Single-cell RNA sequencing across diverse cell types to identify PFOA-induced ovarian cellular senescence.

Perfluorooctanoic acid (PFOA) is a persistent environmental pollutant that has been associated with reproductive dysfunction, yet cellular mechanism underlying its ovarian toxicity remain poorly understood. From the perspective of cellular senescence, we conducted this study by establishing a murine (female ICR mice) PFOA exposure (10 mg/kg/day administered orally via gavage for 28 consecutive days), then examined changes in ovarian structure, cellular composition, and transcriptional profiles. Compared with the control group, we found significant reductions in follicle numbers across all developmental stages following PFOA exposure. To understand mechanisms underlying PFOA induced ovarian dysfunction, we performed single-cell RNA ovarian tissues and obtained 29,000 + cells with 8 distinct cell populations, where cumulus cells showed particular vulnerability to PFOA-induced depletion. Cell cycle analysis demonstrated widespread G1 phase accumulation, most prominently in granulosa and cumulus cells. Differential gene expression analysis revealed cell type-specific upregulation of senescence markers such as Cdkn1a, Smoc2, and Igfbp4 in follicular somatic cells. Integration of transcriptional profiling with cell cycle analysis established a mechanistic link between PFOA exposure, cell cycle arrest, and premature cellular senescence, which directly corresponded to the observed follicular depletion and structural abnormalities in histological analysis. In conclusion, PFOA exposure triggers ovarian pathology partially through induction of cell type-specific senescence programs that disrupt normal follicular development and function, which highlights cellular senescence as a potential contributor to environmental pollutant-mediated reproductive dysfunction.