MiR-124-3p通过靶向NFIB调节鹦鹉热衣原体诱导的HBE细胞氧化应激

MiR-124-3p regulates Chlamydia psittaci-induced oxidative stress in HBE cells by targeting NFIB

摘要:

背景 鹦鹉热衣原体(Chlamydia psittaci, Cps)是一种具有宿主多样性的人兽共患病病原体，引起鹦鹉热等局部或全身性疾病。宿主氧化应激反应与衣原体感染过程密切相关。目的 探究Cps感染对人支气管上皮(human bronchial epithelial, HBE)细胞氧化应激的影响，以及miR-124-3p和核因子I-B (nuclear factor I-B, NFIB)在其中的调控作用。方法 以感染复数(multiplicity of infection, MOI)为3的Cps感染HBE细胞，分别检测活性氧(reactive oxygen species, ROS)、超氧化物歧化酶(superoxide dismutase, SOD)、丙二醛(malondialdehyde, MDA)含量变化，以及miR-124-3p和NFIB的表达水平，评估Cps感染后对HBE细胞氧化应激及对miR-124-3p和NFIB表达水平的影响。在体外试验中，分别转染miR-124-3p mimic、miR-124-3p inhibitor，或共转染si-NFIB与miR-124-3p inhibitor，分析miR-124-3p和NFIB的表达变化，以探讨miR-124-3p和NFIB之间的相关性。同时，通过检测ROS、MDA和SOD水平，进一步分析miR-124-3p和NFIB对Cps感染诱导的氧化应激的调控作用。结果 经MOI为3的Cps感染后，HBE细胞的ROS、MDA水平升高，SOD活力下降；miR-124-3p表达上调，NFIB表达下调。转染miR-124-3p mimic后，NFIB的mRNA和蛋白表达水平下降，促进细胞氧化应激反应；而转染miR-124-3p inhibitor后，NFIB的表达水平升高，氧化应激反应受到抑制。相较于单独转染miR-124-3p inhibitor组，在Cps感染的HBE细胞中共转染si-NFIB和miR-124-3p inhibitor后细胞内ROS水平和MDA含量显著升高，而SOD活性明显降低。结论 miR-124-3p通过靶向NFIB调控Cps感染诱导的HBE细胞氧化应激。

Abstract:

Background Chlamydia psittaci is a zoonotic pathogen with diverse hosts, causing local or systemic diseases such as psittacosis. The oxidative stress of hosts is closely related to the Chlamydia infection process.Objective To explore the impact of C. psittaci infection on oxidative stress in HBE cells and the roles of miR-124-3p and nuclear factor I-B (NFIB) in this process.Methods HBE cells were infected with C. psittaci at a multiplicity of infection of 3. The levels of reactive oxygen species (ROS), superoxide dismutase (SOD), and malondialdehyde (MDA) and the expression levels of miR-124-3p and NFIB were measured to evaluate the impacts of C. psittaci infection on the oxidative stress and the expression levels of miR-124-3p and NFIB. After transfection with miR-124-3p inhibitor or miR-124-3p mimic or co-transfection with si-NFIB and miR-124-3p inhibitor, the levels of miR-124-3p and NFIB were measured to evaluate their correlation, and the levels of ROS, MDA, and SOD were determined to evaluate the impacts of miR-124-3p and NFIB on the oxidative stress induced by C. psittaci infection.Results The C. psittaci-infected HBE cells showed elevated levels of ROS and MDA, a weakened activity of SOD, an up-regulated expression level of miR-124-3p, and a down-regulated expression level of NFIB. After transfection with miR-124-3p mimic, the mRNA and protein levels of NFIB were down-regulated, and the oxidative stress caused by C. psittaci infection was enhanced, whereas miR-124-3p inhibitor produced opposite effects. In C. psittaci-infected HBE cells, the co-transfection with si-NFIB and miR-124-3p inhibitor elevated the levels of ROS and MDA and decreased the activity of SOD compared with transfection with only miR-124-3p inhibitor.Conclusion MiR-124-3p regulates oxidative stress in C. psittaci- infected HBE cells by targeting NFIB.