In Vivo Assessment of the Testosterone-Induced PCOS Process on Adult Zebrafish Model with Spectral-Domain Optical Coherence Tomography

Polycystic ovary syndrome (PCOS) is a common endocrine disorder characterized by ovarian dysfunction and hyperandrogenism. Research into its dynamic pathological mechanisms is limited by the invasive nature of conventional histological methods, which preclude monitoring in live models. The zebrafish has emerged as a valuable model for PCOS due to its physiological similarities to humans. This study explores the application of spectral-domain optical coherence tomography (SD-OCT) as a high-resolution imaging tool for the assessment of PCOS progression and treatment in zebrafish. A testosterone-induced PCOS model was established in adult female zebrafish. The therapeutic efficacy of two doses of Metformin was evaluated. The core methodology involved in vivo SD-OCT imaging of ovarian follicles at multiple time points over 72h. These morphological changes observed via SD-OCT were consistently corroborated by histology. Metformin treatment, particularly at the high dose (100mg/L), demonstrated a pronounced therapeutic effect, effectively reversing the testosterone-induced follicular arrest and normalizing ovarian testosterone levels and gonadosomatic index (GSI). This study validates SD-OCT as a powerful and reliable modality for non-invasive monitoring of PCOS in a live zebrafish model.