Endothelial-to-mesenchymal transition (EndMT) is a crucial cellular differentiation process essential for embryonic development and implicated in cardiovascular pathologies such as atherosclerosis and cardiac fibrosis. While soluble factors like transforming growth factor-beta (TGF-β) are established inducers of EndMT, mechanical forces including substrate stiffness, stretch, and shear stress also play key regulatory roles. However, the underlying mechanotransduction mechanisms remain poorly defined. This study examined the role of the mechanosensitive calcium channel TRPV4 in EndMT. Among the two isoforms tested, TGF-β2 proved to be a more potent inducer of EndMT than TGF-β1, promoting the transition of human microvascular endothelial cells (HMEC-1) into a mesenchymal phenotype marked by elevated α-smooth muscle actin (α-SMA) expression and reduced CD31 and VE-cadherin levels. Inhibition of TRPV4 with the selective antagonist GSK2193874 significantly attenuated TGF-β2–induced EndMT. Moreover, TGF-β2 increased TRPV4 protein expression and enhanced TRPV4-mediated calcium influx in response to the agonist GSK1016790A, effects that were blocked by GSK2. Mechanistically, TGF-β2 stimulated Rho (RhoGTP) activation and upregulation of transcription factors Snail, Slug, Twist-1, SIP-1, and ZEB-1. TRPV4 inhibition specifically reduced TGF-β2–induced Rho activation and Snail expression, but not other transcription factors. Finally, pharmacological inhibition of Rho pathway by Rho kinase inhibitor, Y27632 significantly attenuated TGF-β2–induced EndMT. Taken together, these findings identify TRPV4 as a key mediator of TGF-β2–induced EndMT through the Rho/Snail signaling pathway. This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.
Kondapalli et al. (Fri,) studied this question.