中国神经再生研究(英文版) ›› 2018, Vol. 13 ›› Issue (2): 252-256.doi: 10.4103/1673-5374.226394

• 原著:脑损伤修复保护与再生 • 上一篇    下一篇

受体相互作用蛋白激酶3依赖性程序性坏死抑制剂达拉菲尼减轻缺血性脑损伤

  

  • 收稿日期:2017-11-10 出版日期:2018-02-15 发布日期:2018-02-15
  • 基金资助:

    加拿大心脏和卒中基金;加拿大健研究所基金

Dabrafenib, an inhibitor of RIP3 kinase-dependent necroptosis, reduces ischemic brain injury

Shelly A. Cruz1, 2, 4, Zhaohong Qin1, 4, Alexandre F. R. Stewart3, Hsiao-Huei Chen1, 2, 4   

  1. 1 Ottawa Hospital Research Institute, Ottawa, Canada
    2 University of Ottawa, Brain and Mind Institute, Ottawa, Canada
    3 University of Ottawa Heart Institute, Ottawa, Canada
    4 Canadian Partnership for Storke Recovery, Ottawa, Canada
  • Received:2017-11-10 Online:2018-02-15 Published:2018-02-15
  • Contact: Hsiao-Huei Chen, Ph.D.,hchen@uottawa.ca.
  • Supported by:

    This study was supported by grants from the Heart and Stroke Foundation of Canada (HHC, AFRS), the Canadian Institutes of Health Research (to HHC and AFRS). HHC was also supported by a Mid-Career Investigator Award from the Heart and Stroke Foundation of Ontario.

摘要:

缺血性脑损伤通过激活caspase诱导细胞凋亡和激活肿瘤坏死因子/死亡受体相关的受体相互作用蛋白激酶(RIPK)促进坏死性细胞死亡,从而触发神经元死亡。最近的证据显示RIPK抑制剂已在缺血性脑损伤动物模型中证实了其具有神经保护性,但这一点还未经临床试验证实。目前主要用于治疗黑色素瘤的达拉菲尼是一种在微摩尔浓度下的强效RIPK3抑制剂。为验证达拉菲尼是否对光化学诱导的缺血性脑损伤有神经保护作用,实验以光栓法诱导C57BL6小鼠大脑局部缺血后1h,以10mg / kg剂量腹腔注射达拉菲尼,发现给药后第2天,小鼠的大脑梗死体积明显减小,同时定量PCR检测到上调的大脑肿瘤坏死因子αmRNA表达明显受到抑制。说明达拉菲尼神经保护作用与减轻缺血脑组织局部炎症反应有关。然而,接下来的较低剂量(5mg/kg )达拉菲尼干预在4天后未能维持这种神经保护作用,说明5mg/kg的维持剂量不足以维持其神经保护的发挥。为检测达布非尼对巨噬细胞中肿瘤坏死因子a激活的影响,用10μmol/L的达拉菲尼干预100ng/mL脂多糖刺激/未刺激的骨髓来源巨噬细胞,发现达拉菲尼可减弱脂多糖诱导的骨髓来源巨噬细胞中肿瘤坏死因子α的活化。表明达拉菲尼可在局部脑缺血后减弱肿瘤坏死因子α诱导的神经元坏死程序,从而提示其有在临床上应用于缺血性脑卒中治疗的潜力。

orcid:0000-0003-2914-6057(Hsiao-Huei Chen)

 

关键词: 神经再生, 缺血性脑损伤, 炎症, 巨噬细胞, 达拉菲尼, 肿瘤坏死因子&alpha, 光化学, 受体相互作用蛋白激酶, 程序性坏死, 小胶质细胞, 脑卒中

Abstract:

Ischemic brain injury triggers neuronal cell death by apoptosis via caspase activation and by necroptosis through activation of the receptor-interacting protein kinases (RIPK) associated with the tumor necrosis factor-alpha (TNF-α)/death receptor. Recent evidence shows RIPK inhibitors are neuroprotective and alleviate ischemic brain injury in a number of animal models, however, most have not yet undergone clinical trials and safety in humans remains in question. Dabrafenib, originally identified as a B-raf inhibitor that is currently used to treat melanoma, was later revealed to be a potent RIPK3 inhibitor at micromolar concentrations.Here, we investigated whether Dabrafenib would show a similar neuroprotective effect in mice subjected to ischemic brain injury by photothrombosis. Dabrafenib administered intraperitoneally at 10 mg/kg one hour after photothrombosis-induced focal ischemic injury significantly reduced infarct lesion size in C57BL6 mice the following day, accompanied by a markedly attenuated upregulation of TNF-α. However,subsequent lower doses (5 mg/kg/day) failed to sustain this neuroprotective effect after 4 days. Dabrafenib blocked lipopolysaccharides-induced activation of TNF-α in bone marrow-derived macrophages, suggesting that Dabrafenib may attenuate TNF-α-induced necroptotic pathway after ischemic brain injury. Since Dabrafenib is already in clinical use for the treatment of melanoma, it might be repurposed for stroke therapy.

Key words: ischemic brain injury, inflammation, macrophage, Dabrafenib, tumor necrosis factor-alpha, photothrombosis, receptor-interacting protein kinases, necroptosis, microglia, stroke, neural regeneration