College of Pharmacy, University of Hawaii, Hawaii, Hilo 96720, USA.
Nat Prod Res. 2010 Nov;24(18):1758-65. doi: 10.1080/14786410903335232.
Gallic acid (3,4,5-trihydroxybenzoic acid), found in many plants either in free-form or part of tannins, is known to possess anti-microbial, antioxidant and cytotoxic properties. NFκB regulates the expression of several genes involved in carcinogenesis. These include anti-apoptotic, cytokines and cell cycle-regulatory genes. It is well established that the transcriptional factor NFκB is deregulated in many forms of cancer. Thus, agents that can suppress NFκB activation have the potential of suppressing carcinogenesis. In the present investigation, gallic acid was isolated from Alchornea glandulosa (Euphorbiaceae) and eight esters were synthesised. These compounds were evaluated against TNF-α-induced NFκB activation with stably transfected 293/NFκB-Luc human embryonic kidney cells. Gallates with IC(50) values in a range of 10-56 µM mediated inhibitory activity higher than gallic acid (IC(50) 76.0 ± 4.9 µM). In addition to inhibiting NFκB activation, gallic acid mediated a modest cytotoxic effect, and some of the gallates affected cell viability at the tested concentrations. Based on these results, suppression of NFκB activation by gallate esters could play a chemopreventive role in carcinogenesis.
没食子酸（3,4,5-三羟基苯甲酸），存在于许多植物中，或以游离形式或以单宁的一部分存在，具有抗微生物、抗氧化和细胞毒性的特性。NFκB 调节参与癌变的几个基因的表达。这些基因包括抗凋亡、细胞因子和细胞周期调节基因。已经证实，转录因子 NFκB 在许多形式的癌症中失调。因此，能够抑制 NFκB 激活的试剂有可能抑制癌变。在本研究中，从 Alchornea glandulosa（大戟科）中分离出没食子酸，并合成了 8 种酯。这些化合物在转染稳定的 293/NFκB-Luc 人胚肾细胞中用 TNF-α 诱导 NFκB 激活进行了评估。没食子酸酯的 IC（50）值在 10-56µM 范围内，介导的抑制活性高于没食子酸（IC（50）为 76.0±4.9µM）。除了抑制 NFκB 激活外，没食子酸还介导适度的细胞毒性作用，并且一些没食子酸酯在测试浓度下影响细胞活力。基于这些结果，没食子酸酯抑制 NFκB 激活可能在癌变的化学预防中发挥作用。
