Laboratory of Nutrition Research, National Nutrition and Food Technology Research Institute and Faculty, Shaheed Beheshti University (M.C.), Tehran, Iran.
Int J Food Sci Nutr. 2009;60 Suppl 1:79-88. doi: 10.1080/09637480802158184. Epub 2008 Aug 4.
The effects of black tea extract (BTE) and some of its pure phenolics on human peripheral blood mononuclear cell (PBMC) cytokine secretion were examined in vitro.
The main steps of the study included chromatographic analysis of BTE and commercial green tea extract, Polyphenon 60, determination of the total antioxidant capacity of both the extracts and their phenolics, and finally evaluation of their effects on PBMCs.
Four major peaks in the chromatogram of BTE belonged to caffeine, gallic acid, epigallocatechin and epigallocatechin gallate, and the latter showed the highest antioxidant capacity. While pure phenolics at the concentration of 20 mM did not significantly affect PBMC cytokine secretion, BTE and Polyphenon 60 suppressed interleukin-1 beta, tumor necrosis factor-alpha and interleukin-6. Interestingly, the secretion of interferon-gamma after 24 h was slightly, but significantly, boosted by the extracts.
BTE has selective pro-inflammatory cytokine-suppressing effects on human PBMCs.
本研究旨在体外观察红茶提取物（BTE）及其部分纯酚类物质对人外周血单个核细胞（PBMC）细胞因子分泌的影响。
该研究的主要步骤包括 BTE 和市售绿茶提取物、多酚 60 的色谱分析，以及两种提取物及其酚类物质总抗氧化能力的测定，最后评估它们对 PBMC 的影响。
BTE 色谱图中的四个主要峰分别属于咖啡因、没食子酸、表没食子儿茶素和表没食子儿茶素没食子酸酯，后者显示出最高的抗氧化能力。虽然 20mM 浓度的纯酚类物质对 PBMC 细胞因子分泌没有显著影响，但 BTE 和多酚 60 抑制了白细胞介素-1β、肿瘤坏死因子-α和白细胞介素-6 的分泌。有趣的是，两种提取物在 24 小时后略微但显著地促进了干扰素-γ的分泌。
BTE 对人 PBMC 具有选择性的促炎细胞因子抑制作用。
