CAJ | 학술논문

背景：已有研究证实 microRNA-17-92簇在肺动脉高压中发挥着重要作用，精氨酸酶Ⅱ又参与低氧诱导的肺动脉平滑肌细胞的增殖，而人肺动脉平滑肌细胞中微小 RNA-17与精氨酸酶Ⅱ之间的相互作用尚未见研究报道。 　　目的：分析人肺动脉平滑肌细胞中，微小RNA-17与精氨酸酶Ⅱ的关系及其相互作用机制。 　　方法：选用4-8代的人肺动脉平滑肌细胞，分别给予转染微小RNA-17的抑制剂、增强剂、精氨酸酶Ⅱ小干扰RNA等处理，分别在常氧(体积分数21%O 2)及低氧(体积分数1%O 2)条件下培养。提取RNA和微小RNA，采用实时定量PCR法检测各组平滑肌细胞中微小RNA-17和精氨酸酶ⅡmRNA的表达，提取蛋白，采用Western blot法比较各组细胞中精氨酸酶Ⅱ等蛋白水平的表达。 　　结果与结论：低氧下人肺动脉平滑肌细胞中微小RNA-17及精氨酸酶Ⅱ的表达均明显增加，抑制微小RNA-17的表达可阻止低氧诱导的精氨酸酶Ⅱ的表达增加，微小 RNA-17的过表达可使精氨酸酶Ⅱ表达上调，精氨酸酶Ⅱ基因敲除后，低氧诱导的微小 RNA-17的表达受到抑制。提示人肺动脉平滑肌细胞中，精氨酸酶Ⅱ是微小RNA-17的一个新的靶基因，而且精氨酸酶Ⅱ可以反馈调节微小RNA-17的表达。
배경：이유연구증실 microRNA-17-92족재폐동맥고압중발휘착중요작용，정안산매Ⅱ우삼여저양유도적폐동맥평활기세포적증식，이인폐동맥평활기세포중미소 RNA-17여정안산매Ⅱ지간적상호작용상미견연구보도。 　　목적：분석인폐동맥평활기세포중，미소RNA-17여정안산매Ⅱ적관계급기상호작용궤제。 　　방법：선용4-8대적인폐동맥평활기세포，분별급여전염미소RNA-17적억제제、증강제、정안산매Ⅱ소간우RNA등처리，분별재상양(체적분수21%O 2)급저양(체적분수1%O 2)조건하배양。제취RNA화미소RNA，채용실시정량PCR법검측각조평활기세포중미소RNA-17화정안산매ⅡmRNA적표체，제취단백，채용Western blot법비교각조세포중정안산매Ⅱ등단백수평적표체。 　　결과여결론：저양하인폐동맥평활기세포중미소RNA-17급정안산매Ⅱ적표체균명현증가，억제미소RNA-17적표체가조지저양유도적정안산매Ⅱ적표체증가，미소 RNA-17적과표체가사정안산매Ⅱ표체상조，정안산매Ⅱ기인고제후，저양유도적미소 RNA-17적표체수도억제。제시인폐동맥평활기세포중，정안산매Ⅱ시미소RNA-17적일개신적파기인，이차정안산매Ⅱ가이반궤조절미소RNA-17적표체。
BACKGROUND:microRNA-17 is confirmed to play an important role in the development of pulmonary hypertension. Some research has shown that hypoxia-induced proliferation in human pulmonary artery smooth muscle celldepends on the induction of arginase II. There is no report about whether there is some interaction between microRNA-17 and arginase II in human pulmonary artery smooth muscle cells. OBJECTIVE:To investigate the possible interactions between microRNA-17 and arginase II in hypoxic human pulmonary artery smooth muscle cells. METHODS:Passage 4 human pulmonary artery smooth muscle cells were cultured in 21%O 2 and 5%CO 2 (normoxia) or 1%O 2 and 5%CO 2 (hypoxia), and then transfected with mimic or inhibitor of microRNA-17 or arginase II-smal interfering RNA. RNA, microRNA and protein were isolated separately. Expression of microRNA-17 and arginase II was detected with real-time quantitative PCR and western blot assay. RESULTS AND CONCLUSION:The level of microRNA-17 was significantly increased in cultured human pulmonary artery smooth muscle cells exposed to 1%O 2 hypoxia, as was arginase II mRNA and protein expression. Furthermore, inhibition of microRNA-17 expression decreased the mRNA and protein levels of arginase II in the human pulmonary artery smooth muscle cells under hypoxia. Conversely, over-expression of microRNA-17 increased the mRNA and protein levels of arginase II in the human pulmonary artery smooth muscle cells under normoxia and hypoxia. Knockdown of arginase II by siRNA abolished the hypoxia-induced up-regulation of microRNA-17 expression. These findings indicate that arginase II is a target gene of microRNA-17 and can regulate the expression of microRNA-17 in human pulmonary artery smooth muscle cells.