Alginate enhances Toll-like receptor 4-mediated phagocytosis by murine RAW264.7 macrophages
Alginate enhances Toll-like receptor 4-mediated phagocytosis by murine RAW264.7 macrophages
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藻酸盐可增强小鼠RAW264.7巨噬细胞中Toll样受体4介导的吞噬作用
DOI：
10.1016/j.ijbiomac.2017.07.129
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发表时间：
2017-12-01
影响因子：
8.2
通讯作者：
Xu, Xu
中科院分区：
文献类型：
--
作者：
Bi, Decheng;Zhou, Rui;Xu, Xu
海藻酸盐是一种天然酸性多糖，由β-D-甘露糖酸和α-L-古糖醛酸交替组成，具有1，4-糖苷键，来源于棕色海藻。本实验研究了藻酸盐对小鼠RAW264.7细胞巨噬细胞吞噬功能的促进作用及其分子机制。海藻酸盐能增强金纳米颗粒(AuNPs)、荧光微球和免疫球蛋白G(Ig G)调理的金黄色葡萄球菌(S.aureus)的细胞内吞噬作用。此外，藻酸盐还能增加Toll样受体4(TLR4)的表达，并激活Akt/核因子-kappaB(NF-kappa B)和p38丝裂原活化蛋白激酶(MAPK)信号通路。TLR4、NF-kappa B和p38MAPK抑制剂的加入以及TLR4基因的敲除抑制了藻酸盐促进的吞噬作用，表明这些关键成分参与了吞噬作用。本工作首次提出藻酸盐通过上调TLR4的表达和刺激Akt/NF-kappaB和p38MAPK信号通路促进吞噬功能，这可能有助于藻酸盐激活巨噬细胞的能力。(C)2017年，由爱思唯尔出版。
Alginate is a naturally acidic polysaccharide consisting alternately of beta-D-mannuronic acid and alpha-L-guluronic acid with 1, 4-glycosidic linkages and is derived from brown seaweeds. Herein, the effect of alginate on the promotion of macrophage phagocytosis and the corresponding molecular mechanisms were investigated in murine RAW264.7 cells. Alginate could enhance the intracellular phagocytosis of gold nanoparticles (AuNPs), fluorescent microspheres and immunoglobulin G (IgG)-opsonized Staphylococcus aureus (S. aureus). Moreover, alginate increased Toll-like receptor 4 (TLR4) expression and activated the Akt/nuclear factor-kappa B (NF-kappa B) and p38 mitogen-activated protein kinase (MAPK) signalling pathways. Alginate-promoted phagocytosis was suppressed by the addition of inhibitors of TLR4, NF-kappa B and p38 MAPK and by TLR4 gene knockdown, indicating the involvement of these key components. This work is the first to propose that alginate promotes phagocytosis via upregulating TLR4 expression and stimulating the Akt/NF-kappa B and p38 MAPK signalling pathways, which may contribute to the capacity of alginate to activate macrophages. (C) 2017 Published by Elsevier B.V.