METHODS: A chronic constriction injury (CCI) model was developed to simulate neuralgia in vivo. We overexpressed or knocked down TRAF6 in CCI mice, respectively. Activation of microglia by TRAF6, the inflammatory response, and disease progression were inspected using WB, qRT-PCR, immunofluorescence, flow cytometry, and ELISA assays. Moreover, the mechanism of M1/M2 polarization activation of microglia by TRAF6 was elaborated in BV-2 cells.
RESULTS: TRAF6 was enhanced in the spinal neurons and microglia of the CCI mice model compared with the sham operation group.. Down-regulation of TRAF6 rescued the expression of Iba-1. In response to mechanical and thermal stimulation, PWT and PWL were improved after the knockdown of TRAF6. Decreased levels of pro-inflammatory factors were observed in TRAF6 knockdown groups. Meanwhile, increased microglial M1 markers induced by CCI were limited in mice with TRAF6 knockdown. In addition, TRAF6 overexpression has the precise opposite effect on CCI mice or microglia polarization. We also identifed that TRAF6 activated the c-JUN/NF-kB pathway signaling; the inhibitor of c-JUN/NF-kB could effectively alleviate the neuropathic pain induced by upregulated TRAF6 in the CCI mice model.
CONCLUSIONS: In summary, this study indicated that TRAF6 was concerned with neuropathic pain, and targeting the TRAF6/c-JUN/NF-kB pathway may be a prospective target for treating neuropathic pain.
方法:开发了一种慢性压迫性损伤(CCI)模型来模拟体内神经痛。我们在CCI小鼠中过度表达或敲低TRAF6,分别。TRAF6对小胶质细胞的活化,炎症反应,并使用WB检查疾病进展,qRT-PCR,免疫荧光,流式细胞术,和ELISA测定。此外,在BV-2细胞中,阐述了TRAF6对小胶质细胞M1/M2极化激活的机制。
结果:与假手术组相比,CCI小鼠模型的脊髓神经元和小胶质细胞中的TRAF6增强。.TRAF6的下调拯救了Iba-1的表达。为了响应机械和热刺激,TRAF6敲低后PWT和PWL均有改善。TRAF6敲低组的促炎因子水平降低。同时,在TRAF6敲低的小鼠中,CCI诱导的小胶质细胞M1标记增加受到限制。此外,TRAF6过表达对CCI小鼠或小胶质细胞极化具有精确相反的作用。我们还确定TRAF6激活了c-JUN/NF-kB通路信号;c-JUN/NF-kB的抑制剂可以有效缓解CCI小鼠模型中TRAF6上调引起的神经病理性疼痛。
结论:总之,这项研究表明,TRAF6与神经性疼痛有关,靶向TRAF6/c-JUN/NF-kB途径可能是治疗神经性疼痛的前瞻性靶点。