Academy of Chinese Medical Sciences, Henan University of Chinese Medicine, Zhengzhou, China.
Microbiology and Immunology, and Department of Otolaryngology, New York Medical College, New York, NY, United States.
Front Immunol. 2021 Nov 5;12:736479. doi: 10.3389/fimmu.2021.736479. eCollection 2021.
Airway remodeling is associated with dysregulation of epithelial-mesenchymal transition (EMT) in patients with asthma. Sinomenine (Sin) is an effective, biologically active alkaloid that has been reported to suppress airway remodeling in mice with asthma. However, the molecular mechanisms behind this effect remain unclear. We aimed to explore the potential relationship between Sin and EMT in respiratory epithelial cells and . First, 16HBE cells were exposed to 100 μg/mL LPS and treated with 200 μg/mL Sin. Cell proliferation, migration, and wound healing assays were performed to evaluate EMT, and EMT-related markers were detected using Western blotting. Mice with OVA-induced asthma were administered 35 mg/kg or 75 mg/kg Sin. Airway inflammation and remodeling detection experiments were performed, and EMT-related factors and proteins in the TGF-β1 pathway were detected using IHC and Western blotting. We found that Sin suppressed cell migration but not proliferation in LPS-exposed 16HBE cells. Sin also inhibited MMP7, MMP9, and vimentin expression in 16HBE cells and respiratory epithelial cells from mice with asthma. Furthermore, it decreased OVA-specific IgE and IL-4 levels in serum, relieved airway remodeling, attenuated subepithelial collagen deposition, and downregulating TGF-β1and Smad3 expression in mice with asthma. Our results suggest that Sin suppresses EMT by inhibiting IL-4 and downregulating TGF-β1 and Smad3 expression.
气道重塑与哮喘患者上皮-间充质转化（EMT）的失调有关。青藤碱（Sin）是一种有效的生物活性生物碱，据报道可抑制哮喘小鼠的气道重塑。然而，其作用的分子机制尚不清楚。我们旨在探讨 Sin 与呼吸上皮细胞 EMT 之间的潜在关系。首先，将 16HBE 细胞暴露于 100μg/ml LPS 并以 200μg/ml Sin 处理。通过细胞增殖、迁移和伤口愈合实验评估 EMT，并用 Western blot 检测 EMT 相关标志物。用 OVA 诱导的哮喘小鼠给予 35mg/kg 或 75mg/kg Sin。进行气道炎症和重塑检测实验，并用 IHC 和 Western blot 检测 TGF-β1 通路中的 EMT 相关因子和蛋白。我们发现 Sin 抑制 LPS 暴露的 16HBE 细胞迁移但不抑制增殖。Sin 还抑制 16HBE 细胞和哮喘小鼠呼吸上皮细胞中 MMP7、MMP9 和波形蛋白的表达。此外，它降低了哮喘小鼠血清中的 OVA 特异性 IgE 和 IL-4 水平，缓解了气道重塑，减轻了上皮下胶原沉积，并下调了哮喘小鼠中 TGF-β1 和 Smad3 的表达。我们的结果表明，Sin 通过抑制 IL-4 和下调 TGF-β1 和 Smad3 的表达来抑制 EMT。
