Metabolic profiling of a polycystic ovary syndrome-like organoid model reveals the critical role of glutamine in local endometrial dysregulation related to implantation failure.

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder characterized by reproductive and metabolic disturbances, which causes a chronic lack of ovulation that leads to increased incidence of atypical endometrial hyperplasia and carcinogenesis. Increasing evidence indicates that metabolic changes may play a crucial role in PCOS pathogenesis; however, the metabolic profile of fluid in PCOS-related endometrium has not yet been characterized. In this study, we successfully constructed three cases of endometrial organoids derived from clinically healthy endometrium. We established a high-androgen model by adding different ratios of estradiol and testosterone to simulate PCOS-like characteristics. Through scanning electron microscopy and immunofluorescence detection, we found that extra androgen treatment-induced cellular damage led to cellular fragments and apoptosis. The intra-organoid fluid (IOF) and extra-organoid fluid (EOF) of the organoids were separated and analyzed by high-throughput quantitative metabolomics. The results showed that amino acid metabolism, specifically glutamine metabolic changes, was the major metabolic pathway altered in the EOF; meanwhile, changes in fatty acids were the main metabolites in the IOF among the groups. Specifically, the in vitro model confirmed that glutamine enhances endometrial stromal cell decidualization with altered mitochondrial function during the implantation process, which may provide the basis for metabolic marker screening and for identifying potential metabolic targets for intervention in female infertility related to PCOS.