MetaboLightsapplication/xmlftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS13957/m_MTBLS13957_LC-MS_positive_hilic_metabolite_profiling_v2_maf.tsvftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS13957/a_MTBLS13957_LC-MS_positive_hilic_metabolite_profiling.txtftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS13957/s_MTBLS13957.txtftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS13957/i_Investigation.txtprimaryOK200ftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS13957<p>To determine uridine concentrations in mouse plasma and ovarian tissues, targeted metabolomic analysis was performed by BioProfile Technologies using LC-MS.&nbsp;</p>MetaboLightsPublicLiquid Chromatography MS - positive - hilic<p>All samples and standards were analyzed using a QTRAP 5500 mass spectrometer (AB SCIEX) operated in positive ion mode.</p>Uridine restores oocyte quality and mitigates female reproductive aging by inhibition of ferroptosis in mice.Jianing Shenjingyue chenPeking University Third Hospitalovaryblood plasmamixturepure substancemass spectrometry assay<p>Absolute quantification of uridine was achieved using an isotope-labeled internal standard (HY-B1449S10, MedChemExpress). Plasma and ovarian samples were deproteinized by organic solvent precipitation and subjected to reversed-phase chromatographic separation. Uridine standards (U3003, Sigma-Aldrich) were dissolved in 50% methanol/water and serially diluted to generate a calibration curve.</p>Mus musculusreference compoundhttps://www.ebi.ac.uk/metabolights/MTBLS13957Jingyue Chen. 3222313849@qq.com.Guangjun Huang.Dongxu Li.Liying Yan.Rui Wang.Jie Qiao. State Key Laboratory of Female Fertility Promotion, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China.. jie.qiao@263.net.Xiaofan Sun.Peng Yuan.Meijie Chen.Bo Xiong.Jianing Shen. cmshenjianing@163.com.Tianyi Liao.<p>Data acquisition and quantification were performed using MultiQuant Software (v3.0.31721.0).</p>Groupcmshenjianing@163.com3222313849@qq.com<p>Female C57BL/6J mice were assigned to three groups: young (6-8 weeks), aged (48-56 weeks), and aged mice supplemented with uridine (48-56 weeks). Uridine concentrations were quantified in plasma (young: n = 13; aged: n = 13; uridine + aged: n = 12, biologically independent mice) and ovarian tissues (young: n = 14; aged: n = 16; uridine + aged: n = 15, biologically independent mice). For each mouse, whole blood was collected into 1.5 mL sodium heparin-coated tubes, gently inverted to mix, and left at 4 °C for 1 hour. Samples were then centrifuged at 1150 × g for 10 minutes at 4 °C. The upper plasma layer was carefully transferred to clean tubes, snap-frozen in liquid nitrogen for 5 minutes, and stored at -80 °C until analysis. Bilateral ovaries were also collected from each mouse, rinsed briefly in ice-cold PBS to remove residual blood and debris, snap-frozen in liquid nitrogen for 5 minutes, and stored at -80 °C prior to analysis.</p>MetabolomicsOvaryoocyte quality, abnormalferroptosisAgingliquid chromatography-tandem mass spectrometryUridineAdvanced Maternal Agetargeted metabolite profilingOvaryoocyte quality, abnormalferroptosisAgingliquid chromatography-tandem mass spectrometryUridineAdvanced Maternal Agetargeted metabolite profiling<p>All samples and standards were analyzed using a QTRAP 5500 mass spectrometer (AB SCIEX) operated in positive ion mode.</p>falseUridine restores oocyte quality and mitigates female reproductive aging by inhibition of ferroptosis in mice<p>Advanced maternal age is a key factor in female infertility, primarily due to declines in ovarian reserve and oocyte quality. However, the metabolic mechanisms underlying reproductive aging are still poorly understood. Here, we show that uridine levels in the plasma and ovaries of aged mice are significantly reduced compared with young controls. Building on this, we find that uridine supplementation significantly improves meiotic maturation, fertilization, and early embryonic development of aged oocytes, both in vivo and in vitro. Further microtranscriptomic analyses reveal that uridine enhances oocyte quality by inhibiting ferroptosis, enhancing mitochondrial function and removing excessive reactive oxygen species (ROS). Moreover, integrating Limited Proteolysis-Small Molecule Mapping (LiP-SMap), surface plasmon resonance (SPR) analyses and siRNA-based functional assays, we identify that uridine binds Poly(rC)-binding protein 1 (PCBP1), thereby suppressing ferroptosis and preserving mitochondrial function. In conclusion, this study demonstrates that uridine supplementation can effectively improve fertility of aged female mice. Our research also provides important insights into the role of ferroptosis in oocyte aging, thereby advancing our understanding of reproductive aging mechanisms.</p>2026-03-032026-03-02MTBLS13957