Hijacked pathways: PFOS, the ATF2/WT1 axis, and the mitochondrial dysfunction in Sertoli cells.

Perfluorooctane sulfonate (PFOS), a persistent organic pollutant, is associated with male reproductive disorders, yet its mechanisms remain poorly understood. Using in vivo (ICR mice exposed to 0.5, 5, and 10 mg/kg/d PFOS for 28 days) and in vitro models, we investigated the role of the transcription factor 2 (ATF2) / Wilms' tumor 1 (WT1) axis in PFOS-induced Sertoli cells (SCs) injury. Firstly, male ICR mice were administered PFOS (0.5, 5, and 10 mg/kg/d) for 28 days. PFOS exposure caused decreased sperm counts, disrupted blood-testis barrier (BTB) integrity, and ultrastructural damage to the SC. Integrated transcriptomic-metabolomic analyses revealed mitochondrial metabolic reprogramming as a core alteration: Transcriptomics: 271 differentially expressed genes (DEGs) were identified, with significant downregulation of Wt1 (a master SC differentiation regulator) and Cyp21a1 (mitochondrial regulatory gene). Pathway enrichment confirmed dysregulation in oxidative phosphorylation, TNF signaling, and steroid hormone biosynthesis. Metabolomics: Accumulated TCA intermediates (succinate) and glycolytic metabolites (glucose, phosphoenolpyruvate) indicated energy metabolic reprogramming; elevated lipid peroxidation markers (13-HODE) confirmed oxidative stress. These changes aligned with WT1 suppression, mitochondrial impairment (swelling, cristae loss, reduced ATP), and SC vacuolization. Pathologically, PFOS elevated testicular transforming growth factor-β3 (TGF-β3), p-ATF2, and p-p38 while suppressing WT1, Connexin43, and Occludin-corroborated in vitro with concurrent mitochondrial ROS (mtROS) overproduction. Crucially, ATF2 knockdown or WT1 overexpression rescued BTB junction proteins, restored transepithelial electrical resistance (TEER) in primary SCs, and normalized mtROS. We conclude that PFOS hijacks the ATF2/WT1 axis to drive SC injury, converging on mitochondrial metabolic reprogramming and dysfunction as the central mechanism.