Abstract

Background Endometriosis (EMs) is a prevalent gynecological disorder characterized by the ectopic growth of functional endometrial tissue, and its fibrotic pathology represents a primary contributor to chronic pain and infertility in affected patients. Hypoxia, a hallmark of the endometriotic microenvironment, is a well-established driver of fibrogenesis. However, the precise molecular mechanisms translating hypoxic signaling into pro-fibrotic responses remain elusive. The mechanosensitive ion channel Piezo1 is recognized as a contributor to fibrosis in various diseases; whereas its specific role in endometriosis is poorly understood. We demonstrate that hypoxia-inducible factor 1-alpha (HIF-1α) and Piezo1 are co-upregulated alongside fibrosis in EMs patient lesions. Functionally, both hypoxia and Piezo1 agonism promote fibrogenesis in HESCs. Mechanistically, hypoxia acts through Piezo1 to induce Ca²⁺-dependent mitochondrial damage and mitochondrial DNA (mtDNA) leakage, which in turn activates the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling and subsequently drives fibrosis. Therefore, we identifying the axis as a promising therapeutic target for future intervention. Methods This study combines clinical tissue analysis with in vitro cellular experiments. Normal endometrial tissue, eutopic and ectopic endometrial samples from patients with endometriosis were collected. Immunohistochemistry (IHC), immunofluorescence (IF), western blotting, and quantitative reverse transcription PCR (qRT-PCR) were used to analyse the expression levels of HIF-1α, Piezo1, cGAS, STING, and the fibrosis markers α-smooth muscle actin (α-SMA) and type I collagen (Collagen I). In vitro experiments, we utilized HESCs to establish a hypoxic culture model. IF, western blotting, and qRT-PCR were employed to assess the expression of HIF-1α, Piezo1, and fibrosis-related markers across experimental conditions. Combined flow cytometric analysis and EdU assays, 24 h