Nidogen-2 Maintains the Contractile Phenotype of Vascular Smooth Muscle Cells and Prevents Neointima Formation via Bridging Jagged1-Notch3 Signaling

Abstract

Background: How the extracellular matrix (ECM) microenvironment modulates the contractile phenotype of vascular smooth muscle cells (VSMCs) and confers vascular homeostasis remains elusive. Methods: To explore the key ECM proteins in the maintenance of the contractile phenotype of VSMCs, we applied protein-protein interaction (PPI) network analysis to explore novel ECM proteins associated with the VSMC phenotype. By combining in vitro and in vivo genetic mice vascular injury model, we identified nidogen-2, a basement membrane (BM) glycoprotein, as a key ECM protein for maintenance of vascular smooth muscle cell identity. Results: We collected a VSMC phenotype-related gene dataset (VSMCPRG dataset) by using Gene Ontology (GO) annotation combined with a literature search. A computational analysis of protein-protein interactions between ECM protein genes and the genes from the VSMCPRG dataset revealed the candidate gene nidogen-2, a BM glycoprotein involved in regulation of the VSMC phenotype. Indeed, nidogen-2-deficient VSMCs exhibited loss of contractile phenotype in vitro , and compared with wild-type (WT) mice, nidogen-2 -/- mice showed aggravated post-wire injury neointima formation of carotid arteries. Further bioinformatics analysis, co-immunoprecipitation assays and luciferase assays revealed that nidogen-2 specifically interacted with Jagged1, a conventional Notch ligand. Nidogen-2 maintained the VSMC contractile phenotype via Jagged1-Notch3 signaling but not Notch1 or Notch2 signaling. Notably, nidogen-2 enhanced Jagged1 and Notch3 interaction and subsequent Notch3 activation. Reciprocally, Jagged1 and Notch3 interaction, signaling activation, and Jagged1-triggered VSMC differentiation were significantly repressed in nidogen-2-deficient VSMCs. In accordance, the suppressive effect of Jagged1 overexpression on neointima formation was attenuated in nidogen-2 -/- mice compared to wild-type mice. Conclusions: Nidogen-2 maintains the contractile phenotype of VSMCs through Jagged1-Notch3 signaling in vitro and in vivo . Nidogen-2 is required for Jagged1-Notch3 signaling.

Inflammation and atherosclerosis: signaling pathways and therapeutic intervention

“… 246 Jagged1-Notch3 signaling mediates nidogen-2 to maintain the contractile phenotype of VSMCs through in vitro and in vivo. 247 Although abundant studies have identified that Notch has a central role in the control of SMC development and function, and intimal repair, much less is known about its role in the fate of VSMCs in atherosclerotic development and progression. Recent studies demonstrated that Notch signaling is required for the adhesion of VSMCs but not other types of VSMC-derived cells in the formation of the cap in mouse atherosclerosis, and reduction of Notch signaling is a prerequisite for medial VSMC mediating the development of plaque, 248 suggesting that sequential loss and gain of Notch signaling is required for the recruitment of cap SMC population in atherosclerosis.…”

Notch signalling in healthy and diseased vasculature

“…The discovery that Notch3 regulates PDGFRB links two important signalling pathways in VSMC differentiation and a Notch–PDGF signalling axis may in fact not be restricted only to mural cells, as it was recently observed that a NOTCH3 gain-of-function (NOTCH3 L1519P ) elevated PDGFRB expression in infantile myofibromatosis, a non-metastatic cancer formed in bone, skin and muscle [ 70 ]. Progress is also made in understanding the mechanistic details of Notch3 function in VSMCs, and the basement membrane protein Nidogen-2 was recently found to interact with Jagged1 and stabilize the Jagged1–Notch3 interaction [ 71 ].…”

Role of advanced glycation end products on vascular smooth muscle cells under diabetic atherosclerosis

“…Nidogen-2 is a basement membrane glycoprotein that enhances the interaction between Jagged1 and Notch3 and subsequent Notch3 activation. Compared with wild-type mice, Jagged1 overexpression attenuated the inhibition of neointima formation in nidogen-2 -/- mice ( 90 ). Cyclic stretch enhances Nox1 mediated ROS production through MEF2B activation signal and causes VSMCs to switch to a synthetic phenotype ( 91 ).…”