Piezo2 is not an indispensable mechanosensor in murine cardiomyocytes

Disruption of the interaction between caveolae and Piezo1 promotes pressure overload-induced cardiac remodeling

Piezo1 channels are activated by mechanical stress and play a significant role in cardiac hypertrophy and fibrosis. However, the molecular mechanisms underlying Piezo1 activation on the cell membrane following pressure overload remain unclear. Caveolae are known to mitigate mechanical forces and regulate Piezo1 function. Therefore, this study aimed to investigate the interaction between caveolae and Piezo1 in the development of pressure overload-induced cardiac remodeling. We observed reduced colocalization between Piezo1 and Caveolin-3 in hypertrophic cardiomyocytes following abdominal aortic constriction and Angiotensin-II treatment, accompanied by increased Piezo1 function and expression. Furthermore, enhanced Piezo1 function was also noted upon caveolae disruption using methyl-beta-cyclodextrin (mβCD). Thus, our findings suggested that pressure overload led to Piezo1 translocation from caveolae, thereby augmenting its function and expression, which may contribute to cardiac remodeling.

Piezo1 Channel as a Potential Target for Hindering Cardiac Fibrotic Remodeling

Fibrotic tissues share many common features with neoplasms where there is an increased stiffness of the extracellular matrix (ECM). In this review, we present recent discoveries related to the role of the mechanosensitive ion channel Piezo1 in several diseases, especially in regulating tumor progression, and how this can be compared with cardiac mechanobiology. Based on recent findings, Piezo1 could be upregulated in cardiac fibroblasts as a consequence of the mechanical stress and pro-inflammatory stimuli that occurs after myocardial injury, and its increased activity could be responsible for a positive feedback loop that leads to fibrosis progression. The increased Piezo1-mediated calcium flow may play an important role in cytoskeleton reorganization since it induces actin stress fibers formation, a well-known characteristic of fibroblast transdifferentiation into the activated myofibroblast. Moreover, Piezo1 activity stimulates ECM and cytokines production, which in turn promotes the phenoconversion of adjacent fibroblasts into new myofibroblasts, enhancing the invasive character. Thus, by assuming the Piezo1 involvement in the activation of intrinsic fibroblasts, recruitment of new myofibroblasts, and uncontrolled excessive ECM production, a new approach to blocking the fibrotic progression can be predicted. Therefore, targeted therapies against Piezo1 could also be beneficial for cardiac fibrosis.