Brief Research Report ARTICLE
Opposing effects on vascular smooth muscle cell proliferation and macrophage-induced inflammation reveal a protective role for the proresolving lipid mediator receptor ChemR23 in intimal hyperplasia
- 1Department of Medicine, Solna, Karolinska Institute (KI), Sweden
- 2Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spain
- 3University of Barcelona, Spain
- 4Karolinska University Hospital, Sweden
Intimal hyperplasia remains a significant clinical problem in for example coronary artery bypass graft failure. Since omega-3 fatty acids reduce intimal hyperplasia, we hypothesized that the G protein-coupled receptor ChemR23 for the omega-3-derived pro-resolving lipid mediator resolvin E1 drives those effects. ChemR23+/+ and ChemR23-/- mice were generated with or without introduction of the Caenorhabditis elegans fat-1 transgene, which leads to an endogenous omega-3 fatty acid synthesis and thus increasing the substrate for resolvin E1 formation. ChemR23 deletion significantly increased intimal hyperplasia 28 days after ligation of the left common carotid artery. Mice expressing the fat-1 transgene showed reduced intimal hyperplasia independently of ChemR23 expression. ChemR23-/- Vascular smooth muscle cells (VSMCs) exhibited a significantly lower proliferation compared with VSMCs derived from ChemR23+/+ mice. In contrast, ChemR23-/- peritoneal macrophages had significantly higher mRNA levels of pro-inflammatory cytokines compared with ChemR23+/+ macrophages. Finally, conditioned media transfer from ChemR23-/- macrophages to VSMCs significantly increased VSMC proliferation compared with conditioned media from ChemR23+/+ macrophages. Taken together, these results point to a dual effect of ChemR23 in resolution pharmacology by directly stimulating VSMC proliferation and at the same time suppressing macrophage-induced VSMC proliferation. In conclusion, these differential effects of ChemR23 signaling in VSMC and macrophages open up a novel notion for intimal hyperplasia pathophysiology, where ChemR23-transduced effects on the vascular wall may vary, and even be opposing, depending on the degrees of resolution of inflammation.
Keywords: Intimal hyperplasia, macrophage, omega-3, resolution of inflammation, smooth muscle cells
Received: 30 Sep 2018;
Accepted: 29 Oct 2018.
Edited by:Lucy V. Norling, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, United Kingdom
Reviewed by:Soon Yew Tang, University of Pennsylvania, United States
Asif J. Iqbal, University of Birmingham, United Kingdom
Copyright: © 2018 Artiach, Carracedo, Clària, Laguna-Fernandez and Bäck. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Magnus Bäck, Karolinska University Hospital, Stockholm, Sweden, email@example.com