Department of Respiratory and Critical Care Medicine, Research Laboratory of the Respiratory System Diseases, First Affiliated Hospital, Fujian Medical University, Fuzhou, China.
Department of Pathology, First Affiliated Hospital, Fujian Medical University, Fuzhou, China.
J Interferon Cytokine Res. 2020 Aug;40(8):377-388. doi: 10.1089/jir.2019.0184. Epub 2020 Aug 3.
This study explored the triggering mechanism of interstitial lung disease (ILD). We established the effects of immunogenic and neurogenic calcitonin gene-related peptide (CGRP) imbalance on the regulation of aquaporin 5 (AQP5) expression and the repair responses that promote the transition from alveolar epithelial cell (AEC) apoptosis to pulmonary fibrosis. Newly diagnosed ILD patients ( = 60) were enrolled, whose serological levels of β-CGRP, α-CGRP, AQP5, receptor activity modifying protein 1, and receptor component protein were detected by ELISA. Th1 and Th2 cytokines and CD4 and CD8 cells were measured by flow cytometry method. , bleomycin (BLM) was set for modeling pulmonary fibrosis. A -HET model was set as a chronic pulmonary fibrosis model. Hematoxylin-eosin, immunohistochemistry, and Masson's trichrome staining were performed to assess the role of apoptosis in the injured lung. The concentrations of cytokines were determined by cytokine antibody arrays. Abnormal activation of serological CD4 T lymphocytes and predominant Th2 response was established in the patients with ILD. Moreover, the ratio of β-CGRP/α-CGRP positively correlated with the increased level of AQP5 in patients with ILD. , a significant increase of AQP5 and β-CGRP at the chronic stage of pulmonary fibrosis was induced by BLM in the mice model, whereas the expression of AQP5 protein was generally lower in the acute alveolitis phase. Moreover, the levels of AQP5 and α-CGRP in the -HET rats were lower than those of the normal saline group. The high ratio β-CGRP/α-CGRP enhanced the expression of AQP5, inhibited transforming growth factor-β1 (TGFβ1)/P-Smad1/Smad4 pathway, and upregulated the NRF2 signal, whereas the apoptosis of AECs was significantly reduced in late-stage pulmonary fibrosis. The imbalance of β-CGRP/α-CGRP may be associated with the predominance of Th2 response and participate in the process of AEC apoptosis in lung fibrosis. The high ratio of β-CGRP/α-CGRP may elevate the level of AQP5 through inactivation of the TGF-β1/smad1 signaling pathway and upregulation of the Nrf2 signaling in the chronic stage of pulmonary fibrosis.
本研究探讨了间质性肺病（ILD）的触发机制。我们建立了免疫原性和神经源性降钙素基因相关肽（CGRP）失衡对水通道蛋白 5（AQP5）表达调节和修复反应的影响，促进了肺泡上皮细胞（AEC）凋亡向肺纤维化的转变。纳入了新诊断的ILD 患者（n=60），通过 ELISA 检测了其血清 β-CGRP、α-CGRP、AQP5、受体活性修饰蛋白 1 和受体成分蛋白的水平。通过流式细胞术方法测量了 Th1 和 Th2 细胞因子以及 CD4 和 CD8 细胞。建立博来霉素（BLM）模型用于肺纤维化建模。建立 A-HET 模型作为慢性肺纤维化模型。进行苏木精-伊红、免疫组织化学和 Masson 三色染色以评估凋亡在受损肺中的作用。通过细胞因子抗体阵列测定细胞因子浓度。ILD 患者存在血清 CD4 T 淋巴细胞异常激活和以 Th2 反应为主导的情况。此外，ILD 患者血清中β-CGRP/α-CGRP 的比值与 AQP5 水平的升高呈正相关。在 BLM 诱导的小鼠模型中，肺纤维化慢性期 AQP5 和β-CGRP 显著增加，而在急性肺泡炎期 AQP5 蛋白表达通常较低。此外，-HET 大鼠的 AQP5 和α-CGRP 水平低于生理盐水组。高β-CGRP/α-CGRP 比值增强了 AQP5 的表达，抑制了转化生长因子-β1（TGFβ1）/P-Smad1/Smad4 途径，上调了 NRF2 信号，而晚期肺纤维化中 AEC 的凋亡明显减少。β-CGRP/α-CGRP 的失衡可能与 Th2 反应的优势有关，并参与肺纤维化中 AEC 凋亡的过程。高β-CGRP/α-CGRP 比值可能通过 TGF-β1/smad1 信号通路的失活和慢性肺纤维化中 Nrf2 信号的上调来提高 AQP5 的水平。
