铁观音茶提取物对脂多糖诱导RAW264.7细胞炎症反应的抑制作用及机制

研究铁观音茶提取物对脂多糖(LPS)诱导的RAW264.7细胞炎症反应的抑制作用及机制。用脂多糖作用于RAW264.7细胞,建立炎症模型,并用吲哚美辛和不同浓度铁观音提取物处理,检测NO和IL-6的分泌情况,qPCR检测一氧化氮合酶(iNOS)、环氧合酶2(COX-2)、肿瘤坏死因子α(TNF-α)、单核细胞趋化蛋白1(MCP-1)、白细胞介素6(IL-6)mRNA相对表达,Western Blot检测炎症相关蛋白激酶(IKKβ),核转录因子κB抑制因子(IκB)、核转录因子κB p65(NF κB p65)及其磷酸化产物的相对表达。结果显示,铁观音茶提取物能显著抑制炎症介质NO分泌和IL-6蛋白表达量(p<0.05),抑制炎症相关基因iNOS、COX-2、TNF-α和MCP-1等表达,并极显著抑制NF-κB信号通路相关蛋白IKKβ、IkB和p65的磷酸化(p<0.01)。以上结果表明,铁观音茶提取物可明显抑制LPS诱导的RAW264.7细胞炎症反应,其机制可能与抑制NF-κB信号通路激活有关。

Inhibitory Effects and Mechanism of Tieguanyin Tea Extracts on LPS-induced Inflammatory Response in RAW264.7 Cells

The aim of this study was to investigate the inhibitory effects and the potential mechanism of Tieguanyin tea extracts on LPS-induced inflammatory response in RAW264.7 cells. Lipopolysaccharide was applied to RAW264.7 cells to establish an inflammatory model, and treated with indomethacin and different concentrations of Tieguanyin tea extract. Detected the secretion of NO and IL-6, qPCR was used to detected the gene expression of nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), tumor necrosis factor α (TNF-α), monocyte chemoattractant protein 1 (MCP-1) and interleukin-6 (IL-6). Western Blot was used to detect the relative expression of inflammation-associated protein kinase (IKKβ), nuclear factor κB inhibitor (IκB), nuclear factor κB p65 (NFκB p65) and its phosphorylated products. The results showed that Tieguanyin tea extracts could significantly decrease the secretions of NO and IL-6, the gene expressions of iNOS, COX-2, TNF-α, MCP-1 and IL-6, and the phosphorylations of IKKβ, IkB and p65. In summary, Tieguanyin tea extracts significantly inhibit the LPS-induced inflammatory response of RAW264.7 cells, which may be related with the inhibition of NF-κB signaling pathway.