PERK-p38 MAPK轴驱动福克斯内皮角膜缩症中的内质网膜压力诱导的亡
Takako Onishi1, Taichi Yuasa1, Naoyuki Ueda1
1Department of Biomedical Engineering, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan.
Investigative ophthalmology & visual science
|August 26, 2025
概括
由于内质网膜 (ER) 的压力,p38 MAPK是Fuchs内皮角膜缩 (FECD) 细胞死亡的关键媒介. 通过减少细胞死亡,抑制p38MAPK显示了FECD的治疗潜力.
科学领域:
- 眼科 眼科
- 细胞生物学
- 分子生物学
背景情况:
- 福克斯内皮角膜缩症 (FECD) 涉及到角膜内皮细胞死亡.
- 细胞内膜网 (ER) 的压力与FECD的发病有关.
- 在FECD中,p38基因激活蛋白激酶 (MAPK) 在ER压力诱导的细胞死亡中的作用尚不完全理解.
研究的目的:
- 调查p38 MAPK在FECD中引起的角膜内皮细胞死亡中的作用.
- 评估p38 MAPK作为FECD的潜在治疗点.
主要方法:
- 使用了三种ER应激模型:TGF-β的FECD患者衍生细胞,thapsigargin的正常角膜内皮细胞和MG-132的iHCEC.
- 使用特定抑制剂 (SB203580,PH-797804,VX-702) 调节p38 MAPK活动.
- 评估了PERK-eIF2α-ATF4-CHOP通路的激活,p38 MAPK酸化,线粒体功能,以及通过西部抹杀,免疫光和流细胞测量进行的细胞灭亡.
主要成果:
- 在所有模型中,MAPK激活是PERK- eIF2α酸化的下游和ATF4- CHOP诱导的上游.
- 在iFECD/ TGF-β和其他ER压力模型中,MAPK抑制阻止了CHOP上调,维护了线粒体功能,并减少了亡.
- 在机理上,PERK knockdown抑制了p38 MAPK的激活,但p38 MAPK的抑制没有影响PERK的激活,从而建立了等级关系.
结论:
- 在角膜内皮细胞中,p38 MAPK 是 ER 应激诱导的亡的关键调解者.
- p38 MAPK 作为适应性和亲细胞解折蛋白响应 (UPR) 信号传递之间的分子切换.
- p38 MAPK 抑制剂表现出细胞保护功效,这表明FECD的治疗潜力.
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