Key Laboratory of Food Processing Technology and Quality Control in Shandong Province, College of Food Science and Engineering, Shandong Agricultural University, Tai'an, China.
Center of Bee Industry on Seed-Breeding and Popularization in Shandong Province, Tai'an, China.
Phytother Res. 2019 Mar;33(3):756-767. doi: 10.1002/ptr.6268. Epub 2019 Jan 14.
The synergistic anti-inflammatory effect of quercetin and catechin was investigated using lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. Results showed that the combined treatment of quercetin with catechin synergistically attenuated LPS-stimulated increase of some proinflammatory molecules, including nitric oxide, tumor necrosis factor α, interleukin-1β, nitric oxide synthase, and cyclooxygenase-2. Moreover, it exhibited significantly (p < 0.05) stronger inhibitory effect on nuclear translocation of nuclear factor-κB (NF-κB) by suppressing the phosphorylation of NF-κB p65 and p50 submits and on the phosphorylation of ETS domain-containing protein and c-Jun N-terminal kinase than any of quercetin or catechin alone. Besides, the cotreatment of quercetin with catechin significantly (p < 0.05) restored the impaired expression of toll-like receptor 4, myeloid differentiation primary response gene 88, and some downstream effectors (IRAK1, TRAF6, and TAK1). These results suggest that quercetin and catechin possessed synergistic anti-inflammatory effects, which may be attributed to their roles in suppressing the activation of TLR4-MyD88-mediated NF-κB and mitogen-activated protein kinases signaling pathways.
采用脂多糖（LPS）刺激的巨噬细胞 RAW 264.7 细胞研究了槲皮素和儿茶素的协同抗炎作用。结果表明，槲皮素与儿茶素联合处理协同减弱了 LPS 刺激引起的一些促炎分子的增加，包括一氧化氮、肿瘤坏死因子-α、白细胞介素-1β、一氧化氮合酶和环加氧酶-2。此外，它通过抑制 NF-κB p65 和 p50 亚基的磷酸化以及 ETS 结构域包含蛋白和 c-Jun N-末端激酶的磷酸化，对核转录因子-κB（NF-κB）的核易位表现出显著（p<0.05）更强的抑制作用，而单独使用槲皮素或儿茶素则没有。此外，槲皮素与儿茶素的共同处理显著（p<0.05）恢复了 Toll 样受体 4、髓样分化初级反应基因 88 和一些下游效应物（IRAK1、TRAF6 和 TAK1）的表达受损。这些结果表明，槲皮素和儿茶素具有协同的抗炎作用，这可能归因于它们在抑制 TLR4-MyD88 介导的 NF-κB 和丝裂原激活蛋白激酶信号通路的激活中的作用。
