From the Cardiovascular Research Institute (S.I., U.Y., T.N., J.S., N.N., M.U., T.F., Y.I.), Yokohama City University, Japan.
Department of Physiology, Tokyo Medical University, Japan (S.I., U.Y., Y.K., J.S.).
Arterioscler Thromb Vasc Biol. 2020 Sep;40(9):2212-2226. doi: 10.1161/ATVBAHA.120.314729. Epub 2020 Jul 9.
The ductus arteriosus (DA) is a fetal artery connecting the aorta and pulmonary arteries. Progressive matrix remodeling, that is, intimal thickening (IT), occurs in the subendothelial region of DA to bring anatomic DA closure. IT is comprised of multiple ECMs (extracellular matrices) and migrated smooth muscle cells (SMCs). Because glycoprotein fibulin-1 binds to multiple ECMs and regulates morphogenesis during development, we investigated the role of fibulin-1 in DA closure. Approach and Results: Fibulin-1-deficient () mice exhibited patent DA with hypoplastic IT. An unbiased transcriptome analysis revealed that EP4 (prostaglandin E receptor 4) stimulation markedly increased fibulin-1 in DA-SMCs via phospholipase C-NFκB (nuclear factor κB) signaling pathways. Fluorescence-activated cell sorting (FACS) analysis demonstrated that fibulin-1 binding protein versican was derived from DA-endothelial cells (ECs). We examined the effect of fibulin-1 on directional migration toward ECs in association with versican by using cocultured DA-SMCs and ECs. EP4 stimulation promoted directional DA-SMC migration toward ECs, which was attenuated by either silencing fibulin-1 or versican. Immunofluorescence demonstrated that fibulin-1 and versican V0/V1 were coexpressed at the IT of wild-type DA, whereas 30% of versican-deleted mice lacking a hyaluronan binding site displayed patent DA. Fibulin-1 expression was attenuated in the EP4-deficient mouse () DA, which exhibits patent DA with hypoplastic IT, and fibulin-1 protein administration restored IT formation. In human DA, fibulin-1 and versican were abundantly expressed in SMCs and ECs, respectively.
Fibulin-1 contributes to DA closure by forming an environment favoring directional SMC migration toward the subendothelial region, at least, in part, in combination with EC-derived versican and its binding partner hyaluronan.
动脉导管（DA）是连接主动脉和肺动脉的胎儿动脉。在 DA 的血管内膜下区域，进行基质的进行性重塑，即内膜增厚（IT），以实现解剖学上的 DA 闭合。IT 由多种细胞外基质（ECM）和迁移的平滑肌细胞（SMC）组成。由于糖蛋白纤连蛋白-1与多种 ECM 结合，并在发育过程中调节形态发生，我们研究了纤连蛋白-1在 DA 闭合中的作用。
纤连蛋白-1 缺陷（）小鼠的 DA 持续开放，伴有 IT 发育不良。一项无偏倚的转录组分析显示，前列腺素 E 受体 4（EP4）刺激通过磷脂酶 C-NFκB（核因子 κB）信号通路显著增加 DA-SMC 中的纤连蛋白-1。荧光激活细胞分选（FACS）分析表明，纤连蛋白-1 结合蛋白 versican 来源于 DA 内皮细胞（EC）。我们通过共培养 DA-SMC 和 EC 来研究纤连蛋白-1与 versican 结合对其向 EC 定向迁移的影响。EP4 刺激促进了 DA-SMC 向 EC 的定向迁移，而沉默纤连蛋白-1或 versican 则减弱了这种迁移。免疫荧光显示，纤连蛋白-1和 versican V0/V1 在野生型 DA 的 IT 中共同表达，而缺乏透明质酸结合位点的 30% versican 缺失小鼠则出现持续开放的 DA。EP4 缺陷（）小鼠的 DA 中纤连蛋白-1表达减弱，其表现为 IT 发育不良的持续开放，纤连蛋白-1 蛋白给药可恢复 IT 形成。在人类 DA 中，纤连蛋白-1和 versican 分别在 SMC 和 EC 中大量表达。
纤连蛋白-1 通过形成有利于 SMC 向血管内膜下区域定向迁移的环境，至少部分与 EC 衍生的 versican 及其结合伴侣透明质酸一起，促进 DA 闭合。
