Regulation of the expression balance of angiopoietin-1 and angiopoietin-2 by Shh and FGF-2

In Vitro Cell Dev Biol Anim. 2010 Jun;46(6):487-91. doi: 10.1007/s11626-009-9270-x. Epub 2010 Jan 29.

Abstract

Sonic hedgehog (Shh) is a typical morphogen to regulate epithelial-mesenchymal interactions during embryonic development. Shh is also an indirect angiogenic agent upregulating other angiogenic factors, including angiopoietin-1 (Ang-1). Recent studies revealed that angiogenesis induced by Shh is characterized by distinct large-diameter vessels with less branching. Ang-1 promotes blood vessel maturation, and angiopoietin-2 (Ang-2) counteracts Ang-1 activity and regulates vascular branching. Thus, we hypothesized that Shh-induced angiogenesis is affected by expression of Ang-1 and Ang-2, and we investigated the regulatory system of angiopoietins by Shh in vitro. Shh enhanced Ang-1 expression but did not enhance vascular endothelial growth factor in fibroblasts. The upregulation of Ang-1 expression by Shh was significantly decreased by fibroblast growth factor-2 (FGF-2), a potent angiogenic factor. Furthermore, FGF-2 increased the expression of Ang-2 in endothelial cells. These findings suggest that Shh and FGF-2 regulate the expression balance of vascular morphogens Ang-1 and Ang-2 and are involved in angiogenesis.

MeSH terms

  • Angiopoietin-1 / genetics*
  • Angiopoietin-1 / metabolism
  • Angiopoietin-2 / genetics*
  • Angiopoietin-2 / metabolism
  • Blood Vessels / growth & development
  • Endothelium, Vascular / metabolism
  • Fibroblast Growth Factor 2 / metabolism*
  • Gene Expression Regulation*
  • Hedgehog Proteins / metabolism*
  • Humans
  • RNA, Messenger / metabolism
  • Up-Regulation

Substances

  • Angiopoietin-1
  • Angiopoietin-2
  • Hedgehog Proteins
  • RNA, Messenger
  • Fibroblast Growth Factor 2