Epigenomic determinants of ferroptosis via oxidative stress in IPEC-J2 cells exposed to Ochratoxin A

The intestinal epithelium serves as a frontline defense against dietary contaminants, such as Ochratoxin A (OTA), a mycotoxin linked to oxidative stress and cell death. OTA Toxicity is well documented; however, the epigenetic mechanisms driving its effects through chromatin remodeling and histone H3K27ac modifications remain poorly understood. We demonstrated that OTA-induced oxidative stress in porcine intestinal epithelial cells (IPEC-J2) promotes ferroptosis, a lipid peroxidation-driven cell death, through epigenomic dysregulation. Multi-omics profiling (RNA-seq, ATAC-seq, and H3K27ac CUT&Tag) showed extensive chromatin and transcriptional changes: 84,744 differentially accessible regions (51,653 open; 33,091 closed) mapping to 13,828 genes, and 19,075 dynamic H3K27ac cis-regulatory elements (8923 upregulated; 10,152 downregulated) linked to 5783 and 3198 genes, respectively. Integrative analysis identified 2622 genes with coordinated shifts in expression, accessibility, and histone marks; 822 were upregulated with enhanced promoter/enhancer activity, whereas 1800 were downregulated with epigenetic silencing. Ferroptosis-related pathways, including lipid peroxidation, iron metabolism, and PUFA metabolism, were enriched. OTA-treated cells exhibited increased levels of reactive oxygen species, lipid peroxides, and cell death (p ≤ 0.05). Cross-referencing FerrDb revealed 89 ferroptosis-associated genes, including upregulated effectors CYLD, PLA2G4α, ALOX15, and TP53, showed greater chromatin accessibility and active marks; antioxidant genes such as GCLC and SLC1A5 were repressed with chromatin closure, SCD shown same trend. Motif enrichment analysis implicated SP2, ATF3, CREB5, and ETV4 in initiating epigenetic reprogramming. Notably, ETV4 acts as a repressor of SLC39A13, disrupting metal homeostasis and promoting calcium-dependent lipid peroxidation via cPLA2-ALOX15. ETV4 knockdown increased SLC39A13 expression, reversing OTA-induced repression. These findings demonstrate that OTA triggers ferroptosis through epigenomic remodeling, linking chromatin state changes to disrupted metal homeostasis and calcium-dependent lipid peroxidation, and positioning ferroptosis as a therapeutic target against OTA-induced intestinal injury.