In:
Arteriosclerosis, Thrombosis, and Vascular Biology, Ovid Technologies (Wolters Kluwer Health), Vol. 38, No. Suppl_1 ( 2018-05)
Abstract:
Apabetalone (RVX-208) is a bromodomain & extraterminal (BET) protein inhibitor, an epigenetic modifier of gene expression, currently in a phase 3 major adverse cardiac events outcomes trial in post-acute coronary syndrome patients with type 2 diabetes mellitus (DM) (BETonMACE). CVD patients enrolled in phase 2b trials (ASSERT, SUSTAIN and ASSURE) demonstrated a 44% relative risk reduction in cardiovascular disease (CVD) events (Nicholls et al. 2017). In CVD and DM, elevated circulating cytokines potentiate vascular inflammation (VI) through recruitment of leukocytes to the vascular endothelium, which contributes to atherosclerosis and plaque rupture. Previous studies demonstrated that apabetalone has potent anti-inflammatory effects on human aortic endothelial cells (HAEC) and macrophage-like U937 cells. Here we show that TNFα stimulation induced significant adhesion of THP-1 monocytes to inflamed endothelial cells, an outcome reversed by apabetalone treatment under both static (human umbilical vein endothelial cells - HUVEC) and flow (HAEC) conditions. Mechanistically, apabetalone suppressed the TNFα and IL-1β-induced expression of mRNAs of multiple endothelial cell adhesion molecules (CD44, E-selectin, VCAM-1 and MCP-1) and inflammatory cytokines (IL-6, IL-8, IL-1β, and CSF2). Monocytes also respond to TNFα stimulation with an upregulation of inflammatory and adhesion marker expression. In THP-1 cells, apabetalone treatment significantly reduced mRNA expression of CCR1, CCR2, IL-1β, MCP-1, MYD88, TLR4, TNFα, and VLA-4. In the diet-induced obesity (DIO) mouse model that mimics metabolic syndrome, treatment with apabetalone, administered at 150 mg/kg BID for the last 16 weeks of a 22 week study, downregulated aortic adhesion markers (E-selectin and ICAM) and markers of infiltrating immune cells (CCR2 and CD11b). In summary, treatment with apabetalone causes transcriptional changes in monocytes and endothelial cells that translate into a reduction in adhesion under inflammatory conditions. We hypothesize that downregulation of VI by apabetalone may contribute to the reduction in CVD events observed in phase 2 studies. This hypothesis is currently being tested in the ongoing BETonMACE phase 3 trial.
Type of Medium:
Online Resource
ISSN:
1079-5642
,
1524-4636
DOI:
10.1161/atvb.38.suppl_1.257
Language:
English
Publisher:
Ovid Technologies (Wolters Kluwer Health)
Publication Date:
2018
detail.hit.zdb_id:
1494427-3
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