Graduate Institute of Sports and Health, National Changhua University of Education, Changhua County, Taiwan.
J Cell Physiol. 2010 May;223(2):389-96. doi: 10.1002/jcp.22047.
Tumor necrosis factor-alpha (TNF-alpha) is a pleiotropic cytokine produced by activated macrophages. IL-6 is a multifunctional cytokine that plays a central role in both innate and acquired immune responses. We investigated the signaling pathway involved in IL-6 production stimulated by TNF-alpha in cultured myoblasts. TNF-alpha caused concentration-dependent increases in IL-6 production. TNF-alpha-mediated IL-6 production was attenuated by focal adhesion kinase (FAK) mutant and siRNA. Pretreatment with phosphatidylinositol 3-kinase inhibitor (PI3K; Ly294002 and wortmannin), Akt inhibitor, NF-kappaB inhibitor (pyrrolidine dithiocarbamate, PDTC), and IkappaB protease inhibitor (L-1-tosylamido-2-phenyl phenylethyl chloromethyl ketone, TPCK) also inhibited the potentiating action of TNF-alpha. TNF-alpha increased the FAK, PI3K, and Akt phosphorylation. Stimulation of myoblasts with TNF-alpha activated IkappaB kinase alpha/beta (IKKalpha/beta), IkappaBalpha phosphorylation, p65 phosphorylation, and kappaB-luciferase activity. TNF-alpha mediated an increase of kappaB-luciferase activity which was inhibited by Ly294002, wortmannin, Akt inhibitor, PDTC and TPCK or FAK, PI3K, and Akt mutant. Our results suggest that TNF-alpha increased IL-6 production in myoblasts via the FAK/PI3K/Akt and NF-kappaB signaling pathway.
肿瘤坏死因子-α（TNF-α）是一种由激活的巨噬细胞产生的多效细胞因子。白细胞介素-6（IL-6）是一种多功能细胞因子，在固有和获得性免疫反应中都起着核心作用。我们研究了 TNF-α刺激培养的成肌细胞产生 IL-6 所涉及的信号通路。TNF-α引起 IL-6 产生的浓度依赖性增加。FAK 突变体和 siRNA 可减弱 TNF-α介导的 IL-6 产生。PI3K 抑制剂（PI3K；Ly294002 和wortmannin）、Akt 抑制剂、NF-κB 抑制剂（吡咯烷二硫代氨基甲酸盐，PDTC）和 IkappaB 蛋白酶抑制剂（L-1-对甲苯磺酰基-2-苯丙氨酸氯甲基酮，TPCK）预处理也抑制了 TNF-α的增强作用。TNF-α增加了 FAK、PI3K 和 Akt 的磷酸化。TNF-α刺激成肌细胞激活 IkappaB 激酶α/β（IKKα/β）、IκBα磷酸化、p65 磷酸化和κB-荧光素酶活性。TNF-α介导的κB-荧光素酶活性增加被 Ly294002、wortmannin、Akt 抑制剂、PDTC 和 TPCK 或 FAK、PI3K 和 Akt 突变体抑制。我们的结果表明，TNF-α通过 FAK/PI3K/Akt 和 NF-κB 信号通路增加成肌细胞中的 IL-6 产生。
