Neovascularization is associated with atherosclerosis and the vasa vasorum is the primary source of angiogenic vessels that supply the neovascularized area. There is evidence that vasa vasorum density increases during plaque progression, but it remains uncertain that angiogenesis has a major role in atherosclerotic plaque growth. We have shown that a truncated plasminogen activator inhibitor-1 (PAI-1) protein, rPAI-123, has significant anti-angiogenic activity. Studies performed in this funding period show that rPAI-123 inhibits fibroblast growth factor-2 (FGF2) signaling pathways and functions. We hypothesized that rPAI-123 would inhibit angiogenic vasa vasorum in atherogenic mice to result in reduced plaque progression. The hypothesis was tested in female LDLR-/-/ ApoB-100 mice that received a high fat diet for 14 weeks prior to initiating 6 weeks of rPAI-123 (n=16) or saline (n=11) treatment with continued high fat diet. Seven control animals received normal chow diet and saline treatment. The ratio of lipid area: total area in Sudan 4 stained vessels was 60% (p< 0.001) less in the descending aorta and 30% (p<0.001) less in the aortic root of rPAI-123 treated animals when compared to high fat, saline treated mice. Reconstructed confocal microscopy images of CD31- probed vessels in the plaque area show that rPAI-123 reduced vessel area and length by 43 and 37% (p = 0.01), respectively when compared to high fat, saline treated controls. The left carotid artery circumference in high fat, rPAI-123 and high fat, saline groups were 24% (p=0.05) greater than the chow fed control. However, treatment with rPAI-123 reduced plaque area by 67% (p<0.001) and increased lumen area by 74% (p<0.001) when compared to the high fat, saline group. These data strongly support our hypothesis and additionally suggest that rPAI-123 promotes plaque regression. This proposal will further examine plaque regression in response to rPAI-123 in atherogenic female LDLR-/-/ ApoB-100 mice. Opposing effects of rPAI-123 on native PAI-1 functions will be studied in PAI-1-/-/ LDLR-/-/ ApoB-100. Finally, rPAI-123 binding interactions with potential candidate receptors will be investigated. Current medical treatment for atherosclerotic disease potentially prevents progression. A molecule that promotes plaque regression would provide profound medical advancement, thus making the proposed studies highly significant. Atherosclerosis is a prevalent vascular disease among Americans and is a leading cause of death. We have produced a truncated PAI-1 protein, rPAI-123, that has significant anti-angiogenic activity. Our preliminary results with rPAI-123 are novel, demonstrating for the first time that a modified PAI-1 protein can inhibit angiogenic vessels in a mouse model of atherosclerosis and promote plaque regression. These observations raise the possibility that rPAI-123 may ultimately have a therapeutic role in atherosclerosis. Current medical treatment for atherosclerotic disease potentially prevents progression, therefore, a molecule that promotes plaque regression would provide profound medical advancement, thus making the proposed studies highly significant. ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
2R01HL069948-05A2
Application #
7390517
Study Section
Bioengineering, Technology and Surgical Sciences Study Section (BTSS)
Program Officer
Link, Rebecca P
Project Start
2002-04-01
Project End
2011-11-30
Budget Start
2007-12-21
Budget End
2008-11-30
Support Year
5
Fiscal Year
2008
Total Cost
$359,775
Indirect Cost
Name
Dartmouth College
Department
Surgery
Type
Schools of Medicine
DUNS #
041027822
City
Hanover
State
NH
Country
United States
Zip Code
03755
Baeyens, Nicolas; Mulligan-Kehoe, Mary Jo; Corti, Federico et al. (2014) Syndecan 4 is required for endothelial alignment in flow and atheroprotective signaling. Proc Natl Acad Sci U S A 111:17308-13
Mulligan-Kehoe, Mary Jo (2013) Anti-angiogenic activity of rPAI-1(23) and vasa vasorum regression. Trends Cardiovasc Med 23:114-20
Robbins, Clinton S; Chudnovskiy, Aleksey; Rauch, Philipp J et al. (2012) Extramedullary hematopoiesis generates Ly-6C(high) monocytes that infiltrate atherosclerotic lesions. Circulation 125:364-74
Mollmark, Jessica I; Park, Andrew J-H; Kim, Justin et al. (2012) Fibroblast growth factor-2 is required for vasa vasorum plexus stability in hypercholesterolemic mice. Arterioscler Thromb Vasc Biol 32:2644-51
Mollmark, Jessica; Ravi, Saranya; Sun, Baiming et al. (2011) Antiangiogenic activity of rPAI-1(23) promotes vasa vasorum regression in hypercholesterolemic mice through a plasmin-dependent mechanism. Circ Res 108:1419-28
Zagorchev, L; Mulligan-Kehoe, M J (2011) Advances in imaging angiogenesis and inflammation in atherosclerosis. Thromb Haemost 105:820-7
Zagorchev, Lyubomir; Oses, Pierre; Zhuang, Zhen W et al. (2010) Micro computed tomography for vascular exploration. J Angiogenes Res 2:7
Mulligan-Kehoe, Mary Jo (2010) The vasa vasorum in diseased and nondiseased arteries. Am J Physiol Heart Circ Physiol 298:H295-305
Ren, Bin; Deng, Yong; Mukhopadhyay, Arpita et al. (2010) ERK1/2-Akt1 crosstalk regulates arteriogenesis in mice and zebrafish. J Clin Invest 120:1217-28
Drinane, Mary; Mollmark, Jessica; Zagorchev, Lyubomir et al. (2009) The antiangiogenic activity of rPAI-1(23) inhibits vasa vasorum and growth of atherosclerotic plaque. Circ Res 104:337-45

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