Hypoxic regulation of angiotensin-converting enzyme 2 and Mas receptor in human CD34+ cells
Hypoxic regulation of angiotensin-converting enzyme 2 and Mas receptor in human CD34+ cells
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DOI：
10.1002/jcp.28643
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发表时间：
2019-11-01
影响因子：
5.6
通讯作者：
Jarajapu, Yagna P. R.
中科院分区：
文献类型：
--
作者：
Joshi, Shrinidh;Wollenzien, Hannah;Jarajapu, Yagna P. R.
CD 34（+）造血干/祖细胞（HSPCs）是血管生成细胞，缺氧是这些细胞血管修复功能的强刺激。血管紧张素转换酶2（ACE 2）/血管紧张素-（1-7）/Mas受体（MasR）途径可刺激CD 34（+）细胞的血管保护功能。本研究检测了ACE 2和MasR是否参与了CD 34（+）细胞的缺氧刺激。从来自健康受试者（n=46）的循环单核细胞中分离细胞，并将其暴露于常氧（20%O-2）或缺氧（1%O-2）。荧光素酶报告基因测定在用慢病毒转导的细胞中进行，所述慢病毒携带ACE 2-或MasR-或具有萤火虫荧光素酶报告基因的scramble-3 '-非翻译区基因。测定ACE、血管紧张素受体1型（AT 1 R）、ACE 2和MasR的表达或活性。在源自经历后肢缺血（HLI）的小鼠的HSPC中验证了体外观察。与常氧相比，在基础条件下或对血管内皮生长因子（VEGF）或基质衍生因子1 α（SDF）的反应中，体外暴露于低氧可增加CD 34（+）细胞的增殖和迁移。ACE 2或MasR的表达相对于常氧增加，而ACE或AT 1 R的表达不变。相对于对照，在用编码ACE 2-或MasR启动子的荧光素酶报告质粒转染的细胞中，缺氧增加荧光素酶活性。在常氧条件下，用VEGF或SDF模拟缺氧作用。缺氧诱导的功能性ACE 2片段的ADAM 17依赖性脱落。在经历HLI的小鼠中，在循环HSPC中观察到ACE 2和MasR的表达/活性增加。这项研究为缺氧上调CD 34（+）细胞中的ACE 2和MasR提供了令人信服的证据，这可能有助于血管修复。
CD34(+) hematopoietic stem/progenitor cells (HSPCs) are vasculogenic and hypoxia is a strong stimulus for the vasoreparative functions of these cells. Angiotensin-converting enzyme 2 (ACE2)/angiotensin-(1-7)/Mas receptor (MasR) pathway stimulates vasoprotective functions of CD34(+) cells. This study tested if ACE2 and MasR are involved in the hypoxic stimulation of CD34(+) cells. Cells were isolated from circulating mononuclear cells derived from healthy subjects (n=46) and were exposed to normoxia (20% O-2) or hypoxia (1% O-2). Luciferase reporter assays were carried out in cells transduced with lentivirus carrying ACE2- or MasR- or a scramble-3 '-untranslated region gene with a firefly luciferase reporter. Expressions or activities of ACE, angiotensin receptor Type 1 (AT1R), ACE2, and MasR were determined. In vitro observations were verified in HSPCs derived from mice undergoing hindlimb ischemia (HLI). In vitro exposure to hypoxia-increased proliferation and migration of CD34(+) cells in basal conditions or in response to vascular endothelial growth factor (VEGF) or stromal-derived factor 1 alpha (SDF) compared with normoxia. Expression of ACE2 or MasR was increased relative to normoxia while ACE or AT1R expressions were unaltered. Luciferase activity was increased by hypoxia in cells transfected with the luciferase reporter plasmids coding for the ACE2- or MasR promoters relatively to the control. The effects of hypoxia were mimicked by VEGF or SDF under normoxia. Hypoxia-induced ADAM17-dependent shedding of functional ACE2 fragments. In mice undergoing HLI, increased expression/activity of ACE2 and MasR were observed in the circulating HSPCs. This study provides compelling evidence for the hypoxic upregulation of ACE2 and MasR in CD34(+) cells, which likely contributes to vascular repair.