The Metabolic Homeostasis of Harpagoside and Taurine Sustains Postovulatory Oocyte Quality.

Balanced metabolic homeostasis is critical for maintaining high-quality oocytes. Growing evidence suggests that metabolic dysregulation induced by postovulatory aging severely compromises oocyte quality. However, the metabolic signatures of postovulatory aged oocyte remain poorly characterized. In this study, we employed metabolomic sequencing to delineate the distinctive metabolic alterations in postovulatory aged (PostOA) oocytes. Notably, we identified that Harpagoside accumulation in PostOA oocytes leads to reduced nitric oxide (NO) levels, resulting in spindle/chromosome instability and DNA damage. Furthermore, we demonstrated that Taurine plays a crucial role in preserving the quality of PostOA oocytes. Exogenous Taurine supplementation significantly rescued meiotic defects in PostOA oocytes, primarily by restoring mitochondrial function and enhancing developmental competence. Collectively, our findings provide a valuable resource for understanding metabolic remodeling during postovulatory aging and highlight potential therapeutic strategies to mitigate aging-related oocyte deterioration.