Rotenone targeting the oxidative phosphorylation pathway improves invasive lesions in ovarian endometriosis

Abstract

Abstract Endometriosis (EM) is a prevalent gynecological disorder characterized by diagnostic difficulty and high recurrence rates. In this study, single-cell RNA sequencing (scRNA-seq) was performed to characterize endometrial stromal cell (ESC) subpopulations in EM, investigate the involvement of the oxidative phosphorylation (OXPHOS) pathway in EM pathogenesis and fibrosis, and assess the therapeutic effects of Rotenone, a mitochondrial electron transport chain complex I inhibitor. Twelve endometrial single-cell samples from the GSE179640 dataset were analyzed to compare cellular composition between EM and control groups, and to identify EM-associated pathways using Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The role of OXPHOS was further validated using clinical samples, in vitro assays, and in vivo animal models, with evaluation of histopathology, fibrosis, and mitochondrial function. scRNA-seq analysis demonstrated increased proportions of stromal, lymphoid, and myeloid cells in EM. Subcluster analysis of ESC subclusters revealed enrichment of the eStromal_cycling population, with differentially expressed genes significantly associated with the OXPHOS pathway. Ectopic EM lesions exhibited disrupted tissue architecture, increased collagen deposition, elevated mitochondrial complex I activity and adenosinetriphosphate (ATP) levels. OXPHOS-related proteins were co-localized with Vimentin in ectopic tissues. In vitro, Rotenone suppressed proliferation, migration, and invasion of ectopic endometrial stromal cells (ecESCs), and reduced complex I activity, ATP production, and OXPHOS protein expression. In vivo, Rotenone treatment reduced ovarian cystic lesions and adhesions, decreased fibrosis area, restored estradiol and progesterone levels, and reduced the co-localization of OXPHOS and stromal markers. These findings indicate that activation of the OXPHOS pathway in stromal cells is associated with disease progression and fibrosis. Inhibition of mitochondrial complex I attenuated lesion development and fibrosis in experimental models, suggesting that metabolic modulation may represent a potential therapeutic approach for EM.