Protective Effects of Tea Tree Oil on Inflammatory Injury of Porcine Intestinal Epithelial Cells Induced by Lipopolysaccharide In Vitro

作者：Li Dong, Qingqing Yuan, Guangzhi Qiu, Yong-Sheng Zhang, Hongrong Wang, Lihuai Yu · 发表于：Animals · 年份：2024 · DOI：10.3390/ani14172577 · 被引用次数：5 · 研究领域：Immune Response and Inflammation、Ginger and Zingiberaceae research、Essential Oils and Antimicrobial Activity

Tea tree oil (TTO) improves the intestinal mucosal immunity of weaning piglets, but its underlying mechanism is not clear. We hypothesized that TTO may alleviate inflammatory injury by regulating the function of intestinal epithelial cells. Ileum epithelial cells (IPI-2I) were chosen and an inflammatory injury cell model was generated. The cell viability, cytokine secretion, and gene expression of TLR4 and NF-κB were measured to further evaluate the effects of TTO on the inflammatory injury in immune-stressed cells. The results showed that lipopolysaccharide (LPS; content: ≥30 μg/mL; time: 3 h, 6 h, or 9 h) decreased cell viability (p < 0.01), and 50 μg/mL LPS stimulated for 6 h resulted in an increased secretion of proinflammatory cytokines and a dramatically decreased secretion of anti-inflammatory cytokines (p < 0.05) in IPI-2I cells. Concentrations of 0–0.05% of TTO improved cell viability, while the 0.03% TTO treatment resulted in the highest cell viability and alleviated LPS-induced cell death (p < 0.01). In addition, 0.03% TTO alleviated the LPS-induced increase in the gene expression of IL-1β, TNFα, and IFNγ, as well as the decrease in the expression of IL-10 in IPI-2I cells (p < 0.05). LPS also upregulated the gene expression of TLR4 and NF-κB (p < 0.05); while TTO supplementation alleviated this effect (p < 0.05), 0.03% and 0.05% TTO supplementation had greater effects (p < 0.05). In conclusion, 50 μg/mL LPS stimulated for 6 h can be used to est...