Cell-resolved genetic risk reveals hyperandrogenism-associated immune and metabolic rewiring in the PMOS follicular microenvironment

Polyendocrine metabolic ovarian syndrome (PMOS) is a leading cause of anovulatory infertility. Although follicular developmental arrest is a defining feature of PMOS, the cell-type-specific mechanisms linking genetic susceptibility, endocrine imbalance and follicular microenvironmental dysfunction remain incompletely understood, particularly across clinical subtypes. We performed single-cell RNA sequencing of preovulatory follicular-fluid cells from healthy controls and women with uncomplicated PMOS, hyperandrogenic PMOS and metformin-treated insulin-resistant PMOS. We integrated these data with GWAS-derived disease relevance scores and ovarian chromatin-accessibility annotations to map genetic risk to follicular cell populations and regulatory programmes. Ligand–receptor analyses were used to infer intercellular communication networks. Transcriptomic metabolic findings were further assessed by follicular-fluid metabolic and steroid-hormone measurements, DHT-treated granulosa-cell functional assays, and reanalysis of a DHEA-induced mouse PMOS-like ovarian dataset. We generated a single-cell atlas of the PMOS follicular microenvironment comprising 220,983 high-quality cells. Granulosa cells showed the strongest enrichment of PMOS-related genetic risk, with regulatory-genetic support from ovarian snATAC-seq integration. Among granulosa cell states, a GC2_CYP19A1⁺ population was preferentially associated with hyperandrogenic PMOS and displayed a transcriptional programme characterized by steroidogenic remodelling coupled to reduced energy-metabolic activity. Biochemical profiling supported this endocrine–metabolic imbalance, showing increased follicular-fluid androstenedione (ASD) and estrone, reduced estradiol and E2/ASD ratio, decreased ATP, citrate and fumarate hydratase activity, and increased lactate and β-hydroxybutyrate. Prolonged DHT exposure impaired granulosa-cell mitochondrial respiration, ATP production and mitochondrial membrane potential. In parallel, PMOS subtypes showed immune remodelling and altered ligand–receptor signalling, with hyperandrogenic PMOS associated with increased inflammatory signalling and reduced homeostatic or tissue-repair pathways. Reanalysis of a DHEA-induced mouse ovarian dataset provided supportive evidence for androgen-associated steroidogenic pathway perturbation. This study provides a cell-resolved framework linking PMOS genetic susceptibility to endocrine–metabolic and immune remodelling in the preovulatory follicular microenvironment. The identification of a hyperandrogen-associated GC2_CYP19A1⁺ state highlights a candidate cellular programme in which steroidogenic imbalance is coupled to impaired granulosa-cell bioenergetics. These findings provide a resource for future validation and may inform microenvironment-guided stratification of PMOS and the development of strategies aimed at restoring follicular function.