Institute of Natural Science, Keimyung University, Daegu 42601, Korea.
Department of Applied Chemistry, Kumoh National Institute of Technology, Gumi 39177, Korea.
Molecules. 2020 Apr 29;25(9):2084. doi: 10.3390/molecules25092084.
Tricin, a flavone present in rice bran, is confirmed as the major efficacious compound present in the enzyme-treated extract (ETZL), which protects against UVB-induced skin-aging. However, the suppressive mechanism of tricin on allergic responses remains unknown. The present study, therefore, aimed to determine the mechanisms of tricin and ETZL on mast cell degranulation in IgE-activated rat basophilic leukemia cell line (RBL-2H3) cells. We investigated the regulatory effects of tricin and ETZL on degranulation, production of cytokines and lipid mediators, and signaling proteins involved in the IgE-bound high-affinity IgE receptor activation, mitogen-activated protein kinase, arachidonic acid and Syk. The production of β-hexosaminidase, tumor necrosis factor-α, interleukin-4, leukotrienes (LT) B, LTC and prostaglandin E in IgE-stimulated RBL-2H3 cells were significantly inhibited by exposure to tricin or ETZL. Moreover, tricin and ETZL inhibit the phosphorylation of cytosolic phospholipase A2, 5-lipoxygenase and cyclooxygenase-2. Furthermore, the phosphorylation of Akt, ERK, p38, JNK, protein kinase Cδ and phospholipase Cγ1 were effectively suppressed by both samples. Exposure to tricin or ETZL also significantly decreases the phosphorylation of Lyn and Syk, but has minimal effect on Fyn. Taken together, our data indicate that tricin and ETZL are potential anti-allergic materials that could be applied for the prevention of allergy-related diseases.
浮萍素，一种存在于米糠中的类黄酮，已被证实为酶处理提取物（ETZL）中具有保护作用的主要有效化合物，可预防 UVB 诱导的皮肤衰老。然而，浮萍素对过敏反应的抑制机制尚不清楚。因此，本研究旨在确定浮萍素和 ETZL 对 IgE 激活的大鼠嗜碱性白血病细胞系（RBL-2H3）细胞中肥大细胞脱颗粒的作用机制。我们研究了浮萍素和 ETZL 对脱颗粒、细胞因子和脂质介质产生以及涉及 IgE 结合高亲和力 IgE 受体激活、丝裂原活化蛋白激酶、花生四烯酸和 Syk 的信号蛋白的调节作用。β-己糖胺酶、肿瘤坏死因子-α、白细胞介素-4、白三烯（LT）B、LTC 和前列腺素 E 在 IgE 刺激的 RBL-2H3 细胞中的产生，通过暴露于浮萍素或 ETZL 而显著受到抑制。此外，浮萍素和 ETZL 抑制细胞质磷脂酶 A2、5-脂氧合酶和环氧化酶-2 的磷酸化。此外，两种样品还能有效抑制 Akt、ERK、p38、JNK、蛋白激酶 Cδ 和磷脂酶 Cγ1 的磷酸化。暴露于浮萍素或 ETZL 还显著降低 Lyn 和 Syk 的磷酸化，但对 Fyn 的影响最小。综上所述，我们的数据表明浮萍素和 ETZL 是潜在的抗过敏物质，可用于预防与过敏相关的疾病。
