Premium
Basic fibroblast growth factor increases the effects of endotoxin and interferon gamma on iNOS and mouse aortic endothelial cells
Author(s) -
Liu Tongzheng,
Hoyt Dale G.
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.5.a525
Subject(s) - nitric oxide synthase , interferon gamma , interferon , endothelial stem cell , fibroblast growth factor , cell , basic fibroblast growth factor , lipopolysaccharide , cytokine , blot , microbiology and biotechnology , biology , immunology , pharmacology , growth factor , nitric oxide , endocrinology , biochemistry , in vitro , receptor , gene
Inflammatory cytokines and bacterial products, such as interferon gamma (IFN) and endotoxin (LPS) promote endothelial dysfunction. They induce the expression of inducible NO synthase (iNOS), which may play a role in the pathogenesis of vascular diseases. Basic fibroblast growth factor (FGF2) is an angiogenic factor that appears to protect endothelial cells from different stresses. Here we evaluated the effect of FGF2 on endothelial cells treated with LPS and IFN. Murine aortic endothelial cells (MAEC) were treated with LPS, IFN, FGF2 and an inhibitor of NO synthase, L‐NAME. The effect of treatment volume on iNOS induction was also determined. iNOS mRNA and protein were measured by RT‐PCR and western blotting. Cell injury was assessed by phase–contrast microscopy. LPS (10 ug/mL) plus IFN (20 ng/mL) synergistically increased iNOS mRNA and protein in MAEC, and minimal cell injury was detected. Remarkably, addition of FGF2 to LPS and IFN increased iNOS protein, in a dose‐dependent manner, up to another factor of 10. When the volume of treatment with FGF2, LPS and IFN was increased from 2 ml to 10 ml, this high induction of iNOS was reduced by 80%. The combination of FGF2 (5 ng/mL) with LPS and IFN caused cell loss (37‐fold increase in culture area devoid of cells) after 120 h, which was prevented by pre‐incubation with L‐NAME. The results suggest that, rather than protecting MAEC, FGF2 increased injury of cells treated with LPS and IFN. FGF2 also enhanced the induction of iNOS by LPS plus IFN, and facilitated cell injury by an iNOS‐dependent mechanism that may involve an autocrine factor.