Abstract：
Hypertension is common in elderly population. We designed to search comprehensively for genes that are chronologically shifted in their expressions and to define their contributions to vascular aging and hypertension. RNA sequencing was conducted to search for senescence-shifted transcripts in human umbilical vein endothelial cells (HUVECs). Small interfering RNA (siRNA), small-molecule drugs, CRISPR/Cas9 techniques, and imaging were used to determine genes\' function and contributions to age-related phenotypes of the endothelial cell and blood vessel. Of 25 genes enriched in the term of \"regulation of blood pressure,\" NPRA was changed most significantly. The decreased NPRA expression was replicated in aortas of aged mice. The knockdown of NPRA promoted HUVEC senescence and it decreased expressions of protein kinase cGMP-dependent 1 (PKG), sirtuin 1 (SIRT1), and endothelial nitric oxide synthase (eNOS). Suppression of NPRA also decreased the phosphorylation of AMP-activated protein kinase (AMPK) as well as the ratio of oxidized nicotinamide adenine dinucleotide (NAD+ )/reduced nicotinamide adenine dinucleotide (NADH) but increased the production of reactive oxygen species (ROS). 8-Br-cGMP (analog of cGMP), or AICAR (AMPK activator), counteracted the observed changes in HUVECs. The Npr1+/- mice presented an elevated systolic blood pressure and their vessels became insensitive to endothelial-dependent vasodilators. Further, vessels from Npr1+/- mice increased Cdkn1a but decreased eNos expressions. These phenotypes were rescued by intravenously administrated 8-Br-cGMP and viral overexpression of human PKG, respectively. In conclusion, we demonstrate NPRA/PKG/AMPK as a novel and critical signaling axis in the modulation of endothelial cell senescence, vascular aging, and hypertension.
摘要：
高血压在老年人群中很常见。我们旨在全面搜索按时间顺序改变表达的基因，并定义它们对血管衰老和高血压的贡献。进行RNA测序以在人脐静脉内皮细胞(HUVEC)中搜索衰老移位的转录物。小干扰RNA(siRNA),小分子药物,CRISPR/Cas9技术，和成像用于确定基因的功能以及对内皮细胞和血管的年龄相关表型的贡献。在富含血压调节术语的25个基因中，“NPRA发生了最显著的变化。降低的NPRA表达在老年小鼠的主动脉中复制。NPRA的敲除促进了HUVEC的衰老，并降低了蛋白激酶cGMP依赖性1（PKG）的表达，沉默蛋白1(SIRT1)，和内皮型一氧化氮合酶(eNOS)。抑制NPRA还降低了AMP激活的蛋白激酶（AMPK）的磷酸化以及氧化的烟酰胺腺嘌呤二核苷酸（NAD）/还原的烟酰胺腺嘌呤二核苷酸（NADH）的比例，但增加了活性氧（ROS）的产生。8-Br-cGMP（cGMP类似物），或AICAR（AMPK激活剂），抵消了观察到的HUVECs变化。Npr1+/-小鼠呈现升高的收缩压,并且它们的血管变得对内皮依赖性血管扩张剂不敏感。Further,Npr1+/-小鼠的血管增加Cdkn1a，但降低eNos表达。这些表型通过静脉内施用8-Br-cGMP和人PKG的病毒过表达来拯救，分别。总之,我们证明了NPRA/PKG/AMPK是内皮细胞衰老调控中的一个新的关键信号轴,血管老化，和高血压。
