title: Role of DNA methyltransferase 1 on the altered eNOS expression in human umbilical endothelium from intrauterine growth restricted fetuses.
abstract: Reduced fetal growth associates with endothelial dysfunction and cardiovascular risk in both young and adult offspring and the nitric oxide (NO) system has been implicated in these effects. Epigenetic processes are likely to underlie such effects, but there is to date no evidence that endothelial dysfunction in early life results from epigenetic processes on key genes in the NO system, such as NOS3 (eNOS) and ARG2 (arginase-2). We determined basal DNA methylation status in NOS3 and ARG2 promoters, and DNA methyltransferase 1 (DNMT1) effect on eNOS and arginase-2 expression using human endothelial cells isolated from umbilical arteries (HUAEC) and veins (HUVEC) from control and intrauterine growth restricted (IUGR) fetuses. Compared with cells from control pregnancies, eNOS protein and mRNA levels were increased in HUAEC, but decreased in HUVEC, from IUGR, while arginase-2 levels were increased in IUGR-HUVEC. The NOS3 promoter showed a decrease in DNA methylation at CpG -352 in IUGR-HUAEC, and an increase in IUGR-HUVEC, when compared with control cells. Methylation in the hypoxia response element of the NOS3 promoter was increased in IUGR-HUAEC and decreased in HUVEC. Methylation in the AGR2 promoter in IUGR-HUVEC was decreased in a putative HRE, and without changes in IUGR-HUAEC. Silencing of DNMT1 expression normalized eNOS expression in IUGR endothelial cells, and restored the normal response to hypoxia in HUVEC, without effects on arginase-2. This data suggest that eNOS expression in IUGR-derived endothelial cells is programmed by altered DNA methylation, and can be reversed by transient silencing of the DNA methylation machinery.
authors.affiliation: Division of Obstetrics and Gynaecology; School of Medicine; Pontificia Universidad Católica de Chile; Santiago, Chile.
authors.forename: Bernardo J
authors.initials: BJ
authors.lastname: Krause
authors.forename: Paula M
authors.initials: PM
authors.lastname: Costello
authors.forename: Ernesto
authors.initials: E
authors.lastname: Muñoz-Urrutia
authors.forename: Karen A
authors.initials: KA
authors.lastname: Lillycrop
authors.forename: Mark A
authors.initials: MA
authors.lastname: Hanson
authors.forename: Paola
authors.initials: P
authors.lastname: Casanello
mesh_terms: D000328:Adult; D001119:Arginase / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites; D015687:Cell Hypoxia; D002478:Cells, Cultured; D018899:CpG Islands; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism*; D019175:DNA Methylation; D042783:Endothelial Cells / Q000201:enzymology*; D044127:Epigenesis, Genetic; D005260:Female; D005317:Fetal Growth Retardation / Q000201:enzymology*; D005333:Fetus; D018507:Gene Expression Regulation, Developmental; D055785:Gene Knockdown Techniques; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D008297:Male; D052250:Nitric Oxide Synthase Type III / Q000235:genetics* / Q000378:metabolism; D011247:Pregnancy; D011401:Promoter Regions, Genetic; D020218:Response Elements
chemical_list: C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; C000619380:DNMT1 protein, human; C477631:ARG2 protein, human; D001119:Arginase
keywords: DNA methylation; NOS3; arginase-2; eNOS; fetal programming; human endothelial cells; intrauterine growth restriction