Department of Cardiology, The Second Affiliated Hospital, Xi'-an Jiaotong University School of Medicine, Xi-an, China.
Acta Pharmacol Sin. 2013 Jul;34(7):901-11. doi: 10.1038/aps.2013.24. Epub 2013 May 6.
To investigate whether curcumin (Cur) suppressed lipopolysaccharide (LPS)-induced inflammation in vascular smooth muscle cells (VSMCs) of rats, and to determine its molecular mechanisms.
Primary rat VSMCs were treated with LPS (1 μg/L) and Cur (5, 10, or 30 μmol/L) for 24 h. The levels of MCP-1, TNF-α, and iNOS were measured using ELISA and real-time RT-PCR. NO level was analyzed with the Griess reaction. Western-blotting was used to detect the activation of TLR4, MAPKs, IκBα, NF-κB p65, and the p47(phox) subunit of NADPH oxidase in the cells.
Treatment of VSMCs with LPS dramatically increased expression of inflammatory cytokines MCP-1 and TNF-α, expression of TLR4 and iNOS, and NO production. LPS also significantly increased phosphorylation of IκBα, nuclear translocation of NF-κB (p65) and phosphorylation of MAPKs in VSMCs. Furthermore, LPS significantly increased production of intracellular ROS, and decreased expression of p47(phox) subunit of NADPH oxidase. Pretreatment with Cur concentration-dependently attenuated all the aberrant changes in LPS-treated VSMCs. The LPS-induced overexpression of MCP-1 and TNF-α, and NO production were attenuated by pretreatment with the ERK inhibitor PD98059, the p38 MAPK inhibitor SB203580, the NF-κB inhibitor PDTC or anti-TLR4 antibody, but not with the JNK inhibitor SP600125.
Cur suppresses LPS-induced overexpression of inflammatory mediators in VSMCs in vitro via inhibiting the TLR4-MAPK/NF-κB pathways, partly due to block of NADPH-mediated intracellular ROS production.
探讨姜黄素（Cur）是否抑制脂多糖（LPS）诱导的大鼠血管平滑肌细胞（VSMCs）炎症，并确定其分子机制。
用 LPS（1μg/L）和 Cur（5、10 或 30μmol/L）处理原代大鼠 VSMCs 24 小时。用 ELISA 和实时 RT-PCR 检测 MCP-1、TNF-α 和 iNOS 的水平。用 Griess 反应分析 NO 水平。用 Western-blotting 检测细胞中 TLR4、MAPKs、IκBα、NF-κB p65 和 NADPH 氧化酶 p47（phox）亚基的激活。
用 LPS 处理 VSMCs 可显著增加炎症细胞因子 MCP-1 和 TNF-α的表达、TLR4 和 iNOS 的表达以及 NO 的产生。LPS 还可显著增加 IκBα的磷酸化、NF-κB（p65）的核转位和 VSMCs 中 MAPKs 的磷酸化。此外，LPS 可显著增加细胞内 ROS 的产生，并降低 NADPH 氧化酶 p47（phox）亚基的表达。Cur 浓度依赖性地减弱了 LPS 处理的 VSMCs 中的所有异常变化。用 ERK 抑制剂 PD98059、p38 MAPK 抑制剂 SB203580、NF-κB 抑制剂 PDTC 或抗 TLR4 抗体预处理可减弱 LPS 诱导的 MCP-1 和 TNF-α的过度表达和 NO 的产生，但 JNK 抑制剂 SP600125 则没有。
Cur 通过抑制 TLR4-MAPK/NF-κB 途径抑制 LPS 诱导的 VSMCs 中炎症介质的过度表达，部分原因是阻断 NADPH 介导的细胞内 ROS 产生。
