TGF-beta1 induces mouse dendritic cells to express VEGF and its receptor (Flt-1) under hypoxic conditions

Exp Mol Med. 2010 Sep 30;42(9):606-13. doi: 10.3858/emm.2010.42.9.059.

Abstract

Angiogenesis is a multi-step process that involves the activation, proliferation, and migration of endothelial cells. We have recently shown that TGF-beta1 can induce mouse macrophages to produce VEGF, a potent angiogenic factor. In the present study, we explored whether TGF-beta1 has a similar effect on mouse dendritic cells. First, we show that under hypoxic conditions, TGF-beta1 induced the expression of VEGF transcripts in bone marrow-derived dendritic cells. Overexpression of Smad3/4 further augmented TGF-beta1-induced VEGF transcription, while overexpression of DN-Smad3 decreased VEGF transcription in DC2.4 cells, a mouse dendritic cell line. We also show that TGF-beta1 and Smads are involved in the induction of VEGF protein secretion. Interestingly, under the same conditions, the expression of VEGF receptor 1 (Flt-1) was also elevated at both the transcriptional and protein levels. Additionally, we found that the TGF-beta1-induced VEGF secretion in activated DC2.4 cells has wound-healing properties. Finally, Smad7 and Smurf1 negatively regulated the TGF-beta1-induced and Smad3/4-mediated VEGF expression. Taken together, these results indicate that TGF-beta1 can enhance the expression of VEGF and Flt-1 through the typical Smad pathway in mouse dendritic cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiogenesis Inhibitors / metabolism*
  • Animals
  • Cell Line
  • Dendritic Cells / metabolism*
  • Macrophages / metabolism
  • Mice
  • Mice, Inbred BALB C
  • RNA, Messenger / metabolism
  • Signal Transduction
  • Smad2 Protein / metabolism
  • Smad3 Protein / metabolism
  • Smad4 Protein / metabolism
  • Smad7 Protein / metabolism
  • Transforming Growth Factor beta1 / metabolism
  • Transforming Growth Factor beta1 / pharmacology*
  • Vascular Endothelial Growth Factor A / metabolism*
  • Vascular Endothelial Growth Factor Receptor-1 / metabolism*

Substances

  • Angiogenesis Inhibitors
  • RNA, Messenger
  • Smad2 Protein
  • Smad2 protein, mouse
  • Smad3 Protein
  • Smad3 protein, mouse
  • Smad4 Protein
  • Smad4 protein, mouse
  • Smad7 Protein
  • Smad7 protein, mouse
  • Transforming Growth Factor beta1
  • Vascular Endothelial Growth Factor A
  • vascular endothelial growth factor A, mouse
  • Flt1 protein, mouse
  • Vascular Endothelial Growth Factor Receptor-1