白藜芦醇激活AMPK抑制胶质细胞活化治疗三叉神经痛机制研究

Trigeminal neuralgia is a chronic, relapsing, and remitting condition of disease characterized by paroxysmal and shock hemifacial pain. Although the etiology of the disease is elusive, it has been suggested that robust activated glia, including microglia and astrocyte, plays a key pathogenic role. Inhibition on exceptional activation of glia has been proved effective to relieve trigeminal neuralgia. Thus safe and effective intervention for glial activation is in urgent requirement. Resveratrol, a polyphenol compound from natural products, has been proved to be involved in neuroprotection. Our preliminary results discovered that resveratrol could significantly inhibit trigeminal neuralgia by reducing glia activation and inflammatory factors release, which may be related with the activation of AMPK and the inhibition of MAPK - NFκB signaling pathways. It is reported that AMPK can promote the membrane transfer and opening of KATP channel, and our studies also have proved that opening of KATP channel showed significant analgesic effects by inhibiting neuroinflammation following glial activation. In this study we would further investigate the therapeutic effect of resveratrol for trigeminal neuralgia and its molecular mechanism of glial cell activation.

三叉神经痛是一种常见的慢性疼痛。由于病因和发病机制不明，三叉神经痛的治疗一直是医学界的难题。基础研究提示胶质细胞的异常活化可能在三叉神经痛进程中发挥着重要的作用，抑制胶质细胞的异常活化已经被证明可以有效干预三叉神经痛，但是缺乏一种安全有效的干预措施。白藜芦醇是一种来自于天然产物中的多酚类化合物，具有神经保护作用。我们的预实验结果首次证实白藜芦醇对于三叉神经痛具有良好的治疗作用，且显著性的抑制三叉神经痛进程中胶质细胞的活化；并提示作用机制可能是通过激活AMPK进而抑制 P38/MAPK-NF-κB信号通路而实现。同时有文献报道AMPK可以促进K-ATP通道的膜转位，促进其开放。我们的前期研究也证明K-ATP通道的开放可以显著抑制胶质细胞活化介导的神经炎症，并起到镇痛作用。本基金拟将进一步确认白藜芦醇对于三叉神经痛的治疗性作用，同时深入探讨白藜芦醇抑制胶质细胞活化的分子机制。

本课题围绕着白藜芦醇激活AMPK抑制胶质细胞活化缓解三叉神经痛的机制开展研究。建立大鼠的三叉神经痛慢性缩窄损伤CCI模型，口服给予白藜芦醇，检测白藜芦醇对三叉神经痛的机械痛敏的影响。采用Western blot方法检测大鼠三叉神经脊束核区p-NR1, p-PKC, TNF-α 及 IL1-β蛋白水平的表达，采用免疫荧光方法检测大鼠三叉神经脊束核区CGRP和c-fos的表达，采用Western blot和免疫荧光方法检测胶质细胞的活化，并在在体和离体水平采用Western blot方法检测MAPK的表达变化。结果显示，白藜芦醇可以剂量依赖性地减轻三叉神经痛引起的机械痛敏，抑制三叉神经脊束核c-fos和CGRP的表达上调；白藜芦醇可以抑制三叉神经痛导致的三叉神经脊束核星形胶质细胞和小胶质细胞活化；同时抑制炎症因子IL-1β和TNF-α水平的升高；白藜芦醇通过激活AMPK通路抑制MAPK磷酸化水平表达上调。本实验为AMPK激动剂用于临床治疗三叉神经痛提出了证据，力图为三叉神经痛的治疗提供新的治疗策略，并为研发新的治疗三叉神经痛的药物提供先导化合物。项目资助发表SCI论文2篇。项目投入经费23万元，支出23万元，各项支出基本与预算相符。