Department of Pharmacology, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, PR China.
Functional Laboratory, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, PR China.
Int Immunopharmacol. 2018 May;58:87-93. doi: 10.1016/j.intimp.2018.03.016. Epub 2018 Mar 19.
Azithromycin is a potent agent that prevents airway remodeling. In this study, we hypothesized that azithromycin (35 mg/kg orally) alleviated airway remodeling through suppression of epithelial-to-mesenchymal transition (EMT) via downregulation of transforming growth factor-beta 1 (TGF-β1)/receptor for activated C-kinase1 (RACK1)/snail in mice. An ovalbumin (OVA)-induced Balb/c mice airway allergic inflammatory model was used. Airway inflammation and remodeling were evaluated with hematoxylin and eosin (HE), periodic acid-Schiff (PAS), and Masson staining. E-cadherin and N-cadherin (molecular markers of EMT) were analyzed by immunofluorescence, quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), and western blotting; α-smooth muscle actin (α-SMA) was evaluated using immunohistochemistry (IHC), qRT-PCR, and western blotting; and expression of TGF-β1/RACK1/Snail in lungs was measured by qRT-PCR and western blotting. Our data showed that azithromycin significantly reduced inflammation score, peribronchial smooth muscle layer thickness, goblet cell metaplasia, and deposition of collage fibers (P < 0.05), and effectively suppressed airway EMT (upregulated E-cadherin level, and downregulated N-cadherin and α-SMA levels) compared with the OVA group (P < 0.05). Moreover, the increasing mRNA and protein expressions of TGF-β1 and RACK1 and mRNA level of Snail in lung tissue were all significantly decreased in azithromycin-treated mice (P < 0.05). Taken together, our results suggest that azithromycin has the greatest effects on reducing airway remodeling by inhibiting TGF-β1/RACK1/Snail signal and improving the EMT in airway epithelium.
阿奇霉素是一种有效的药物，可预防气道重塑。在这项研究中，我们假设阿奇霉素（35mg/kg 口服）通过下调转化生长因子-β1（TGF-β1）/激活 C 激酶 1 受体（RACK1）/蜗牛，抑制上皮间质转化（EMT），从而减轻气道重塑在小鼠中。使用卵清蛋白（OVA）诱导的 Balb/c 小鼠气道过敏性炎症模型。通过苏木精和伊红（HE）、过碘酸希夫（PAS）和 Masson 染色评估气道炎症和重塑。通过免疫荧光、定量逆转录聚合酶链反应（qRT-PCR）和蛋白质印迹分析 E-钙黏蛋白和 N-钙黏蛋白（EMT 的分子标志物）；通过免疫组织化学（IHC）、qRT-PCR 和蛋白质印迹评估α-平滑肌肌动蛋白（α-SMA）；通过 qRT-PCR 和蛋白质印迹测量肺中 TGF-β1/RACK1/Snail 的表达。我们的数据表明，与 OVA 组相比，阿奇霉素可显著降低炎症评分、支气管平滑肌层厚度、杯状细胞化生和胶原纤维沉积（P<0.05），并有效抑制气道 EMT（上调 E-钙黏蛋白水平，下调 N-钙黏蛋白和α-SMA 水平）（P<0.05）。此外，在阿奇霉素治疗的小鼠中，肺组织中 TGF-β1 和 RACK1 的 mRNA 和蛋白质表达增加以及 Snail 的 mRNA 水平均显著降低（P<0.05）。综上所述，我们的研究结果表明，阿奇霉素通过抑制 TGF-β1/RACK1/Snail 信号通路和改善气道上皮细胞 EMT，对减轻气道重塑具有最大的作用。
