Abstract
Cistus x incanus L. is a Mediterranean evergreen shrub used in folk medicine for the treatment of inflammatory disorders but the underlying mechanisms are not fully understood. We therefore investigated the anti-inflammatory effects of an ethyl acetate fraction (EAF) from C.x incanus L. leaves on lipopolysaccharide (LPS) activated RAW 264.7 macrophages. HPLC analysis revealed myricetin and quercetin derivatives to be the major compounds in EAF; EAF up to 1µM of total phenolic content, was not cytotoxic and inhibited the mRNA expression of interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) (p<0.05) and the production of prostaglandins E2 (PGE2) (p<0.05). Meanwhile, EAF triggered the mRNA expression of interleukin-10 (IL-10) and elicited the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2), as well as the expression of its main target gene, heme oxygenase-1 (HO-1) (p<0.05). These data indicate that EAF attenuates experimental inflammation via the inhibition of proinflammatory mediators and at least in part, by the activation of Nrf2/HO-1 pathway. These effects are likely due to myricetin and quercetin derivatives but the role of other, less abundant components cannot be excluded. Further studies to confirm the relevance of our findings in animal models and to highlight the relative contribution of each component to the anti-inflammatory activity of EAF should be conducted.
Highlights
Our results showed that ethyl acetate fraction (EAF) was rich in total phenolic content and that myricitrin and rutin were the most abundant compounds (Table 1)
Our results demonstrate that EAF inhibited the LPS-induced production of prostaglandins E2 (PGE2) by suppressing the transcription of COX-2
EAF reduced the mRNA expression of the proinflammatory cytokine IL-6 and elicited that of the anti-inflammatory cytokine IL-10. These beneficial effects were accompanied by the activation of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) that plays an important role in cellular defense against oxidative stress [24] and inflammation [18]
Summary
Cistus x incanus L. (Pink Rockrose, syn. C. creticus) is a hybrid between C. albidus and C. crispus, a species of shrubby plant of the Cistaceae family, commonly used in the Mediterranean folk medicine for its anti-inflammatory and skin protective properties [1,2,3,4]. M. D’Ambrosio et al.: Anti-inflammatory effects of C. incanus ethyl acetate extract results as anti-HIV agent [8] and in the treatment of infections of the upper respiratory tract [12]. D’Ambrosio et al.: Anti-inflammatory effects of C. incanus ethyl acetate extract results as anti-HIV agent [8] and in the treatment of infections of the upper respiratory tract [12] All these commercial products are especially promoted for their high polyphenolic content [13]. Numerous single phenolic compounds such as resveratrol, quercetin and myricetin derivatives have shown anti-inflammatory activities [17,18,19,20]. The flow rate was 0.6 mL/min and the injection volume was 10 μL
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
