Department of Traditional Chinese Medicine, Chang Gung Memorial Hospital at Taoyuan, Taoyuan 333008, Taiwan.
School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan 333323, Taiwan.
Int J Mol Sci. 2023 Oct 13;24(20):15130. doi: 10.3390/ijms242015130.
In this study, we confirmed that thrombin significantly increases the production of COX-2 and PGE in human tracheal smooth muscle cells (HTSMCs), leading to inflammation in the airways and lungs. These molecules are well-known contributors to various inflammatory diseases. Here, we investigated in detail the involved signaling pathways using specific inhibitors and small interfering RNAs (siRNAs). Our results demonstrated that inhibitors targeting proteins such as protein kinase C (PKC)δ, proline-rich tyrosine kinase 2 (Pyk2), c-Src, epidermal growth factor receptor (EGFR), phosphatidylinositol 3-kinase (PI3K), or activator protein-1 (AP-1) effectively reduced thrombin-induced COX-2 and PGE production. Additionally, transfection with siRNAs against PKCδ, Pyk2, c-Src, EGFR, protein kinase B (Akt), or c-Jun mitigated these responses. Furthermore, our observations revealed that thrombin stimulated the phosphorylation of key components of the signaling cascade, including PKCδ, Pyk2, c-Src, EGFR, Akt, and c-Jun. Thrombin activated COX-2 promoter activity through AP-1 activation, a process that was disrupted by a point-mutated AP-1 site within the COX-2 promoter. Finally, resveratrol (one of the most researched natural polyphenols) was found to effectively inhibit thrombin-induced COX-2 expression and PGE release in HTSMCs through blocking the activation of Pyk2, c-Src, EGFR, Akt, and c-Jun. In summary, our findings demonstrate that thrombin-induced COX-2 and PGE generation involves a PKCδ/Pyk2/c-Src/EGFR/PI3K/Akt-dependent AP-1 activation pathway. This study also suggests the potential use of resveratrol as an intervention for managing airway inflammation.
在这项研究中,我们证实凝血酶显著增加人气管平滑肌细胞(HTSMCs)中 COX-2 和 PGE 的产生,导致气道和肺部炎症。这些分子是各种炎症性疾病的已知贡献者。在这里,我们使用特定的抑制剂和小干扰 RNA(siRNA)详细研究了涉及的信号通路。我们的结果表明,针对蛋白激酶 C(PKC)δ、富含脯氨酸的酪氨酸激酶 2(Pyk2)、c-Src、表皮生长因子受体(EGFR)、磷脂酰肌醇 3-激酶(PI3K)或激活蛋白-1(AP-1)等蛋白的抑制剂有效地降低了凝血酶诱导的 COX-2 和 PGE 产生。此外,转染针对 PKCδ、Pyk2、c-Src、EGFR、蛋白激酶 B(Akt)或 c-Jun 的 siRNA 减轻了这些反应。此外,我们的观察结果表明,凝血酶刺激信号级联中的关键成分磷酸化,包括 PKCδ、Pyk2、c-Src、EGFR、Akt 和 c-Jun。凝血酶通过激活 AP-1 激活 COX-2 启动子活性,该过程被 COX-2 启动子内的点突变 AP-1 位点破坏。最后,发现白藜芦醇(研究最多的天然多酚之一)通过阻断 Pyk2、c-Src、EGFR、Akt 和 c-Jun 的激活,有效抑制 HTSMCs 中凝血酶诱导的 COX-2 表达和 PGE 释放。总之,我们的研究结果表明,凝血酶诱导的 COX-2 和 PGE 的产生涉及 PKCδ/Pyk2/c-Src/EGFR/PI3K/Akt 依赖性 AP-1 激活途径。这项研究还表明,白藜芦醇可能作为管理气道炎症的干预措施。