The Ionophoric Activity of a Pro-Apoptotic VEGF165 Fragment on HUVEC Cells

Int J Mol Sci. 2020 Apr 20;21(8):2866. doi: 10.3390/ijms21082866.

Abstract

Copper plays an important role as a regulator in many pathologies involving the angiogenesis process. In cancerogenesis, tumor progression, and angiogenic diseases, copper homeostasis is altered. Although many details in the pathways involved are still unknown, some copper-specific ligands have been successfully used as therapeutic agents. Copper-binding peptides able to modulate angiogenesis represent a possible way to value new drugs. We previously reported that a fragment (VEGF73-101) of vascular endothelial growth factor (VEGF165), a potent angiogenic, induced an apoptotic effect on human umbilical vein endothelial cells. The aim of this study was to investigate the putative copper ionophoric activity of VEGF73-101, as well as establish a relationship between the structure of the peptide fragment and the cytotoxic activity in the presence of copper(II) ions. Here, we studied the stoichiometry and the conformation of the VEGF73-101/Cu(II) complexes and some of its mutated peptides by electrospray ionization mass spectrometry and circular dichroism spectroscopy. Furthermore, we evaluated the effect of all peptides in the absence and presence of copper ions by cell viability and cytofuorimetric assays. The obtained results suggest that VEGF73-101 could be considered an interesting candidate in the development of new molecules with ionophoric properties as agents in antiangiogenic therapeutic approaches.

Keywords: ESI-MS; HUVEC; angiogenesis; apoptosis; copper; ionophore; membrane model; peptides; vascular endothelial growth factor.

MeSH terms

  • Amino Acid Sequence
  • Apoptosis* / drug effects
  • Apoptosis* / genetics
  • Cell Membrane Permeability
  • Cell Survival / drug effects
  • Chelating Agents / pharmacology
  • Copper / metabolism
  • Human Umbilical Vein Endothelial Cells / metabolism*
  • Humans
  • Hydrophobic and Hydrophilic Interactions
  • Neovascularization, Physiologic / drug effects
  • Neovascularization, Physiologic / genetics
  • Peptide Fragments / chemistry
  • Peptide Fragments / pharmacology
  • Protein Binding
  • Protein Conformation
  • Spectrometry, Mass, Electrospray Ionization
  • Spectrum Analysis
  • Structure-Activity Relationship
  • Vascular Endothelial Growth Factor A / chemistry
  • Vascular Endothelial Growth Factor A / genetics
  • Vascular Endothelial Growth Factor A / metabolism*
  • Vascular Endothelial Growth Factor A / pharmacology

Substances

  • Chelating Agents
  • Peptide Fragments
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • Copper