Ameliorative effects of lycopodium clavatum in letrozole and high-fat diet induced PCOS-IR in rats: integrated evidence suggesting the involvement of PI3K/AKT-associated signalling

Background Polycystic ovary syndrome with insulin resistance (PCOS-IR) is a complex endocrine–metabolic disorder characterised by hyperandrogenism, ovulatory dysfunction, insulin resistance, and chronic low-grade inflammation, playing central pathogenic roles. In this context, Lycopodium clavatum was investigated based on the therapeutic relevance of Lycopodium-derived Traditional Chinese Medicine, Herba Lycopodii (Shenjincao, 伸筋草), whose phytoconstituents have been reported to exhibit anti-inflammatory, antioxidant, and metabolic regulatory properties. Objective This study investigated the therapeutic potential and mechanistic basis of Lycopodium clavatum mother tincture (Lyc-MT) and 6C potency (Lyc-6C) in a letrozole- and high-fat diet-induced PCOS-IR rat model using an integrated experimental and computational approach. Methods Phytochemical constituents were identified using LC–MS/MS, and network pharmacology was employed to predict bioactive compounds, targets, and pathways. Molecular docking was subsequently performed to evaluate the predicted interactions of selected compounds with core targets. PCOS-IR was induced in female Wistar rats using letrozole and a high-fat diet for 28 days, followed by treatment with metformin, Lyc-MT, and Lyc-6C for 30 days. Efficacy was assessed through metabolic, hormonal, oxidative stress, inflammatory, histopathological, and gene expression analyses. Results LC-MS/MS profiling identified 30 phytochemical constituents, while network pharmacology predicted 22 bioactive compounds potentially associated with multiple PCOS-IR-related targets and pathways, including the PI3K–AKT signalling pathway. Molecular docking further supported favourable interactions of selected Lyc compounds with core targets involved in insulin signalling and ovarian steroidogenesis. Compared with untreated PCOS-IR rats, treatment with Lyc-MT and Lyc-6C significantly improved metabolic and reproductive parameters, including reductions in body weight, ovarian weight, fasting glucose, insulin, HOMA-IR, luteinizing hormone, and testosterone levels, and restoration of follicle-stimulating hormone and oestradiol levels (p < 0.001). Estrous cyclicity was normalised in the treated groups. Oxidative stress-associated biomarkers showed significant improvement, with increased catalase, superoxide dismutase, and glutathione peroxidase activities and reduced malondialdehyde and TNF-α levels compared to the disease controls (p < 0.001). Furthermore, Lyc-MT and Lyc-6C significantly modulated the ovarian expression of INSR, PI3K, AKT, GLUT4, and CYP19A1, accompanied by improved ovarian histoarchitecture, including reduced cystic follicles and increased corpora lutea. Conclusion The findings suggest that Lyc-MT and Lyc-6C ameliorate metabolic, hormonal, oxidative stress-associated, inflammatory, and ovarian abnormalities in PCOS-IR rats, possibly by modulating the expression of PI3K/AKT signalling-related genes. In conclusion, Lyc-MT and Lyc-6C are promising multi-target adjunctive therapeutic candidates for PCOS-IR management.