Immunomodulating activity of the polysaccharide TLH-3 from Tricholomalobayense in RAW264.7 macrophages

Polysaccharide TLH-3 extracted from Tricholoma lobayense possessed unique antioxidant and anti-aging activities, whereas its immunomodulatory properties remain unexplored. Herein in order to explore TLH-3 biological activities, the immunomodulatory effects on RAW264.7 macrophages and its molecular mechanisms were investigated. It was showed that TLH-3 could significantly enhance the phagocytic activity, releasing toxic molecules NO (nitricoxide), secretion of the cytokine TNF-?(tumor necrosis factor-?, IL-6 (interleukin-6). Further, TNF-?and IL-6 were blocked by the inhibitor of TLR4 (Toll-like receptor4), suggesting TLR4 was a receptor of TLH-3, and immunomodulatory activity of TLH-3 was mediated by TLR4. Moreover, immunofluorescence indicated that TLH-3 lead to the nuclear translocation of NF-?B (nuclear factor-?B) subunit p65. Western blotting demonstrated that NF-?B levels in nucleuses increased and cytoplasmic I?B-?(inhibitor of NF-?B) degraded after TLH-3 treatment, suggesting that TLH-3 probably stimulated macrophage by activating the IKB-alpha-NF-kappa B pathway via TLR-4. This study demonstrated that TLH-3 could be potentially used as immunomodulatory agent for healthcare and disease control. (C) 2017 Elsevier B.V. All rights reserved.