Conserved signaling pathways and transcriptional regulators drive ovarian aging across species.

The ovary plays a pivotal role in female fertility and endocrine homeostasis, and it is among the earliest organs to exhibit age-related dysfunction. However, the conserved molecular mechanisms underlying ovarian functional decline across species remain poorly understood. We integrated single-cell transcriptomic data from chicken, human, mouse, and yak ovaries to construct a cross-species ovarian single-cell atlas. Through cell-cell communication and transcription factor regulatory network analyses, we identified conserved signaling pathways (CXCL, VEGF, and VISFATIN) and conserved transcription factors (TFs), namely Klf6, Mef2a, Tead1, and Elk1. We further revealed that five upstream TFs (Rbpj, Myc, Sp1, Stat3, and Max) potentially regulate these conserved pathways. By analyzing multi-time-point single-cell data from mouse and human ovaries, we identified 30 key genes with consistent expression changes during ovarian functional decline. Notably, the time-varying TFs Stat3 and Max were shown to regulate the VEGF and VISFATIN pathways via Vegfa and Insr, respectively. Using DF-1 and NIH/3T3 senescence models, we found conserved stress-responsive expression patterns for Rbpj, Myc, Sp1, and Stat3, whereas Max showed differential responses between DF-1 and NIH/3T3 cells. Collectively, this cross-species single-cell transcriptomic study provides insights into conserved molecular mechanisms driving ovarian functional decline and offers potential therapeutic targets for ovary-related diseases.