Anti-inflammatory and immune-modulatory properties of anemoside B4 isolated from Pulsatilla chinensis in vivo

Background: Pulsatilla chinensis is commonly used for the treatment of cancers and inflammatory disorders in China. Our recent studies showed that anemoside B4, its major ingredient, possessed notable antioxidant and protected cisplatin-induced acute kidney injury in vivo. Furthermore, we found the protective effect might be involved its anti-inflammation activities. However, its anti-inflammatory mechanisms are not clear. Purpose: In the present study, we extensively investigated the anti-inflammatory and immune-modulatory properties of anemoside B4 in vivo. Methods: To carry out this work, the xylene-induced ear edema and LPS-induced systemic inflammation of mice model was also used to evaluate the anti-inflammatory activity. Then, anti-inflammatory mechanism of anemoside B4 was further determined by pro-inflammatory cytokines production using enzyme-linked immunosorbent assay (ELISA) and nuclear factor-kappa-gene binding (NF-kappa B) pathway activation by Western blot. At last, immuno-modulatory effects were observed by splenocyte proliferation assay, delayed type hypersensitivity assay (DTH) and T cell subtype assay in mice. Results: 12.5-50 mg/kg anemoside B4 significantly suppressed xylene-induced mice ear edema. Furthermore, it ameliorated LPS-induced kidney and lung inflammation damage, which inhibited pro-inflammatory response by NF-kappa B pathway in mice. In addition, anemoside B4 decreased CD4(+)/CD8(+) ratio, inhibited splenic lymphocyte proliferation and decreased DNFB-induced changes of ear thickness. Conclusion: From these data, it can be concluded that anemoside B4 presented anti-inflammatory and immune-modulatory activities in vivo, and potentially be a novel natural anti-inflammatory drug candidate for treating inflammatory disorder.