title: Inhibiting DNA Methylation by 5-Aza-2'-deoxycytidine ameliorates atherosclerosis through suppressing macrophage inflammation.
abstract: Inflammation marks all stages of atherogenesis. DNA hypermethylation in the whole genome or specific genes is associated with inflammation and cardiovascular diseases. Therefore, we aimed to study whether inhibiting DNA methylation by DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-aza-dC) ameliorates atherosclerosis in low-density lipoprotein receptor knockout (Ldlr(-/-)) mice. Ldlr(-/-) mice were fed an atherogenic diet and adminisered saline or 5-aza-dC (0.25 mg/kg) for up to 30 weeks. 5-aza-dC treatment markedly decreased atherosclerosis development in Ldlr(-/-) mice without changes in body weight, plasma lipid profile, macrophage cholesterol levels and plaque lipid content. Instead, this effect was associated with decreased macrophage inflammation. Macrophages with 5-aza-dC treatment had downregulated expression of genes involved in inflammation (TNF-α, IL-6, IL-1β, and inducible nitric oxidase) and chemotaxis (CD62/L-selectin, chemokine [C-C motif] ligand 2/MCP-1 [CCL2/MCP-1], CCL5, CCL9, and CCL2 receptor CCR2). This resulted in attenuated macrophage migration and adhesion to endothelial cells and reduced macrophage infiltration into atherosclerotic plaques. 5-aza-dC also suppressed macrophage endoplasmic reticulum stress, a key upstream signal that activates macrophage inflammation and apoptotic pathways. Finally, 5-aza-dC demethylated liver X receptor α (LXRα) and peroxisome proliferator-activated receptor γ1 (PPARγ1) promoters, which are both enriched with CpG sites. This led to overexpression of LXRα and PPARγ, which may be responsible for 5-aza-dC's anti-inflammatory and atheroprotective effect. Our findings provide strong evidence that DNA methylation may play a significant role in cardiovascular diseases and serve as a therapeutic target for prevention and treatment of atherosclerosis.
authors.affiliation: Department of Biology and Center for Obesity Reversal (Q.C., H.S., B.X.), Georgia State University, Atlanta, Georgia; Departments of Internal Medicine (Q.C., X.W., A.K.M., A.D., G.A.H., S.K.D., H.S., B.X.) and Pathology (J.S.P.), Wake Forest School of Medicine, Winston-Salem, North Carolina; Department of Internal Medicine (L.J.), University of Texas, Southwestern Medical Center, Dallas, Texas; Department of Animal and Avian Sciences (L.Y.), University of Maryland, College Park, Maryland; and Department of Biochemistry and Molecular Biology (H.S.), Georgia Regents University, Augusta, Georgia.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Cao
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Wang
authors.forename: Lin
authors.initials: L
authors.lastname: Jia
authors.forename: Ashis K
authors.initials: AK
authors.lastname: Mondal
authors.forename: Abdoulaye
authors.initials: A
authors.lastname: Diallo
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Hawkins
authors.forename: Swapan K
authors.initials: SK
authors.lastname: Das
authors.forename: John S
authors.initials: JS
authors.lastname: Parks
authors.forename: Liqing
authors.initials: L
authors.lastname: Yu
authors.forename: Huidong
authors.initials: H
authors.lastname: Shi
authors.forename: Hang
authors.initials: H
authors.lastname: Shi
authors.forename: Bingzhong
authors.initials: B
authors.lastname: Xue
mesh_terms: D000818:Animals; D050197:Atherosclerosis / Q000097:blood / Q000209:etiology* / Q000473:pathology; D001374:Azacitidine / Q000031:analogs & derivatives; D002448:Cell Adhesion; D002465:Cell Movement; D002478:Cells, Cultured; D019175:DNA Methylation; D000077209:Decitabine; D059865:Endoplasmic Reticulum Stress; D008055:Lipids / Q000097:blood; D000071518:Liver X Receptors; D008264:Macrophages / Q000502:physiology*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D057093:Orphan Nuclear Receptors / Q000235:genetics; D047495:PPAR gamma / Q000235:genetics; D058226:Plaque, Atherosclerotic / Q000473:pathology; D011401:Promoter Regions, Genetic; D011897:Random Allocation; D051381:Rats
chemical_list: D008055:Lipids; D000071518:Liver X Receptors; C000605214:Nr1h3 protein, mouse; C000605215:Nr1h3 protein, rat; D057093:Orphan Nuclear Receptors; D047495:PPAR gamma; D000077209:Decitabine; D001374:Azacitidine