Bao Yuan, Wang Song, Gao Yang, Zhang Wen, Jin Haitao, Yang Yang, Li Jiangyu
Department of Network Medicine, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430014, P.R. China.
Department of Massage, Wuhan Hospital of Traditional Chinese Medicine, Wuhan, Hubei 430014, P.R. China.
Exp Ther Med. 2018 Sep;16(3):2763-2769. doi: 10.3892/etm.2018.6510. Epub 2018 Jul 23.
Mast cells (MCs) have been reported to serve a crucial role in allergic diseases, including asthma, allergic rhinitis and anaphylaxis. A previous study revealed that microRNA-126 (miR-126) was associated with airway hyperresponsiveness induced by house dust mites, however the molecular mechanisms were unclear. The present study aimed to investigate the effect of miR-126 on immunoglobulin E (IgE)-regulated MC degranulation and explore its underlying mechanisms. miR-126 expression was quantified using a rat model and in rat peritoneal mast cells (RPMCs) . Overexpression or downregulation of miR-126 was established by transfection with miR-126 mimics or miR-126 inhibitors and MC degranulation was subsequently evaluated. The effect of miR-126 on protein kinase B (Akt) and phosphorylated Akt protein expression was examined by western blot analysis. The phosphoinositide 3-kinase (PI3K) inhibitor (LY294002) was used to determine the role of the PI3K/Akt signaling pathway. In addition, cytosolic calcium (Ca) levels were measured by a fura-2 assay. The results demonstrated that miR-126 expression was upregulated in the ear tissues of rats with allergic contact dermatitis and IgE-activated MCs. The overexpression of miR-126 in RPMCs was established following miR-126 mimic transfection. The release of β-hexosaminidase and histamine, markers of MC degranulation, were significantly increased in cells with miR-126 overexpression. The phosphorylation of Akt was significantly increased following transfection with miR-126 mimics in stimulated cells, however the signaling activation was abrogated by LY294002. In addition, Ca influx was significantly promoted in stimulated RPMCs overexpressing miR-126. These results indicate that miR-126 accelerated IgE-mediated MC degranulation associated with the PI3K/Akt signaling pathway by promoting Ca influx. This suggests that miR-126 may be a promising therapeutic target for the treatment of allergic skin diseases.
据报道，肥大细胞（MCs）在包括哮喘、过敏性鼻炎和过敏反应在内的过敏性疾病中起关键作用。先前的一项研究表明，微小RNA-126（miR-126）与屋尘螨诱导的气道高反应性有关，但其分子机制尚不清楚。本研究旨在探讨miR-126对免疫球蛋白E（IgE）调节的MC脱颗粒的影响，并探索其潜在机制。使用大鼠模型和大鼠腹膜肥大细胞（RPMCs）对miR-126表达进行定量。通过转染miR-126模拟物或miR-126抑制剂来实现miR-126的过表达或下调，随后评估MC脱颗粒情况。通过蛋白质印迹分析检测miR-126对蛋白激酶B（Akt）和磷酸化Akt蛋白表达的影响。使用磷酸肌醇3-激酶（PI3K）抑制剂（LY294002）来确定PI3K/Akt信号通路的作用。此外，通过fura-2测定法测量胞质钙（Ca）水平。结果表明，在过敏性接触性皮炎大鼠的耳部组织和IgE激活的MCs中，miR-126表达上调。miR-126模拟物转染后，在RPMCs中实现了miR-126的过表达。在miR-126过表达的细胞中，MC脱颗粒标志物β-己糖胺酶和组胺的释放显著增加。在受刺激的细胞中，转染miR-126模拟物后Akt的磷酸化显著增加，然而LY294002消除了信号激活。此外，在过表达miR-126且受刺激的RPMCs中，Ca内流显著增加。这些结果表明，miR-126通过促进Ca内流加速了与PI3K/Akt信号通路相关的IgE介导的MC脱颗粒。这表明miR-126可能是治疗过敏性皮肤病的一个有前景的治疗靶点。
