The G protein-coupled oestrogen receptor 1 agonist G-1 disrupts endothelial cell microtubule structure in a receptor-independent manner

Mol Cell Biochem. 2012 Jul;366(1-2):239-49. doi: 10.1007/s11010-012-1301-3. Epub 2012 Mar 27.

Abstract

The G protein-coupled oestrogen receptor GPER1, also known as GPR30, has been implicated in oestrogen signalling, but the physiological importance of GPER1 is not fully understood. The GPER1 agonist G-1 has become an important tool to assess GPER1-mediated cellular effects. Here, we report that this substance, besides acting via GPER1, affects the microtubule network in endothelial cells. Treatment with G-1 (3 μM) for 24 h reduced DNA synthesis by about 60 % in mouse microvascular endothelial bEnd.3 cells. Treatment with 3 μM G-1 prevented outgrowth of primary endothelial cells from mouse aortic explants embedded in Matrigel. Treatment with G-1 (0.3-3 μM) for 24 h disrupted bEnd.3 cell and HUVEC microtubule structure in a concentration-dependent manner as assessed by laser-scanning confocal immunofluorescence microscopy. G-1-induced (3 μM) disruption of microtubule was observed also after acute (3 and 6 h) treatment and in the presence of the protein synthesis inhibitor cycloheximide. Disruption of microtubules by 3 μM G-1 was observed in aortic smooth muscle cells obtained from both GPER1 knockout and wild-type mice, suggesting that G-1 influences microtubules through a mechanism independent of GPER1. G-1 dose dependently (10-50 μM) stimulated microtubule assembly in vitro. On the other hand, microtubules appeared normal in the presence of 10-50 μM G-1 as determined by electron microscopy. We suggest that G-1-promoted endothelial cell anti-proliferation is due in part to alteration of microtubule organization through a mechanism independent of GPER1. This G-1-promoted mechanism may be used to block unwanted endothelial cell proliferation and angiogenesis such as that observed in, e.g. cancer.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Aorta / cytology
  • Aorta / drug effects
  • Cell Proliferation
  • Cells, Cultured
  • Cyclopentanes / pharmacology*
  • DNA-Directed DNA Polymerase / drug effects
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism*
  • Endothelial Cells / physiology
  • Endothelial Cells / ultrastructure
  • Female
  • Gene Expression / drug effects
  • Humans
  • Kinetics
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Microtubules / drug effects*
  • Microtubules / metabolism
  • Myocytes, Smooth Muscle / drug effects
  • Myocytes, Smooth Muscle / metabolism
  • Myocytes, Smooth Muscle / ultrastructure
  • Protein Multimerization / drug effects
  • Quinolines / pharmacology*
  • Receptors, Estrogen / agonists*
  • Receptors, Estrogen / genetics
  • Receptors, Estrogen / metabolism
  • Receptors, G-Protein-Coupled / agonists*
  • Receptors, G-Protein-Coupled / genetics
  • Receptors, G-Protein-Coupled / metabolism
  • Tissue Culture Techniques
  • Tubulin Modulators / pharmacology*
  • Vascular Endothelial Growth Factor A / genetics
  • Vascular Endothelial Growth Factor A / metabolism
  • Vascular Endothelial Growth Factor Receptor-1 / genetics
  • Vascular Endothelial Growth Factor Receptor-1 / metabolism
  • Vascular Endothelial Growth Factor Receptor-2 / genetics
  • Vascular Endothelial Growth Factor Receptor-2 / metabolism

Substances

  • 1-(4-(6-bromobenzo(1,3)dioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta(c)quinolin-8-yl)ethanone
  • Cyclopentanes
  • GPER1 protein, human
  • Quinolines
  • Receptors, Estrogen
  • Receptors, G-Protein-Coupled
  • Tubulin Modulators
  • Vascular Endothelial Growth Factor A
  • vascular endothelial growth factor A, mouse
  • Vascular Endothelial Growth Factor Receptor-1
  • Vascular Endothelial Growth Factor Receptor-2
  • DNA replicase
  • DNA-Directed DNA Polymerase