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Sata M. Molecular strategies to treat vascular diseases: circulating vascular progenitor cell as a potential target for prophylactic treatment of atherosclerosis. Circ J 2004; 67:983-91. [PMID: 14639011 DOI: 10.1253/circj.67.983] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Atherosclerosis is responsible for more than half of all deaths in Western countries. Numerous studies have reported that accumulation of smooth muscle cells (SMCs) plays a principal role in atherogenesis, post-angioplasty restenosis and transplantation-associated vasculopathy. Although much effort has been devoted to targeting the migration and proliferation of medial SMCs, effective therapy to prevent occlusive vascular remodeling has not been established. Recently, it was suggested that bone marrow-derived precursors can give rise to vascular cells that contribute to the repair, remodeling, and lesion formation of the arterial wall under certain circumstances. This review highlights the recent findings on circulating vascular precursors and describes the potential therapeutic strategies for vascular diseases, targeting mobilization, homing, differentiation and proliferation of circulating progenitor cells.
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Affiliation(s)
- Masataka Sata
- Department of Cardiovascular Medicine, University of Tokyo Graduate School of Medicine, Tokyo and PRESTO, Japan Science and Technology Agency, Kawaguchi.
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52
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Wan S, George SJ, Nicklin SA, Yim APC, Baker AH. Overexpression of p53 Increases Lumen Size and Blocks Neointima Formation in Porcine Interposition Vein Grafts. Mol Ther 2004; 9:689-98. [PMID: 15120330 DOI: 10.1016/j.ymthe.2004.02.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2003] [Accepted: 02/01/2004] [Indexed: 11/20/2022] Open
Abstract
Patency rates for autologous saphenous vein (SV) conduits used in coronary artery bypass grafts remain poor. Patients with failed grafts are difficult to treat with subsequent interventions, necessitating the development of innovative therapies. Previous studies have suggested that induction of smooth muscle cell (SMC) apoptosis may reduce neointima formation. We overexpressed the proapoptotic gene p53 at the lumenal surface of SV grafts using adenoviral (Ad)-mediated gene transfer in porcine SVs prior to grafting in vivo and analyzed at 7 and 28 days (n = 6 and 7 per group, respectively). p53 overexpression induced a significant upregulation in apoptosis (4 +/- 0.6% for Adp53-infected grafts vs 0.6 +/- 0.1% for Adbeta-gal-infected grafts) and reduced neointimal proliferation by 28 +/- 1% at day 7 postinfection. Adp53-infected grafts had significantly greater lumenal areas than controls at both time points (4.8 +/- 0.6 mm2 vs 2.9 +/- 0.5 mm2 and 10.0 +/- 2.5 mm2 vs 4.2 +/- 1.2 mm2 at 7 and 28 days, respectively). Total graft areas were also increased at 28 days by p53, indicating positive vessel remodeling. Additionally, the thickening of the neointima was significantly reduced by 68 +/- 22% and 28 +/- 3% by p53 overexpression at day 7 and 28, respectively. Importantly, phenotypic changes were maintained at 3 months. Induction of SMC apoptosis by transient p53 overexpression positively influenced vein graft remodeling.
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Affiliation(s)
- Song Wan
- Division of Cardiothoracic Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, NT, Hong Kong
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53
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Raymond MA, Désormeaux A, Laplante P, Vigneault N, Filep JG, Landry K, Pshezhetsky AV, Hébert MJ. Apoptosis of endothelial cells triggers a caspase‐dependent anti‐apoptotic paracrine loop active on vascular smooth muscle cells. FASEB J 2004; 18:705-7. [PMID: 14977881 DOI: 10.1096/fj.03-0573fje] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Increased endothelial apoptosis and decreased apoptosis of vascular smooth muscle cells (VSMC) are central to initiation of myo-intimal thickening. We hypothesized that apoptosis of endothelial cells (EC) induces the release of anti-apoptotic mediator(s) active on VSMC. We found that serum-free medium conditioned by apoptotic EC decreases apoptosis of VSMC compared with fresh serum-free medium. Inhibition of endothelial apoptosis during conditioning with a pan-caspase inhibitor ZVAD-FMK blocked the release of the anti-apoptotic factor(s) active on VSMC. VSMC exposed to serum-free medium conditioned by apoptotic EC showed increased ERK 1/2 phosphorylation, enhanced Bcl-xl expression, and inhibition of p53 expression. Fractionation of the conditioned medium followed by mass spectral analysis identified one bioactive component as a C-terminal fragment of the domain V of perlecan. Serum-free medium supplemented with either a synthetic peptide containing the EGF motif of the domain V of perlecan or chondroitin 4-sulfate, a glycosaminoglycan anchored on the domain V of perlecan, increased ERK 1/2 phosphorylation and Bcl-xl protein levels while inhibiting apoptosis of VSMC. These results suggest that a proteolytic activity developing downstream of activated caspases in apoptotic EC initiates degradation of pericellular proteoglycans and liberation of bioactive fragments with a robust impact on inhibition of VSMC apoptosis.
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54
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Sata M, Tanaka K, Ishizaka N, Hirata Y, Nagai R. Absence of p53 leads to accelerated neointimal hyperplasia after vascular injury. Arterioscler Thromb Vasc Biol 2003; 23:1548-52. [PMID: 12893686 DOI: 10.1161/01.atv.0000089327.48154.32] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE It has been suggested that deregulated expression of the tumor suppressor protein p53 may play a role in the pathogenesis of occlusive vascular remodeling. However, the role of p53 in cell proliferation and apoptosis in vascular lesions has been controversial. METHODS AND RESULTS We tested the potential involvement of p53-mediated molecular signaling in lesion formation using a mouse model of vascular injury that may resemble balloon angioplasty. A large wire was inserted into the femoral artery of p53+/+ and p53-/- mice. There was no significant difference in the occurrence of rapid-onset apoptosis, that is, 4 hours after injury. At 2 weeks, the number of proliferating cells in the lesion of p53-/- mice was significantly higher than that observed in p53+/+ mice. The frequency of apoptotic cells was significantly lower in p53-/- mice than in p53+/+ mice. At 4 weeks, the neointimal hyperplasia of p53-/- mice was greater than that of p53+/+ mice. There was no significant difference in the frequency of apoptosis in the lesions. CONCLUSIONS These results indicate a crucial role of p53 in pathological vascular remodeling after mechanical injury and provide the basis for the development of new therapies targeting p53 for a prophylactic treatment of vascular diseases.
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Affiliation(s)
- Masataka Sata
- Department of Cardiovascular Medicine, University of Tokyo Graduate School of Medicine, Japan.
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55
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Uglow EB, Slater S, Sala-Newby GB, Aguilera-Garcia CM, Angelini GD, Newby AC, George SJ. Dismantling of cadherin-mediated cell-cell contacts modulates smooth muscle cell proliferation. Circ Res 2003; 92:1314-21. [PMID: 12775583 DOI: 10.1161/01.res.0000079027.44309.53] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Proliferation of vascular smooth muscle cells (VSMCs) contributes to intimal thickening during atherosclerosis and restenosis. The cadherins are transmembrane proteins, which form cell-cell contacts and may regulate VSMC proliferation. In this study, N-cadherin protein concentration was significantly reduced by stimulation of proliferation with fetal calf serum (FCS) and platelet-derived growth factor-BB (PDGF-BB) in human saphenous vein VSMCs. Furthermore, overexpression of a truncated N-cadherin, which acts as a dominant-negative increased VSMC proliferation. The amount of an extracellular fragment of N-cadherin (approximately 90 kDa) in the media after 24 hours was increased by 12-fold by FCS and 11-fold by PDGF-BB, suggesting that N-cadherin levels are regulated by proteolytic shedding. Incubation with a synthetic metalloproteinase inhibitor or adenoviral overexpression of the endogenous tissue inhibitors of metalloproteinases (TIMPs) demonstrated that metalloproteinase activity was responsible in part for this proteolysis. Although total levels of beta-catenin protein were not affected, beta-catenin was translocated to the nucleus after stimulation with FCS and PDGF-BB. Our data indicates cadherin-mediated cell-cell contacts modulate proliferation in VSMCs. Furthermore, disruption of N-cadherin cell-cell contacts mediated in part by metalloproteinase activity occurs during VSMC proliferation, releasing beta-catenin and possibly inducing beta-catenin-mediated intracellular signaling.
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Affiliation(s)
- Elizabeth B Uglow
- Bristol Heart Institute, Level 7, Bristol Royal Infirmary, Bristol, BS2 8HW, UK
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56
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Abstract
The last decade has seen substantial advances in the development of gene therapy strategies and vector technology for the treatment of a diverse number of diseases, with a view to translating the successes observed in animal models into the clinic. Perhaps the overwhelming drive for the increase in vascular gene transfer studies is the current lack of successful long-term pharmacological treatments for complex cardiovascular diseases. The increase in cardiovascular disease to epidemic proportions has also led many to conclude that drug therapy may have reached a plateau in its efficacy and that gene therapy may represent a realistic solution to a long-term problem. Here, we discuss gene delivery approaches and target diseases.
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Affiliation(s)
- Kate L. Dishart
- BHF Blood Pressure Group, Department of Medicine and Therapeutics,
University of Glasgow, Western Infirmary, Glasgow G11 6NT, UK
| | - Lorraine M. Work
- BHF Blood Pressure Group, Department of Medicine and Therapeutics,
University of Glasgow, Western Infirmary, Glasgow G11 6NT, UK
| | - Laura Denby
- BHF Blood Pressure Group, Department of Medicine and Therapeutics,
University of Glasgow, Western Infirmary, Glasgow G11 6NT, UK
| | - Andrew H. Baker
- BHF Blood Pressure Group, Department of Medicine and Therapeutics,
University of Glasgow, Western Infirmary, Glasgow G11 6NT, UK
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57
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Abstract
Cigarette smoking as an addictive habit has accompanied human beings for more than 4 centuries. It is also one of the most potent and prevalent environmental health risks human beings are exposed to, and it is responsible for more than 1000 deaths each day in the United States. With recent research progress, it becomes clear that cigarette smoking can cause almost all major diseases prevalent today, such as cancer or heart disease. These detrimental effects are not only present in active smokers who choose the risk, but also to innocent bystanders, as passive smokers, who are exposed to cigarettes not-by-choice. While the cigarette-induced harm to human health is indiscriminate and severe, the degree of damage also varies from individual to individual. This intersubject variability in cigarette-induced pathologies is partly mediated by genetic variants of genes that may participate in detoxification process, eg, cytochrome P450 (CYP), cellular susceptibility to toxins, such as p53, or disease development. Through population studies, we have learned that certain CYP1A1 variants, such as Mspl polymorphism, may render the carriers more susceptible to cigarette-induced lung cancer or severe coronary atherosclerosis. The endothelial nitric oxide synthase intron 4 rare allele homozygotes are more likely to have myocardial infarction if they also smoke. In vitro experimental approach has further demonstrated that cigarettes may specifically regulate these genes in genotype-dependent fashion. While we still know little about genetic basis and molecular pathways for cigarette-induced pathological changes, understanding these mechanisms will be of great value in designing strategies to further reduce smoking in targeted populations, and to implement more effective measures in prevention and treatment of cigarette-induced diseases.
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Affiliation(s)
- Xing Li Wang
- Vascular Genetics Laboratory, Department of Genetics, Southwest Foundation for Biomedical Research, San Antonio, TX 78227, USA.
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58
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Nicklin SA, Baker AH. Development of targeted viral vectors for cardiovascular gene therapy. GENETIC ENGINEERING 2003; 25:15-49. [PMID: 15260232 DOI: 10.1007/978-1-4615-0073-5_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Affiliation(s)
- Stuart A Nicklin
- British Heart Foundation Blood Pressure Group, Division of Cardiovascular and Medical Sciences, University of Glasgow, Western Infirmary, Glasgow G11 6NT, UK
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59
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Taurin S, Seyrantepe V, Orlov SN, Tremblay TL, Thibault P, Bennett MR, Hamet P, Pshezhetsky AV. Proteome analysis and functional expression identify mortalin as an antiapoptotic gene induced by elevation of [Na+]i/[K+]i ratio in cultured vascular smooth muscle cells. Circ Res 2002; 91:915-22. [PMID: 12433836 DOI: 10.1161/01.res.0000043020.45534.3e] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Apoptosis of vascular smooth muscle cells (VSMCs) plays an important role in remodeling of vessel walls, one of the major determinants of long-term blood pressure elevation and an independent risk factor for cardiovascular morbidity and mortality. Recently, we have found that apoptosis in cultured VSMCs can be inhibited by inversion of the intracellular [Na+]/[K+] ratio after the sustained blockage of the Na+,K+-ATPase by ouabain. To understand the mechanism of ouabain action, we analyzed subsets of hydrophilic and hydrophobic VSMC proteins from control and ouabain-treated cells by 2-dimensional electrophoresis. Ouabain treatment led to overexpression of numerous soluble and hydrophobic cellular proteins. Among proteins that showed the highest level of ouabain-induced expression, we identified mortalin (also known as GRP75 or PBP-74), a member of the heat shock protein 70 (HSP70) superfamily and a marker for cellular mortal and immortal phenotypes. Northern and Western blotting and immunocytochemistry all have confirmed that treatment of VSMCs with ouabain results in potent induction of mortalin expression. Transient transfection of cells with mortalin cDNA led to at least a 6-hour delay in the development of apoptosis after serum deprivation. The expression of tumor suppressor gene, p53, in mortalin-transfected cells was delayed to the same extent, and the expressed protein showed abnormal perinuclear distribution, suggesting that p53 is retained and inactivated by mortalin. Our studies therefore define a new [Na+]i/[K+]i-responsive signaling pathway that may play an important role in the regulation of programmed cell death in VSMCs.
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MESH Headings
- Animals
- Apoptosis/genetics
- Blotting, Northern
- Cells, Cultured
- Electrophoresis, Gel, Two-Dimensional
- Gene Expression Regulation/physiology
- HSP70 Heat-Shock Proteins/biosynthesis
- HSP70 Heat-Shock Proteins/genetics
- HSP70 Heat-Shock Proteins/metabolism
- Male
- Mass Spectrometry
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Ouabain/pharmacology
- Potassium/metabolism
- Proteome/chemistry
- Proteome/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred BN
- Signal Transduction/drug effects
- Signal Transduction/physiology
- Sodium/metabolism
- Sodium-Potassium-Exchanging ATPase/antagonists & inhibitors
- Transfection
- Tumor Suppressor Protein p53/antagonists & inhibitors
- Tumor Suppressor Protein p53/metabolism
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Affiliation(s)
- Sebastien Taurin
- Centre de Recherche de l'Hôpital Sainte Justine, Montréal, Québec, Canada
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60
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Abstract
Gene therapy could improve human saphenous vein (HSV) coronary vein-graft patency by reducing early thrombosis, neointimal hyperplasia and atherosclerosis. Mouse and rabbit models use veins with much thinner walls than pig or HSVs but atherosclerosis can be more easily induced; none of these models shows early thrombosis. Prostacyclin synthase, tissue factor pathway inhibitor, and tissue plasminogen activator might decrease thrombus formation. Tissue inhibitors of metalloproteinases (TIMPs) reduce intimal migration of smooth muscle cells, while TIMP-3 and the p53 tumor suppressor protein promote apoptosis. Prostacyclin synthase and nitric oxide synthase, and cell cycle inhibitors, such as E2F decoy oligonucleotides (D-E2F), reduce neointima formation. This might be enough by itself to decrease later atherosclerosis. Alternatively, direct targeting with nitric oxide synthase, decoy adhesion molecules, or interleukin-10 might be possible.
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Affiliation(s)
- Stephen J White
- Bristol Heart Institute, University of Bristol, Bristol Royal Infirmary, Bristol, UK
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61
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Abstract
PURPOSE OF REVIEW Rupture of an atherosclerotic plaque is the predominant underlying event in the pathogenesis of acute coronary syndromes and stroke. While ruptured plaques are morphologically well described, the precise molecular mechanisms involved in plaque rupture are still incompletely understood. Over the last few years, techniques like microarray, suppression subtractive hybridization and differential display enabled us to study complex gene expression profiles that occur during the process of atherogenesis. In this review we focus on recent large-scale gene expression profiles performed on whole mount vascular specimens. RECENT FINDINGS The gene expression profiles on whole mount vascular tissue confirmed that at least three mechanisms are involved in plaque rupture: (1) a disturbed balance in extracellular matrix turnover, (2) disturbed regulation of cell turnover and (3) processes involved in lipid metabolism. Animal models exhibiting features of plaque rupture reflect the involvement of these three mechanisms. The most dramatic mouse phenotypes were observed after interventions in at least two of these mechanisms. SUMMARY The observation of plaque rupture in recent mice models is indicative of the multifactorial process of plaque rupture. This multifactorial character of plaque rupture suggests that interventions may be most effective when they influence more than one mechanisms at a time.
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Affiliation(s)
- Birgit C G Faber
- Department of Pathology, Cardiovascvular Research Institute Maastricht (CARIM), University of Maastricht, 6200 MD Maastricht, The Netherlands
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62
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Mayr U, Mayr M, Li C, Wernig F, Dietrich H, Hu Y, Xu Q. Loss of p53 accelerates neointimal lesions of vein bypass grafts in mice. Circ Res 2002; 90:197-204. [PMID: 11834713 DOI: 10.1161/hh0202.103715] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The transcription factor p53 is essentially involved in regulation of cell death and proliferation. Recently, we have established a mouse model for vein graft arteriosclerosis by grafting autologous jugular veins or vena cava to carotid arteries. Using this model, we studied the role of p53 in the development of vein graft arteriosclerosis in p53(-/-) mice. Four weeks after grafting, neointimal hyperplasia of vein grafts in p53(-/-) mice was increased 2-fold compared with that of wild-type controls. Cell component analysis revealed that neointimal lesions in p53(-/-) mice consisted mainly of alpha-actin positive smooth muscle cells (SMCs), whereas the majority of cells in wild-type mice were MAC-1 (CD11b/18)-positive at 4 weeks. Importantly, SMC apoptosis as determined by TUNEL assay was significantly reduced in p53(-/-) vein grafts. TUNEL positive cells in wild-type vein grafts markedly increased from 0.5% to 6.4% of total cells 4 weeks postoperatively, but remained virtually unchanged in p53(-/-) grafts (0.8%). Immunofluorescence analysis revealed that increased p53 expression in neointimal SMCs of wild-type, but not p53(-/-), mice coincided with oxidative DNA damage in vein grafts. Interestingly, SMCs of p53(-/-) mice showed increased apoptosis in response to TNFalpha and decreased apoptosis in response to sodium nitroprusside. Additionally, p53-deficient SMCs showed a higher rate of proliferation and migration and expressed higher levels of matrix metalloproteinases. Thus, p53 deficiency accelerates neointima formation by facilitating SMC proliferation as well as abrogating cell apoptosis.
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MESH Headings
- Actins/biosynthesis
- Animals
- Apoptosis/drug effects
- Carotid Arteries/surgery
- Cell Division/genetics
- Cell Movement/genetics
- DNA Damage/genetics
- Disease Progression
- Genetic Predisposition to Disease
- Graft Occlusion, Vascular/etiology
- Graft Occlusion, Vascular/genetics
- Graft Occlusion, Vascular/metabolism
- Graft Occlusion, Vascular/pathology
- Heterozygote
- In Situ Nick-End Labeling
- Jugular Veins/metabolism
- Jugular Veins/pathology
- Jugular Veins/transplantation
- Macrophage-1 Antigen/biosynthesis
- Mice
- Mice, Knockout
- Mice, Mutant Strains
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Nitroprusside/pharmacology
- Oxidation-Reduction
- Transplantation, Autologous/adverse effects
- Tumor Necrosis Factor-alpha/pharmacology
- Tumor Suppressor Protein p53/deficiency
- Tumor Suppressor Protein p53/genetics
- Tumor Suppressor Protein p53/metabolism
- Vascular Surgical Procedures/adverse effects
- Veins/metabolism
- Veins/pathology
- Veins/transplantation
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Affiliation(s)
- Ursula Mayr
- Institute for Pathophysiology, University of Innsbruck, Austria
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63
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Leitges M, Mayr M, Braun U, Mayr U, Li C, Pfister G, Ghaffari-Tabrizi N, Baier G, Hu Y, Xu Q. Exacerbated vein graft arteriosclerosis in protein kinase Cδ–null mice. J Clin Invest 2001. [DOI: 10.1172/jci200112902] [Citation(s) in RCA: 200] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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64
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Leitges M, Mayr M, Braun U, Mayr U, Li C, Pfister G, Ghaffari-Tabrizi N, Baier G, Hu Y, Xu Q. Exacerbated vein graft arteriosclerosis in protein kinase Cdelta-null mice. J Clin Invest 2001; 108:1505-12. [PMID: 11714742 PMCID: PMC209416 DOI: 10.1172/jci12902] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Smooth muscle cell (SMC) accumulation is a key event in the development of atherosclerosis, including vein bypass graft arteriosclerosis. Because members of the protein kinase C (PKC) family signal cells to undergo proliferation, differentiation, or apoptosis, we generated PKCdelta knockout mice and performed vein bypass grafts on these animals. PKCdelta(-/-) mice developed normally and were fertile. Vein segments from PKCdelta(-/-) mice isografted to carotid arteries of recipient mice of either genotype led to a more severe arteriosclerosis than was seen with PKCdelta(+/+) vein grafts. Arteriosclerotic lesions in PKCdelta(-/-) mice showed a significantly higher number of SMCs than were found in wild-type animals; this was correlated with decreased SMC death in lesions of PKCdelta(-/-) mice. SMCs derived from PKCdelta(-/-) aortae were resistant to cell death induced by any of several stimuli, but they were similar to wild-type SMCs with respect to mitogen-stimulated cell proliferation in vitro. Furthermore, pro-apoptotic treatments led to diminished caspase-3 activation, poly(ADP-ribose) polymerase cleavage, and cytochrome c release in PKCdelta(-/-) relative to wild-type SMCs, suggesting that their apoptotic resistance involves the loss of free radical generation and mitochondrial dysfunction in response to stress stimuli. Our data indicate that PKCdelta maintains SMC homeostasis and that its function in the vessel wall per se is crucial in the development of vein graft arteriosclerosis.
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Affiliation(s)
- M Leitges
- Max Planck Institute for Experimental Endocrinology, Hannover, Germany
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