups: A sham group, a chronic constriction injury(CCI) group, a CCI+negative lentiviral expression vector (LV-NC) group and a CCI+lentiviral overexpression vector (LV-JMJD6) group. The sciatic nerve CCI model of SD rat and JMJD6lentiviral expression vector were constructed. On the third day after CCI, the intrathecal catheter wasprepared, and 20 μL of normal saline and lentivirus-containing reagent (virus titer 1×108 TU/mL)were administered. The rats’ paw withdrawal mechanical threshold (PWMT) and paw withdrawalthermal latency (PWTL) were monitored, and Western blotting was used to detect the expressionof Wnt3a and NR2B protein in the spinal cord. Co-immunoprecipitation was applied to detect theinteraction between JMJD6 and Wnt3a.Results: Compared with the sham group, the PWMT of the rats in each group after CCI wassignificantly decreased and the PWTL was significantly shortened (P<0.05). Compared withthe CCI group and the CCI+LV-NC group, PWMT in the CCI+LV-JMJD6 group was increasedsignificantly on the 10th day and the 14th day after CCI, and the PWTL was significantly prolongedon the 14th day after CCI (P<0.05). On the 14th day after CCI, the expression levels of Wnt3a andNR2B in the CCI group and the CCI+LV-NC group were significantly higher than those in thesham group. After intrathecal injection of lentiviral vector, Wnt3a and NR2B protein expressionlevels in the CCI+LV-JMJD6 group were lower compared with the CCI+LV-NC group (P<0.05).The results of co-immunoprecipitation showed no direct interaction between Wnt3a and JMJD6.Conclusion: Wnt3a is involved in mediating neuropathic pain, and its effect may be related to theepigenetic modification of JMJD6, which is likely regulated through indirect interaction.