Ethanol-induced expression of ET-1 and ET-BR in liver sinusoidal endothelial cells and human endothelial cells involves hypoxia-inducible factor-1alpha and microrNA-199

J Immunol. 2009 Oct 15;183(8):5232-43. doi: 10.4049/jimmunol.0901084. Epub 2009 Sep 25.

Abstract

Chronic alcohol consumption leads to inflammation and cirrhosis of the liver. In this study, we observed that liver sinusoidal endothelial cells (LSEC) derived from ethanol-fed rats showed several fold increases in the mRNA expression of endothelin-1 (ET-1), hypoxia-inducible factor-1alpha (HIF-1alpha), and inflammatory cytochemokines compared with control rat LSEC. We also observed the same results in acute ethanol-treated LSEC from control rats and human dermal microvascular endothelial cells. Ethanol-mediated ET-1 expression involved NADPH oxidase and HIF-1alpha activation. Furthermore, ethanol increased the expression of the ET-1 cognate receptor ET-BR in Kupffer cells and THP-1 monocytic cells, which also involved HIF-1alpha activation. Promoter analysis and chromatin immunoprecipitation showed that hypoxia response element sites in the proximal promoter of ET-1 and ET-BR were required for the binding of HIF-1alpha to up-regulate their expression. We showed that microRNAs, miR-199 among several microRNAs, attenuated HIF-1alpha and ET-1 expression, while anti-miR-199 reversed the effects, suggesting that ethanol-induced miR-199 down-regulation may contribute to augmented HIF-1alpha and ET-1 expression. Our studies, for the first time to our knowledge, show that ethanol-mediated ET-1 and ET-BR expression involve HIF-1alpha, independent of hypoxia. Additionally, ethanol-induced ET-1 expression in rat LSEC is regulated by miR-199, while in human endothelial cells, ET-1 expression is regulated by miR-199 and miR-155, indicating that these microRNAs may function as novel negative regulators to control ET-1 transcription and, thus, homeostatic levels of ET-1 to maintain microcirculatory tone.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Line
  • Endothelial Cells / drug effects*
  • Endothelial Cells / immunology
  • Endothelial Cells / metabolism
  • Endothelin-1 / agonists
  • Endothelin-1 / biosynthesis*
  • Endothelin-1 / immunology
  • Ethanol / toxicity*
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / agonists
  • Hypoxia-Inducible Factor 1, alpha Subunit / immunology
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism*
  • Liver / drug effects*
  • Liver / metabolism
  • Liver / pathology
  • Male
  • MicroRNAs / metabolism*
  • NADPH Oxidases / immunology
  • NADPH Oxidases / metabolism
  • Promoter Regions, Genetic / immunology
  • Rats
  • Rats, Wistar
  • Receptor, Endothelin B / agonists
  • Receptor, Endothelin B / biosynthesis*
  • Receptor, Endothelin B / immunology
  • Up-Regulation / drug effects
  • Up-Regulation / immunology

Substances

  • Endothelin-1
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • MicroRNAs
  • Receptor, Endothelin B
  • mirn199 microRNA, human
  • Ethanol
  • NADPH Oxidases