New dammarane triterpenoid saponins from the leaves of Cyclocarya paliurus
Abstract Three new dammarane triterpenoid saponins, cyclocariosides O-Q (1–3), were isolated from the ethanolic extracts of the leaves of Cyclocarya paliurus. The structures of these compounds were elucidated by spectroscopic methods.
Immunomodulatory effects of an acetylated Cyclocarya paliurus polysaccharide on murine macrophages RAW264.7.
Polysaccharides (CP) extracted from the leaves of Cyclocarya paliurus (C. paliurus) have been shown to possess a variety of biological activities. In present study, CP was successfully modified to obtain its acetylated derivative Ac-CP. Its potential immunomodulatory activities on RAW264.7 macrophages were investigated. Results showed that the acetylated polysaccharide Ac-CP could significantly stimulate macrophage proliferation, its actions were significantly stronger than that of the corresponding unmodified polysaccharide, CP. Meanwhile, the NO production activities of macrophages were not significantly enhanced by Ac-CP compared to CP group. In addition, both the phagocytic activity and levels of cytokines TNF-a, IL-1β and IL-6 were enhanced in the RAW264.7 macrophages by stimulation of Ac-CP. These results indicated that the acetylated derivative Ac-CP could enhance the activation of peritoneal macrophages, and acetylation modification can enhance the immunomodulation function of CP, indicating the potential application of acetylated polysaccharide as an immunotherapeutic adjuvant.
Antitumor and immunomodulatory activity of a water-soluble polysaccharide from Grifola frondosa.
Grifola frondosa has long been known and respected as a medically important fungus. This study investigated the characterization, antitumor and immunomodulatory activity of a polysaccharide named GP11 purified from G. frondosa. The results revealed that GP11 was composed of → 1)-D-Manp-(6 →,→ 1)-D-Glcp-(4 →,→ 1)-D-Galp-(6 → and → 2,3,6)-D-Glcp-(1 →, with branches attached at O-2,3 of 1,2,3,6-linked Glcp residues and terminal T-Glcp. GP11 exhibited indirect cytotoxic activity against HepG-2 cells in vitro, and it significantly inhibited the growth of Heps cells in vivo. GP11 increased the relative thymus and spleen weights as well as serum tumor necrosis factor-alpha and interleukin-2 levels. GP11 stimulated tumoricidal activity and the production of nitric oxide (NO), TNF-α and interleukin-1β, and it also stimulated the protein expression of iNOS and mRNA expression of iNOS and TNF-α. TLR-4 is a potential receptor for GP11-mediated macrophage activation. The results suggested that the antitumor activity of GP11 may be due to the improvement of immune functions through the TLR-4-mediated up-regulation of NO and TNF-α.