Linked Life Data

10903992

Source:http://linkedlifedata.com/resource/pubmed/id/10903992

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2000-8-17
pubmed:abstractText
Asymmetrical dimethylarginine (ADMA) is an endogenous nitric oxide synthase inhibitor. It is formed by protein arginine N-methyltransferases (PRMTs), which utilize S-adenosylmethionine as methyl group donor. ADMA plasma concentration is elevated in hypercholesterolemia, leading to endothelial dysfunction and producing proatherogenic changes of endothelial cell function. Four different isoforms of human PRMTs have been identified. Because the release of ADMA from human endothelial cells is increased in the presence of native or oxidized LDL cholesterol, we investigated the potential involvement of PRMT activity and gene expression in this effect. We found that the production of ADMA by human endothelial cells is upregulated in the presence of methionine or homocysteine and inhibited by either of the methyltransferase inhibitors S-adenosylhomocysteine, adenosine dialdehyde, or cycloleucine. This effect is specific for ADMA but not symmetrical dimethylarginine. The upregulation of ADMA release by native and oxidized LDL is abolished by S-adenosylhomocysteine and by the antioxidant pyrrollidine dithiocarbamate. Furthermore, a methyl-(14)C label is transferred from S-adenosylmethionine to ADMA but not symmetrical dimethylarginine, in human endothelial cells. The expression of PRMTs is upregulated in the presence of native or oxidized LDL. Our data suggest that the production of ADMA by human endothelial cells is regulated by S-adenosylmethionine-dependent methyltransferases. This activity is upregulated by LDL cholesterol, which may be due in part to the enhanced gene expression of PRMTs. In concentrations reached by stimulation of methyltransferases (5 to 50 micromol/L), ADMA significantly inhibited the formation of (15)N-nitrite from L-[guanidino-(15)N(2)]arginine. These findings suggest a novel mechanism by which ADMA concentration is elevated in hypercholesterolemia, leading to endothelial dysfunction and atherosclerosis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0009-7330
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
87
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
99-105
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
LDL cholesterol upregulates synthesis of asymmetrical dimethylarginine in human endothelial cells: involvement of S-adenosylmethionine-dependent methyltransferases.
pubmed:affiliation
Institute of Clinical Pharmacology, Hannover Medical School, Germany. boeger.rainer@mh-hannover.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't