Bidirectional immunomodulating activity of fermented polysaccharides from Yupingfeng

Accumulating evidence has proven the immunomodulating activity of Yupingfeng. This study compared the immunomodulatory activity in vitro of the unfermented Yupingfeng dreg polysaccharides (UYDP) with that of the fermented Yupingfeng dreg polysaccharides (FYDP) obtained using Rhizopus oligosporus SH. Results consistently elucidated the duality of the immunomodulatory roles of UYDP and FYDP in regulating proliferation, and cytokines expressions in murine lymphocytes and macrophages. Compared with UYDP, FYDP effectively enhanced the proliferation of lymphocytes and promoted mRNA expression of inducible nitric oxide synthase (iNOS), IL-6, TNF-α, INF-γ, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and TLR-4 in lymphocytes and macrophages. Moreover, compared with UYDP, FYDP effectively normalized cell proliferation and downregulated mRNA expression levels of pro-inflammatory cytokines, NF-κB, TLR-4, and iNOs in lipopolysaccharide-induced chronic inflammation cells. The results revealed that the bidirectional immunomodulatory effects in vitro of UYDP and FYDP, and the bi-directional immunomodulatory activity of FYDP is superior over that of UYDP. Moreover, more studies in vivo that needs to be studied further. •UYDP and FYDP obtained by R. oligosporus play dual immunomodulatory roles in vitro.•The content of glucopyranoside in FYDP is more than UYDP.•FYDP treatment showed more remarkable dual immune activity than UYDP.