Polysaccharides from the Medicinal Mushroom Cordyceps taii Show Antioxidant and Immunoenhancing Activities in a D-Galactose-Induced Aging Mouse Model.

Cordyceps taii, an edible medicinal mushroom native to south China, is recognized as an unparalleled resource of healthy foods and drug discovery. In the present study, the antioxidant pharmacological properties of C. taii were systematically investigated. In vitro assays revealed the scavenging activities of the aqueous extract and polysaccharides of C. taii against various free radicals, that is, 1,1-diphenyl-2-picrylhydrazyl radical, hydroxyl radical, and superoxide anion radical. The EC(50) values for superoxide anion-free radical ranged from 2.04 mg/mL to 2.49 mg/mL, which was at least 2.6-fold stronger than that of antioxidant thiourea. The polysaccharides also significantly enhanced the antioxidant enzyme activities (superoxide dismutase, catalase, and glutathione peroxidase) and markedly decreased the malondialdehyde production of lipid peroxidation in a D-galactose-induced aging mouse model. Interestingly, the immune function of the administration group was significantly boosted compared with the D-galactose-induced aging model group. Therefore, the C. taii polysaccharides possessed potent antioxidant activity closely associated with immune function enhancement and free radical scavenging. These findings suggest that the polysaccharides are a promising source of natural antioxidants and antiaging drugs. Consequently, a preliminary chemical investigation was performed using gas chromatography-mass spectroscopy and revealed that the polysaccharides studied were mainly composed of glucose, mannose, and galactose. Fourier-transform infrared spectra also showed characteristic polysaccharide absorption bands.

[Antimicrobial potential of Metarhizium taii in vitro].

OBJECTIVE: To investigate the antimicrobial potential of Metarhizium tail and its corresponding active fractions. METHODS: The agar diffusion method and growth-rate assay were employed individually to measure the antibacterial and antifungal activities of M. taii. The microdilution and disk colony count was used to test the minimal inhibitory concentration and minimal bacterial concentration. RESULTS: The extraction fractions of M. tail could evidently inhibi the growth of Gram positive bacteria such as Staphylococcus aureus, Bacillus subtilis, Gram negative bacteria such as Escherichia coli, Pseudomonas aerzginosa, and Klebsiella pneumoniae, and Enterococcus faecalis,and phytopathogenic fungi such as Rhizoctonia solani, Fusarium oxysporum, hereby M. taii had a broad spectrum antimicrobial effect including potent antibacterial and antifungal activities. The antimicrobial active ingredients of M. tail mainly existed in three extraction fractions including ethyl acetate extract in fermented broth, chloroform, and ethyl acetate extracts in mycelia. However there was an evident discrepancy on the antibacterial spectrum and competence for different active extraction fractions. CONCLUSION: M. taii possess potent and broad-spectrum antimicrobial potential, and it is a good edible and medicinal resource for the functional food development and the discovery of new antimicrobial drug.

[The change of CD4+ CD25high CCR6+ regulatory T cells in breast cancer patients].

OBJECTIVE: To detect the proportion of CD4+ CD25high CCR6+ regulatory T cells in peripheral blood mononuclear cells and tumor infiltration lymphocytes from breast cancer patients and explore its significance. METHODS: Lymphocytes isolated from blood and tumor mass of breast cancer patients were analyzed for the proportion of CD4+ CD25high CCR6+ regulatory T cells by flow cytometry. The expression of Foxp3 on CD4+ CD25high CCR6+ regulatory T cells, as well as CD45RO, CD44 and CD62L, were also analyzed. The effects of CD4+ CD25high CCR6+ regulatory T cells on the proliferation of CD4+ CD25- T cells also were detected by 3H-incorporation assay. RESULTS: Compared to the control, increased proportion of CD4+ CD25high CCR6+ regulatory T cells was observed in PBMCs and TILs from breast cancer patients. Moreover, CD4+ CD25high CCR6+ regulatory T cells, expressing high level of Foxp3, displayed effector memory phenotype determined by high level expression of CD45RO, CD44 and low level of CD62L. In addition, CD4+ CD25high CCR6+ regulatory T cells could inhibit the proliferation of CD4+ CD25- T cells in vitro. CONCLUSION: The enrichment of CD4+ CD25high CCR6+ regulatory T cells in tumor mass in breast cancer patients, which might be close related to long term immunoescape of tumor.