title: Immunomodulatory effect of Ganoderma atrum polysaccharide on CT26 tumor-bearing mice.
abstract: Ganoderma atrum has attracted great attention for its antitumor activity. However, the mechanism remains unclear. A G. atrum polysaccharide (PSG-1) showed pronounced antitumor activity in this study. PSG-1 did not kill CT26 cells directly, but inhibited the proliferation of CT26 cells via the activation of peritoneal macrophages (MΦ). In vivo, PSG-1 significantly suppressed the tumor growth in CT26 tumor-bearing mice. The treatment caused a significant increase in the immune organ index and the phagocytosis of macrophages. The production of TNF-α, IL-1β and nitric oxide also increased. Furthermore, we found that PSG-1 acted on Toll-like receptor (TLR) 4, signaled through p38 MAPK pathway, then activated NF-κB and stimulated TNF-α production. We further found that PSG-1 increased the expression of TLR4 and NF-κB, the degradation of IκBα and the phosphorylation of p38 MAPK. In summary, we have demonstrated that PSG-1 could activate macrophages via TLR4-dependent signaling pathways, improve immunity and inhibit tumor growth.
authors.affiliation: Department of State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, Jiangxi 330047, China.
authors.forename: Shenshen
authors.initials: S
authors.lastname: Zhang
authors.forename: Shaoping
authors.initials: S
authors.lastname: Nie
authors.forename: Danfei
authors.initials: D
authors.lastname: Huang
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Li
authors.forename: Mingyong
authors.initials: M
authors.lastname: Xie
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D016207:Cytokines / Q000235:genetics / Q000276:immunology; D032902:Ganoderma / Q000737:chemistry*; D006801:Humans; D007155:Immunologic Factors / Q000008:administration & dosage / Q000276:immunology*; D008264:Macrophages / Q000276:immunology; D051379:Mice; D009369:Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000276:immunology; D009569:Nitric Oxide / Q000276:immunology; D011134:Polysaccharides / Q000008:administration & dosage / Q000276:immunology*; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D016207:Cytokines; D007155:Immunologic Factors; D011134:Polysaccharides; D009569:Nitric Oxide