Pleurotus nebrodensis polysaccharide (PN-S) enhances the immunity of immunosuppressed mice / 中国天然药物

In the present study, the effects of Pleurotus nebrodensis polysaccharide (PN-S) on the immune functions of immunosuppressed mice were determined. The immunosuppressed mouse model was established by treating the mice with cyclophosphamide (40 mg/kg/2d, CY) through intraperitoneal injection. The results showed that PN-S administration significantly reversed the CY-induced weight loss, increased the thymic and splenic indices, and promoted proliferation of T lymphocyte, B lymphocyte, and macrophages. PN-S also enhanced the activity of natural killer cells and increased the immunoglobulin M (IgM) and immunoglobulin G (IgG) levels in the serum. In addition, PN-S treatment significantly increased the phagocytic activity of mouse peritoneal macrophages. PN-S also increased the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), and nitric oxide (NOS) in splenocytes. qRT-PCR results also indicated that PN-S increased the mRNA expression of IL-6, TNF-α, INF-γ, and nitric oxide synthase (iNOS) in the splenocytes. These results suggest that PN-S treatment enhances the immune function of immunosuppressed mice. This study may provide a basis for the application of this fungus in adjacent immunopotentiating therapy against cancer and in the treatment of chemotherapy-induced immunosuppression.

The polysaccharide isolated from Pleurotus nebrodensis (PN-S) shows immune-stimulating activity in RAW264.7 macrophages / 中国天然药物

A novel Pleurotus nebrodensis polysaccharide (PN-S) was purified and characterized, and its immune-stimulating activity was evaluated in RAW264.7 macrophages. PN-S induced the proliferation of RAW264.7 cells in a dose-dependent manner, as determined by the MTT assay. After exposure to PN-S, the phagocytosis of the macrophages was significantly improved, with remarkable changes in morphology being observed. Flow cytometric analysis demonstrated that PN-S promoted RAW264.7 cells to progress through S and G2/M phases. PN-S treatment enhanced the productions of interleukin-6 (IL-6), nitric oxide (NO), interferon gamma (INF-γ), and tumor necrosis factor-α (TNF-α) in the macrophages, with up-regulation of mRNA expressions of interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), interferon gamma(INF-γ) and tumor necrosis factor-α (TNF-α) being observed in a dose-dependent manner, as measured by qRT-PCR. In conclusion, these results suggest that the purified PN-S can improve immunity by activating macrophages.

Anticancer and Immunopotentiating Activities of Crude Polysaccharides from Pleurotus nebrodensis on Mouse Sarcoma 180

Pleurotus nebrodensis is an edible and commercially available mushroom in Korea. This study was conducted in order to evaluate the anticancer and immunopotentiating activities of crude polysaccharides, extracted in methanol, neutral saline, and hot water (hereafter referred to as Fr. MeOH, Fr. NaCl, and Fr. HW, respectively) from the fruiting bodies of P. nebrodensis. beta-Glucan and protein contents in Fr. MeOH, Fr. NaCl, and Fr. HW extracts of P. nebrodensis ranged from 23.79~36.63 g/100 g and 4.45~6.12 g/100 g, respectively. Crude polysaccharides were not cytotoxic against sarcoma 180, HT-29, NIH3T3, and RAW 264.7 cell lines at a range of 10~2,000 microg/mL. Intraperitoneal injection with crude polysaccharides resulted in a life prolongation effect of 11.76~27.06% in mice previously inoculated with sarcoma 180. Treatment with Fr. NaCl resulted in an increase in the numbers of spleen cells by 1.49 fold at the concentration of 50 microg/mL, compared with control. Fr. HW improved the immuno-potentiating activity of B lymphocytes through an increase in alkaline phosphatase activity by 1.65 fold, compared with control at 200 microg/mL. Maximum production of nitric oxide (14.3 microM) was recorded in the Fr. NaCl fraction at 200 microg/mL. Production of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6) was significantly higher, compared to control, and IL-6 production was highest, in contrast to TNF-alpha, IL-1beta, and positive control, concanavalin at the tested concentration of the various fractions. Results of the current study suggest that polysaccharides extracted from P. nebrodensis have a strong anticancer effect and may be useful as an ingredient of biopharmaceutical products for treatment of cancer.

Phylogenetic Relationship in Different Commercial Strains of Pleurotus nebrodensis Based on ITS Sequence and RAPD

The molecular phylogeny in nine different commercial cultivated strains of Pleurotus nebrodensis was studied based on their internal transcribed spacer (ITS) region and RAPD. In the sequence of ITS region of selected strains, it was revealed that the total length ranged from 592 to 614 bp. The size of ITS1 and ITS2 regions varied among the strains from 219 to 228 bp and 211 to 229 bp, respectively. The sequence of ITS2 was more variable than ITS1 and the region of 5.8S sequences were identical. Phylogenetic tree of the ITS region sequences indicated that selected strains were classified into five clusters. The reciprocal homologies of the ITS region sequences ranged from 99 to 100%. The strains were also analyzed by RAPD with 20 arbitrary primers. Twelve primers were efficient to applying amplification of the genomic DNA. The sizes of the polymorphic fragments obtained were in the range of 200 to 2000 bp. RAPD and ITS analysis techniques were able to detect genetic variation among the tested strains. Experimental results suggested that IUM-1381, IUM-3914, IUM-1495 and AY-581431 strains were genetically very similar. Therefore, all IUM and NCBI gene bank strains of P. nebrodensis were genetically same with some variations.