The research focus of Professor Chao Jie from Southeast University Medical College is the research mechanism of pneumonia and pulmonary fibrosis. The team used Arr aystar CircRNA chip to find that circRNA circHECTD1 mediates SiO 2 -induced macrophage activation in silicosis via HECTD1/ZC3H12A-dependent ubiquitination, releasing related inflammatory factors and fibrotic factors, which in turn affects silicosis. The results suggest that circHECTD1/ZC3H12A/HECTD1 may be an effective intervention target for silicosis and fibrosis. The research results were published in the research group in the internationally renowned academic journal Theranostics ( influence factor 8.766 ) . (Chip experiment provided by Kang Cheng technical service) The results show: Significance High Pressure Extension Tubings High Pressure Extension Tubings,high pressure PVC extension tube,Extension Tubings,extension tube medical Anesthesia Medical Co., Ltd. , https://www.medicaldiverse.com
Research Background:
Silicosis is a systemic disease characterized by persistent chronic inflammation of the lung tissue, progressive pulmonary fibrosis, and systemic systemic inflammation caused by long-term inhalation of free silica (SiO 2 ) dust. Once the silicosis occurs, the lung injury develops progressively. Even if the dust exposure is stopped, the lung lesions progress, leading to pulmonary dysfunction, respiratory failure, and even death. Since little is known about the pathogenesis of silicosis, it has become an urgent problem to find molecular markers for early diagnosis of silicosis and targets for intervention in the process of pulmonary fibrosis.
CircRNAs are a class of non-coding RNAs with a closed loop structure that play a very important role in development, cellular function, and specific pathological responses such as cancer biology. CircRNA can competitively bind to miRNA as a microRNA sponge to regulate gene expression. It has become increasingly important to study circRNAs and their mechanisms involved in the development of disease and to provide targets for clinical diagnosis and treatment.
Research ideas:
This study focused on the study of cytokine activation and release of cytokines and chemotactic factors by SiO 2 inhalation, the processes involved in inflammatory response and pulmonary fibrosis, and its mechanisms. To investigate the role of circRNA in this process and mechanism, The researchers used the Arr aystar Mouse circRNA chip to study the differential expression profiles of circRNA in lung tissue of SiO 2 -induced mouse silicosis model and normal saline-treated normal mice, and screened 120 differentially expressed circRNAs (73 of them). circRNA up, down circRNA 47), preliminary laboratory studies combined, circHECTD1 differentially expressed host gene HECTD1 SiO 2 can participate in the inflammatory reaction induced silicosis and pulmonary fibrosis by ubiquitination, so as to focus on circ HECTD1.
qRT-PCR findings, circHECTD1 decreased dramatically in the SiO 2 induced pulmonary macrophages. circHECTD1 lentivirus study of cell viability and mobility after transfection macrophage cell line, was found after transfection, circHECTD1 can weaken SiO 2 induced activation of macrophages and the mobility increased, thus inferring circHECTD1 mediate SiO 2 macrophages induced Activation of cells. Subsequent RIP studies revealed that the transcription factor ZC3H12A can interact with circHECTD1 to mediate this activation process. By WB qRT-PCR studies and we found that the mRNA and protein levels of host genes HECTD1 circHECTD1 significantly increased the SiO 2 induced pulmonary macrophages, while circHECTD1 lentivirus macrophage cell line, mRNA levels were unaffected HECTD1 , but the expression was significantly inhibited, HECTD1 CRISPR activation suppressing plasmid digested plasmid NIC ACT and show, HECTD1 can influence the phenotypic change induced cell viability SiO 2 and macrophages, immune study also found that the precipitate, and may be ZC3H12A The HECTD1 interaction is involved in this process. The authors studied the mobilization of ACT and NIC macrophage cells into fibroblasts, and measured their mobility and cell viability. It was found that HECTD1 expression was up-regulated after SiO 2 induction, and fibroblast activation and migration were also affected. The above studies indicate that circHECTD1 is mediated by ZC3H12A-mediated ubiquitination, affecting the expression of downstream HECTD1, participating in the polar transformation of alveolar macrophages, releasing related inflammatory factors and fibrotic factors, and finally accelerating the fibrosis process. Finally, the authors determined the expression of HECTD1 in macrophages in bronchoalveolar lavage fluid of patients with clinical silicosis, and found that it was up-regulated and co-localized with macrophage marker F4/80. It is concluded that HECTD1 may be silicosis and fibrosis. Effective intervention targets.
Technical route: 
Figure 1: CircRNA microarray screening for differential expression of circRNA in mouse lung tissue for clustering, volcano mapping and scatter plot analysis 
Figure 2: CircHECTD1 down-regulates expression in SiO2-induced lung macrophages, and interacts with ZC3H12A to mediate SiO2-induced activation of lung macrophages 
Figure 3: HECTD1 upregulates expression in SiO2-induced lung macrophages, circHECTD1 can pass
HECTD1/ZC3H12A ubiquitination mediates SiO2-induced activation of pulmonary macrophages and promotes pulmonary fibrosis 
Figure 4: High expression of the circHECTD1 host gene HECTD1 in silicosis patients may be an effective intervention target for silicosis and fibrosis
In this study, Array star CircRNA microarray was used to study the mechanism of circRNA in SiO2-induced silicosis and pulmonary fibrosis. It was found that circHECTD1 can interact with ZC3H12A to mediate SiO2-induced macrophage activation. The study also found that circHECTD1 host gene HECTD1 can affect SiO2-induced macrophage activation and fibroblast activation and migration, while ZC3H12A can also The HECTD1 interaction is involved in this process. The above studies indicate that circHECTD1 is mediated by ZC3H12A-mediated ubiquitination, affecting the expression of downstream HECTD1, participating in the polar transformation of pulmonary macrophages, releasing related inflammatory factors and fibrotic factors, and accelerating the fibrosis process. Clinically, it was found that HECTD1 was up-regulated in macrophages in bronchoalveolar lavage fluid of patients with clinical silicosis, and co-localized with macrophage marker F4/80, indicating that HECTD1 can be used for clinical diagnosis and treatment of silicosis and fibrosis. Provide targets.
About the Author
Chao Jie : School of Medicine, Southeast University, professor, doctoral tutor, member of the editorial board of Scientific Reports, a journal of the Nature Publishing Group, a high-level talent of the “Six Talents Summit†in Jiangsu Province in 2015, Society of Toxicology (SOT) ) and members of the American Physiological Society (APS). His main research interests are basic research and clinical research on pulmonary inflammation and pulmonary fibrosis. The authors have published hundreds of SCI papers in Cell Death Dis, Front Behav NeurosciS, Cell Physiol Biochem, Theranostics, etc. More times.
Original source
circRNA Mediates Silica-Induced Macrophage Activation Via HECTD1/ZC3H12A-Dependent Ubiquitination. Theranostics. 2018.