肝星状细胞细胞外囊中的普罗林诱导了血小板依赖的血栓的形成和释放的profibroticTGF-β
Rui Chen1, Emily Huang2, Xianfang Wu3
1Department of Cardiovascular & Metabolic Sciences, Cleveland Clinic Research, Cleveland Clinic, Cleveland, Ohio, USA.
概括
肝星细胞 (HSCs) 释放细胞外囊泡 (EVs),通过prorenin激活血小板,从而启动肝纤维化. 这种新发现的途径突出显示了肝病进展中的HSC-EVs和prorenin.
科学领域:
- 肝病学 肝病学是一种肝病学.
- 血液学 血液学 血液学
- 细胞生物学 细胞生物学
背景情况:
- 失调的凝血和血小板激活与肝功能障碍和纤维化有关.
- 在肝脏中引发这些事件的确切机制尚不清楚.
- 肝星细胞 (HSC) 在肝纤维化中起着至关重要的作用.
研究的目的:
- 阐明HSCs调解血小板激活并导致肝纤维化的机制.
- 在肝损伤的背景下,确定连接肝细胞,血小板和凝血的新途径.
主要方法:
- 在小鼠中使用康卡纳瓦林A (ConA) 诱导的肝炎模型.
- 对血小板激活标记物的分析 (P-选择素).
- 来自HSC的细胞外囊泡 (EVs) 的表征.
- 酵素测定,抑制剂研究 (佩普斯塔丁,阿利斯基伦,VTP23999),siRNA对前列宁的淘汰.
- 免疫组织化学,qPCR,西部涂抹.
- 对凝血级联激活和TGF-β信号的评估.
主要成果:
- 康纳治疗激活了常存血小板,并诱导了肝纤维化.
- 来自HSC的EV刺激了血小板聚合,独立于已知的激动剂.
- HSC-EV含有与表面相关的前林素,该前林素通过前林素受体激活血小板.
- 这种相互作用触发了凝血级联,血栓生成和TGF-β释放.
- TGF-β激活HSCs,促进蛋白质表达.
结论:
- 通过prorenin确定了一种通过HSC-EV介导的血小板激活的新途径.
- 由HSC-EVs进行的肝脏内血小板激活有助于血栓形成和纤维蛋白沉积.
- 这一发现揭示了肝纤维化病变的新机制.
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