The investigation of immunomodulatory activities of Gloeostereum incaratum polysaccharides in cyclophosphamide-induced immunosuppression mice

Abstract

Gloeostereum incarnatum, a precious edible mushroom, displays anti-bacterial and anti-inflammatory activities; however, its immunomodulatory effect has not been studied yet. The present study aimed to investigate whether polysaccharide compositions of G. incarnatum polysaccharides (GIPS) possess immunomodulatory and immuno-enhancing effects in a Cyclophosphamide monohydrate (CTX)-induced BALB/c mice model. The 28-day GIPS administration at doses of 0.1, 0.3 and 0.9 g/kg remarkably reversed the bodyweight loss, increased the thymic index and promoted T lymphocyte proliferation in CTX-induced immunosuppressed mice. GIPS significantly raised the serum levels of immunoglobulin (Ig)A and IgG, promoted the production of interleukins (ILs), including IL-2, IL-3 and IL-6, interferons, including interferon (IFN)-α and IFN-γ, and monocyte chemotactic protein 1 in the spleen, which resulted in accelerating recovery of immunosuppression. Finally, GIPS showed anti-oxidative effects indicated by the increased superoxide dismutase levels in the serum and spleen, and the reduced level of reactive oxygen species in the spleen. The results of the current study demonstrated that GIPS positively adjusts the immune system, which may serve as a potential immunostimulatory agent.

Keywords: Gloeostereum incaratum; cyclophosphamide; immunomodulatory effect; oxidative stress; polysaccharides.

Figure 1.

(A) The Scheme for extraction and isolation of polysaccharides from G. incarnatum. (B) DEAE-Sepharose fast flow chromatogram of the crude polysaccharides.

Figure 2.

GIPS enhanced the lymphocyte proliferation of spleen in CTX-induced immunosuppressed mice. Data were expressed as means ± SEM (n=12). ^###P<0.001 vs. control group, *P<0.05 vs. model group. CTX, Cyclophosphamide; GIPS, G. incarnatum polysaccharides; Tα1, Thymosin α1.

Figure 3.

The regulatory effects of GIPS (0.1, 0.3 and 0.9 g/kg) and Tα1 (0.16 mg/kg) on the levels of (A) IgA, (B) IgG and (C) IgM in serum and spleen of CTX-induced immunosuppressed mice. Data were expressed as means ± SEM (n=12). ^##P<0.01 and ^###P<0.001 vs. control group, *P<0.05 and **P<0.01 vs. model group. CTX, Cyclophosphamide; GIPS, G. incarnatum polysaccharides; Tα1, Thymosin α1.