Critical role of Rho-kinase and MEK/ERK pathways for angiotensin II-induced plasminogen activator inhibitor type-1 gene expression

Arterioscler Thromb Vasc Biol. 2001 May;21(5):868-73. doi: 10.1161/01.atv.21.5.868.

Abstract

Plasminogen activator inhibitor type-1 (PAI-1) plays an integral role not only in the regulation of fibrinolytic activity but also in the pathogenesis of atherosclerosis and hypertension. We investigated the signaling pathways of angiotensin II (Ang II) leading to PAI-1 gene expression. Ang II increased the PAI-1 mRNA and protein levels in a time- and dose-dependent manner through the Ang II type 1 receptor in vascular smooth muscle cells. PAI-1 gene promoter activity measured by luciferase assay was significantly increased by Ang II. PAI-1 mRNA stability was also increased by Ang II. Ang II-induced PAI-1 mRNA upregulation was inhibited by BAPTA-AM, genistein, and AG1478, suggesting that intracellular calcium, tyrosine kinase, and epidermal growth factor receptor transactivation are involved. Furthermore, PD98059, an inhibitor of extracellular signal-regulated kinase (ERK) kinase (MEK), almost completely suppressed Ang II-induced PAI-1 upregulation. Adenovirus-mediated overexpression of the dominant-negative form of Rho-kinase or Y27632, a Rho-kinase inhibitor, also completely prevented PAI-1 induction by Ang II without affecting Ang II-induced ERK activation. These data suggest that activation of MEK/ERK and Rho-kinase pathways plays a pivotal role in PAI-1 gene upregulation by Ang II. The Rho-kinase pathway may be a novel target to inhibit Ang II signaling, and its inhibition may be useful in the treatment of hypertension as well as atherosclerosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin II / pharmacology*
  • Animals
  • Calcium / physiology
  • Cells, Cultured
  • Enzyme Inhibitors / pharmacology
  • ErbB Receptors / metabolism
  • Flavonoids / pharmacology
  • Imidazoles / pharmacology
  • Intracellular Signaling Peptides and Proteins
  • MAP Kinase Kinase 1
  • MAP Kinase Signaling System*
  • Mitogen-Activated Protein Kinase 1 / antagonists & inhibitors
  • Mitogen-Activated Protein Kinase 1 / physiology*
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinase Kinases / physiology*
  • Mitogen-Activated Protein Kinases / antagonists & inhibitors
  • Mitogen-Activated Protein Kinases / physiology
  • Muscle, Smooth, Vascular / drug effects
  • Muscle, Smooth, Vascular / metabolism*
  • Plasminogen Activator Inhibitor 1 / biosynthesis
  • Plasminogen Activator Inhibitor 1 / genetics*
  • Protein Serine-Threonine Kinases / physiology*
  • Pyridines / pharmacology
  • RNA Processing, Post-Transcriptional
  • RNA, Messenger / biosynthesis
  • Rats
  • Rats, Sprague-Dawley
  • Up-Regulation
  • rho-Associated Kinases

Substances

  • Enzyme Inhibitors
  • Flavonoids
  • Imidazoles
  • Intracellular Signaling Peptides and Proteins
  • Plasminogen Activator Inhibitor 1
  • Pyridines
  • RNA, Messenger
  • Angiotensin II
  • ErbB Receptors
  • Protein Serine-Threonine Kinases
  • rho-Associated Kinases
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases
  • MAP Kinase Kinase 1
  • Mitogen-Activated Protein Kinase Kinases
  • SB 203580
  • 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one
  • Calcium