Anti-inflammatory effects of immature Citrus unshiu fruit extracts via suppression of NF-kappa B and MAPK signal pathways in LPS-induced RAW264.7 macrophage cells

=This study examined the anti-inflammatory effects of 70% ethanol crude extract of immature Citrus unshiu fruits (ICE) and its solvent fractions in LPS-stimulated RAW 264.7 cells. In addition, we analyzed the active compounds related to suppression of inflammation. It was found that the ethyl acetate (EtOAc) fraction showed the highest level of inhibition of NO production, and this inhibitory activity was concentration-dependent. Moreover, the EtOAc fraction not only inhibited TNF-alpha and IL-6 production but also inhibited iNOS and COX-2 protein expression. Furthermore, inhibition of NF-kappa B activity and MAPK phosphorylation was also observed. In addition, beta-sitosterol, campesterol and isoferulic acid were identified as major anti-inflammatory components in the EtOAc fraction. These results suggested that the EtOAc fraction of immature C. unshiu fruit extract exerts anti-inflammatory effects by inhibiting NF-kappa B and MAPK signaling pathways, and that this fruit could be used as a natural anti-inflammatory material.

Automated summary

This study investigated the anti-inflammatory effects of immature Citrus unshiu fruit extract, finding that the ethyl acetate fraction showed the highest inhibition of NO production and pro-inflammatory cytokine production. Additionally, it inhibited the expression of inflammation-related proteins and the activity of NF-kappa B and MAPK signaling pathways. Furthermore, three major anti-inflammatory components, beta-sitosterol, campesterol, and isoferulic acid, were identified in the ethyl acetate fraction.