The Role of the Mechanorezeptor Piezo2 in Cardiac Mechanosensation

Objectives: Mechanosensation and mechanotransduction belong to the most fundamental processes in biology. Especially, in the cardiovascular system, a mechanosensitive feedback mechanism is essential to adapt to different physiological demands. Although it plays such an important part, there is little knowledge about it. Piezo2 is a mechanosensitive ion channel and has a role in rapidly adapting mechanically activated currents in somatosensory neurons. Its expression in cardiac tissue is low but stable detectable.

Methods: We analyzed Piezo2 expression in cardiac tissue of mice after transverse aortic constriction (TAC) and after continuous angiotensin II infusion. Both are commonly used models for pressure-induced cardiac hypertrophy and heart failure. The control group had sham surgery, respectively, continuous sodium chloride infusion. Furthermore, we checked the expression of Piezo2 in engineered heart tissue models with increased afterload. Immunhistochemical staining of Piezo2 was done for localization.

Results: We found a significant increase of Piezo2 expression in heart tissue of mice 2 weeks after TAC and 3 weeks after continuous angiotensin II infusion in comparison with the control groups. Also, in engineered heart tissue model of cardiac hypertrophy, we found a rise of Piezo2 expression. According to immunhistochemical staining, Piezo2 seems to be located in cardiomyocytes.

Conclusion: We found an increase of Piezo2 expression in heart tissue in different models of cardiac hypertrophy. Piezo2 seems to play a role in mechanosensation of the heart. Further work is needed to clarify the function of Piezo2 in the heart and its prospective effect on the development of heart failure.