Angiotensin II angiogenic effect in vivo involves vascular endothelial growth factor- and inflammation-related pathways.
Although accumulating lines of evidence indicate the proangiogenic role of angiotensin II (Ang II), little is known about the molecular mechanisms associated with such an effect. This study aimed to identify molecular events involved in Ang II-induced angiogenesis in the Matrigel model in mice. C57Bl/6 female mice received a subcutaneous injection of either Matrigel or Matrigel with Ang II (10(-7) M) alone, with Ang II and an AT1 receptor antagonist (candesartan, 10(-6) M), or with Ang II and AT2 receptor antagonist (PD123319, 10(-6) M). After 14 days, angiogenesis was assessed in the Matrigel-plug by histological evaluation and cellular counting. Ang II increased by 1.9-fold the number of cells within the Matrigel (p < 0.01 versus control). Immunohistological analysis revealed the presence of macrophages, endothelial and smooth muscle cells, and the development of vascular-like structure. Such an angiogenic effect was associated with an increase in vascular endothelial growth factor (VEGF) (1.5-fold, p < 0.01), endothelial nitric oxide (eNOS) (1.7-fold, p < 0.01), and cyclooxygenase-2 (1.4-fold, p < 0.05) protein levels measured by Western blotting. Conversely, Ang II treatment did not affect MMP-9 and MMP-2 activity, assessed by zymography. Blockade of AT1 receptor completely prevented the Ang II-induced angiogenesis and protein regulations, whereas that of AT2 was ineffective. Administration of VEGF neutralizing antibody (2.5 microg ip twice a week) and cyclooxygenase-2 selective inhibitor (nimesulide, 30 mg/L) also hampered Ang II proangiogenic effect. In addition, Ang II-induced cell ingrowth was impaired by treatment with nitric oxide synthase inhibitor (L-NAME, 10 mg/kg/day) and in eNOS-deficient mice. Therefore, in an in vivo model, Ang II induced angiogenesis through AT1 receptor, which involved activation of VEGF/eNOS-related pathway and of the inflammatory process.
Tamarat
Radia
R
INSERM U541, Hôpital Lariboisière, IFR Circulation-Paris 7, Université Paris 7-Denis Diderot, Paris, France.
Silvestre
Jean-Sébastien
JS
Durie
Micheline
M
Levy
Bernard I
BI
D000804:Angiotensin II / Q000378:metabolism* / Q000627:therapeutic use*; D057911:Angiotensin Receptor Antagonists; D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D001562:Benzimidazoles / Q000494:pharmacology; D001713:Biphenyl Compounds; D003094:Collagen / Q000494:pharmacology; D051546:Cyclooxygenase 2; D004195:Disease Models, Animal; D004338:Drug Combinations; D004359:Drug Therapy, Combination; D016228:Endothelial Growth Factors / Q000276:immunology / Q000378:metabolism*; D005260:Female; D007093:Imidazoles / Q000494:pharmacology; D007527:Isoenzymes / Q000378:metabolism; D007797:Laminin / Q000494:pharmacology; D008222:Lymphokines / Q000276:immunology / Q000378:metabolism*; D008264:Macrophages / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009389:Neovascularization, Pathologic / Q000139:chemically induced / Q000188:drug therapy*; D019001:Nitric Oxide Synthase / Q000172:deficiency / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D011509:Proteoglycans / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D044140:Receptor, Angiotensin, Type 1; D011945:Receptors, Angiotensin / Q000378:metabolism; D013449:Sulfonamides / Q000494:pharmacology; D013777:Tetrazoles / Q000494:pharmacology; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D057911:Angiotensin Receptor Antagonists; D000911:Antibodies, Monoclonal; D001562:Benzimidazoles; D001713:Biphenyl Compounds; D004338:Drug Combinations; D016228:Endothelial Growth Factors; D007093:Imidazoles; D007527:Isoenzymes; D007797:Laminin; D008222:Lymphokines; D011509:Proteoglycans; D011725:Pyridines; D044140:Receptor, Angiotensin, Type 1; D011945:Receptors, Angiotensin; D013449:Sulfonamides; D013777:Tetrazoles; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D000804:Angiotensin II; C059485:matrigel; C073402:PD 123319; D003094:Collagen; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496315:Nos3 protein, mouse; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; C081643:candesartan; C012655:nimesulide; D019331:NG-Nitroarginine Methyl Ester