Graduate Institute of Food Science and Technology, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan.
J Ethnopharmacol. 2012 May 7;141(1):119-27. doi: 10.1016/j.jep.2012.02.009. Epub 2012 Feb 14.
Adlay (Job's tears, Coix lachryma-jobi L. var. ma-yuen Stapf) has long been used in China to treat rheumatism.
We investigated the anti-allergic effects of adlay bran on rat basophilic leukemia (RBL)-2H3 cells.
To evaluate the anti-allergic effects of adlay bran, the release of histamines and cytokines were measured using ELISA. To explore the mechanism of these effects, the protein expression levels were determined using western blotting.
A 40.8μg/mL concentration of the ethyl acetate fraction of the ethanolic extracts of adlay bran (ABE-EtOAc) effectively inhibited mast cell degranulation. The 40-100% EtOAc/Hex subfractions of ABE-EtOAc inhibited histamine release with an IC(50) of 71-87μg/mL. Moreover, the ABE-EtOAc subfractions suppressed the secretion of interleukin (IL)-4, IL-6 and tumor necrosis factor-α in the RBL-2H3 cells, indicating that adlay bran can inhibit cytokine secretion in the late phase of the allergic reaction. In addition, adlay bran reduced the intracellular production of reactive oxygen species, inhibited the phosphorylation of Akt and decreased the expression of protein kinase C. Furthermore, six phenolic acids and one flavone were isolated. Of these compounds, luteolin showed the most potent inhibitory activity (IC(50)=1.5μg/mL).
Adlay bran extract reduced the release of histamines and cytokines and suppressed the production of Akt. These combined effects influenced the signal transduction in RBL-2H3 cells, thereby revealing the mechanisms of the anti-allergic effects of adlay.
薏苡仁（薏苡，Coix lachryma-jobi L. var. ma-yuen Stapf）在中国长期以来一直被用于治疗风湿病。
我们研究了薏苡仁糠对大鼠嗜碱性白血病（RBL-2H3）细胞的抗过敏作用。
为了评估薏苡仁糠的抗过敏作用，使用 ELISA 测量组氨酸和细胞因子的释放。为了探索这些作用的机制，使用蛋白质印迹法确定蛋白质表达水平。
40.8μg/mL 的薏苡仁糠醇提物的乙酸乙酯部分（ABE-EtOAc）可有效抑制肥大细胞脱粒。ABE-EtOAc 的 40-100% EtOAc/Hex 级分以 71-87μg/mL 的 IC50 抑制组胺释放。此外，ABE-EtOAc 级分抑制了 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，表明薏苡仁可以抑制过敏反应后期细胞因子的分泌。此外，薏苡仁糠降低了细胞内活性氧的产生，抑制了 Akt 的磷酸化并降低了蛋白激酶 C 的表达。此外，分离得到了六种酚酸和一种黄酮。其中，木犀草素显示出最强的抑制活性（IC50=1.5μg/mL）。
薏苡仁糠提取物减少了组氨酸和细胞因子的释放，并抑制了 Akt 的产生。这些综合作用影响了 RBL-2H3 细胞中的信号转导，从而揭示了薏苡仁抗过敏作用的机制。
