Shen Wenbo, Jia Wei, Wu Qiang, Shen Li, Wang Yisheng
Shanghai TCM-Integrated Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.
Respiratory Department, Shanghai TCM-Integrated Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200082, China.
Immunobiology. 2025 Jul 16;230(4):153103. doi: 10.1016/j.imbio.2025.153103.
Baicalin, a natural compound isolated from the root of Scutellaria baicalensis Georgi, has been shown to have various pharmacological effects on lung diseases including asthma. Recently, research has suggested that baicalin combined with exosomes may have significant potential against disease development. The present work analyzes the effects of exosomes derived from baicalin-pretreated bone marrow mesenchymal stem cells (BMSCs) on asthma and the underlying mechanism.
BALB/c mice were sensitized with ovalbumin (OVA) through intraperitoneal injection to establish an animal model of asthma. Human bronchial epithelial cells (16HBE) were exposed to lipopolysaccharide to mimic a cell model of asthma. The pathological conditions of lung tissues in OVA-induced mice were analyzed by haematoxylin and eosin staining assays. Masson staining and quantification analysis were conducted to analyze percentage of collagen fibers in lung tissues of OVA-induced mice. The Wright-Giemsa assay was used to determine the number of eosinophils, neutrophils, lymphocytes and macrophages. Enzyme-linked immunosorbent assays were performed to analyze expression levels of inflammatory factors including IL-4, IL-5, IL-13 and TNF-α levels. The values of airway resistance (Rrs), elastance (Ers) and compliance (Crs) were recorded for analyzing airway hyperresponsiveness through the FlexiVent system. Protein expression was analyzed by immunohistochemistry (IHC) and/or western blotting assay.
Ovalbumin (OVA) pretreatment increased airway inflammation, airway hyperresponsiveness, collagen deposition and epithelial-mesenchymal transition (EMT) in mice, however, these phenomena were significantly improved after treatment with baicalin-pretreated BMSC exosomes. Lipopolysaccharide (LPS)-induced 16HBE cells showed increased levels of interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin-13 (IL-13) and tumor necrosis factor-α (TNF-α), elevated N-cadherin and Vimentin protein expression, and decreased E-cadherin protein expression, whereas these LPS-induced effects were relieved after treatment with baicalin-pretreated BMSC exosomes. Additionally, protein expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response protein 88 (MyD88) and phosphor p65 (p-p65) was upregulated in lung tissues of OVA-induced mice and LPS-stimulated 16HBE cells, but these phenomena were counteracted following exosomes treatment from baicalin-pretreated BMSCs.
Exosomes derived from baicalin-pretreated BMSCs ameliorated airway inflammation, airway hyperresponsiveness and airway remodeling after asthma by inactivating the TLR4/MyD88/nuclear factor kappa B pathway, providing a therapeutic strategy for asthma.
黄芩苷是从黄芩根中分离出的一种天然化合物，已被证明对包括哮喘在内的肺部疾病具有多种药理作用。最近，研究表明黄芩苷与外泌体联合使用可能对疾病发展具有显著潜力。本研究分析了黄芩苷预处理的骨髓间充质干细胞（BMSC）来源的外泌体对哮喘的影响及其潜在机制。
通过腹腔注射用卵清蛋白（OVA）致敏BALB/c小鼠，建立哮喘动物模型。将人支气管上皮细胞（16HBE）暴露于脂多糖以模拟哮喘细胞模型。通过苏木精和伊红染色分析OVA诱导的小鼠肺组织的病理状况。进行Masson染色和定量分析以分析OVA诱导的小鼠肺组织中胶原纤维的百分比。采用瑞氏-吉姆萨染色法测定嗜酸性粒细胞、中性粒细胞、淋巴细胞和巨噬细胞的数量。进行酶联免疫吸附测定以分析包括IL-4、IL-5、IL-13和TNF-α水平在内的炎症因子的表达水平。记录气道阻力（Rrs）、弹性（Ers）和顺应性（Crs）值，通过FlexiVent系统分析气道高反应性。通过免疫组织化学（IHC）和/或蛋白质印迹分析蛋白质表达。
卵清蛋白（OVA）预处理增加了小鼠的气道炎症、气道高反应性、胶原沉积和上皮-间质转化（EMT），然而，用黄芩苷预处理的BMSC外泌体治疗后，这些现象得到显著改善。脂多糖（LPS）诱导的16HBE细胞显示白细胞介素-4（IL-4）、白细胞介素-5（IL-5）、白细胞介素-13（IL-13）和肿瘤坏死因子-α（TNF-α）水平升高，N-钙黏蛋白和波形蛋白蛋白表达升高，E-钙黏蛋白蛋白表达降低，而用黄芩苷预处理的BMSC外泌体治疗后，这些LPS诱导的效应得到缓解。此外，OVA诱导的小鼠肺组织和LPS刺激的16HBE细胞中，Toll样受体4（TLR4）、髓样分化初级反应蛋白88（MyD88）和磷酸化p65（p-p65）的蛋白表达上调，但用黄芩苷预处理的BMSCs来源的外泌体处理后，这些现象得到抵消。
黄芩苷预处理的BMSCs来源外泌体通过使TLR4/MyD88/核因子κB通路失活，改善哮喘后的气道炎症、气道高反应性和气道重塑，为哮喘提供了一种治疗策略。
