Eleutherococcus senticosus extract attenuates LPS-induced iNOS expression through the inhibition of Akt and JNK pathways in murine macrophage

Eleutherococcus senticosus (Araliaceae) is immunological modulator which has been successfully used for anti-inflammatory effectors on anti-rheumatic diseases in oriental medicine. Mitogen-activated protein kinases (MAPKs) and Akt modulate the transcription of many genes involved in the inflammatory process. In this study, we investigated the inhibitory effects of Eleutherococcus senticosus on the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharides (LPS)-activated macrophages. Finally, we studied the involvement of MAPKs and Akt signaling in the protective effect of Eleutherococcus senticosus in LPS-activated macrophages. Eleutherococcus senticosus significantly attenuated LPS-induced iNOS expression but not COX-2 expression. In using the standard inhibitors (MAPKs and Akt), our results show that Eleutherococcus senticosus downregulates inflammatory iNOS expression by blocking JNK and Akt activation.