1. Fibulin-1 Integrates Subendothelial Extracellular Matrices and Contributes to Anatomical Closure of the Ductus Arteriosus
- Author
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Naoki Nicho, Toshihide Asou, Marion A. Cooley, Yuko Kato, Munetaka Masuda, Taichi Nakakoji, Utako Yokoyama, Junichi Saito, Takayuki Fujita, Satoko Ito, Sonoko Hatano, Masanari Umemura, Takako Sasaki, Yoshihiro Ishikawa, and Shiho Iwasaki
- Subjects
Neointima ,Matrix remodeling ,mice ,Mice, 129 Strain ,fibulin ,extracellular matrix ,vascular remodeling ,Myocytes, Smooth Muscle ,Closure (topology) ,Extracellular matrix ,Organ Culture Techniques ,Cell Movement ,Ductus arteriosus ,medicine.artery ,medicine ,Extracellular ,Animals ,Humans ,Rats, Wistar ,Ductus Arteriosus, Patent ,Cells, Cultured ,Protein Kinase C ,Mice, Knockout ,Aorta ,business.industry ,Basic Sciences ,Calcium-Binding Proteins ,NF-kappa B ,Endothelial Cells ,Anatomy ,Ductus Arteriosus ,neointima ,Coculture Techniques ,Fibulin ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Type C Phospholipases ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,Cardiology and Cardiovascular Medicine ,business ,versicans ,Receptors, Prostaglandin E, EP4 Subtype ,Signal Transduction - Abstract
Supplemental Digital Content is available in the text., Objective: 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 (Fbln1−/−) 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 (Ptger4−/−) 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. Conclusions: 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.
- Published
- 2020