n-butanol extract from Folium isatidis inhibits the lipopolysaccharide-induced downregulation of CXCR1 and CXCR2 on human neutrophils

Wu, Beibei; Wang, Liyin; Jiang, Lili; Dong, Lili; Xu, Fengli; Lu, Yili; Jin, Jiahui; Wang, Zhanyue; Liang, Guang; Shan, Xiaoou

To date, the treatment of sepsis consists primarily of supportive measures and experimental therapeutic approaches (29) . Therefore, novel pharmacological strategies are urgently required to promote the treatment of sepsis (30) . With the ability to promote the expression of CXCR1, CXCR2 Figure 2 . n-butanol extract from Folium isatidis inhibits the downregulated protein levels of CXCR1, CXCR2 and CD62L. Following pretreatment with a vehicle control (DMSO) or n-butanol extract at the indicated concentration for 2 h, neutrophils were incubated with LPS (0.5 µg/ml) for 4 h. Expression levels of (A) CXCR1, (B) CXCR2 and (C) CD62L were measured using flow cytometry. The corresponding mean fluorescence intensity was calculated. Each bar represents the mean ± standard error of the mean of three independent experiments. Statistical significance relative to the LPS group was determined. ** P<0.01. LPS, lipopolysaccharide; CXCR1, CXC-chemokine receptor 1; CXCR2, CXC-chemokine receptor 2; CD62L, L-selectin. and CD62L, n-butanol extract itself is a potential candidate for the treatment of LPS-induced sepsis. However, due to the presence of multiple bioactive components in the extract and limited approaches for preparing extracts from F. isatidis, it is difficult to identify the precise agent inhibiting LPS-induced chemokine receptor downregulation. Although the main active chemical components have been identified, there are more than eight major compounds in n-butanol extract (22) . Further investigation is required to identify the active compound in F. isatidis.