Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA (A.K.P., M.W.-W., W.X., S.Y., T.M., J.L.).
Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University, Nashville, TN (Q.S.W.).
Arterioscler Thromb Vasc Biol. 2022 Sep;42(9):1169-1185. doi: 10.1161/ATVBAHA.122.317866. Epub 2022 Aug 4.
Endothelial dysfunction is a critical component in the pathogenesis of cardiovascular diseases and is closely associated with nitric oxide (NO) levels and oxidative stress. Here, we report on novel findings linking endothelial expression of CD70 (also known as CD27 ligand) with alterations in NO and reactive oxygen species.
CD70 expression was genetically manipulated in human aortic and pulmonary artery endothelial cells. Intracellular NO and hydrogen peroxide (HO) were measured using genetically encoded biosensors, and cellular phenotypes were assessed.
An unbiased phenome-wide association study demonstrated that polymorphisms in CD70 associate with vascular phenotypes. Endothelial cells treated with CD70-directed short-interfering RNA demonstrated impaired wound closure, decreased agonist-stimulated NO levels, and reduced eNOS (endothelial nitric oxide synthase) protein. These changes were accompanied by reduced NO bioactivity, increased 3-nitrotyrosine levels, and a decrease in the eNOS binding partner heat shock protein 90. Following treatment with the thioredoxin inhibitor auranofin or with agonist histamine, intracellular HO levels increased up to 80% in the cytosol, plasmalemmal caveolae, and mitochondria. There was increased expression of NADPH oxidase 1 complex and gp91phox; expression of copper/zinc and manganese superoxide dismutases was also elevated. CD70 knockdown reduced levels of the HO scavenger catalase; by contrast, glutathione peroxidase 1 expression and activity were increased. CD70 overexpression enhanced endothelial wound closure, increased NO levels, and attenuated the reduction in eNOS mRNA induced by TNFα.
Taken together, these data establish CD70 as a novel regulatory protein in endothelial NO and reactive oxygen species homeostasis, with implications for human vascular disease.
内皮功能障碍是心血管疾病发病机制中的一个关键组成部分，与一氧化氮 (NO) 水平和氧化应激密切相关。在这里，我们报告了一种新的发现，即内皮细胞表达 CD70（也称为 CD27 配体）与 NO 和活性氧的变化有关。
在人主动脉和肺动脉内皮细胞中遗传操纵 CD70 的表达。使用遗传编码的生物传感器测量细胞内的 NO 和过氧化氢 (HO)，并评估细胞表型。
一项无偏的表型全基因组关联研究表明，CD70 中的多态性与血管表型相关。用 CD70 靶向的小干扰 RNA 处理的内皮细胞表现出伤口闭合受损、激动剂刺激的 NO 水平降低和 eNOS（内皮型一氧化氮合酶）蛋白减少。这些变化伴随着 NO 生物活性降低、3-硝基酪氨酸水平升高以及 eNOS 结合伴侣热休克蛋白 90 减少。在用硫氧还蛋白抑制剂 auranofin 或激动剂组胺处理后，细胞溶质、质膜 caveolae 和线粒体中的细胞内 HO 水平增加了 80%。NADPH 氧化酶 1 复合物和 gp91phox 的表达增加；铜/锌和锰超氧化物歧化酶的表达也升高。CD70 敲低降低了 HO 清除剂过氧化氢酶的水平；相比之下，谷胱甘肽过氧化物酶 1 的表达和活性增加。CD70 过表达增强了内皮细胞的伤口闭合，增加了 NO 水平，并减轻了 TNFα 诱导的 eNOS mRNA 减少。
综上所述，这些数据确立了 CD70 作为内皮细胞中 NO 和活性氧稳态的一种新型调节蛋白，对人类血管疾病具有重要意义。
