Extraction of Polysaccharides from Wild Hohenbuehelia serotina and Its Immunomodulatory Function in Raw264.7 Cells

Water soluble Hohenbuehelia serotina polysaccharides(HSP)was isolated and its immunomodulatory activities in macrophage Raw264.7 cells were evaluated in vitro. Macrophage proliferation was conducted by WST-1.NO concentration was analyzed by griess reagent. Tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β)and prostaglandins E2(PGE₂)was detected by ELISA. And transcriptional level of iNOS,COX-2,IL-6,TNF-α and IL-1β was determined by RT-qPCR. The results indicated that HSP could significantly stimulate intracellular nitric oxide(NO)concentration in Raw264.7 cells. When the concentration of HSP was 100.00 μg/mL,the secretion of NO reached to the maximum which was 30.4335 μmol/L. Compared with blank control,HSP could significantly increase cytokines in Raw264.7 cells such as the tumor necrosis factor-α(TNF-α),prostaglandin E₂(PGE₂)and interleukin-1β(IL-1β)levels,and its secretion of high dose group(29.94 pg/mL,1.8174 ng/mL)was similar to that in the LPS positive control group. The results of RT-qPCR analysis showed that HSP also could enhance inducible nitric oxide synthase(iNOS)and cyclooxygenase-2(COX-2)expression in Raw264.7 cells. These results suggested that HSP had potential immunomodulating activities and could be applied in functional food and medicine.