101
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Tölle M, Pawlak A, Schuchardt M, Kawamura A, Tietge UJ, Lorkowski S, Keul P, Assmann G, Chun J, Levkau B, van der Giet M, Nofer JR. HDL-associated lysosphingolipids inhibit NAD(P)H oxidase-dependent monocyte chemoattractant protein-1 production. Arterioscler Thromb Vasc Biol 2008; 28:1542-8. [PMID: 18483405 DOI: 10.1161/atvbaha.107.161042] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE High-density lipoprotein (HDL) levels are inversely proportional to the risk of atherosclerosis, but mechanisms of HDL atheroprotection remain unclear. Monocyte chemoatractant protein-1 (MCP-1) constitutes an early component of inflammatory response in atherosclerosis. Here we investigated the influence of HDL on MCP-1 production in vascular smooth muscle cells (VSMCs) and rat aortic explants. METHODS AND RESULTS HDL inhibited the thrombin-induced production of MCP-1 in a concentration-dependent manner. The HDL-dependent inhibition of MCP-1 production was accompanied by the suppression of reactive oxygen species (ROS), which regulate the MCP-1 production in VSMCs. HDL inhibited NAD(P)H oxidase, the preponderant source of ROS in the vasculature, and prevented the activation of Rac1, which precedes NAD(P)H-oxidase activation. The HDL capacity to inhibit MCP-1 production, ROS generation, and NAD(P)H-oxidase activation was emulated by sphingosine 1-phosphate (S1P) and sphingosylphosphorylcholine (SPC), two lysosphingolipids present in HDL, but not by apolipoprotein A-I. HDL-, S1P-, and SPC-induced inhibition of MCP-1 production was attenuated in VSMCs pretreated with VPC23019, an antagonist of lysosphingolipid receptors S1P(1) and S1P(3), but not by JTE013, an antagonist of S1P(2). In addition, HDL, S1P, and SPC failed to inhibit MCP1 production and ROS generation in aortas from S1P(3)- and SR-B1-deficient mice. CONCLUSIONS HDL-associated lysosphingolipids inhibit NAD(P)H oxidase-dependent ROS generation and MCP-1 production in a process that requires coordinate signaling through S1P(3) and SR-B1 receptors.
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102
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Westermann D, Mersmann J, Melchior A, Freudenberger T, Petrik C, Schaefer L, Lüllmann-Rauch R, Lettau O, Jacoby C, Schrader J, Brand-Herrmann SM, Young M, Schultheiss H, Levkau B, Baba H, Unger T, Zacharowski K, Tschöpe C, Fischer J. Biglycan Is Required for Adaptive Remodeling After Myocardial Infarction. Circulation 2008; 117:1269-76. [DOI: 10.1161/circulationaha.107.714147] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
After myocardial infarction (MI), extensive remodeling of extracellular matrix contributes to scar formation and preservation of hemodynamic function. On the other hand, adverse and excessive extracellular matrix remodeling leads to fibrosis and impaired function. The present study investigates the role of the small leucine-rich proteoglycan biglycan during cardiac extracellular matrix remodeling and cardiac hemodynamics after MI.
Methods and Results—
Experimental MI was induced in wild-type (WT) and
bgn
−/0
mice by permanent ligation of the left anterior descending coronary artery. Biglycan expression was strongly increased at 3, 7, and 14 days after MI in WT mice.
bgn
−/0
mice showed increased mortality rates after MI as a result of frequent left ventricular (LV) ruptures. Furthermore, tensile strength of the LV derived from
bgn
−/0
mice 21 days after MI was reduced as measured ex vivo. Collagen matrix organization was severely impaired in
bgn
−/0
mice, as shown by birefringence analysis of Sirius red staining and electron microscopy of collagen fibrils. At 21 days after MI, LV hemodynamic parameters were assessed by pressure-volume measurements in vivo to obtain LV end-diastolic pressure, end-diastolic volume, and end-systolic volume.
bgn
−/0
mice were characterized by aggravated LV dilation evidenced by increased LV end-diastolic volume (
bgn
−/0
, 111±4.2 μL versus WT, 96±4.4 μL;
P
<0.05) and LV end-diastolic pressure (
bgn
−/0
, 24±2.7 versus WT, 18±1.8 mm Hg;
P
<0.05) and severely impaired LV function (EF,
bgn
−/0
, 12±2% versus WT, 21±4%;
P
<0.05) 21 days after MI.
Conclusion—
Biglycan is required for stable collagen matrix formation of infarct scars and for preservation of cardiac hemodynamic function.
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103
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Levkau B, Schäfers M, Wohlschlaeger J, von Wnuck Lipinski K, Keul P, Hermann S, Kawaguchi N, Kirchhof P, Fabritz L, Stypmann J, Stegger L, Flögel U, Schrader J, Fischer JW, Fischer J, Hsieh P, Ou YL, Mehrhof F, Tiemann K, Ghanem A, Matus M, Neumann J, Heusch G, Schmid KW, Conway EM, Baba HA. Survivin determines cardiac function by controlling total cardiomyocyte number. Circulation 2008; 117:1583-93. [PMID: 18332262 DOI: 10.1161/circulationaha.107.734160] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Survivin inhibits apoptosis and regulates cell division in many organs, but its function in the heart is unknown. METHODS AND RESULTS We show that cardiac-specific deletion of survivin resulted in premature cardiac death. The underlying cause was a dramatic reduction in total cardiomyocyte numbers as determined by a stereological method for quantification of cells per organ. The resulting increased hemodynamic load per cell led to progressive heart failure as assessed by echocardiography, magnetic resonance imaging, positron emission tomography, and invasive catheterization. The reduction in total cardiomyocyte number in alpha-myosin heavy chain (MHC)-survivin(-/-) mice was due to an approximately 50% lower mitotic rate without increased apoptosis. This occurred at the expense of DNA accumulation because survivin-deficient cardiomyocytes displayed marked DNA polyploidy indicative of consecutive rounds of DNA replication without cell division. Survivin small interfering RNA knockdown in neonatal rat cardiomyocytes also led to polyploidization and cell cycle arrest without apoptosis. Adenoviral overexpression of survivin in cardiomyocytes inhibited doxorubicin-induced apoptosis, induced DNA synthesis, and promoted cell cycle progression. The phenotype of the alphaMHC-survivin(-/-) mice also allowed us to determine the minimum cardiomyocyte number sufficient for normal cardiac function. In human cardiomyopathy, survivin was potently induced in the failing heart and downregulated again after hemodynamic support by a left ventricular assist device. Its expression positively correlated with the mean cardiomyocyte DNA content. CONCLUSIONS We suggest that the ontogenetically determined cardiomyocyte number may be an independent factor in the susceptibility to cardiac diseases. Through its profound impact on both cardiomyocyte replication and apoptosis, survivin may emerge as a promising new target for myocardial regeneration.
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104
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Abstract
Increasing evidence suggests that High-density lipoproteins (HDL) are a direct cardioprotective agent in the setting of acute myocardial ischemia/reperfusion injury, and that this cardioprotection occurs independently of their atheroprotective effect. Studies on the involved mechanisms have revealed that the biologically active HDL-compound sphingosine-1-phosphate (S1P) is responsible for the beneficial effect of HDL on the myocardium. There appears to be an intricate interplay between known preconditioning agents and components of the S1P synthesis machinery in the heart, which makes S1P signalling an attractive downstream convergence point of preconditioning and cardioprotection at the level of its G protein-coupled receptors. While local S1P production has been known to protect the heart against ischemia/reperfusion injury and to mediate preconditioning, systemic S1P supply via HDL adds a novel aspect to the regulation of cardioprotection. Thus the S1P-content of HDL may serve both as a potential cardiovascular risk marker and a novel therapeutic target. Strategies for short-term "acute" HDL elevation as well as S1P analogues may prove beneficial not only in the high-risk patient but also in any patient at risk of myocardial ischemia.
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105
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Wagner S, Breyholz HJ, Law MP, Faust A, Höltke C, Schröer S, Haufe G, Levkau B, Schober O, Schäfers M, Kopka K. Novel fluorinated derivatives of the broad-spectrum MMP inhibitors N-hydroxy-2(R)-[[(4-methoxyphenyl)sulfonyl](benzyl)- and (3-picolyl)-amino]-3-methyl-butanamide as potential tools for the molecular imaging of activated MMPs with PET. J Med Chem 2007; 50:5752-64. [PMID: 17956082 DOI: 10.1021/jm0708533] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
An approach to the in vivo imaging of locally upregulated and activated matrix metalloproteinases (MMPs) found in many pathological processes is offered by positron emission tomography (PET). Hence, appropriate PET radioligands for MMP imaging are required. Here, we describe the syntheses of novel fluorinated MMP inhibitors (MMPIs) based on lead structures of the broad-spectrum inhibitors N-hydroxy-2(R)-[[(4-methoxyphenyl)sulfonyl](benzyl)-amino]-3-methyl-butanamide (CGS 25966) and N-hydroxy-2(R)-[[(4-methoxyphenyl)sulfonyl](3-picolyl)-amino]-3-methyl-butanamide (CGS 27023A). Additionally, tailor-made precursor compounds for radiolabeling with the positron-emitter 18F were synthesized. All prepared hydroxamate target compounds showed high in vitro MMP inhibition potencies for MMP-2, MMP-8, MMP-9, and MMP-13. As a consequence, the promising fluorinated hydroxamic acid derivative 1f was resynthesized in its 18F-labeled version via two different procedures yielding the potential PET radioligand [18F]1f. As expected, the biodistribution behavior of this novel compound and that of the more hydrophilic variant [18F]1j, also developed by our group, indicates that there was no tissue specific accumulation in wild-type (WT) mice.
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106
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Keul P, Tölle M, Lucke S, von Wnuck Lipinski K, Heusch G, Schuchardt M, van der Giet M, Levkau B. The sphingosine-1-phosphate analogue FTY720 reduces atherosclerosis in apolipoprotein e-deficient mice. J Mol Cell Cardiol 2007. [DOI: 10.1016/j.yjmcc.2007.03.676] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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107
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Hartung D, Schäfers M, Fujimoto S, Levkau B, Narula N, Kopka K, Virmani R, Reutelingsperger C, Hofstra L, Kolodgie FD, Petrov A, Narula J. Targeting of matrix metalloproteinase activation for noninvasive detection of vulnerable atherosclerotic lesions. Eur J Nucl Med Mol Imaging 2007; 34 Suppl 1:S1-8. [PMID: 17497106 DOI: 10.1007/s00259-007-0435-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
INTRODUCTION Inflammation plays an important role in vulnerability of atherosclerotic plaques to rupture and hence acute coronary events. The monocyte-macrophage infiltration in plaques leads to upregulation of cytokines and metalloproteinase enzymes. Matrix metalloproteinases result in matrix dissolution and consequently expansive remodeling of the vessel. They also contribute to attenuation of fibrous cap and hence susceptibility to rupture. Assessment of metalloproteinase expression and activity should provide information about plaque instability.
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108
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Breyholz HJ, Wagner S, Levkau B, Schober O, Schäfers M, Kopka K. A 18F-radiolabeled analogue of CGS 27023A as a potential agent for assessment of matrix-metalloproteinase activity in vivo. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF... 2007; 51:24-32. [PMID: 17372570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
AIM The non-invasive measurement of activated matrix metalloproteinases (MMPs) in vivo, which are involved in many pathophysiological and pathological processes occurring in inflammation, cancer and atherosclerosis, is a clinical challenge. A diagnostic tool for the non-invasive detection of MMP activity in vivo is based on MMP inhibitor (MMPI) radiotracers. METHODS We chose non-peptidyl broad-spectrum MMPI CGS 27023A 1 as a hydroxamic acid-based lead structure to design such a tracer. RESULTS The radioligand HO-[(123)I]I-CGS 27023A was able to specifically visualize activated MMPs in vascular lesions of apolipoprotein E-deficient mice in vivo. Based upon this work the radiosynthesis of a fluorinated analogue of the MMP inhibitor CGS 27023A was developed. Its unlabeled counterpart was found to be a potent MMP inhibitor in vitro. CONCLUSIONS Application of this class of MMP-targeting agents in combination with molecular imaging modalities, such as positron emission tomography, may emerge as a novel clinical diagnostic tool in the management of human diseases with MMP misexpression and/or dysregulation.
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109
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Faust A, Wagner S, Law MP, Hermann S, Schnöckel U, Keul P, Schober O, Schäfers M, Levkau B, Kopka K. The nonpeptidyl caspase binding radioligand (S)-1-(4-(2-[18F]Fluoroethoxy)-benzyl)-5-[1-(2-methoxymethylpyrrolidinyl)sulfonyl]isatin ([18F]CbR) as potential positron emission tomography-compatible apoptosis imaging agent. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF... 2007; 51:67-73. [PMID: 17372575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
AIM Radiolabeled Annexin V-derivatives are well characterized phosphatidylserine-targeting biomarkers and considered as state-of-the-art tracers for non-invasive molecular imaging of apoptosis. In contrast to Annexin V-derived imaging agents being surrogate markers of apoptosis, activated cysteinyl aspartate-specific proteases (caspases) represent the common final path of apoptosis being a suitable in vivo target for the exclusive imaging of apoptotic tissues in vivo. METHODS We suggest 5-pyrrolidinylsulfonyl isatins as a potential nonpeptidyl class of caspase inhibitors for the design of caspase binding radioligands (CbRs), that could be used for in vivo visualization of activated effector caspases. The caspase inhibitor (S)-(+)-5-[1-(2-Methoxy-methylpyrrolidinyl)sulfonyl]isatin 1 (K(i, caspase)-3 (1)=60 nM) was chosen as lead structure for the development of nonpeptidyl CbRs. Its structural expansion at the N-1-position the yields moderate lipophilic p-(2-fluoroethoxy)benzyl variant 2 (log D=2.2), without loss of caspase binding potency (IC(50, caspase)-3 (2)=36.4 nM). RESULTS Subsequent automated radiosynthesis of the corresponding (18)F-labeled target CbR [(18)F]2 was performed by direct (18)F-labeling of tosylate precursor 4. CONCLUSIONS As shown by biodistribution studies and small animal positron emission tomography a nonpeptidyl 5-pyrrolidinylsulfonyl isatin-type caspase inhibitor (S)-1-(4-(2-[(18)F]Fluoroetho-xy)benzyl)-5-[1-(2-methoxymethylpyrrolidinyl)sulfonyl]isatin [(18)F]2 with rapid blood clearance characteristics could potentially detect apoptosis in vivo.
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110
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Tölle M, Levkau B, Kleuser B, van der Giet M. Sphingosine-1-phosphate and FTY720 as anti-atherosclerotic lipid compounds. Eur J Clin Invest 2007; 37:171-9. [PMID: 17359484 DOI: 10.1111/j.1365-2362.2007.01776.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
All stages of atherosclerosis have been identified as a chronic vascular inflammatory disease. In the last few years there is increasing evidence that endogenous lysophospholipids such as sphingosine-1-phosphate (S1P) have potent anti-inflammatory properties. The S1P analogue FTY720 that has been developed as a potent, orally active, immunosuppressant in the field of transplantation and autoimmune disease has interesting effects on inflammatory processes in the arterial vessel wall. S1P targets five specific S1P receptors (S1P(1-5)), which are ubiquitously expressed. S1P(1-3) receptor expression is identified in arterial vessels. S1P and FTY720 show potent silencing effects on some vascular proinflammatory mechanisms in endothelial and vascular smooth muscle cells. In addition, the interaction of monocytes with the vessel wall is inhibited. As shown recently, FTY720 can effectively reduce the progression of atherosclerosis in apolipoprotein E-deficient mice having a high-cholesterol diet. It is not entirely clear which S1P receptor subtype is mainly involved in this process. However, it is currently speculated that the S1P(3) and probably the S1P(1) is involved in the anti-atherosclerotic effects of FTY720. This review summarizes the current knowledge about S1P- and FTY720-effects on mechanisms of vascular inflammatory disease. In addition S1P receptor subtypes are identified which might be interesting for molecular drug targeting.
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111
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Ferri N, Colombo G, Ferrandi C, Raines EW, Levkau B, Corsini A. Simvastatin reduces MMP1 expression in human smooth muscle cells cultured on polymerized collagen by inhibiting Rac1 activation. Arterioscler Thromb Vasc Biol 2007; 27:1043-9. [PMID: 17303772 DOI: 10.1161/atvbaha.107.139881] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Activation of collagen receptors expressed by smooth muscle cells induces matrix metalloproteinase (MMP) expression. The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) have been shown to interfere with integrin signaling, but their effects on collagen receptor-mediated MMP expression have not been investigated. METHODS AND RESULTS In the present study, we show that simvastatin (3 micromol/L) reduces MMP1 expression and secretion in human smooth muscle cells cultured on polymerized type I collagen by 39.9+/-11.2% and 36.0+/-2.3%, respectively. Reduced MMP1 protein levels correlate with a similar decrease in MMP1 promoter activity (-33.0+/-8.9%), MMP1 mRNA levels (-37.8+/-10.5%), and attenuation of smooth muscle cell collagen degradation (-34.2+/-6.1%). Mevalonate, and the isoprenoid derivative geranylgeraniol, precursors of geranylgeranylated proteins, completely prevent the inhibitory effect of simvastatin on MMP1. Moreover, the protein geranylgeranyltransferase inhibitor GGTI-286 significantly decreases MMP1 expression. Retroviral overexpression of dominant-negative mutants of geranylgeranylated Rac1 lead to a reduction of MMP1 protein (-50.4+/-5.4%) and mRNA levels (-97.9+/-1.0%), and knockdown of Rac1 by small interfering RNA downregulates MMP1 expression. Finally, simvastatin reduces GTP-bound Rac1 expression levels in smooth muscle cells cultured on polymerized collagen. CONCLUSIONS These results demonstrate that simvastatin, by inhibiting Rac1 activity, reduces MMP1 expression and collagen degradation in human smooth muscle cells.
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MESH Headings
- Cells, Cultured
- Collagen/pharmacology
- Gene Expression/drug effects
- Humans
- Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology
- Infant, Newborn
- Leucine/analogs & derivatives
- Leucine/pharmacology
- Matrix Metalloproteinase 1/biosynthesis
- Matrix Metalloproteinase 1/genetics
- Matrix Metalloproteinase Inhibitors
- Mevalonic Acid/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Polymerase Chain Reaction
- RNA, Messenger/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Signal Transduction/drug effects
- Simvastatin/pharmacology
- rac1 GTP-Binding Protein/antagonists & inhibitors
- rac1 GTP-Binding Protein/metabolism
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112
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Walter DH, Rochwalsky U, Reinhold J, Seeger F, Aicher A, Urbich C, Spyridopoulos I, Chun J, Brinkmann V, Keul P, Levkau B, Zeiher AM, Dimmeler S, Haendeler J. Sphingosine-1-Phosphate Stimulates the Functional Capacity of Progenitor Cells by Activation of the CXCR
4
-Dependent Signaling Pathway via the S1P
3
Receptor. Arterioscler Thromb Vasc Biol 2007; 27:275-82. [PMID: 17158356 DOI: 10.1161/01.atv.0000254669.12675.70] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Objective—
Sphingosine-1-phosphate (S1P) is a bioactive lipid, which influences migration and proliferation of endothelial cells through activation of S1P receptors and has been shown to support SDF-1 induced migration and bone marrow homing of CD34
+
progenitors.
Methods and Results—
Here, we show that incubation of patient-derived endothelial progenitor cells (EPCs) with S1P or its synthetic analog FTY720 improved blood flow recovery in ischemic hind limbs. Likewise, recovery of blood flow was dramatically reduced after induction of hindlimb ischemia in mice deficient for the S1P receptor 3 (S1P
3
). S1P
3
−/−
bone marrow–derived mononuclear cells (BMCs) failed to augment neovascularization after hind limb ischemia. Of note, treatment of BMCs derived from S1P
3
−/−
mice with S1P did not rescue blood flow recovery. Mechanistically, S1P and FTY720 induced phosphorylation of CXCR
4
, activated the Src kinase, and stimulated phosphorylation of JAK2. The contribution of CXCR
4
for S1P-mediated effects was further supported by the findings that S1P preincubation failed to stimulate invasion capacity and in vivo blood flow recovery of BMCs from CXCR
4
+/−
mice. The activation of CXCR
4
was dependent on the Src kinase family as demonstrated by preincubation with the Src inhibitor PP2. The activation of the CXCR
4
signaling by S1P is mediated via the S1P
3
receptor, since S1P-induced Src phosphorylation was abrogated in EPC from S1P
3
−/−
mice.
Conclusions—
S1P agonists might serve as sensitizers of CXCR
4
-mediated signaling and may be applied in clinical progenitor cell therapy to improve EPC or BMC function in patients with coronary artery disease.
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113
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August C, Brockmann J, Vowinkel T, Wolters H, Dietl KH, Levkau B, Heidenreich S, Lang D, Baba HA. Stress associated proteins metallothionein, HO-1 and HSP 70 in human zero-hour biopsies of transplanted kidneys. Virchows Arch 2007; 449:192-9. [PMID: 16738898 DOI: 10.1007/s00428-006-0216-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2006] [Accepted: 04/04/2006] [Indexed: 01/16/2023]
Abstract
Light microscopic alterations reflecting both previous and preservation-induced changes in the donor organ are usually not very distinctive. The ischemia/reperfusion-associated injury depends primarily on the conditions of donor organ preservation. The present study examined human kidney biopsies with special attention paid to the molecular mechanisms of preservation-induced injury preceding reperfusion. Stress-associated proteins hemeoxygenase-1 (HO-1), heat shock protein 70 (HSP 70), and metallothionein (MT) were studied in human zero-hour biopsies of transplanted kidneys prior to reperfusion in 29 patients. Protein expression was evaluated by semiquantitative immunohistochemistry and Western blotting for HO-1 and HSP 70. These findings were correlated with terminal deoxynucleotidyltransferase-mediated 2'-deoxyuridine 5'-triphosphate-digoxigenin nick end labeling (TUNEL) staining and follow up. Compared to controls, MT and HSP 70 expression was significantly higher at zero hour. In contrast, HO-1 and the number of TUNEL-positive cells were not elevated. MT and HO-1 immunoexpression were inversely associated with graft function, and hence, were of prognostic relevance. MT and HSP 70 were sensitive to the duration of cold ischemia. MT and HO-1 are suitable indicators for tissue injury during ischemia and may serve as new predictive markers that need to be validated in further independent studies.
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114
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Wohlschlaeger J, Schmitz KJ, Palatty J, Takeda A, Takeda N, Vahlhaus C, Levkau B, Stypmann J, Schmid C, Schmid KW, Baba HA. Roles of cyclooxygenase-2 and phosphorylated Akt (Thr308) in cardiac hypertrophy regression mediated by left-ventricular unloading. J Thorac Cardiovasc Surg 2007; 133:37-43. [PMID: 17198778 DOI: 10.1016/j.jtcvs.2006.07.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Revised: 06/29/2006] [Accepted: 07/31/2006] [Indexed: 11/21/2022]
Abstract
OBJECTIVES Cyclooxygenase-2 is associated with cardiac hypertrophy during chronic heart failure and is regulated through the PI3K/Akt pathway. Cyclooxygenase-2-induced cell growth through Akt phosphorylation was demonstrated in vitro. In chronic heart failure, left ventricular assist devices lead to hypertrophy regression and molecular changes. Therefore, the expression of cyclooxygenase-2, phosphorylated Akt (p-Akt), and p-Erk 1/2, as well as cardiac hypertrophy before and after left ventricular assist device insertion, was investigated. METHODS In myocardial tissue before and after left ventricular assist device insertion, the expression of cyclooxygenase-2, p-Akt (Thr308), p-Akt (Ser473), and p-Erk 1/2 was demonstrated by immunohistochemistry and quantified by morphometry. Colocalization of cyclooxygenase-2 and p-Akt (Thr308) was investigated by immuno-doublestaining. RESULTS A significant decrease of cyclooxygenase-2, p-Akt (Thr308), p-Akt (Ser473), and p-Erk 1/2 protein expression and hypertrophy regression was observed after left ventricular assist device insertion. A significant correlation between cyclooxygenase-2 and p-Akt (Thr308) expression, as well as between cyclooxygenase-2 expression and cardiomyocyte diameter, was observed before, but not after, left ventricular assist device insertion. Only cyclooxygenase-2-positive cardiomyocytes showed significant hypertrophy regression on unloading. Sarcoplasmic colocalization of cyclooxygenase-2 and p-Akt (Thr308) is present before left ventricular assist device insertion and is decreased after unloading, whereas the normal myocardium is completely devoid of it. CONCLUSIONS Left ventricular assist device treatment is associated with a significant decrease of cyclooxygenase-2, p-Akt (Thr308), p-Akt (Ser473), and p-Erk 1/2, and cardiac hypertrophy regression of cyclooxygenase-2-positive cardiomyocytes. The significant correlation and colocalization in cardiomyocytes of cyclooxygenase-2 and p-Akt (Thr308) before left ventricular assist device insertion suggests a cross-talk between the 2 molecules in the progression of cardiac hypertrophy, which is reversibly regulated by the left ventricular assist device.
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115
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Levkau B. Pathogenese und molekulare Targets kardiovaskulärer Erkrankungen. ROFO-FORTSCHR RONTG 2007. [DOI: 10.1055/s-2007-976747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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116
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Keul P, Tölle M, Lucke S, von Wnuck Lipinski K, Heusch G, Schuchardt M, van der Giet M, Levkau B. The sphingosine-1-phosphate analogue FTY720 reduces atherosclerosis in apolipoprotein E-deficient mice. Arterioscler Thromb Vasc Biol 2006; 27:607-13. [PMID: 17158351 DOI: 10.1161/01.atv.0000254679.42583.88] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The sphingosine-1-phosphate (S1P) analogue FTY720 is a potent immunosuppressive agent currently in Phase III clinical trials for kidney transplantation. FTY720 traps lymphocytes in secondary lymphoid organs thereby preventing their migration to inflammatory sites. Previously, we have identified FTY720 as a potent activator of eNOS. As both inhibition of immune responses and stimulation of eNOS may attenuate atherosclerosis, we administered FTY720 to apolipoprotein E-/- mice fed a high-cholesterol diet. METHODS AND RESULTS FTY720 dramatically reduced atherosclerotic lesion volume (62.5%), macrophage (41.8%), and collagen content (63.5%) after 20 weeks of high-cholesterol diet. In isolated aortic segments and cultured vascular smooth muscle cell, FTY720 potently inhibited thrombin-induced release of monocyte chemoattractant protein-1. This effect was mediated by the S1P3 sphingolipid receptor as FTY720 had no effect on thrombin-induced monocyte chemoattractant protein-1 release in S1P3-/- mice. In contrast to S1P receptors on lymphocytes, FTY720 did not desensitize vascular S1P receptors as arteries from FTY720-treated mice retained their vasodilator response to FTY720-phosphate. CONCLUSIONS We suggest that FTY720 inhibits atherosclerosis by suppressing the machinery involved in monocyte/macrophage emigration to atherosclerotic lesions. As vascular S1P receptors remained functional under FTY720 treatment, S1P agonists that selectively target the vasculature and not the immune system may be promising new drugs against atherosclerosis.
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MESH Headings
- Animals
- Apolipoproteins E/deficiency
- Atherosclerosis/physiopathology
- Atherosclerosis/prevention & control
- Cell Movement/drug effects
- Cells, Cultured
- Cholesterol, Dietary/administration & dosage
- Cytokines/genetics
- Cytokines/metabolism
- Disease Models, Animal
- Fingolimod Hydrochloride
- Gene Expression Regulation
- Immunohistochemistry
- Lysophospholipids
- Mice
- Mice, Inbred C57BL
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Probability
- Propylene Glycols/pharmacology
- RNA, Messenger/analysis
- Reverse Transcriptase Polymerase Chain Reaction
- Sphingosine/analogs & derivatives
- Sphingosine/pharmacology
- Statistics, Nonparametric
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117
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Kirchhof P, Fabritz L, Zwiener M, Witt H, Schäfers M, Zellerhoff S, Paul M, Athai T, Hiller KH, Baba HA, Breithardt G, Ruiz P, Wichter T, Levkau B. Age- and Training-Dependent Development of Arrhythmogenic Right Ventricular Cardiomyopathy in Heterozygous Plakoglobin-Deficient Mice. Circulation 2006; 114:1799-806. [PMID: 17030684 DOI: 10.1161/circulationaha.106.624502] [Citation(s) in RCA: 289] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited disorder that causes sudden death and right ventricular heart failure in the young. Clinical data suggest that competitive sports may provoke ARVC in susceptible persons. Genetically, loss-of-function mutations in desmosomal proteins (plakophilin, desmoplakin, or plakoglobin) have been associated with ARVC. To test the hypothesis that reduced desmosomal protein expression causes ARVC, we studied the cardiac effects of heterozygous plakoglobin deficiency in mice.
Methods and Results—
Ten-month-old heterozygous plakoglobin-deficient mice (plakoglobin
+/−
) had increased right ventricular volume, reduced right ventricular function, and spontaneous ventricular ectopy (all
P
<0.05). Left ventricular size and function were not altered. Isolated, perfused plakoglobin
+/−
hearts had spontaneous ventricular tachycardia of right ventricular origin and prolonged right ventricular conduction times compared with wild-type hearts. Endurance training accelerated the development of right ventricular dysfunction and arrhythmias in plakoglobin
+/−
mice. Histology and electron microscopy did not identify right ventricular abnormalities in affected animals.
Conclusions—
Heterozygous plakoglobin deficiency provokes ARVC. Manifestation of the phenotype is accelerated by endurance training. This suggests a functional role for plakoglobin and training in the development of ARVC.
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MESH Headings
- Aging/physiology
- Animals
- Arrhythmogenic Right Ventricular Dysplasia/epidemiology
- Arrhythmogenic Right Ventricular Dysplasia/etiology
- Arrhythmogenic Right Ventricular Dysplasia/genetics
- Arrhythmogenic Right Ventricular Dysplasia/pathology
- Arrhythmogenic Right Ventricular Dysplasia/physiopathology
- Desmosomes/pathology
- Disease Models, Animal
- Electrocardiography
- Gene Expression Regulation
- Genetic Predisposition to Disease
- Glucose/metabolism
- Heterozygote
- Hypertrophy, Right Ventricular/etiology
- Hypertrophy, Right Ventricular/genetics
- Hypertrophy, Right Ventricular/pathology
- Mice
- Mice, Knockout
- Models, Cardiovascular
- Myocardial Contraction
- Myocardium/metabolism
- Myocardium/ultrastructure
- Phenotype
- Physical Conditioning, Animal/adverse effects
- Stress, Physiological/physiopathology
- Swimming
- Tachycardia, Ventricular/etiology
- Tachycardia, Ventricular/genetics
- Ventricular Dysfunction, Right/etiology
- Ventricular Dysfunction, Right/genetics
- Ventricular Premature Complexes/etiology
- Ventricular Premature Complexes/genetics
- gamma Catenin/deficiency
- gamma Catenin/genetics
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118
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Kopka K, Faust A, Keul P, Wagner S, Breyholz HJ, Höltke C, Schober O, Schäfers M, Levkau B. 5-Pyrrolidinylsulfonyl Isatins as a Potential Tool for the Molecular Imaging of Caspases in Apoptosis. J Med Chem 2006; 49:6704-15. [PMID: 17154501 DOI: 10.1021/jm051217c] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Caspases are the unique enzymes responsible for the execution of the cell death program and may represent an exclusive target for the specific molecular imaging of apoptosis in vivo. 5-Pyrrolidinylsulfonyl isatins represent potent nonpeptidyl caspase inhibitors that may be suitable for the development of caspase binding radioligands (CBRs). (S)-5-[1-(2-Methoxymethylpyrrolidinyl)sulfonyl]isatin (7) served as a lead compound for modification of its N-1-position. Corresponding pairs of N-1-substituted 2-methoxymethyl- and 2-phenoxymethylpyrrolidinyl derivatives were examined in vitro by biochemical caspase inhibition assays. All target compounds possess high in vitro caspase inhibition potencies in the nanomolar to subnanomolar range for caspase-3 (Ki=0.2-56.1 nM). As shown for compound (S)-1-(4-(2-fluoroethoxy)benzyl)-5-[1-(2-methoxymethylpyrrolidinyl)sulfonyl]isatin (35), the class of N-1-substituted 5-pyrrolidinylsulfonyl isatins competitively inhibits caspase-3. All caspase inhibitors show selectivity for the effector caspases-3 and -7 in vitro. The 2-methoxymethylpyrrolidinyl versions of the isatins appear to possess superior caspase inhibition potencies in cellular apoptosis inhibition assays compared with the 2-phenoxymethylpyrrolidinyl inhibitors.
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119
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Wagner S, Breyholz HJ, Faust A, Höltke C, Levkau B, Schober O, Schäfers M, Kopka K. Molecular Imaging of Matrix Metalloproteinases In Vivo Using Small Molecule Inhibitors for SPECT and PET. Curr Med Chem 2006; 13:2819-38. [PMID: 17073631 DOI: 10.2174/092986706778522002] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Matrix metalloproteinases (MMPs) are a family of zinc- and calcium-dependent secreted or membrane anchored endopeptidases. MMPs are involved in many physiological processes but also take part in the pathophysiological mechanisms responsible for a wide range of diseases. Pathological expression and activation of MMPs are associated with cancer, atherosclerosis, stroke, arthritis, periodontal disease, multiple sclerosis and liver fibrosis. Thus, noninvasive visualisation and quantification of MMP activity in vivo are of great interest in basic research and clinical application. This can be achieved by scintigraphic molecular imaging techniques such as single photon emission computed tomography (SPECT) and positron emission tomography (PET) provided suitable radiolabelled tracers exist, e.g. radioactive inhibitors of matrix metalloproteinases (MMPIs). The approach to monitor MMP activity in vivo using radiolabelled small molecule inhibitors suitable for SPECT and PET is summarised in this review. Briefly, latest advances in scintigraphic imaging are introduced and followed by a report about the enzyme class of MMPs. The involvement of MMPs in cancer and atherosclerosis is exemplified and small molecule MMPIs are classified. Subsequently, the development of radiolabelled small molecule MMPIs, their synthesis and in vitro and in vivo evaluation is reviewed. Finally, an outlook on the clinical potential of labelled MMPIs in diagnostic algorithms is given.
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120
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Theilmeier G, Schmidt C, Herrmann J, Keul P, Schäfers M, Herrgott I, Mersmann J, Larmann J, Hermann S, Stypmann J, Schober O, Hildebrand R, Schulz R, Heusch G, Haude M, von Wnuck Lipinski K, Herzog C, Schmitz M, Erbel R, Chun J, Levkau B. High-density lipoproteins and their constituent, sphingosine-1-phosphate, directly protect the heart against ischemia/reperfusion injury in vivo via the S1P3 lysophospholipid receptor. Circulation 2006; 114:1403-9. [PMID: 16982942 DOI: 10.1161/circulationaha.105.607135] [Citation(s) in RCA: 319] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND All treatments of acute myocardial infarction are aimed at rapid revascularization of the occluded vessel; however, no clinical strategies are currently available to protect the heart from ischemia/reperfusion injury after restitution of blood flow. We hypothesized that some of the cholesterol transport-independent biological properties of high-density lipoprotein (HDL) implied in atheroprotection may also be beneficial in settings of acute myocardial reperfusion injury. METHODS AND RESULTS In an in vivo mouse model of myocardial ischemia/reperfusion, we observed that HDL and its sphingolipid component, sphingosine-1-phosphate (S1P), dramatically attenuated infarction size by approximately 20% and 40%, respectively. The underlying mechanism was an inhibition of inflammatory neutrophil recruitment and cardiomyocyte apoptosis in the infarcted area. In vitro, HDL and S1P potently suppressed leukocyte adhesion to activated endothelium under flow and protected rat neonatal cardiomyocytes against apoptosis. In vivo, HDL- and S1P-mediated cardioprotection was dependent on nitric oxide (NO) and the S1P3 lysophospholipid receptor, because it was abolished by pharmacological NO synthase inhibition and was completely absent in S1P3-deficient mice. CONCLUSIONS Our data demonstrate that HDL and its constituent, S1P, acutely protect the heart against ischemia/reperfusion injury in vivo via an S1P3-mediated and NO-dependent pathway. A rapid therapeutic elevation of S1P-containing HDL plasma levels may be beneficial in patients at high risk of acute myocardial ischemia.
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MESH Headings
- Animals
- Apoptosis/drug effects
- Cardiotonic Agents/pharmacology
- Cardiotonic Agents/therapeutic use
- Cell Adhesion/drug effects
- Cells, Cultured/drug effects
- Chemotaxis, Leukocyte/drug effects
- Endothelial Cells/drug effects
- Endothelial Cells/physiology
- Female
- Humans
- Lipoproteins, HDL/pharmacology
- Lipoproteins, HDL/physiology
- Lipoproteins, HDL/therapeutic use
- Lipoproteins, LDL/pharmacology
- Lysophospholipids/pharmacology
- Lysophospholipids/physiology
- Lysophospholipids/therapeutic use
- Macrophages/physiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Myocardial Ischemia/drug therapy
- Myocardial Reperfusion Injury/prevention & control
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/pathology
- NG-Nitroarginine Methyl Ester/pharmacology
- Nitric Oxide/physiology
- Nitric Oxide Synthase/antagonists & inhibitors
- Receptors, Lysosphingolipid/deficiency
- Receptors, Lysosphingolipid/drug effects
- Receptors, Lysosphingolipid/genetics
- Receptors, Lysosphingolipid/physiology
- Sphingosine/analogs & derivatives
- Sphingosine/pharmacology
- Sphingosine/physiology
- Sphingosine/therapeutic use
- Sphingosine-1-Phosphate Receptors
- Tumor Necrosis Factor-alpha/pharmacology
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121
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Lucke S, Levkau B. Cleavage of eNOS by caspases inhibits nitric oxide (NO) generation during endothelial cell apoptosis. Vascul Pharmacol 2006. [DOI: 10.1016/j.vph.2006.08.369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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122
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von Wnuck Lipinski K, Levkau B. Rigidity of collagen governs apoptosis and expression of inhibitor of apoptosis proteins (IAPS) in vascular smooth muscle cells. Vascul Pharmacol 2006. [DOI: 10.1016/j.vph.2006.08.153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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123
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Keul P, Faust A, Wagner S, Schober O, Kopka K, Schaefers M, Levkau B. Isatin-based caspase inhibitors as novel pet-compatible radioligands for molecular imaging of apoptosis in vivo. Vascul Pharmacol 2006. [DOI: 10.1016/j.vph.2006.08.298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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124
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von Wnuck Lipinski K, Keul P, Ferri N, Lucke S, Heusch G, Fischer JW, Levkau B. Integrin-Mediated Transcriptional Activation of Inhibitor of Apoptosis Proteins Protects Smooth Muscle Cells Against Apoptosis Induced by Degraded Collagen. Circ Res 2006; 98:1490-7. [PMID: 16728660 DOI: 10.1161/01.res.0000229267.77982.0d] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Apoptosis of smooth muscle cells (SMC) and degradation of the extracellular matrix (ECM) have both been implicated in atherosclerotic plaque rupture. We have previously reported that degraded type I collagen fragments induce a rapid but transient apoptotic burst initiated by calpains in SMC. The aim of the current study was to identify the pathway responsible for consecutive SMC survival. We show that exposure of SMC to collagen fragments resulted in a sustained activation of nuclear factor (NF)-κB via phosphorylation and degradation of IκBα. Its prevention through retroviral expression of superrepressor IκBα or proteasome inhibition potently induced apoptosis. In the presence of blocking antibodies to α
v
β
3
integrin and RGD peptides, collagen fragments no longer activated NF-κB and apoptosis was enhanced. The mechanism by which NF-κB was protecting SMC against collagen fragment-induced apoptosis was a transcriptional activation of several endogenous caspase inhibitors of the inhibitor of apoptosis protein (IAP) family as: (1) the expression of xIAP, c-IAP2, and survivin was potently induced by collagen fragments; (2) IAP expression was abrogated by superrepressor IκBα; and (3) knockdown of each of the 3 IAPs by small interfering RNA (siRNA) resulted in enhanced apoptosis after collagen fragment treatment. Our data suggest that SMC exposed to degraded collagen are protected against apoptosis by a mechanism involving α
v
β
3
-dependent NF-κB activation with consequent activation of IAPs. This may constitute a novel antiapoptotic pathway ensuring SMC survival in settings of enhanced ECM degradation such as cell migration, vascular remodeling, and atherosclerotic plaque rupture.
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125
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Sohn D, Totzke G, Essmann F, Schulze-Osthoff K, Levkau B, Jänicke RU. The proteasome is required for rapid initiation of death receptor-induced apoptosis. Mol Cell Biol 2006; 26:1967-78. [PMID: 16479014 PMCID: PMC1430261 DOI: 10.1128/mcb.26.5.1967-1978.2006] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Due to their tremendous apoptosis-inducing potential, proteasomal inhibitors (PIs) have recently entered clinical trials. Here we show, however, that various PIs rescued proliferating tumor cells from death receptor-induced apoptosis. This protection correlated with the stabilization of X-linked IAP (XIAP) and c-FLIP and the inhibition of caspase activation. Together with the observation that PIs could not protect cells expressing XIAP or c-FLIP short interfering RNAs (siRNAs) from death receptor-induced apoptosis, our results demonstrate that PIs mediate their protective effect via the stabilization of these antiapoptotic proteins. Furthermore, we show that once these proteins were eliminated, either by long-term treatment with death receptor ligands or by siRNA-mediated suppression, active caspases accumulated to an even larger extent in the presence of PIs. Together, our data support a biphasic role for the proteasome in apoptosis, as they show that its constitutive activity is crucial for the rapid initiation of the death program by eliminating antiapoptotic proteins, whereas at later stages, the proteasome acts in an antiapoptotic manner due to the proteolysis of caspases. Thus, for a successful PI-based tumor therapy, it is crucial to carefully evaluate basal proteasomal activity and the status of antiapoptotic proteins, as their PI-mediated prolonged stability might even cause adverse effects, leading to the survival of a tumor.
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