Piezo1 acts upstream of TRPV4 to induce pathological changes in endothelial cells due to shear stress

Abstract

The ion channels Piezo1 and TRPV4 have both, independently, been implicated in high venous pressure– and fluid shear stress–induced vascular hyperpermeability in endothelial cells. However, the mechanism by which Piezo1 and TRPV4 channels execute the same function is poorly understood. Here we demonstrate that Piezo1 regulates TRPV4 channel activation in endothelial cells and that Piezo1-mediated TRPV4 channel opening is a function of the strength and duration of fluid shear stress. We first confirmed that either fluid shear stress or the Piezo1 agonist, Yoda1, led to an elevation in intracellular calcium ([Ca 2+ ] i ) and that application of the Piezo1 antagonist, GsMTx4, completely blocked this change. We discovered that high and prolonged shear stress caused sustained [Ca 2+ ] i elevation that was blocked by inhibition of TRPV4 channel opening. Moreover, Piezo1 stimulated TRPV4 opening through activation of phospholipase A2. TRPV4-dependent sustained [Ca 2+ ] i elevation was responsible for fluid shear stress–mediated and Piezo1-mediated disruption of adherens junctions and actin remodeling. Blockade of TRPV4 channels with the selective TRPV4 blocker, HC067047, prevented the loss of endothelial cell integrity and actin disruption induced by Yoda1 or shear stress and prevented Piezo1-induced monocyte adhesion to endothelial cell monolayers. These findings demonstrate that Piezo1 activation by fluid shear stress initiates a calcium signal that causes TRPV4 opening, which in turn is responsible for the sustained phase calcium elevation that triggers pathological events in endothelial cells. Thus, deleterious effects of shear stress are initiated by Piezo1 but require TRPV4.

Role of Vascular Smooth Muscle Cell Phenotype Switching in Arteriogenesis

“…Other early responses led to mechanically gated channels such as transient receptor potential cation channel V4 (TRPV4) and Piezo1. These are sensitive to changes in the endothelial cell membrane’s tension resulting from fluid shear stress [ 109 ].…”

Computational and experimental studies of a cell-imprinted-based integrated microfluidic device for biomedical applications

“…Recently shear stresses at physiological (≤ 5 dyne/cm 2 ) and pathological levels were used to determine the amount and duration of shear stress forces that influenced [Ca 2+ ] i in HUVECs. A force of 12 dyne/cm 2 applied for 1 min resulted in a sustained increase in [Ca 2+ ] i , while the same force applied for 1 or 5 s, or lower shear stress (4 dyne/cm 2 ) for 1 min was not enough to induce a sustained increase in [Ca 2+ ] i and resulted in just a transient increase 70 .…”

“…TRPV4 and Piezo1 are non-selective calcium-permeable ion channels that can be activated by mechanical stimuli such as compression, hydrostatic pressure, or fluid flow (i.e., shear stress). TRPV4 is thought to operate as a signal transducer that responds to shear stress [68][69][70][71][72] . Shear stress regulates intracellular calcium [Ca 2+ ] i in endothelial cells.…”

Channelling the Force to Reprogram the Matrix: Mechanosensitive Ion Channels in Cardiac Fibroblasts

“…Some of these effects may be due to TRPV4 acting downstream of other mechanosensitive channels, such as Piezo1 (see Section 3) [77,172]. For example, Swain and colleagues reported that Piezo1 and TRPV4 act in concert to initiate and sustain Ca 2+ influx in response to mechanical stimulation in human pancreatic acinar cells [77] and in response to shear fluid stress in human EC [172], with activation of Piezo1 prompting TRPV4 activity.…”

“…Some of these effects may be due to TRPV4 acting downstream of other mechanosensitive channels, such as Piezo1 (see Section 3) [77,172]. For example, Swain and colleagues reported that Piezo1 and TRPV4 act in concert to initiate and sustain Ca 2+ influx in response to mechanical stimulation in human pancreatic acinar cells [77] and in response to shear fluid stress in human EC [172], with activation of Piezo1 prompting TRPV4 activity. TRPV4 knockdown also diminished Piezo1 sensitivity to Piezo1-specific agonists [77], thus indicating that the channels may act in concert to confer mechanical signalling, with Piezo1 acting as the mechanical force sensor [77,172].…”