炭ET激活了Rac1和RTK信号传递,以诱导F-actin重组和内皮透性
Prashant Jain1,2, Annabel Guichard1,2, Mahtab Moayeri3
1Section of Cell and Developmental Biology, UCSD, La Jolla, CA 92093-0335, USA.
iScience
|October 29, 2025
概括
甲状腺杆菌 (Bacillus anthracis) 毒素 (ET) 通过cAMP信号破坏内皮细胞结构,导致血管崩. 抑制Rac1,PI3K和MEK显示出对炭瘤瘤的治疗潜力.
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 病理生理学 病理生理学
背景情况:
- 甲状腺杆菌 (Bacillus anthracis) 毒素 (ET) 通过增加内皮透气性,导致严重的疾病.
- 当前的治疗方法在释放高剂量的毒素后是无效的.
研究的目的:
- 研究ET诱导的内皮通透性背后的分子机制.
- 为了识别潜在的治疗点炭毒性病.
主要方法:
- 研究了ET对人类大脑微血管内皮细胞 (HBMEC) 的影响.
- 分析了F-actin网络的破坏,Rac1的激活和信号通路 (IGF1R,EGFR,PI3K/AKT,MEK/ERK).
- 使用特定抑制剂的小鼠脚 edem 模型验证的结果.
主要成果:
- 在HBMEC中,ET通过Rac1和cofilin诱导cAMP依赖的F-actin破坏.
- ET迅速激活IGF1R和EGFR,导致PI3K/AKT和MEK/ERK的激活,有助于透性.
- 抑制Rac1,PI3K和MEK的药物可以减少小鼠的ET诱导的.
结论:
- ET通过涉及cAMP,Rac1和受体氨酸激酶的复杂信号级联来破坏内皮质屏障的完整性.
- 准Rac1,PI3K或MEK通路提供了一种有前途的治疗策略来对抗炭瘤.
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