Piezo1 inhibitor isoquercitrin rescues neural impairment mediated by NLRP3 after intracerebral hemorrhage.

In intracerebral hemorrhage (ICH), the mechanical brain injury is a considerable and indispensable factor determining the neurological functions and poor outcomes. Previous studies indicate the mechanically gated ion channel-Piezo1 can transduce mechanical effects following ICH. Isoquercitrin (ISQ) is a well-studied ion channel inhibitor. Furthermore, whether the following Piezo1-mediated neurological impairment can be ameliorated by ISQ remains unclear. Herein, we constructed the hydrostatic pressure model and ICH rat model. Firstly, we found that Piezo1 agonists Yoda1 and Jedi1 facilitated extracellular calcium influx dramatically, but ISQ could depress intracellular Ca overload under hydrostatic pressure in primary neurons. Then we detected the expression profile of Piezo1, NLRP3 and NF-κB p-p65 after ICH, and found that the expression of Piezo1 was much earlier than NLRP3 and NF-κB p-p65. Furthermore, by western blot and immunofluorescence, ISQ decreased the expression of Piezo1 and NLRP3 dramatically like GsMTx4, but Nigericin as a NLRP3 agonist failed to affect Piezo1. Besides, both ISQ and interfering Piezo1 suppressed the upregulated caspase-1, NF-κB p-p65, p-IκBα, Tunel-positive cells and inflammatory factors (IL-1β, IL-6 and TNF-α) in ICH. At last, the hydrostatic pressure or hematoma induced disturbed neural viability, disordered neural cytomorphology, and increased neurobehavioral and cognitive deficits, but they were improved by ISQ and GsMTx4 strongly. Therefore, ISQ could alleviate neurological injuries induced by Piezo1 via NLRP3 pathway. These observations indicated that Piezos might be the new therapeutic targets, and blocking Piezos/NLRP3 pathway by ISQ could be an auspicious strategy for the treatment of ICH.