线粒体保护在瑞沙托维减轻奥沙利铂诱导的神经病理性疼痛中的作用

Oxaliplatin (OXA) was widely used to treat advanced colorectal cancer. Howerver, it always induces neuropathic pain (NeP). TLR4 was involved in the regulation of neuropathic pain. However, the roles of TLR4 in OXA-induced neuropathic pain are still unknown. Our raw data show that OXA increases the TLR4 and MyD88 expression in DRG. Both TLR4 gene knockout and resatorvid (TAK242; a TLR4 inhibitor) attenuate the OXA-induced neuropathic pain. TAK242 suppresses the OXA-induced the expression of ATF3 (a marker of neuron injury) and TRPA1. In addition, TAK242 can attenuate the OXA-induced neuron growth inhibition. Mitochondia injury can induced the neuropathic pain. Our raw data also show that TAK242 can reduce the OXA-induced mitochondia ultrostructure injury of DRG neuron. The aims of project are to investigate the effects of OXA and TAK242 on the mitochondria function, such as the mitochondria DNA damage, ATP level and mitochodrial membrane potential and so on.Through which, explores the attenuation of TAK242 in OXA induced neuropathic pain by the protection of dorsal root ganglion neuron mitochondria and related mechanisms. In addition, the effects of TAK242 on TRPA1 inward currents and intracellular Ca2+ level which are also investigated. The results would provide the crucial clues for the clinical treat of OXA-induced neuropathic pain.

奥沙利铂（OXA）治疗肿瘤时会诱发神经病理性疼（NeP）。TLR4与NeP密切相关，但它在OXA诱导的NeP中的作用和机理还不清楚。我们发现: OXA可促进DRG中TLR4和MyD88表达；TLR4基因敲除和瑞沙托维（TAK242；TLR4抑制剂）都可减轻OXA诱导的NeP；TAK242可抑制OXA诱导的DRG中 ATF3（神经元损伤标志物）和TRPA1表达。此外，TAK242可抑制OXA诱导的神经元生长抑制。线粒体损伤可诱发NeP，我们发现，TAK242可抑制OXA诱导的神经元线粒体结构损伤。本项目拟研究TAK242和OXA对线粒体功能，如对MtDNA，ATP和线粒体膜电位等的影响，探索TAk242通过保护线粒体减轻NeP及其机理。利用细胞培养，研究TAk242对TRPA1内向电流及胞内Ca2+水平的影响。进一步阐述线粒体损伤与电生理的关系。结果对OXA诱导的NeP临床治疗具有重要意义。

奥沙利铂（OXA）临床常用于化疗消化道肿瘤，但它会产生很强的副作用，包括神经病理性疼痛。本项目研究探索了TLR4信号在奥沙利铂诱导的神经病理性疼痛中的作用及相关机理。研究发现：（1）TLR4基因敲除可以减轻OXA诱导的神经病理性疼痛；（2）TLR4基因敲除可以降低ATF3在神经病理性痛中背根神经节神经元细胞的免疫反应性；（3）TLR4基因敲除减轻奥沙利铂所诱导DRG神经元线粒体形状改变，对线粒体结构具有保护作用；（4）TLR4基因敲除减轻奥沙利铂诱导背根神经节中Cytochrome C、BAX、Caspase-3、Casepase-9、Cleaved caspase-9的蛋白质过表达；（5）TLR4基因敲除减轻奥沙利铂诱导的背根神经节中BAX、Cytochrome C、Casepase-9、Caspase-3等mRNA的过表达；（6）TLR4基因敲除减轻奥沙利铂诱导的背根神经节中MyD88、FADD、Caspase-8等mRNA的过表达；（7）TLR4基因敲除减轻奥沙利铂诱导的背根神经节中对p-DRP 1的抑制，同时减轻FIS 1的过表达；（8）TLR4基因敲除减轻奥沙利铂诱导的背根神经节中Cytochrome C、Bax、Caspase-3的免疫反应性；（9）在本项目的支持下，还对坐骨神经结扎诱导的神经病理性疼痛和肿瘤的发生开展了一系列的研究。研究结果表明，TLR4信号参与了奥沙利铂诱导的神经病理疼痛，其机制涉及线粒体保护。研究结果对增强OXA对食管癌的治疗效果，减少剂量、减轻其毒副作用具有重要的临床意义。