Ferulic Acid Protects Against LPS-Induced Sheep Hepatocytes Oxidative Damage via Activating the GSH-GPX4 Pathway and Inhibiting Lipid Metabolism-Mediated Ferroptosis.

Lipopolysaccharide (LPS) triggers oxidative damage in sheep hepatocytes, linked to ferroptosis. Ferulic acid (FA) is known for its antioxidative properties, but its protective role against LPS via ferroptosis regulation was unclear. The objective of this research is to explore the protective role of FA in mitigating LPS-induced oxidative stress in sheep hepatocytes. The experimental setup consisted of three groups: a control group, an LPS group treated with 10 µg/mL of LPS, and FA group that received both 10 µg/mL of LPS and 750 µg/mL of FA. We found that FA treatment decreased in contents of MDA and LDH. Metabolomics revealed that LPS affected glycerophospholipid metabolism, unsaturated fatty acids biosynthesis, ferroptosis, and arachidonic acid metabolism mainly by reducing the level of PUFAs and LPC in the hepatocyte supernatant, while FA affected glutathione metabolism by increasing L-cysteine, L-ornithine, L-glutamic acid, and L-glutamine. Moreover, transcriptomics demonstrated that the comparison of LPS and control groups were mainly enriched in arachidonic acid metabolism, glycerophospholipid metabolism, and ferroptosis, the comparison of FA and LPS groups was mainly enriched in glutathione metabolism. The results further confirmed the findings in the metabolomics and transcriptomics analyses, showing that LPS treatment upregulated the mRNA expression of ACSL4, LPCAT3, ALOX15, STEAP3, GPX4, GCLC, and GCL in hepatocytes, while reducing GSH and GR levels. In contrast, FA intervention attenuated LPS-induced iron overload by decreasing Fe2+ accumulation and suppressing the mRNA expression of ACSL4, LPCAT3, STEAP3, and ALOX15. Furthermore, FA enhanced the expression of GPX4, GCLC, GCLM, and restored GSH content in LPS-exposed hepatocytes. The above results demonstrated that the protective effect of FA on LPS-induced oxidative damage in the sheep hepatocytes was achieved by activating the GSH-GPX4 pathway and inhibiting lipid metabolism-mediated ferroptosis.