Graduate Institute of Food Science and Technology, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan.
J Agric Food Chem. 2010 Feb 24;58(4):2596-601. doi: 10.1021/jf904356q.
Allergy is an immune dysfunction caused by degranulation from mast cells in the early phase and cytokine secretion in the late phase of the cell. The purpose of this study was to investigate the effects of adlay (Job's tears, Coix lachryma-jobi L. var. ma-yuen Stapf) testa against beta-hexosaminidase release as a marker of degranulation in rat basophilic leukemia (RBL)-2H3 cells. The ethyl acetate fraction from ethanolic extracts of adlay testa (ATE-EtOAc) exhibited potent inhibitory activity that suppressed degranulation from RBL-2H3 cells stimulated by 1 microM A23187. The 20%-80% EtOAc/Hex subfractions of ATE-EtOAc significantly inhibited histamine release with a IC(50) of 75-100 microg/mL. In addition, the ATE-EtOAc subfractions suppressed interleukin (IL)-4, IL-6, and tumor necrosis factor-alpha secretion in RBL-2H3 cells, indicating that adlay testa were able to inhibit cytokine secretion. In order to explore the inhibitory mechanism of adlay testa in mast cell degranulation, we examined the activation of intracellular signaling molecules. Adlay testa inhibited the phosphorylation ERK expression. Furthermore, the two major active compounds, 4-hydroxyacetophenone and p-coumaric acid, were isolated from the ATE-EtOAc subfractions. These results suggest that ATE had an inhibitory effect on allergic response via the ERK signaling transduction in RBL-2H3 cells.
过敏是一种免疫功能紊乱，由肥大细胞在细胞早期脱颗粒和晚期细胞因子分泌引起。本研究旨在探讨薏苡种皮（薏苡，薏苡薏苡 L. var. ma-yuen Stapf）对β-己糖胺酶释放的影响，β-己糖胺酶释放是大鼠嗜碱性白血病（RBL）-2H3 细胞脱颗粒的标志物。薏苡种皮的乙酸乙酯提取物（ATE-EtOAc）的乙酸乙酯部分表现出抑制由 1μM A23187 刺激的 RBL-2H3 细胞脱颗粒的强烈抑制活性。ATE-EtOAc 的 20%-80% EtOAc/Hex 亚部分以 75-100μg/mL 的 IC（50）显著抑制组胺释放。此外，ATE-EtOAc 亚部分抑制 RBL-2H3 细胞中白细胞介素（IL）-4、IL-6 和肿瘤坏死因子-α的分泌，表明薏苡种皮能够抑制细胞因子的分泌。为了探讨薏苡种皮在肥大细胞脱颗粒中的抑制机制，我们研究了细胞内信号分子的激活。薏苡种皮抑制 ERK 表达的磷酸化。此外，从 ATE-EtOAc 亚部分分离出两种主要的活性化合物，4-羟基苯乙酮和对香豆酸。这些结果表明，ATE 通过 RBL-2H3 细胞中的 ERK 信号转导对过敏反应具有抑制作用。
