| First Author | Milstone DS | Year | 2015 |
| Journal | Circ Res | Volume | 117 |
| Issue | 2 | Pages | 166-77 |
| PubMed ID | 26034041 | Mgi Jnum | J:227109 |
| Mgi Id | MGI:5699729 | Doi | 10.1161/CIRCRESAHA.117.306666 |
| Citation | Milstone DS, et al. (2015) Differential role of an NF-kappaB transcriptional response element in endothelial versus intimal cell VCAM-1 expression. Circ Res 117(2):166-77 |
| abstractText | RATIONALE: Human and murine Vcam1 promoters contain 2 adjacent nuclear factor-kappaB (NF-kappaB)-binding elements. Both are essential for cytokine-induced transcription of transiently transfected promoter-reporter constructs. However, the relevance of these insights to regulation of the endogenous Vcam1 gene and to pathophysiological processes in vivo remained unknown. OBJECTIVE: Determine the role of the 5' NF-kappaB-binding element in expression of the endogenous Vcam1 gene. METHODS AND RESULTS: Homologous recombination in embryonic stem cells was used to inactivate the 5' NF-kappaB element in the Vcam1 promoter and alter 3 nucleotides in the 5' untranslated region to allow direct comparison of wild-type versus mutant allele RNA expression and chromatin configuration in heterozygous mice. Systemic treatment with inflammatory cytokines or endotoxin (lipopolysaccharide) induced lower expression of the mutant allele relative to wild-type by endothelial cells in the aorta, heart, and lungs. The mutant allele also showed lower endothelial expression in 2-week atherosclerotic lesions in Vcam1 heterozygous/low-density lipoprotein receptor-deficient mice fed a cholesterol-rich diet. In vivo chromatin immunoprecipitation assays of heart showed diminished lipopolysaccharide-induced association of RNA polymerase 2 and NF-kappaB p65 with the mutant promoter. In contrast, expression of mutant and wild-type alleles was comparable in intimal cells of wire-injured carotid artery and 4- to 12-week atherosclerotic lesions. CONCLUSIONS: This study highlights differences between in vivo and in vitro promoter analyses, and reveals a differential role for a NF-kappaB transcriptional response element in endothelial vascular cell adhesion molecule-1 expression induced by inflammatory cytokines or a cholesterol-rich diet versus intimal cell expression in atherosclerotic lesions and injured arteries. |
