Polycystic ovary syndrome (PCOS), a prevalent reproductive and endocrine disorder affecting 11–13 % of women globally, is diagnosed by the Rotterdam criteria (requiring at least two of the following: hyperandrogenism, ovulatory dysfunction, or polycystic ovaries) (Huddleston and Dokras, 2022). Hyperandrogenism contributes to both reproductive and metabolic disturbances in PCOS and can promote insulin resistance, together driving disease progression (Sanchez-Garrido and Tena-Sempere, 2020). Obesity, insulin resistance, hyperandrogenism, and chronic inflammation exacerbate metabolic dysfunction in PCOS, including hepatic disorders such as non-alcoholic fatty liver disease (NAFLD) (Xu et al., 2024). Reproductive outcomes include menstrual irregularity, infertility, endometrial dysfunction, and increased cancer risk (Wen et al., 2024). While insulin resistance, hyperandrogenism, and inflammation are recognized as core pathophysiological components, their downstream cellular mechanisms remain poorly defined. Therefore, elucidating the mechanisms that directly cause tissue dysfunction is crucial for developing novel disease-modifying therapies.

Current PCOS management relies on lifestyle modifications and pharmacotherapy such as oral contraceptives, anti-androgens, insulin sensitizers, and ovulation inducers. However, these approaches offer limited efficacy, do not target underlying causes, and frequently cause adverse effects (Teede et al., 2023), thus highlighting the need for safer, more comprehensive therapeutic alternatives. Traditional Chinese medicine (TCM) has emerged as a promising multi-target approach for PCOS. Yangjing Zhongyu decoction (YZD), a classical gynecological formula from Fu Qingzhu Nvke (A book published in the Qing Dynasty), containing Rehmannia glutinosa (Gaertn.) Libosch. ex DC., Paeonia lactiflora Pall., Angelica sinensis (Oliv.) Diels, and Cornus officinalis Siebold & Zucc., is a natural herbal medicine that has shown particular promise in the treatment of infertility. Clinical studies indicate that YZD effectively regulates hormone levels in infertile patients, promotes ovulation, and enhances endometrial receptivity, thereby improving pregnancy outcomes (Ma et al., 2022; Wu and Zhou, 2002, 2004; Zhao and Zhang, 2014). YZD shows significant efficacy in treating PCOS-related infertility, and it corrects hypothalamic-pituitary-adrenal axis dysfunction, improves sex hormone profiles and ovarian hemodynamics, and increases ovulation rates. Moreover, YZD promotes endometrial differentiation, increases endometrial thickness, and enhances endometrial receptivity, collectively improving clinical pregnancy outcomes in PCOS patients (Bai et al., 2022; Luo et al., 2019; Zhang et al., 2021; Zhang, 2020). In vitro studies show that YZD protects ovarian granulosa cells and improves follicular development by enhancing mitochondrial function, promoting estradiol synthesis, and regulating energy metabolism (Liu et al., 2022b; Zheng et al., 2014). In vivo studies indicate that YZD restores sex hormone balance and ovarian function in PCOS rats by modulating mitochondrial biogenesis and metabolic pathways (Nie et al., 2024). Additionally, YZD may alleviate the thin endometrium and restore uterine function in PCOS-like rats by promoting angiogenesis and endometrial repair through modulation of the phosphoinositide 3-kinase/protein kinase B signaling pathway, suggesting a potential mechanism for PCOS treatment (Zhang et al., 2023). However, the therapeutic mechanisms of YZD in PCOS treatment remain to be fully elucidated.

Ferroptosis, an iron-dependent form of regulated cell death driven by lipid peroxidation, may contribute to PCOS pathogenesis. Multi-omics studies indicate that glutathione metabolism disruption and ferroptosis overactivation, resulting from glutathione peroxidase 4 (GPX4) deficiency in endometrial epithelial cells, are direct consequences of the prolonged proliferative phase in PCOS endometrium (Ye et al., 2025). Concurrently, the analysis of several Gene Expression Omnibus datasets indicates the differential expression of ferroptosis-related genes in PCOS (Lin et al., 2023). Recent evidence suggests that iron metabolism dysregulation and ferroptosis can impair granulosa cell function, disrupt follicular development, and compromise uterine receptivity, all of which contribute to implantation failure and early pregnancy loss (Hu et al., 2025). Tissue-specific ferroptosis has been identified in PCOS patients and animal models, affecting the liver, ovarian granulosa cells, and endometrium (Zheng et al., 2023; Zhang et al., 2022; Zheng et al., 2023). These ferroptosis events correlate with PCOS features, including hyperandrogenemia, metabolic disturbances (e.g., hepatic steatosis and insulin resistance), and reproductive abnormalities (e.g., anovulation and endometrial dysfunction) (Zheng et al., 2023; Li et al., 2024; Peng et al., 2023; Zhang et al., 2020; Zheng et al., 2023). Ferroptosis further promotes inflammation through oxidized arachidonic acid-mediated lipoxygenase activation and immunogenic damage-associated molecular patterns (Sun et al., 2020), thus exacerbating PCOS pathologies such as hormonal disruption and ovarian dysfunction (Eltokhy et al., 2025). Ferroptosis thus acts as a proximal mediator translating insulin resistance, metabolic dysregulation, and inflammation into tissue damage in PCOS. Inhibiting ferroptosis might therefore offer a promising therapeutic strategy, potentially overcoming the limitations of current symptomatic treatments like insulin sensitizers and anti-androgens by addressing the core mechanism of cellular injury.

Network pharmacology and molecular docking analyses have shown that the pathways enriched for YZD in PCOS involve the ferroptosis-related PPAR signaling pathway (Yu et al., 2022). Furthermore, the herbal constituents of YZD have demonstrated ferroptosis-modulating activities. For example, Rehmannioside A from Rehmannia glutinosa (Gaertn.) Libosch. ex DC. alleviates ferroptosis-mediated cognitive impairment in cerebral ischemia by regulating the Solute Carrier Family 7 Member 11 (SLC7A11)/GPX4 axis (Fu et al., 2022). Paeoniflorin from Paeonia lactiflora Pall. enhances GPX4 activity and reduces malondialdehyde (MDA) accumulation, thereby improving neurological outcomes (Zhi et al., 2024). Angelica sinensis polysaccharide from Angelica sinensis (Oliv.) Diels suppresses GPX4 expression and reverses cisplatin resistance in ovarian cancer cells (Guo, W. et al., 2024), while morroniside from Cornus officinalis Siebold & Zucc. reduces iron levels and upregulates GPX4, thus protecting dopaminergic neurons in models of Parkinson's disease (Li et al., 2023). Collectively, these findings suggest that the TCM formula YZD and its component herbs exhibit ferroptosis-modulating properties. Nonetheless, the precise molecular mechanisms through which this regulation ameliorates the pathological features of PCOS require further in-depth investigation. Building upon this foundation, we hypothesized that YZD also ameliorates reproductive and metabolic dysfunction in PCOS by targeting the ferroptosis pathway. This study utilized a dihydrotestosterone (DHT)-induced hyperandrogenism mouse model, which also exhibits insulin resistance, as a classic model to mimic PCOS pathological features and to investigate its underlying mechanisms (Rodriguez Paris et al., 2021). Our study demonstrates that YZD improves PCOS-related metabolic and reproductive dysfunction through tissue-specific bidirectional regulation of ferroptosis markers in hepatic, ovarian, and uterine tissues.