Rivaroxaban Suppresses Atherosclerosis by Inhibiting FXa-Induced Macrophage M1 Polarization-Mediated Phenotypic Conversion of Vascular Smooth Muscle Cells

Abstract

Background: Factor Xa (FXa) is a mediator initiating and accelerating atherosclerosis (AS). Both macrophage and vascular smooth muscle cells (VSMCs) participate in AS progression. This study was aimed to investigate the mechanisms underlying the effects of the FXa inhibitor rivaroxaban on AS.Methods: Rivaroxaban was administered to AS mice. Primary macrophages were exposed to FXa, treated with rivaroxaban, and transfected with siRNA silencing protease-activated receptor 2 (PAR2), hypoxia-inducible factor 1α (HIF1α), delta-like receptor 4 (Dll4), and Akt. Interaction between macrophages and VSMCs was assessed by co-culturing systems. Atherosclerotic lesions were evaluated by oil red O stain. Fluorescent staining was used to determine the cell phenotypes. Secretions of inflammatory cytokines and collagen were assessed by ELISA and Sircol assays. Western blotting was used to evaluate the protein expression and phosphorylation levels.Results: Rivaroxaban reduced lesion area, accumulation of M1 macrophages, and contractile-synthetic phenotypic conversion of VSMCs in atherosclerotic plaques. FXa exposure induced polarization of macrophages toward M1 and Dll4 high expression, which were inhibited by PAR2, Akt1, and HIF1α silencing. Rivaroxaban treatment inhibited PAR2/Akt/HIF1α signaling activation and Dll4 expression in FXa-exposed macrophages. By cell-to-cell contact, M1 macrophages induced Notch signaling activation in VSMCs which committed contractile-synthetic conversion. Rivaroxaban treatment and Dll4 silencing incapacitated macrophage in inducing phenotypic conversion of VSMCs upon cell-to-cell contact.Conclusion: Rivaroxaban suppresses AS by inhibiting FXa-induced PAR2/Akt/HIF1α signaling activation-mediated macrophage M1 polarization and high Dll4 expression. These macrophages facilitated VSMCs to perform contractile-synthetic phenotypic conversion upon macrophage-VSMCs cell-to-cell contact.

Advanced Glycation End Products Induce Atherosclerosis via RAGE/TLR4 Signaling Mediated-M1 Macrophage Polarization-Dependent Vascular Smooth Muscle Cell Phenotypic Conversion

“…Contact and noncontact coculture models were adopted from our previous investigation [ 5 ] which was demonstrated in Figure 1(a) . According to previous descriptions, macrophages were cocultured with VSMCs in Millicell-24 Cell Culture Insert Plate system with polyethylene terephthalate membranes (Millipore) [ 21 , 22 ].…”

“…When challenged by harmful stimuli, VSMCs lose contractile properties and convert into synthetic phenotype which is critical in formation and progression of atherosclerotic plaques [ 2 ]. Ours and others' previous studies suggested that delta-like ligand 4- (Dll4-) activated Notch signaling pathway was indispensable in VSMC contractile-synthetic phenotypic conversion [ 3 – 5 ]. It was reported that Dll4 blockage effectively attenuated several metabolic disorders including atherosclerosis [ 6 ].…”

Effect of combining aspirin and rivaroxaban on atherosclerosis in mice

“…A study found that rivaroxaban reduced that proinflammatory effects of FXa on human umbilical vein endothelial cells [31]. It was also reported that FXa induces phenotypic conversion of vascular smooth muscle cells into macrophages [32]. A recent study demonstrated that rivaroxaban reduces atherosclerosis by preventing FXa-PAR2-dependent autophagy suppression [33].…”

Cardiovascular Risk After SARS-CoV-2 Infection Is Mediated by IL18/IL18R1/HIF-1 Signaling Pathway Axis

“…In addition to macrophage infiltration ( 24 , 25 ), phenotypic transformation of VSMCs is a key mechanism in aneurysms ( 26 ) and atherosclerosis ( 27 ), so as the endothelial dysfunction ( 28 , 29 ). It is noteworthy that macrophages have regulatory effects on vascular smooth muscle cells ( 30 ), endothelial cells and macrophages themselves ( 31 ). Meanwhile, macrophage infiltration was a pathological feature of the cardiovascular system after SARS-CoV-2 infection ( 32 ).…”