Evaluation of the new anti-inflammatory compound ethyl salicylate 2-O-β-D-glucoside and its possible mechanism of action.

Ethyl salicylate 2-O-β-d-glucoside (ESG) is a derivative of natural salicylate isolated from Gaultheria yunnanensis (Franch.) Rehder, it has been used for the treatments of rheumatoid arthritis, swelling and pain. The aim of this study was to evaluate the anti-inflammatory effects of ESG and explore the anti-inflammatory mechanisms. We found that ESG had potent anti-inflammatory effects on the lipopolysaccharide (LPS)-activated murine macrophages RAW264.7. ESG exerted a dose-dependent inhibition of the LPS-stimulated release of the pro-inflammatory cytokines TNF-α and IL-1β. Moreover, it significantly inhibited LPS-stimulated the production of NO and PGE2 by repressing the expression of iNOS and COX protein respectively. Western blot analysis showed that ESG prominently inhibited LPS-induced activation of NF-κB in RAW264.7 cells by blocking phosphorylation of inhibitor IκBα and p65. Consistent with these results, we found that ESG prevented the nuclear translocation of NF-κB induced by LPS. Our study suggests that ESG may be effective in the treatment of inflammatory diseases by inhibiting the pro-inflammatory cytokine production and regulating the NF-κB signal pathway.