Department of Pediatrics, Second Affiliated Hospital of Harbin Medical University, China; Department of Emergency, Sixth Affiliated Hospital of Harbin Medical University（Jiangnan Courtyard), China.
Department of Pediatrics, Second Affiliated Hospital of Harbin Medical University, China.
Mol Immunol. 2024 Apr;168:38-46. doi: 10.1016/j.molimm.2024.02.013. Epub 2024 Feb 28.
Asthma, a common pediatric pulmonary disease, significantly affects children's healthy development. This study aimed to investigate the functions of human β defensin-3 (HBD-3) in asthma progression. For this purpose, blood samples from asthmatic and healthy children were collected. Moreover, the airway smooth muscle cells (ASMCs) were treated with platelet-derived growth factor BB (PDGF-BB) to develop an in vitro asthma model, then evaluated cell viability and migration via CCK-8 and transwell assays. The mRNA levels of interferon γ (INF-γ), interleukin 4 (IL-4), interleukin 10 (IL-10), alpha-smooth muscle actin (α-SMA), HBD-3, and the protein levels of phosphatidylinositol 3-kinase (PI3K) along with protein kinase B (AKT) were detected. Similarly, the N6-methyladenosine (m6A) content in the ASMCs and m6A levels of HBD-3 were also measured. Results indicated an upregulated HBD-3 in the asthmatic children. The ASMCs were found to be stimulated by PDGF-BB, in addition to the promotion of cell viability and migration. The INF-γ, IL-4, and α-SMA levels were reduced, while IL-10 was elevated in PDGF-BB-stimulated ASMCs. Silencing HBD-3 in PDGF-BB stimulated ASMCs was found to exert the opposite effect by inhibiting cell viability and migration, enhancing the levels of INF-γ, IL-4, and α-SMA, while the IL-10 levels were found to decline. PDGF-BB stimulation of ASMCs resulted in activation of the PI3K/AKT signaling pathway, which was blocked post HBD-3 silencing, while the role of si-hBD in PDGF-BB stimulated ASMCs was neutralized post-treatment with IGF-1. Finally, it was found that METTL3 overexpression prominently upregulated the m6A levels of HBD-3 and decreased the mRNA expression and stability of HBD-3 in the PDGF-BB-stimulated ASMCs. The study concluded that METTL3-mediated HBD-3 participates in the progression of asthma through the PI3K/AKT signaling pathway.
哮喘是一种常见的儿科肺部疾病，严重影响儿童的健康发育。本研究旨在探讨人β防御素-3（HBD-3）在哮喘进展中的作用。为此，收集了哮喘患儿和健康儿童的血液样本。此外，用血小板衍生生长因子 BB（PDGF-BB）处理气道平滑肌细胞（ASMCs），建立体外哮喘模型，然后通过 CCK-8 和 Transwell 实验评估细胞活力和迁移。检测干扰素 γ（INF-γ）、白细胞介素 4（IL-4）、白细胞介素 10（IL-10）、α-平滑肌肌动蛋白（α-SMA）、HBD-3 的 mRNA 水平以及磷酸肌醇 3-激酶（PI3K）和蛋白激酶 B（AKT）的蛋白水平。同样，检测了 ASMCs 中的 N6-甲基腺苷（m6A）含量和 HBD-3 的 m6A 水平。结果表明，哮喘患儿的 HBD-3 水平上调。发现 PDGF-BB 刺激 ASMCs 后，细胞活力和迁移均得到促进。PDGF-BB 刺激的 ASMCs 中 INF-γ、IL-4 和 α-SMA 水平降低，而 IL-10 水平升高。在 PDGF-BB 刺激的 ASMCs 中沉默 HBD-3 发现可通过抑制细胞活力和迁移发挥相反的作用，同时增加 INF-γ、IL-4 和 α-SMA 水平，而 IL-10 水平下降。PDGF-BB 刺激 ASMCs 导致 PI3K/AKT 信号通路激活，沉默 HBD-3 后被阻断，而 IGF-1 处理后 si-hBD 在 PDGF-BB 刺激的 ASMCs 中的作用被中和。最后发现，METTL3 过表达显著上调 PDGF-BB 刺激的 ASMCs 中 HBD-3 的 m6A 水平，并降低 HBD-3 的 mRNA 表达和稳定性。研究结论是，METTL3 介导的 HBD-3 通过 PI3K/AKT 信号通路参与哮喘的进展。
