Azithromycin attenuates fibroblast growth factors induced vascular endothelial growth factor via p38(MAPK) signaling in human airway smooth muscle cells

Cell Biochem Biophys. 2013 Nov;67(2):331-9. doi: 10.1007/s12013-011-9331-0.

Abstract

The airways in asthma and COPD are characterized by an increase in airway smooth muscle (ASM) mass and bronchial vascular changes associated with increased expression of pro-angiogenic growth factors, such as fibroblast growth factors (FGF-1 and FGF-2) and vascular endothelial growth factor (VEGF). We investigated the contribution of FGF-1/-2 in VEGF production in ASM cells and assessed the influence of azithromycin and dexamethasone and their underlying signaling mechanisms. Growth-synchronized human ASM cells were pre-treated with MAPK inhibitors, U0126 for ERK1/2(MAPK) and SB239063 for p38(MAPK) as well as with dexamethasone or azithromycin, 30 min before incubation with FGF-1 or FGF-2. Expression of VEGF (VEGF-A, VEGF121, and VEGF165) was assessed by quantitative PCR, VEGF release by ELISA and MAPK phosphorylation by Western blotting. Both FGF-1 and FGF-2 significantly induced mRNA levels of VEGF-A, VEGF121, and VEGF165. The VEGF protein release was increased 1.8-fold (FGF-1) and 5.5-fold (FGF-2) as compared to controls. Rapid transient increase in ERK1/2(MAPK) and p38(MAPK) phosphorylation and subsequent release of VEGF from FGF-1 or FGF-2-treated ASM cells were inhibited by respective blockers. Furthermore, azithromycin and dexamethasone significantly reduced both the VEGF release and the activation of p38(MAPK) pathway in response to FGF-1 or FGF-2 treatment. Our Results demonstrate that FGF-1 and FGF-2 up-regulate VEGF production via ERK1/2(MAPK) and p38(MAPK) pathways. Both azithromycin and dexamethasone elicited their anti-angiogenic effects via p38(MAPK) pathway in vitro, thereby suggesting a possible therapeutic approach to tackle VEGF-mediated vascular remodeling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Azithromycin / pharmacology*
  • Dexamethasone / pharmacology
  • Enzyme Activation / drug effects
  • Fibroblast Growth Factor 1 / antagonists & inhibitors
  • Fibroblast Growth Factor 1 / pharmacology*
  • Fibroblast Growth Factor 2 / antagonists & inhibitors
  • Fibroblast Growth Factor 2 / pharmacology*
  • Gene Expression Regulation / drug effects
  • Humans
  • Intracellular Space / drug effects
  • Intracellular Space / metabolism
  • MAP Kinase Signaling System / drug effects*
  • Myocytes, Smooth Muscle / cytology
  • Myocytes, Smooth Muscle / drug effects
  • Myocytes, Smooth Muscle / metabolism
  • Time Factors
  • Trachea / cytology*
  • Vascular Endothelial Growth Factor A / genetics
  • Vascular Endothelial Growth Factor A / metabolism*
  • p38 Mitogen-Activated Protein Kinases / metabolism*

Substances

  • Vascular Endothelial Growth Factor A
  • Fibroblast Growth Factor 2
  • Fibroblast Growth Factor 1
  • Dexamethasone
  • Azithromycin
  • p38 Mitogen-Activated Protein Kinases