Ethanol Downregulates Transcription of the PAI-1 Gene in Cultured Human Endothelial Cells

Thromb Res. 2000 Feb 15;97(4):247-55. doi: 10.1016/s0049-3848(99)00172-3.

Abstract

Human endothelial cells are a major site of synthesis for plasminogen activator inhibitor type-1. Elevated plasminogen activator inhibitor type-1 levels in young survivors of myocardial infarction [1] suggest that plasminogen activator inhibitor type-1 may have an important pathologic role in the development of coronary artery disease. Epidemiological studies indicate that moderate alcohol consumption (1-2 drinks/day) reduces the risk for cardiovascular mortality. This cardioprotective benefit has been attributed in part to an increase in fibrinolysis, which decreases fibrin-based thrombosis. The studies described herein were performed to determine whether moderate levels of ethanol affect plasminogen activator inhibitor type-1 gene expression. Cultured human endothelial cells were exposed to 0.1% v/v ethanol for 1 hour. Following incubation in the absence of ethanol plasminogen activator inhibitor type-1, mRNA levels were decreased in a time- and dose-dependent manner, reaching a maximum decrease of 3- to 4-fold at 2 to 4 hours following ethanol challenge. This decline in mRNA occurs at the transcription level; therefore, nuclear transcription run-on assays were performed. A 2.5- to 5-fold decrease in the rate of plasminogen activator inhibitor type-1 gene transcription was measured at 2 and 4 hours following ethanol challenge. Next, a 3.4- and a 1.1-kb fragment from the plasminogen activator inhibitor type-1 promoter region were linked to a luciferase reporter gene, and these constructs were transfected into human endothelial cells. Treatment of these transiently transfected human endothelial cells with ethanol showed a 2- to 3.5-fold decrease in promoter activity, respectively. These results indicate that low doses of ethanol downregulate transcription of the plasminogen activator inhibitor type-1 gene in cultured human endothelial cells. However, the mechanism(s) for this transcriptional decrease is currently unknown.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cells, Cultured
  • Down-Regulation / drug effects*
  • Endothelium, Vascular / drug effects*
  • Endothelium, Vascular / physiology
  • Ethanol / pharmacology*
  • Humans
  • Plasminogen Activator Inhibitor 1 / biosynthesis
  • Plasminogen Activator Inhibitor 1 / genetics*
  • Promoter Regions, Genetic / drug effects
  • Promoter Regions, Genetic / genetics
  • RNA, Messenger / biosynthesis
  • RNA, Messenger / drug effects
  • Transcription, Genetic / drug effects
  • Transfection
  • Umbilical Veins

Substances

  • Plasminogen Activator Inhibitor 1
  • RNA, Messenger
  • Ethanol