The m6A modification-mediated upregulation of ETS2 translation drives arsenic-induced spermatogonial senescence

Accumulating evidence indicates that arsenic (As) exposure causes a decline in sperm quality. This study aimed to investigate the impact of As exposure on spermatogonial senescence. GC-1 cells were exposed to NaAsO₂ (10 μM). RNA sequencing and ribosome profiling sequencing were performed to identify key regulators of cellular senescence. Methylated RNA immunoprecipitation-qPCR was used to determine N⁶-methyladenosine (m6A) modification. The results revealed that the differentially expressed genes were enriched in pathways related to cellular senescence. Several established senescence markers, β-galactosidase activity, γ-H2AX, and P16, were elevated in As-exposed GC-1 cells. Further analysis revealed that P21 and its transcription factor ETS2 were upregulated. ETS2 knockout prevented As-induced P21 upregulation and cell senescence. The multi-omics joint analysis indicated that As exposure elevated ETS2 translation efficiency by YTHDC2-dependent m6A modification. Mechanistically, As exposure induced mitochondrial dysfunction. Alpha-ketoglutarate (α-KG), a tricarboxylic acid cycle intermediate and RNA demethylase cofactor, was reduced in As-exposed GC-1 cells. Additional experiments showed that As exposure induced NAD⁺ depletion and suppressed SIRT3 activity. Supplementation with nicotinamide mononucleotide, an NAD⁺ precursor, attenuated As-evoked α-KG reduction and ETS2 upregulation. These findings suggest that As induces spermatogonial senescence via m6A modification-mediated upregulation of ETS2 translation and identify NAD⁺ replenishment as a potential countermeasure.