Exosomes derived from M1 macrophages aggravate neointimal hyperplasia following carotid artery injuries in mice through miR-222/CDKN1B/CDKN1C pathway

Zeng Wang,Rifeng Gao,Aijun Sun,Hong Zhu,Rongle Liu,Xiao Li,Junbo Ge,Kai Hu,Hongtao Shi,Huan Zhao,Yunzeng Zou,Xinyu Weng

doi:10.1038/s41419-019-1667-1

Abstract

The role of M1 macrophages (M1M)-derived exosomes in the progression of neointimal hyperplasia remains unclear now. Using a transwell co-culture system, we demonstrated that M1M contributed to functional change of vascular smooth muscle cell (VSMC). We further stimulated VSMCs with exosomes isolated from M1M. Our results demonstrated that these exosomes could be taken up by VSMCs through macropinocytosis. Using a microRNA array assay, we identified that miR-222 originated from M1M-derived exosomes triggered the functional changes of VSMCs. In addition, we confirmed that miR-222 played a key role in promoting VSMCs proliferation and migration by targeting Cyclin Dependent Kinase Inhibitor 1B (CDKN1B) and Cyclin Dependent Kinase Inhibitor 1C (CDKN1C) in vitro. In vivo, M1M-derived exosomes significantly aggravated neointima formation following carotid artery ligation injury and wire injury and these effects were partly abolished by miR-222 inhibitor 2′OMe-miR-222. Our findings thus suggest that exosomes derived from M1M could aggravate neointimal hyperplasia through delivering miR-222 into VSMCs. Future studies are warranted to validate if the post-injury vascular neointimal hyperplasia and restenosis could be attenuated by inhibiting miR-222.

Highlights

Percutaneous coronary interventions (PCI) have become the first choice for the treatment of acute coronary syndromes, but patients undergoing PCI face increased risk of restenosis[1]
We investigated whether and how exosomes derived from M1 macrophages (M1M) exert their role on carotid artery vascular remodeling, focusing on the mediating role of miR-222
To clarify whether M1M were involved in the process of proliferation and migration in SMCs, we co-cultured THP-1 derived M1M with HA-vascular smooth muscle cell (VSMC) in a transwell system, which allowed the transfer of cellular secretions but prevented the transfer of vesicles larger than exosomes and direct cell contact

Summary

Introduction

Percutaneous coronary interventions (PCI) have become the first choice for the treatment of acute coronary syndromes, but patients undergoing PCI face increased risk of restenosis[1]. Wang et al Cell Death and Disease (2019)10:422 can negatively regulate the expression of target genes by binding to its mRNA9,10. Several miRNAs such as miR-21, miR-126, miR-155, and miR-222 have been reported to play crucial roles in neointima formation and vascular remodeling[10,12,13,14,15]. It is known that miR-222 could promote the migration and proliferation of smooth muscle cells and is upregulated in neointima after balloon injury, but the origin of miR-222 is still an issue of debate[9,10,16]. Several target genes of miR-222 are found to be implicated in the development of vascular remodeling such as CDKN1B and CDKN1C17,18. We investigated whether and how exosomes derived from M1 macrophages (M1M) exert their role on carotid artery vascular remodeling, focusing on the mediating role of miR-222

Methods

Results

Conclusion