Pigment Epithelium-Derived Factor (PEDF) as a Regulator of Wound Angiogenesis

Sci Rep. 2018 Jul 24;8(1):11142. doi: 10.1038/s41598-018-29465-9.

Abstract

Although the inflammatory and proliferative phases of wound healing have been well described, much less is known about how healing resolves. During the resolution phase, pruning of the capillary bed and maturation of capillaries occurs and influences the final strength and fidelity of the wound. PEDF, an endogenous anti-angiogenic factor, is produced in wounds and may contribute to the removal of capillaries during wound resolution. This study utilized PEDF-/- mice to examine how PEDF influences wound angiogenesis, particularly capillary density and permeability. The absence of PEDF led to transient changes in dermal wound closure and collagen content, but caused substantial changes in wound angiogenesis. Compared to wild type (WT) mice, wounds from PEDF-/- mice exhibited a significant increase in capillaries during the proangiogenic phase of repair, and a delay in capillary pruning. Conversely, the addition of rPEDF caused a reduction in capillary density within skin wounds in WT mice. In vitro studies showed that PEDF inhibited migration and tube formation by dermal microvascular endothelial cells, and caused a decrease in the expression of VEGFR2, VCAM-1, and other surface receptors. The results demonstrate that loss of PEDF causes a distinctive wound healing phenotype that is characterized by increased angiogenesis and delayed resolution. The findings suggest that PEDF most likely acts through multiple mechanisms to regulate proper capillary refinement in wounds.

Publication types

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

MeSH terms

  • Analysis of Variance
  • Animals
  • Apoptosis / drug effects
  • Capillaries / metabolism
  • Capillary Permeability / physiology
  • Cell Adhesion / drug effects
  • Cell Adhesion Molecules / metabolism
  • Cell Movement / drug effects
  • Cells, Cultured
  • Collagen / metabolism
  • Endothelial Cells / physiology
  • Eye Proteins / genetics
  • Eye Proteins / metabolism*
  • Eye Proteins / pharmacology*
  • Female
  • Humans
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Neovascularization, Physiologic / drug effects
  • Neovascularization, Physiologic / physiology*
  • Nerve Growth Factors / genetics
  • Nerve Growth Factors / metabolism*
  • Nerve Growth Factors / pharmacology*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / pharmacology
  • Serpins / genetics
  • Serpins / metabolism*
  • Serpins / pharmacology*
  • Skin / blood supply
  • Skin / cytology
  • Skin / injuries
  • Vascular Endothelial Growth Factor Receptor-2 / metabolism
  • Wound Healing / physiology*

Substances

  • Cell Adhesion Molecules
  • Eye Proteins
  • Nerve Growth Factors
  • Recombinant Proteins
  • Serpins
  • pigment epithelium-derived factor
  • Collagen
  • Kdr protein, mouse
  • Vascular Endothelial Growth Factor Receptor-2