血管紧张素Ⅱ通过活性氧调控ACE和ACE2的表达

Angiotensin Ⅱ Regulates the Expression of ACE and ACE2 via Reactive Oxygen Species

目的研究血管紧张素II(Angiotensin II,Ang II)是否通过活性氧(Reactive oxygen species,ROS)调控人肾小管上皮细胞(Human kidney tubular epithelial cell line,HK-2)中血管紧张素转换酶(Angiotensin I converting enzyme,ACE)及血管紧张素转换酶2(Angiotensin I converting enzyme 2,ACE2)的表达。方法首先给予HK-2细胞不同浓度的Ang II刺激以检测ACE及ACE2表达的变化;然后给予细胞不同浓度的Ang II,在不同时间点,用2'7'-二氯双乙酸盐(2'7'-Dichlorofluorescin diacetate,DCFH)标记结合细胞内的ROS,流式细胞仪检测ROS水平;最后,我们给予细胞ROS抑制剂二苯基氯化碘(diphenyleneiodonium chloride,DPI),分别检测ROS、ACE及ACE2的表达。结果Ang II诱导肾小管上皮细胞内ACE表达上调,ACE2表达下调。另外,Ang II会引起细胞内ROS产生增多,且与刺激浓度和刺激时间相关。DPI能抑制Ang II诱导的ROS产生,并且抑制Ang II对ACE及ACE2的调控作用。结论 Ang II通过诱导人肾小管上皮细胞产生ROS从而调控ACE以及ACE2的表达。

Objective To study whether angiotensin Ⅱ regulates the expression of angiotensin I converting enzyme via ROS in human kidney tubular epithelial cells （HK-2）. Methods HK-2 cells were stimulated by different concentration of Ang Ⅱ to detect the expression of ACE and ACE2. Then the HK-2 cells were managed by Ang Ⅱ with different concentration and time and production of ROS were detected by flow cytometry. Finally HK-2 cells were pretreated by DPI, an inhibitor of ROS, 30 min before treatment orAng Ⅱ to detect the production of ROS, ACE and ACE2, respectively. Results Ang Ⅱ induces HK-2 cells to up-regulate the expression of ACE and down-regulate the expression of ACE2, meanwhile, it induces cells to produce more ROS at a dose and time dependent manner. DPI can inhibit the Ang Ⅱ-mediated regulation of ROS, ACE and ACE2. Conclusions These results indicate that angiotensin Ⅱ might regulate the expression of ACE and ACE2 in HK-2 cells via ROS.