Department of Emergency Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
Int Arch Allergy Immunol. 2022;183(9):919-930. doi: 10.1159/000524718. Epub 2022 Jun 3.
Asthma is a common inflammatory respiratory disease with increasing incidence worldwide. This study aimed to investigate the mechanism of miR-146a-5p in reducing allergic airway inflammation by inhibiting NLRP3 inflammasome activation in macrophages.
Allergic mouse models were established by ovalbumin stimulation, and mice were treated with miR-146a-5p agomir and oe-TIRAP 3 h before OVA stimulation. The pathological changes of lung tissues were observed by hematoxylin-eosin staining. The airway hyperresponsiveness of mice were examined. The miR-146a-5p level was detected by RT-qPCR. The inflammatory cytokines (IL-18/TNF-α) and anti-inflammatory cytokine IL-10 levels in bronchoalveolar lavage fluid and serum IgE levels were examined by ELISA. Airway inflammation in mice was detected after miR-146a-5p overexpression. The levels of NLRP3/ASC/caspase1 proteins and macrophage M1/M2 surface markers in mouse lung tissues were examined using immunohistochemistry, Western blot, and flow cytometry. The targeting relationship between miR-146a-5p and TIRAP was verified by dual-luciferase assay. The p65 levels in the cytoplasm/nucleus of mouse lung tissue were measured.
miR-146a-5p was downregulated in the lung tissues of allergic mice, and miR-146a-5p overexpression alleviated airway inflammation in asthmatic mice. miR-146a-5p suppressed NLRP3 inflammasome activation in macrophages of allergic mice, reduced NLRP3/ASC/caspase1 protein levels in lung tissues, blocked M1 polarization, and promoted M2 polarization. miR-146a-5p targeted TIRAP. TIRAP overexpression partially reversed the promoting effect of miR-146a-5p on M2 polarization. miR-146a-5p can inhibit the activation of the TIRAP/NF-κB pathway.
miR-146a-5p inhibited NLRP3 inflammasome activation in macrophages in the lung tissue of allergic mice, prevented pro-inflammatory phenotype M1 polarization, and promoted anti-inflammatory phenotype M2 polarization by targeting the TIRAP/NF-κB pathway, thus alleviating airway inflammation in allergic asthma.
哮喘是一种常见的炎症性呼吸系统疾病，其全球发病率呈上升趋势。本研究旨在通过抑制巨噬细胞中 NLRP3 炎性小体的激活来探讨 miR-146a-5p 减少过敏性气道炎症的机制。
通过卵清蛋白刺激建立过敏性小鼠模型，在 OVA 刺激前用 miR-146a-5p 激动剂和 oe-TIRAP 处理小鼠。通过苏木精-伊红染色观察肺组织的病理变化。检测小鼠气道高反应性。通过 RT-qPCR 检测 miR-146a-5p 水平。通过 ELISA 检测支气管肺泡灌洗液和血清中炎症细胞因子（IL-18/TNF-α）和抗炎细胞因子 IL-10 水平。通过过表达 miR-146a-5p 检测小鼠气道炎症。通过免疫组织化学、Western blot 和流式细胞术检测小鼠肺组织中 NLRP3/ASC/caspase1 蛋白水平和巨噬细胞 M1/M2 表面标志物。通过双荧光素酶报告基因实验验证 miR-146a-5p 与 TIRAP 的靶向关系。测量小鼠肺组织中细胞质/核内的 p65 水平。
过敏性小鼠肺组织中 miR-146a-5p 下调，过表达 miR-146a-5p 可减轻哮喘小鼠气道炎症。miR-146a-5p 抑制过敏性小鼠巨噬细胞中 NLRP3 炎性小体的激活，降低肺组织中 NLRP3/ASC/caspase1 蛋白水平，阻断 M1 极化，促进 M2 极化。miR-146a-5p 靶向 TIRAP。TIRAP 过表达部分逆转了 miR-146a-5p 对 M2 极化的促进作用。miR-146a-5p 可抑制 TIRAP/NF-κB 通路的激活。
miR-146a-5p 通过靶向 TIRAP/NF-κB 通路抑制过敏性小鼠肺组织中巨噬细胞 NLRP3 炎性小体的激活，防止促炎表型 M1 极化，促进抗炎表型 M2 极化，从而减轻过敏性哮喘的气道炎症。
