Kawai Junya, Higuchi Yuka, Hirota Mitsuru, Hirasawa Noriyasu, Mori Koichiro
a Mushroom Research Laboratory , Hokuto Corporation , Nagano , Japan.
b Department of Bioscience and Biotechnology, Faculty of Agriculture , Shinshu University , Kami-ina , Nagano , Japan.
Biosci Biotechnol Biochem. 2018 Oct;82(10):1803-1811. doi: 10.1080/09168451.2018.1490169. Epub 2018 Jul 2.
Grifola frondosa is an edible mushroom consumed as a health food and/or traditional medicine in Asia. However, the anti-allergic effects of G. frondosa are not yet understood. In this study, we demonstrated the effects of G. frondosa extract (GFE) on IgE-mediated allergic responses, using antigen-stimulated RBL-2H3 cells. Three active compounds: ergosterol, 6β-methoxyergosta-7,22-dien-3β,5α-diol (MEDD), and 6-oxoergosta-7,22-dien-3β-ol (6-OXO) were isolated from GFE and shown to inhibit the antigen-induced release of β-hexosaminidase and histamine. Among the three active components, we focused on ergosterol because of its high content in GFE. Ergosterol inhibited the aggregation of high-affinity IgE receptor (FcεRI), which is the first step in the activation of mast cells and antigen-induced tyrosine phosphorylation. Furthermore, ergosterol suppressed antigen-increased IL-4 and TNF-α mRNA. Taken together, our findings suggest that G. frondosa, including ergosterol and its derivatives as active components, has the potential to be a novel functional food that prevents type I allergies.
灰树花是一种可食用蘑菇，在亚洲被作为健康食品和/或传统药物食用。然而，灰树花的抗过敏作用尚不清楚。在本研究中，我们使用抗原刺激的RBL-2H3细胞，证明了灰树花提取物（GFE）对IgE介导的过敏反应的影响。从GFE中分离出三种活性化合物：麦角甾醇、6β-甲氧基麦角甾-7,22-二烯-3β,5α-二醇（MEDD）和6-氧代麦角甾-7,22-二烯-3β-醇（6-OXO），它们可抑制抗原诱导的β-己糖胺酶和组胺释放。在这三种活性成分中，我们重点关注麦角甾醇，因为它在GFE中的含量很高。麦角甾醇抑制高亲和力IgE受体（FcεRI）的聚集，这是肥大细胞活化和抗原诱导的酪氨酸磷酸化的第一步。此外，麦角甾醇抑制抗原诱导的IL-4和TNF-α mRNA增加。综上所述，我们的研究结果表明，包括麦角甾醇及其衍生物作为活性成分的灰树花，有可能成为预防I型过敏的新型功能性食品。
