School of Public Health, Xuzhou Medical University, Xuzhou 221004, China; Key Laboratory of Human Genetics and Environmental Medicine, Xuzhou Medical University, Xuzhou 221004, China.
School of Public Health, Xuzhou Medical University, Xuzhou 221004, China.
Toxicology. 2023 Jan 1;483:153384. doi: 10.1016/j.tox.2022.153384. Epub 2022 Nov 17.
Circular RNAs (circRNAs) are emerging as novel regulators in the biological development of various diseases, but their expression profiles, functions and mechanisms in silicosis and pulmonary fibrosis remain largely unexplored. In this study, we constructed a mouse model of pulmonary fibrosis by intratracheal injection of silica particles and then performed transcriptome RNA sequencing of lung tissues. The results showed that 78 circRNAs, 39 miRNAs and 262 mRNAs were differentially expressed. Among them, five circRNAs, three miRNAs and four mRNAs were further selected, and their abnormal expression was verified in mouse fibrotic lung tissues by RT-qPCR assay. The circRNA-associated ceRNA network including 206 ceRNA triplets was constructed based on abnormally expressed circRNAs, miRNAs and mRNAs, and miR-199b-5p, miR-296-5p and miR-708-5p were identified as hub miRNAs connected to circRNAs and mRNAs. Subsequently, GO and KEGG pathway enrichment analyses were performed to detect the potential roles of differentially expressed mRNAs in pulmonary fibrosis, which were mainly involved in immune response, Th17 cell differentiation, NF-κB signaling pathway and PI3K-Akt signaling pathway. Furthermore, we identified that hsa_circ_0006916 was up-regulated in pulmonary fibrosis. To characterize the potential role of hsa_circ_0006916, we transfected siRNA targeting hsa_circ_0006916 into alveolar macrophages and found that knockdown of hsa_circ_0006916 significantly increased the expression levels of M1 molecules IL-1β and TNF-α and reduced the expression level of M2 molecule TGF-β1, indicating that hsa_circ_0006916 may play an important role in the activation of M1-M2 polarization effect in macrophages. Our results provided important evidence on the possible contribution of these abnormal circRNAs to the development of silicosis and pulmonary fibrosis.
环状 RNA（circRNAs）作为各种疾病生物学发展中的新型调控因子而逐渐受到关注，但它们在矽肺和肺纤维化中的表达谱、功能和机制在很大程度上仍未被探索。在本研究中，我们通过气管内注射二氧化硅颗粒构建了一个肺纤维化小鼠模型，然后对肺组织进行了转录组 RNA 测序。结果显示，有 78 个 circRNAs、39 个 miRNAs 和 262 个 mRNAs 表达差异。其中，进一步选择了 5 个 circRNAs、3 个 miRNAs 和 4 个 mRNAs，并通过 RT-qPCR 实验验证了它们在小鼠纤维化肺组织中的异常表达。基于异常表达的 circRNAs、miRNAs 和 mRNAs，构建了包含 206 个 ceRNA 三联体的 circRNA 相关 ceRNA 网络，鉴定出 miR-199b-5p、miR-296-5p 和 miR-708-5p 作为与 circRNAs 和 mRNAs 相连的 hub miRNAs。随后，进行了 GO 和 KEGG 通路富集分析，以检测差异表达 mRNAs 在肺纤维化中的潜在作用，这些 mRNAs主要参与免疫反应、Th17 细胞分化、NF-κB 信号通路和 PI3K-Akt 信号通路。此外，我们发现 hsa_circ_0006916 在肺纤维化中上调。为了表征 hsa_circ_0006916 的潜在作用，我们将靶向 hsa_circ_0006916 的 siRNA 转染到肺泡巨噬细胞中，发现 hsa_circ_0006916 的敲低显著增加了 M1 分子 IL-1β 和 TNF-α 的表达水平，降低了 M2 分子 TGF-β1 的表达水平，表明 hsa_circ_0006916 可能在巨噬细胞中 M1-M2 极化效应的激活中发挥重要作用。我们的研究结果为这些异常 circRNAs 可能对矽肺和肺纤维化的发展的贡献提供了重要证据。
