Targeting PIEZO1-TMEM16F Coupling to Mitigate Sickle Cell Disease Complications

Abstract

A deeper understanding of sickle cell disease (SCD) pathophysiology is critical for identifying novel therapeutic targets. A hallmark of SCD is abnormal phosphatidylserine (PS) exposure on sickle red blood cells (RBCs), which contributes to anemia, thrombosis, and vaso-occlusive crises (VOC). However, the mechanisms underlying this excessive PS exposure remain unclear. Here, we identify TMEM16F, a Ca²⁺-activated lipid scramblase, as a key mediator of PS exposure downstream of Ca²⁺ influx through the mechanosensitive channel PIEZO1 in sickle RBCs. Electrophysiology, imaging, and flow cytometry reveal that deoxygenation-induced sickling activates PIEZO1, triggering Ca²⁺ entry, TMEM16F activation, and PS exposure. This cascade promotes PS⁺ microparticle release, thrombin generation, and RBC adhesion to endothelial cells. Notably, partial PIEZO1 inhibition with benzbromarone, an anti-gout drug, suppresses these effects. Our findings define a previously unrecognized mechanotransduction pathway in sickle RBCs and propose a unique therapeutic strategy to mitigate hypercoagulability and vaso-occlusion associated with SCD.