RESUMEN
A polysaccharide termed Se-GP11 was extracted and purified from Se-enriched Grifola frondosa in our previous study. This study investigated the characterization, anti-tumor and immunomodulatory activity of Se-GP11. The results showed that Se-GP11 was composed of mannose, glucose and galactose with a molar ratio of 1:4.91:2.41. The weight-average molecular weight (Mw) and weight-average mean square radius (Rw) of Se-GP11 in 0.1M sodium chloride solution were 3.3×10(4)Da and 32.8 nm. Se-GP11 existed as a globular conformation with random coil structure. Se-GP11 had no anti-tumor activity against HepG-2 cells in vitro, and it significantly inhibited the growth of Heps tumor in vivo. Se-GP11 increased the relatively thymus and spleen weights as well as serum necrosis factor-alpha (TNF-α) and interleukin-2 (IL-2) levels. In addition, Se-GP11 promoted the phagocytosis and NO production of RAW264.7 as compared with that of the normal control group. The results revealed that the Se-GP11 may exhibit the anti-tumor through improving immunologic function of the tumor bearing mice.
Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Polisacáridos Fúngicos/química , Polisacáridos Fúngicos/farmacología , Grifola/química , Factores Inmunológicos/química , Factores Inmunológicos/farmacología , Selenio/química , Animales , Biomarcadores , Línea Celular Tumoral , Modelos Animales de Enfermedad , Femenino , Humanos , Activación de Macrófagos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
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 â 1)-D-Manp-(6 â,â 1)-D-Glcp-(4 â,â 1)-D-Galp-(6 â and â 2,3,6)-D-Glcp-(1 â, 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-1ß, 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.