- 作者: Yu-Tung Hsieh, Yu-Chi Chou, Pin-Yu Kuo, Hung-Wen Tsai, Yi-Ting Yen, Ai-Li Shiau & Chrong-Reen Wang
- 作者服務機構: 1.Biomedical Translation Research Center, Academia Sinica, Taipei, Taiwan 2.Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan 3.Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan 4.Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan 5.Departments of Pathology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan 6.Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- 中文摘要:
- 英文摘要:
Background
Increasing evidences have suggested an important role of microRNAs (miRNAs) in regulating cell death processes including NETosis and apoptosis. Dysregulated expression of miRNAs and increased formation of neutrophil extracellular traps (NETs) and apoptosis participate in autoimmune-mediated diffuse alveolar hemorrhage (DAH), mostly associated with pulmonary capillaritis in systemic lupus erythematosus (SLE) patients. In particular, besides the inhibition of apoptosis, miR-146a can control innate and acquired immune responses, and regulate the toll-like receptor pathway through targeting TRAF6 to reduce the expression of pro-inflammatory cytokines/chemokines like IL-8, a NETosis inducer.
Methods
Expression of miR-146a, TRAF6 and NETs were examined in peripheral blood neutrophils (PBNs) and lung tissues from SLE-associated DAH patients, and in neutrophils and pristane-induced DAH lung tissues from C57BL/6 mice. To assess NETs formation, we examined NETosis-related DNAs morphology and crucial mediators including protein arginine deiminase 4 and citrullinated Histone 3. Expression of miR-146a and its endogenous RNA SNHG16 were studied in HL-60 promyelocytic cells and MLE-12 alveolar cells during NETosis and apoptosis processes, respectively. MiR-146a-overexpressed and CRISPR-Cas13d-mediated SNHG16-silenced HL-60 cells were investigated for NETosis. MiR-146a-overexpressed MLE-12 cells were analyzed for apoptosis. Pristane-injected mice received intra-pulmonary miR-146a delivery to evaluate therapeutic efficacy in DAH.
Results
In DAH patients, there were down-regulated miR-146a levels with increased TRAF6 expression and PMA/LPS-induced NETosis in PBNs, and down-regulated miR-146a levels with increased TRAF6, high-mobility group box 1 (HMGB1), IL-8, NETs and apoptosis expression in lung tissues. HMGB1-stimulated mouse neutrophils had down-regulated miR-146a levels with increased TRAF6, IL-8 and NETs expression. PMA-stimulated HL-60 cells had down-regulated miR-146a levels with enhanced NETosis. MiR-146a-overexpressed or SNHG16-silenced HL-60 cells showed reduced NETosis. Apoptotic MLE-12 cells had down-regulated miR-146a expression and increased HMGB1 release, while miR-146a-overexpressed MLE-12 cells showed reduced apoptosis and HMGB1 production. There were down-regulated miR-146a levels with increased TRAF6, HMGB1, IL-8, NETs and apoptosis expression in mouse DAH lung tissues. Intra-pulmonary miR-146a delivery could suppress DAH by reducing TRAF6, IL-8, NETs and apoptosis expression.
Conclusions
Our results demonstrate firstly down-regulated pulmonary miR-146a levels with increased TRAF6 and IL-8 expression and NETs and apoptosis formation in autoimmune-mediated DAH, and implicate a therapeutic potential of intra-pulmonary miR-146a delivery. - 中文關鍵字:
- 英文關鍵字: Difuse alveolar hemorrhage, MiR-146a, TRAF6, Neutrophil extracellular trap, NETosis, Apoptosis, IL-8, HMGB1, Systemic lupus erythematosus. intra-pulmonary delivery