Oxidized LDL and lysophosphatidylcholine stimulate plasminogen activator inhibitor-1 expression through reactive oxygen species generation and ERK1/2 activation in 3T3-L1 adipocytes.
Biochim Biophys Acta
; 1811(3): 153-62, 2011 Mar.
Article
em En
| MEDLINE
| ID: mdl-21146630
ABSTRACT
Plasminogen activator inhibitor-1 (PAI-1) is secreted from adipose tissue and is considered to be a risk factor for both atherosclerosis and insulin resistance. Here we report for the first time that PAI-1 expression is enhanced by oxidized low-density lipoprotein (OxLDL) and its lipid component lysophosphatidylcholine (LPC) in mouse 3T3-L1 adipocytes. In fully differentiated 3T3-L1 cells, OxLDL treatment increased the mRNA expression and protein secretion of PAI-1 in a dose- and time-dependent manner, whereas native LDL had no effect. The addition of an anti-CD36 antibody suppressed OxLDL-stimulated PAI-1 expression by 50%, suggesting that adipose-derived CD36 contributes to roughly half of the PAI-1 expression stimulated by OxLDL. In addition, pharmacological experiments showed that the OxLDL-stimulated enhancement in PAI-1 expression was mediated through the generation of reactive oxygen species (ROS) and phosphorylation of extracellular signal-regulated kinase 1/2. Furthermore, LPC, a major lipid component of OxLDL, was responsible for the enhanced expression of PAI-1 as phospholipase A(2)-treated acetyl LDL, which generates LPC, strongly stimulated PAI-1 expression, whereas acetyl LDL itself had no such activity. These data demonstrate that the uptake of OxLDL and, in particular, its lipid component LPC into adipocytes triggers aberrant ROS-mediated PAI-1 expression, which may be involved in the pathogenesis of metabolic syndrome.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Lisofosfatidilcolinas
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Espécies Reativas de Oxigênio
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Inibidor 1 de Ativador de Plasminogênio
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Adipócitos
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Proteína Quinase 3 Ativada por Mitógeno
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Lipoproteínas LDL
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article