Inhibition of plaque neovascularization reduces macrophage accumulation and progression of advanced atherosclerosis.
Plaque angiogenesis promotes the growth of atheromas, but the functions of plaque capillaries are not fully determined. Neovascularization may act as a conduit for the entry of leukocytes into sites of chronic inflammation. We observe vasa vasorum density correlates highly with the extent of inflammatory cells, not the size of atheromas in apolipoprotein E-deficient mice. We show atherosclerotic aortas contain activities that promote angiogenesis. The angiogenesis inhibitor angiostatin reduces plaque angiogenesis and inhibits atherosclerosis. Macrophages in the plaque and around vasa vasorum are reduced, but we detect no direct effect of angiostatin on monocytes. After angiogenesis blockade in vivo, the angiogenic potential of atherosclerotic tissue is suppressed. Activated macrophages stimulate angiogenesis that can further recruit inflammatory cells and more angiogenesis. Our findings demonstrate that late-stage inhibition of angiogenesis can interrupt this positive feedback cycle. Inhibition of plaque angiogenesis and the secondary reduction of macrophages may have beneficial effects on plaque stability.
Moulton
Karen S
KS
Department of Surgery, Children's Hospital Medical Center and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA. karen.moulton@tch.harvard.edu
Vakili
Khashayar
K
Zurakowski
David
D
Soliman
Mohsin
M
Butterfield
Catherine
C
Sylvin
Erik
E
Lo
Kin-Ming
KM
Gillies
Stephen
S
Javaherian
Kashi
K
Folkman
Judah
J
D043168:Angiostatins; D000818:Animals; D001057:Apolipoproteins E / Q000172:deficiency / Q000235:genetics; D001161:Arteriosclerosis / Q000209:etiology / Q000473:pathology* / Q000517:prevention & control*; D018932:Chemokine CCL2 / Q000096:biosynthesis; D016228:Endothelial Growth Factors / Q000096:biosynthesis / Q000494:pharmacology; D005246:Feedback; D066298:In Vitro Techniques; D007249:Inflammation / Q000473:pathology; D036341:Intercellular Signaling Peptides and Proteins / Q000096:biosynthesis / Q000494:pharmacology; D008222:Lymphokines / Q000096:biosynthesis / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000473:pathology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009000:Monocytes / Q000187:drug effects / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000517:prevention & control*; D010446:Peptide Fragments / Q000096:biosynthesis / Q000494:pharmacology; D010958:Plasminogen / Q000096:biosynthesis / Q000494:pharmacology; D011973:Receptors, LDL / Q000172:deficiency / Q000235:genetics; D014651:Vasa Vasorum / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D001057:Apolipoproteins E; D018932:Chemokine CCL2; D016228:Endothelial Growth Factors; D036341:Intercellular Signaling Peptides and Proteins; D008222:Lymphokines; D010446:Peptide Fragments; D011973:Receptors, LDL; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D043168:Angiostatins; D010958:Plasminogen