Naringenin Inhibits Enterotoxigenic Escherichia coli-Induced Ferroptosis via Targeting HSP90 in IPEC-J2 Cells

Enterotoxigenic Escherichia coli (ETEC) leads to severe diarrhea in piglets. Naringenin (Nar), a natural flavonoid compound, is known for its antibacterial and anti-antioxidant properties. However, the protective effects of Nar against ETEC-induced diarrhea have not been reported yet. This study investigated the protective mechanisms of Nar against ETEC infection in porcine intestinal epithelial cells (IPEC-J2). ETEC infection induced oxidative stress and ferroptosis in IPEC-J2 cells by elevating intracellular iron content and ROS accumulation, increasing MDA levels, downregulating SOD activity and GPX4 expression, and upregulating the transcription of CHAC1 and SLC7A11. In contrast, Nar suppressed ETEC-induced ferroptosis of IPEC-J2 cells by inhibiting the SLC7A11/GPX4 pathway. Specifically, Nar mitigated mitochondrial damage, reduced intracellular iron levels and ROS accumulation, and ultimately reversed the oxidative stress. Network pharmacology and molecular docking identified heat-shock protein 90 (HSP90) as a potential target of Nar. Overexpression and knockdown experiments revealed that ETEC-induced ferroptosis was mediated by upregulation of HSP90, while the protective effects of Nar against ETEC-induced ferroptosis were dependent on the downregulation of HSP90. In conclusion, Nar targets host HSP90 to protect IPEC-J2 cells from ferroptosis caused by ETEC infection. This study demonstrates that Nar is a potent antioxidant natural compound with potential for preventing ETEC-induced intestinal damage.