Histone and DNA methylation-mediated epigenetic downregulation of endothelial Kruppel-like factor 2 by low-density lipoprotein cholesterol.
Arterioscler Thromb Vasc Biol
; 33(8): 1936-42, 2013 Aug.
Article
en En
| MEDLINE
| ID: mdl-23723375
ABSTRACT
OBJECTIVE:
Low-density lipoprotein (LDL) cholesterol induces endothelial dysfunction and is a major modifiable risk factor for coronary heart disease. Endothelial Kruppel-like Factor 2 (KLF2) is a transcription factor that is vital to endothelium-dependent vascular homeostasis. The purpose of this study is to determine whether and how LDL affects endothelial KLF2 expression. APPROACH ANDRESULTS:
LDL downregulates KLF2 expression and promoter activity in endothelial cells. LDL-induced decrease in KLF2 parallels changes in endothelial KLF2 target genes thrombomodulin, endothelial NO synthase, and plasminogen activator inhibitor-1. Pharmacological inhibition of DNA methyltransferases or knockdown of DNA methyltransferase 1 prevents downregulation of endothelial KLF2 by LDL. LDL induces endothelial DNA methyltransferase 1 expression and DNA methyltransferase activity. LDL stimulates binding of the DNA methyl-CpG-binding protein-2 and histone methyltransferase enhancer of zeste homolog 2, whereas decreases binding of the KLF2 transcriptional activator myocyte enhancing factor-2, to the KLF2 promoter in endothelial cells. Knockdown of myocyte enhancing factor-2, or mutation of the myocyte enhancing factor-2 site in the KLF2 promoter, abrogates LDL-induced downregulation of endothelial KLF2 and thrombomodulin, and KLF2 promoter activity. Similarly, knockdown of enhancer of zeste homolog 2 negates LDL-induced downregulation of KLF2 and thrombomodulin in endothelial cells. Finally, overexpression of KLF2 rescues LDL-induced clotting of platelet-rich plasma on endothelial cells.CONCLUSIONS:
LDL represses endothelial KLF2 expression via DNA and histone methylation. Downregulation of KLF2 by LDL leads to a dysfunctional, hypercoagulable endothelium.Palabras clave
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Metilación de ADN
/
Células Endoteliales
/
Epigénesis Genética
/
Factores de Transcripción de Tipo Kruppel
/
LDL-Colesterol
Tipo de estudio:
Risk_factors_studies
Idioma:
En
Revista:
Arterioscler Thromb Vasc Biol
Asunto de la revista:
ANGIOLOGIA
Año:
2013
Tipo del documento:
Article