Xanthatin alleviates LPS-induced inflammatory response in RAW2647 macrophages by inhibiting toll-like receptor 4 pathway
Xanthatin (XT) is a sesquiterpene lactone isolated from the Chinese herb Xanthium, which belongs to the Asteraceae family. Here, we developed an in-flammation model via stimulating RAW 264.7 cells with LPS, which was applied to assess the anti-inflammatory effect and probable mechanisms of xanthatin. Pretreatment with of xanthatin lowered the amount of NO and associated pro-inflammatory factors (TNF-α, IL-1β and IL-6), which were enhanced in the cells after LPS-activated. Interestingly, RAW 264.7 cells were pre-treated with xanthatin, the mRNA expression of iNOS, COX-2, TNF-α, IL-1β and IL-6 was downregulated and repressed as compared with the only LPS-induced group. Furthermore, phosphorylated levels of related proteins (STAT3, ERK1/2, SAPK/JNK, IκBα, p65) were notably increased with the only LPS-activated cells. Interestingly, these phosphorylated proteins could be reverted by pre-treating with xanthatin in a dose-dependent way. Additionally, xanthatin was involved to block NF-κB p65 from translocating into the nucleus and activating inflamma-tory gene transcription. Collectively, these results demonstrated that xanthatin suppresseeds the inflammatory effect caused by LPS through downregulating NF-κB, MAPK and STATs signaling pathways. Taken together, xanthatin pos-sesses the potential to act as a good anti-inflammatory medication candidate.