Sesquiterpene lactones as inhibitors of IL-8 expression in HeLa cells

Twenty-four structurally different SLs were studied for their inhibition on IL-8 production in HeLa229 cells and different IC50-values were obtained. QSAR analyses revealed that the α-methylene-γ-lactone and the presence and reactivity of a second reaction center, expressed by LUMO2, are the most important descriptors for IL-8. Using two SLs as examples, we demonstrated that SLs prevent DNA binding of AP-1, which has binding sites in the IL-8 promoter together with NF-κB and C/EBP, and that this is probably due to directly targeting AP-1. p38 MAPK, which plays a role in AP-1 activation as well as in IL-8 regulation, was not influenced by SLs. These data show that NF-κB and AP-1, and consequently IL-8 may be interesting targets in antiinflammation research and that the small molecules of SLs may be powerful candidates with promising properties for therapeutic modulation of the inflammatory response.

Twenty-four structurally different sesquiterpene lactones were investigated for their inhibitory activity on IL-8 expression and a QSAR study was carried out. Using IC50 values from ELISA experiments an improved correlation factor (R = 0.821) was obtained compared to IC100 from the NF-κB EMSA (R = 0.709). Inhibition of NF-κB as well as AP-1 DNA binding may be involved in downregulation of IL-8 expression.Figure optionsDownload as PowerPoint slide