Immunohistochemical Detection of the Mechano-Gated Piezo Channels in the Normal Endometrium and in Endometriosis

Endometriosis is an inflammatory estrogen-dependent disorder characterized by pain, dyspareunia, dysmenorrhea, and infertility. This is due to the invasion of different organs by endometrial tissue that cause inflammation, angiogenesis, and fibrosis. The ion channels Piezo1 and Piezo2 primary work as mechanosensors and mechanotransducers but also have functions that could participate in the clinical hallmarks of the endometriosis. Thus, we investigated the occurrence and localization of Piezo1 y Piezo2 in the healthy human endometrium and in endometriosis using immunohistochemistry. In healthy endometrium Piezo1 immunoreactivity was detected in the glands and to a lesser extent in the stroma; Piezo2 was present in the same locations but at low or residual levels. In ectopic endometriosis, there was an increase in the intensity of Piezo1 regardless of their location; Piezo2 only showed a net increase in the ovary and vagina endometriosis foci. Present results demonstrate for the first time the occurrence of Piezo ion channels in the healthy human endometrium, as well as an increase in Piezo1 in ectopic endometriosis, and no changes in Piezo2 with the exception of the ovary and vagina. The role of these ion channels in the endometrium and in the pathogenesis of the endometriosis remains to be elucidated.