Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom; Department of Pharmacology and Toxicology, Pharmacy College, King Saud University, Riyadh, P.O. Box 145111, Saudi Arabia(1).
Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom; Cardiovascular Metabolism, Novartis Institutes for Biomedical Research, 22 Windsor Street, Cambridge, MA 02139, USA.
Biochem Pharmacol. 2023 Oct;216:115795. doi: 10.1016/j.bcp.2023.115795. Epub 2023 Sep 9.
Prolonged vasoconstrictor signalling found in hypertension, increases arterial contraction, and alters vessel architecture by stimulating arterial smooth muscle cell (ASMC) growth, underpinning the development of re-stenosis lesions and vascular remodelling. Vasoconstrictors interact with their cognate G protein coupled receptors activating a variety of signalling pathways to promote smooth muscle proliferation. Here, angiotensin II (AngII) and endothelin 1 (ET1), but not UTP stimulates ASMC proliferation. Moreover, siRNA-mediated depletion of endogenous GRK2 expression, or GRK2 inhibitors, compound 101 or paroxetine, prevented AngII and ET1-promoted ASMC growth. Depletion of GRK2 expression or inhibition of GRK2 activity ablated the prolonged phase of AngII and ET-stimulated ERK signalling, while enhancing and prolonging UTP-stimulated ERK signalling. Increased GRK2 expression enhanced and prolonged AngII and ET1-stimulated ERK signalling, but suppressed UTP-stimulated ERK signalling. In ASMC prepared from 6-week-old WKY and SHR, AngII and ET1-stimulated proliferation rates were similar, however, in cultures prepared from 12-week-old rats AngII and ET1-stimulated growth was enhanced in SHR-derived ASMC, which was reversed following depletion of GRK2 expression. Furthermore, in ASMC cultures isolated from 6-week-old WKY and SHR rats, AngII and ET1-stimulated ERK signals were similar, while in cultures from 12-week-old rats ERK signals were both enhanced and prolonged in SHR-derived ASMC, and were reversed to those seen in age-matched WKY-derived ASMC following pre-treatment of SHR-derived ASMC with compound 101. These data indicate that the presence of GRK2 and its catalytic activity are essential to enable pro-proliferative vasoconstrictors to promote growth via recruitment and activation of the ERK signalling pathway in ASMC.
在高血压中发现的血管收缩信号持续时间延长，通过刺激动脉平滑肌细胞 (ASMC) 生长增加动脉收缩，并改变血管结构，为再狭窄病变和血管重塑的发展奠定基础。血管收缩剂与其同源 G 蛋白偶联受体相互作用，激活多种信号通路，促进平滑肌增殖。在这里，血管紧张素 II (AngII) 和内皮素 1 (ET1)，而不是 UTP，刺激 ASMC 增殖。此外，siRNA 介导的内源性 GRK2 表达耗竭，或 GRK2 抑制剂化合物 101 或帕罗西汀，可防止 AngII 和 ET1 促进的 ASMC 生长。GRK2 表达耗竭或 GRK2 活性抑制消除了 AngII 和 ET 刺激的 ERK 信号的延长阶段，同时增强和延长了 UTP 刺激的 ERK 信号。GRK2 表达的增加增强并延长了 AngII 和 ET1 刺激的 ERK 信号，但抑制了 UTP 刺激的 ERK 信号。在 WKY 和 SHR 6 周龄 ASMC 中，AngII 和 ET1 刺激的增殖率相似，但在 12 周龄大鼠培养物中，AngII 和 ET1 刺激的生长在 SHR 衍生的 ASMC 中增强，这在 GRK2 表达耗竭后得到逆转。此外，在从 WKY 和 SHR 大鼠分离的 ASMC 培养物中，AngII 和 ET1 刺激的 ERK 信号相似，而在来自 12 周龄大鼠的培养物中，ERK 信号在 SHR 衍生的 ASMC 中均增强和延长，并在 SHR 衍生的 ASMC 用化合物 101 预处理后恢复为与年龄匹配的 WKY 衍生的 ASMC 中所见的信号。这些数据表明，GRK2 的存在及其催化活性对于使促增殖的血管收缩剂能够通过募集和激活 ASMC 中的 ERK 信号通路来促进生长是必不可少的。
