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- Bräsen, Jan Hinrich, et al.
(author)
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Extracellular superoxide dismutase accelerates endothelial recovery and inhibits in-stent restenosis in stented atherosclerotic Watanabe heritable hyperlipidemic rabbit aorta
- 2007
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In: Journal of the American College of Cardiology. - : Elsevier BV. - 0735-1097 .- 1558-3597. ; 50:23, s. 2249-2253
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Journal article (peer-reviewed)abstract
- This study examined whether local gene therapy with extracellular superoxide dismutase (EC-SOD) could inhibit in-stent restenosis in atherosclerotic Watanabe heritable hyperlipidemic rabbits. Background Stenting causes an acute increase in superoxide anion production and oxidative stress; EC-SOD is a major component of antioxidative defense in blood vessels and has powerful cardioprotective effects in ischemic myocardium. Methods Endothelial denudation and stenting were done in 36 adult (15 to 18 months old) rabbits. Catheter-mediated intramural delivery of clinical good manufacturing practice-grade adenoviruses encoding rabbit EC-SOD were done simultaneously with stenting. Control animals received adenovirus-encoding nuclear-targeted β-galactosidase (AdLacZ). Circulating markers for oxidative stress (nonesterified 8-iso-prostaglandin F2 alpha) were measured. Analysis of 6-day, 28-day, and 90-day vessel histology, radical production, oxidation-specific epitopes, and expression studies were performed. Results The EC-SOD treatment reduced oxidant production in stented vessels compared with control vessels. Early systemic recovery of total SOD activity was observed in the treated rabbits. The EC-SOD significantly accelerated endothelial recovery (67.4% ± 10.8% vs. 24.2.1% ± 4.6% at 6 days, p < 0.05; 89.3% ± 3.7% vs. 45.1% ± 9.6% at 28 days, p < 0.05), and the beneficial effect involved increased proliferation of regenerating endothelium. The EC-SOD group showed a 61.3% lower (p < 0.05) neointimal formation at 28 days, with a similar, albeit nonsignificant trend at 90 days (1.20 ± 0.32 mm2 vs. 1.88 ± 0.24 mm2, p = 0.06). Conclusions The results suggest a central pathogenetic role of oxidation sensitive signaling processes in endothelial recovery and developing in-stent restenosis in atherosclerotic vessels. Local therapy against oxidative stress represents a promising therapeutic strategy in stent-induced vascular injury. Extracellular Superoxide Dismutase Accelerates Endothelial Recovery and Inhibits In-Stent Restenosis in Stented Atherosclerotic Watanabe Heritable Hyperlipidemic Rabbit Aorta Jan Hinrich Bräsen, Olli Leppänen, Matias Inkala, Tommi Heikura, Max Levin, Fabian Ahrens, Juha Rutanen, Hubertus Pietsch, David Bergqvist, Anna-Liisa Levonen, Samar Basu, Thomas Zeller, Günter Klöppel, Mikko O. Laukkanen, Seppo Ylä-Herttuala Percutaneous coronary interventions induce oxidative stress in vessels that already have compromised antioxidative defenses. Extracellular superoxide dismutase (EC-SOD) is a major antioxidant in healthy arteries, and exogenous EC-SOD confers powerful vasculoprotective and cardioprotective effects. However, the effects of EC-SOD therapy on stent-induced vascular injury have not been assessed. We present evidence showing that local therapy with EC-SOD, delivered using clinical-grade adenoviruses, attenuated tissue oxidant production, suppressed developing in-stent restenosis, and accelerated endothelial recovery.
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| 2. |
- Karpanen, Terhi, et al.
(author)
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Lymphangiogenic growth factor responsiveness is modulated by postnatal lymphatic vessel maturation.
- 2006
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In: American Journal of Pathology. - : Elsevier BV. - 0002-9440 .- 1525-2191. ; 169:2
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Journal article (peer-reviewed)abstract
- Lymphatic vessel plasticity and stability are of considerable importance when attempting to treat diseases associated with the lymphatic vasculature. Development of lymphatic vessels during embryogenesis is dependent on vascular endothelial growth factor (VEGF)-C but not VEGF-D. Using a recombinant adenovirus encoding a soluble form of their receptor VEGFR-3 (AdVEGFR-3-Ig), we studied lymphatic vessel dependency on VEGF-C and VEGF-D induced VEGFR-3 signaling in postnatal and adult mice. Transduction with AdVEGFR-3-Ig led to regression of lymphatic capillaries and medium-sized lymphatic vessels in mice under 2 weeks of age without affecting collecting lymphatic vessels or the blood vasculature. No effect was observed after this period. The lymphatic capillaries of neonatal mice also regressed partially in response to recombinant VEGFR-3-Ig or blocking antibodies against VEGFR-3, but not to adenovirus-encoded VEGFR-2-Ig. Despite sustained inhibitory VEGFR-3-Ig levels, lymphatic vessel regrowth was observed at 4 weeks of age. Interestingly, whereas transgenic expression of VEGF-C in the skin induced lymphatic hyperplasia even during embryogenesis, similar expression of VEGF-D resulted in lymphangiogenesis predominantly after birth. These results indicate considerable plasticity of lymphatic vessels during the early postnatal period but not thereafter, suggesting that anti-lymphangiogenic therapy can be safely applied in adults.
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| 3. |
- Karpanen, Terhi, et al.
(author)
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Overexpression of vascular endothelial growth factor-B in mouse heart alters cardiac lipid metabolism and induces myocardial hypertrophy
- 2008
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In: Circulation Research. - : American Heart Association. - 0009-7330 .- 1524-4571. ; 103:9, s. 1018-1026
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Journal article (peer-reviewed)abstract
- Vascular endothelial growth factor (VEGF)-B is poorly angiogenic but prominently expressed in metabolically highly active tissues, including the heart. We produced mice expressing a cardiac-specific VEGF-B transgene via the alpha-myosin heavy chain promoter. Surprisingly, the hearts of the VEGF-B transgenic mice showed concentric cardiac hypertrophy without significant changes in heart function. The cardiac hypertrophy was attributable to an increased size of the cardiomyocytes. Blood capillary size was increased, whereas the number of blood vessels per cell nucleus remained unchanged. Despite the cardiac hypertrophy, the transgenic mice had lower heart rate and blood pressure than their littermates, and they responded similarly to angiotensin II-induced hypertension, confirming that the hypertrophy does not compromise heart function. Interestingly, the isolated transgenic hearts had less cardiomyocyte damage after ischemia. Significantly increased ceramide and decreased triglyceride levels were found in the transgenic hearts. This was associated with structural changes and eventual lysis of mitochondria, resulting in accumulation of intracellular vacuoles in cardiomyocytes and increased death of the transgenic mice, apparently because of mitochondrial lipotoxicity in the heart. These results suggest that VEGF-B regulates lipid metabolism, an unexpected function for an angiogenic growth factor.
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| 4. |
- Tammela, Tuomas, et al.
(author)
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Blocking VEGFR-3 suppresses angiogenic sprouting and vascular network formation.
- 2008
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In: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 454:7204, s. 656-60
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Journal article (peer-reviewed)abstract
- Angiogenesis, the growth of new blood vessels from pre-existing vasculature, is a key process in several pathological conditions, including tumour growth and age-related macular degeneration. Vascular endothelial growth factors (VEGFs) stimulate angiogenesis and lymphangiogenesis by activating VEGF receptor (VEGFR) tyrosine kinases in endothelial cells. VEGFR-3 (also known as FLT-4) is present in all endothelia during development, and in the adult it becomes restricted to the lymphatic endothelium. However, VEGFR-3 is upregulated in the microvasculature of tumours and wounds. Here we demonstrate that VEGFR-3 is highly expressed in angiogenic sprouts, and genetic targeting of VEGFR-3 or blocking of VEGFR-3 signalling with monoclonal antibodies results in decreased sprouting, vascular density, vessel branching and endothelial cell proliferation in mouse angiogenesis models. Stimulation of VEGFR-3 augmented VEGF-induced angiogenesis and sustained angiogenesis even in the presence of VEGFR-2 (also known as KDR or FLK-1) inhibitors, whereas antibodies against VEGFR-3 and VEGFR-2 in combination resulted in additive inhibition of angiogenesis and tumour growth. Furthermore, genetic or pharmacological disruption of the Notch signalling pathway led to widespread endothelial VEGFR-3 expression and excessive sprouting, which was inhibited by blocking VEGFR-3 signals. Our results implicate VEGFR-3 as a regulator of vascular network formation. Targeting VEGFR-3 may provide additional efficacy for anti-angiogenic therapies, especially towards vessels that are resistant to VEGF or VEGFR-2 inhibitors.
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