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bioRxiv · 10.1101/2020.07.16.207589

Piezo1 potentially mediates inflammation in balloon-inflated rat brain and its bidirectional mechanosensitivity

Abstract

Brain injury after intracerebral hemorrhage is extremely complicated, and the exact mechanism remains puzzling. Piezo1, a novel mammalian mechanosensitive ion channel, has been identified to play important roles in several pathologic and physiologic procedures that involve cellular mechanotransduction. However, the role of Piezo1 in hematoma compression after intracerebral hemorrhage is still unclear. In the present study, we established a balloon-inflated rat brain model mimicking the pure mechanical compression of a hematoma and detected balloon compression in the basal ganglia region of the brain, resulting in abnormal behaviors and a significant increase in the expression of Piezo1 and proinflammatory cytokines. These effects were reversed by GsMTx4, an antagonist of Piezo1. Additionally, the balloon deflation time affected behavioral function and the levels of Piezo1 and proinflammatory cytokines. These results establish the first in vivo evidence for the role of Piezo1 in blood-brain neuroinflammation after hematoma compression. Piezo1 may therefore be a potential therapeutic target for the treatment of intracerebral hemorrhage.

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Zhang, Y., Wang, G., Xie, M., Lian, L., Xiong, Y., Xu, F., Li, G., Tang, Z., Wang, F., Zhu, S.. 2020-07-17. Piezo1 potentially mediates inflammation in balloon-inflated rat brain and its bidirectional mechanosensitivity. https://doi.org/10.1101/2020.07.16.207589

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