Liu Lei, Zhang Qiongling, Xiao Shunli, Sun Zhengxiao, Ding Shilan, Chen Ying, Wang Lan, Yin Xiaojie, Liao Fulong, Jiang Lin-Hua, Xue Mei, You Yun
Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China.
Sino-UK Joint Laboratory of Brain Function and Injury, Xinxiang Medical University, Xinxiang, China.
Front Pharmacol. 2021 Mar 22;12:606245. doi: 10.3389/fphar.2021.606245. eCollection 2021.
XueShuanTong (XST) comprising therapeutically active ginsenosides, a lyophilized extract of roots, is extensively used in traditional Chinese medicine to treat ischemic heart and cerebrovascular diseases. Our recent study shows that treatment with XST inhibits shear-induced thrombosis formation but the underlying mechanism remained unclear. This study aimed to investigate the hypothesis that XST inhibited shear-induced platelet aggregation via targeting the mechanosensitive Ca-permeable Piezo1 channel by performing platelet aggregation assay, Ca imaging and Western blotting analysis. Exposure to shear at physiologically (1,000-2000 s) and pathologically related rates (4,000-6,000 s) induced platelet aggregation that was inhibited by treatment with GsMTx-4. Exposure to shear evoked robust Ca responses in platelets that were inhibited by treatment with GsMTx-4 and conversely enhanced by treatment with Yoda1. Treatment with XST at a clinically relevant concentration (0.15 g L) potently inhibited shear-induced Ca responses and platelet aggregation, without altering vWF-mediated platelet adhesion and rolling. Exposure to shear, while resulting in no effect on the calpain-2 expression in platelets, induced calpain-2-mediated cleavage of talin1 protein, which is known to be critical for platelet activation. Shear-induced activation of calpain-2 and cleavage of talin1 were attenuated by treatment with XST. Taken together, our results suggest that XST inhibits shear-induced platelet aggregation via targeting the Piezo1 channel to prevent Piezo1-mediated Ca signaling and downstream calpain-2 and talin1 signal pathway, thus providing novel insights into the mechanism of the therapeutic action of XST on platelet aggregation and thrombosis formation.
血栓通（XST）由具有治疗活性的人参皂苷组成，是一种根的冻干提取物，在传统中医中广泛用于治疗缺血性心脏病和脑血管疾病。我们最近的研究表明，XST治疗可抑制剪切诱导的血栓形成，但其潜在机制仍不清楚。本研究旨在通过进行血小板聚集试验、钙成像和蛋白质印迹分析，探讨XST通过靶向机械敏感的钙通透Piezo1通道抑制剪切诱导的血小板聚集这一假说。在生理（1000 - 2000秒）和病理相关速率（4000 - 6000秒）下暴露于剪切力会诱导血小板聚集，而GsMTx - 4处理可抑制这种聚集。暴露于剪切力会在血小板中引发强烈的钙反应，GsMTx - 4处理可抑制这种反应，而Yoda1处理则会增强这种反应。以临床相关浓度（0.15 g/L）的XST处理可有效抑制剪切诱导的钙反应和血小板聚集，而不会改变血管性血友病因子（vWF）介导的血小板黏附和滚动。暴露于剪切力虽然对血小板中钙蛋白酶 - 2的表达没有影响，但会诱导钙蛋白酶 - 2介导的踝蛋白1蛋白的裂解，已知踝蛋白1对血小板激活至关重要。XST处理可减弱剪切诱导的钙蛋白酶 - 2激活和踝蛋白1的裂解。综上所述，我们的结果表明，XST通过靶向Piezo1通道来抑制剪切诱导的血小板聚集，以防止Piezo1介导的钙信号传导以及下游的钙蛋白酶 - 2和踝蛋白1信号通路，从而为XST对血小板聚集和血栓形成的治疗作用机制提供了新的见解。
