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Prim DA, Potts JD, Eberth JF. Pulsatile Perfusion Bioreactor for Biomimetic Vascular Impedances. J Med Device 2018. [DOI: 10.1115/1.4040648] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Pulsatile waves of blood pressure and flow are continuously augmented by the resistance, compliance, and inertance properties of the vasculature, resulting in unique wave characteristics at distinct anatomical locations. Hemodynamically generated loads, transduced as physical signals into resident vascular cells, are crucial to the maintenance and preservation of a healthy vascular physiology; thus, failure to recreate biomimetic loading in vitro can lead to pathological gene expression and aberrant remodeling. As a generalized approach to improve native and engineered blood vessels, we have designed, built, and tested a pulsatile perfusion bioreactor based on biomimetic impedances and a novel five-element electrohydraulic analog. Here, the elements of an incubator-based culture system were formulaically designed to match the vascular impedance of a brachial artery by incorporating both the inherent (systemic) and added elements of the physical system into the theoretical approach. Freshly harvested porcine saphenous veins were perfused within a physiological culture chamber for 6 h and the relative expression of seven known mechanically sensitive remodeling genes analyzed using the quantitative polymerase chain reaction (qPCR) method. Of these, we found plasminogen activator inhibitor-1 (SERPINE1) and fibronectin-1 (FN1) to be highly sensitive to differences between arterial- and venous-like culture conditions. The analytical approach and biological confirmation provide a framework toward the general design of long-term hemodynamic-mimetic vascular culture systems.
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Affiliation(s)
- David A. Prim
- College of Engineering and Computing, Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208
| | - Jay D. Potts
- School of Medicine, Department of Cell Biology and Anatomy, College of Engineering and Computing, Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208
| | - John F. Eberth
- School of Medicine, Department of Cell Biology and Anatomy, College of Engineering and Computing, Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208 e-mail:
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Prim DA, Menon V, Hasanian S, Carter L, Shazly T, Potts JD, Eberth JF. Perfusion Tissue Culture Initiates Differential Remodeling of Internal Thoracic Arteries, Radial Arteries, and Saphenous Veins. J Vasc Res 2018; 55:255-267. [PMID: 30179877 DOI: 10.1159/000492484] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 07/23/2018] [Indexed: 01/26/2023] Open
Abstract
Adaptive remodeling processes are essential to the maintenance and viability of coronary artery bypass grafts where clinical outcomes depend strongly on the tissue source. In this investigation, we utilized an ex vivo perfusion bioreactor to culture porcine analogs of common human bypass grafts: the internal thoracic artery (ITA), the radial artery (RA), and the great saphenous vein (GSV), and then evaluated samples acutely (6 h) and chronically (7 days) under in situ or coronary-like perfusion conditions. Although morphologically similar, primary cells harvested from the ITA illustrated lower intimal and medial, but not adventitial, cell proliferation rates than those from the RA or GSV. Basal gene expression levels were similar in all vessels, with only COL3A1, SERPINE1, FN1, and TGFB1 being differentially expressed prior to culture; however, over half of all genes were affected nominally by the culturing process. When exposed to coronary-like conditions, RAs and GSVs experienced pathological remodeling not present in ITAs or when vessels were studied in situ. Many of the remodeling genes perturbed at 6 h were restored after 7 days (COL3A1, FN1, MMP2, and TIMP1) while others (SERPINE1, TGFB1, and VCAM1) were not. The findings elucidate the potential mechanisms of graft failure and highlight strategies to encourage healthy ex vivo pregraft conditioning.
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Affiliation(s)
- David A Prim
- Biomedical Engineering Program, College of Engineering and Computing, University of South Carolina, Columbia, South Carolina, USA
| | - Vinal Menon
- Department of Cell Biology and Anatomy, School of Medicine, University of South Carolina, Columbia, South Carolina, USA
| | - Shahd Hasanian
- Biomedical Engineering Program, College of Engineering and Computing, University of South Carolina, Columbia, South Carolina, USA
| | - Laurel Carter
- Department of Cell Biology and Anatomy, School of Medicine, University of South Carolina, Columbia, South Carolina, USA
| | - Tarek Shazly
- Biomedical Engineering Program, College of Engineering and Computing, University of South Carolina, Columbia, South Carolina, USA.,Mechanical Engineering, College of Engineering and Computing, University of South Carolina, Columbia, South Carolina, USA
| | - Jay D Potts
- Biomedical Engineering Program, College of Engineering and Computing, University of South Carolina, Columbia, South Carolina, USA.,Department of Cell Biology and Anatomy, School of Medicine, University of South Carolina, Columbia, South Carolina, USA
| | - John F Eberth
- Biomedical Engineering Program, College of Engineering and Computing, University of South Carolina, Columbia, South Carolina, .,Department of Cell Biology and Anatomy, School of Medicine, University of South Carolina, Columbia, South Carolina,
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Ruiter MS, Pesce M. Mechanotransduction in Coronary Vein Graft Disease. Front Cardiovasc Med 2018; 5:20. [PMID: 29594150 PMCID: PMC5861212 DOI: 10.3389/fcvm.2018.00020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/22/2018] [Indexed: 12/19/2022] Open
Abstract
Autologous saphenous veins are the most commonly used conduits in revascularization of the ischemic heart by coronary artery bypass graft surgery, but are subject to vein graft failure. The current mini review aims to provide an overview of the role of mechanotransduction signalling underlying vein graft failure to further our understanding of the disease progression and to improve future clinical treatment. Firstly, limitation of damage during vein harvest and engraftment can improve outcome. In addition, cell cycle inhibition, stimulation of Nur77 and external grafting could form interesting therapeutic options. Moreover, the Hippo pathway, with the YAP/TAZ complex as the main effector, is emerging as an important node controlling conversion of mechanical signals into cellular responses. This includes endothelial cell inflammation, smooth muscle cell proliferation/migration, and monocyte attachment/infiltration. The combined effects of expression levels and nuclear/cytoplasmic translocation make YAP/TAZ interesting novel targets in the prevention and treatment of vein graft disease. Pharmacological, molecular and/or mechanical conditioning of saphenous vein segments between harvest and grafting may potentiate targeted and specific treatment to improve long-term outcome.
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Affiliation(s)
- Matthijs Steven Ruiter
- Cardiovascular Tissue Engineering Unit, Centro Cardiologico Monzino (IRCCS), Milan, Italy
| | - Maurizio Pesce
- Cardiovascular Tissue Engineering Unit, Centro Cardiologico Monzino (IRCCS), Milan, Italy
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Piola M, Prandi F, Fiore GB, Agrifoglio M, Polvani G, Pesce M, Soncini M. Human Saphenous Vein Response to Trans-wall Oxygen Gradients in a Novel Ex Vivo Conditioning Platform. Ann Biomed Eng 2015; 44:1449-61. [PMID: 26319011 DOI: 10.1007/s10439-015-1434-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 08/18/2015] [Indexed: 11/30/2022]
Abstract
Autologous saphenous veins are commonly used for the coronary artery bypass grafting even if they are liable to progressive patency reduction, known as 'vein graft disease'. Although several cellular and molecular causes for vein graft disease have been identified using in vivo models, the metabolic cues induced by sudden interruption of vasa vasorum blood supply have remained unexplored. In the present manuscript, we describe the design of an ex vivo culture system allowing the generation of an oxygen gradient between the luminal and the adventitial sides of the vein. This system featured a separation between the inner and the outer vessel culture circuits, and integrated a purpose-developed de-oxygenator module enabling the trans-wall oxygen distribution (high oxygen level at luminal side and low oxygen level at the adventitial side) existing in arterialized veins. Compared with standard cultures the bypass-specific conditions determined a significant increase in the proliferation of cells around adventitial vasa vasorum and an elevation in the length density of small and large caliber vasa vasorum. These results suggest, for the first time, a cause-effect relationship between the vein adventitial hypoxia and a neo-vascularization process, a factor known to predispose the arterialized vein conduits to restenosis.
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Affiliation(s)
- Marco Piola
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133, Milan, Italy.
| | - Francesca Prandi
- Unità di Ingegneria Tissutale, Centro Cardiologico Monzino-IRCCS, Via Parea 4, 20138, Milan, Italy
| | - Gianfranco Beniamino Fiore
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133, Milan, Italy
| | - Marco Agrifoglio
- Dipartimento di Scienze Cliniche e di Comunità, Università di Milano, Via Parea 4, 20138, Milan, Italy
| | - Gianluca Polvani
- Dipartimento di Scienze Cliniche e di Comunità, Università di Milano, Via Parea 4, 20138, Milan, Italy
| | - Maurizio Pesce
- Unità di Ingegneria Tissutale, Centro Cardiologico Monzino-IRCCS, Via Parea 4, 20138, Milan, Italy
| | - Monica Soncini
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133, Milan, Italy
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Longchamp A, Allagnat F, Berard X, Alonso F, Haefliger JA, Deglise S, Corpataux JM. Procedure for human saphenous veins ex vivo perfusion and external reinforcement. J Vis Exp 2014:e52079. [PMID: 25350681 DOI: 10.3791/52079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The mainstay of contemporary therapies for extensive occlusive arterial disease is venous bypass graft. However, its durability is threatened by intimal hyperplasia (IH) that eventually leads to vessel occlusion and graft failure. Mechanical forces, particularly low shear stress and high wall tension, are thought to initiate and to sustain these cellular and molecular changes, but their exact contribution remains to be unraveled. To selectively evaluate the role of pressure and shear stress on the biology of IH, an ex vivo perfusion system (EVPS) was created to perfuse segments of human saphenous veins under arterial regimen (high shear stress and high pressure). Further technical innovations allowed the simultaneous perfusion of two segments from the same vein, one reinforced with an external mesh. Veins were harvested using a no-touch technique and immediately transferred to the laboratory for assembly in the EVPS. One segment of the freshly isolated vein was not perfused (control, day 0). The two others segments were perfused for up to 7 days, one being completely sheltered with a 4 mm (diameter) external mesh. The pressure, flow velocity, and pulse rate were continuously monitored and adjusted to mimic the hemodynamic conditions prevailing in the femoral artery. Upon completion of the perfusion, veins were dismounted and used for histological and molecular analysis. Under ex vivo conditions, high pressure perfusion (arterial, mean = 100 mm Hg) is sufficient to generate IH and remodeling of human veins. These alterations are reduced in the presence of an external polyester mesh.
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Affiliation(s)
- Alban Longchamp
- Department of Surgery, Brigham and Women's Hospital/Harvard Medical School;
| | - Florent Allagnat
- Laboratory of Experimental Medicine, Department of Medicine, CHUV University Hospital
| | - Xavier Berard
- Department of Vascular Surgery, Pellegrin Hospital, University of Bordeaux
| | - Florian Alonso
- Laboratory of Experimental Medicine, Department of Medicine, CHUV University Hospital
| | | | - Sébastien Deglise
- Department of Thoracic and Vascular Surgery, CHUV University Hospital
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The use of external mesh reinforcement to reduce intimal hyperplasia and preserve the structure of human saphenous veins. Biomaterials 2014; 35:2588-99. [DOI: 10.1016/j.biomaterials.2013.12.041] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/18/2013] [Indexed: 01/14/2023]
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Dubuis C, May L, Alonso F, Luca L, Mylonaki I, Meda P, Delie F, Jordan O, Déglise S, Corpataux JM, Saucy F, Haefliger JA. Atorvastatin-loaded hydrogel affects the smooth muscle cells of human veins. J Pharmacol Exp Ther 2013; 347:574-81. [PMID: 24071735 DOI: 10.1124/jpet.113.208769] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Intimal hyperplasia (IH) is the major cause of stenosis of vein grafts. Drugs such as statins prevent stenosis, but their systemic administration has limited effects. We developed a hyaluronic acid hydrogel matrix, which ensures a controlled release of atorvastatin (ATV) at the site of injury. The release kinetics demonstrated that 100% of ATV was released over 10 hours, independent of the loading concentration of the hydrogel. We investigated the effects of such a delivery on primary vascular smooth muscle cells isolated from human veins. ATV decreased the proliferation, migration, and passage of human smooth muscle cells (HSMCs) across a matrix barrier in a similar dose-dependent (5-10 µM) and time-dependent manner (24-72 hours), whether the drug was directly added to the culture medium or released from the hydrogel. Expression analysis of genes known to be involved in the development of IH demonstrated that the transcripts of both the gap junction protein connexin43 (Cx43) and plasminogen activator inhibitor-1 (PAI-1) were decreased after a 24-48-hour exposure to the hydrogel loaded with ATV, whereas the transcripts of the heme oxygenase (HO-1) and the inhibitor of tissue plasminogen activator were increased. At the protein level, Cx43, PAI-1, and metalloproteinase-9 expression were decreased, whereas HO-1 was upregulated in the presence of ATV. The data demonstrate that ATV released from a hydrogel has effects on HSMCs similar to the drug being freely dissolved in the environment.
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Affiliation(s)
- Céline Dubuis
- Department of Thoracic and Vascular Surgery, University Hospital, Laboratory of Experimental Medicine, Lausanne, Switzerland (C.D., L.M., F.A., S.D., J.-M.C., F.S., J.-A.H.); School of Pharmaceutical Sciences, University of Geneva and University of Lausanne, Geneva, Switzerland (L.L., I.M., F.D., O.J.); and Department of Cell Physiology and Metabolism, University of Geneva, Medical Center, Geneva, Switzerland (P.M.)
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Stack A, Derksen FJ, Sordillo LM, Williams KJ, Stick JA, Brandenberger C, Steibel JP, Robinson NE. Effects of exercise on markers of venous remodeling in lungs of horses. Am J Vet Res 2013; 74:1231-8. [DOI: 10.2460/ajvr.74.9.1231] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Piola M, Prandi F, Bono N, Soncini M, Penza E, Agrifoglio M, Polvani G, Pesce M, Fiore GB. A compact and automated ex vivo vessel culture system for the pulsatile pressure conditioning of human saphenous veins. J Tissue Eng Regen Med 2013; 10:E204-15. [PMID: 23897837 DOI: 10.1002/term.1798] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 04/29/2013] [Accepted: 07/08/2013] [Indexed: 11/05/2022]
Abstract
Saphenous vein (SV) graft disease represents an unresolved problem in coronary artery bypass grafting (CABG). After CABG, a progressive remodelling of the SV wall occurs, possibly leading to occlusion of the lumen, a process termed 'intima hyperplasia' (IH). The investigation of cellular and molecular aspects of IH progression is a primary end-point toward the generation of occlusion-free vessels that may be used as 'life-long' grafts. While animal transplantation models have clarified some of the remodelling factors, the pathology of human SV is far from being understood. This is also due to the lack of devices able to reproduce the altered mechanical load encountered by the SV after CABG. This article describes the design of a novel ex vivo vein culture system (EVCS) capable of replicating the altered pressure pattern experienced by SV after CABG, and reports the results of a preliminary biomechanical conditioning experimental campaign on SV segments. The EVCS applied a CAGB-like pressure (80-120 mmHg) or a venous-like perfusion (3 ml/min, 5 mmHg) conditioning to the SVs, keeping the segments viable in a sterile environment during 7 day culture experiments. After CABG-like pressure conditioning, SVs exhibited a decay of the wall thickness, an enlargement of the luminal perimeter, a rearrangement of the muscle fibres and partial denudation of the endothelium. Considering these preliminary results, the EVCS is a suitable system to study the mechanical attributes of SV graft disease, and its use, combined with a well-designed biological protocol, may be of help in elucidating the cellular and molecular mechanisms involved in SV graft disease.
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Affiliation(s)
- Marco Piola
- Politecnico di Milano, Dipartimento di Elettronica, Informazione e Bioingegneria, Milan, Italy
| | - Francesca Prandi
- Laboratorio di Ingegneria Tissutale Cardiovascolare, Centro Cardiologico Monzino-IRCCS, Milan, Italy
| | - Nina Bono
- Politecnico di Milano, Dipartimento di Elettronica, Informazione e Bioingegneria, Milan, Italy
| | - Monica Soncini
- Politecnico di Milano, Dipartimento di Elettronica, Informazione e Bioingegneria, Milan, Italy
| | - Eleonora Penza
- II Divisione di Cardiochirurgia, Centro Cardiologico Monzino-IRCCS, Milan, Italy
| | - Marco Agrifoglio
- Dipartimento di Scienze Cliniche e di Comunità, Università di Milano, Milan, Italy
| | - Gianluca Polvani
- Dipartimento di Scienze Cliniche e di Comunità, Università di Milano, Milan, Italy
| | - Maurizio Pesce
- Laboratorio di Ingegneria Tissutale Cardiovascolare, Centro Cardiologico Monzino-IRCCS, Milan, Italy
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Berard X, Déglise S, Alonso F, Saucy F, Meda P, Bordenave L, Corpataux JM, Haefliger JA. Role of hemodynamic forces in the ex vivo arterialization of human saphenous veins. J Vasc Surg 2013; 57:1371-82. [PMID: 23351647 DOI: 10.1016/j.jvs.2012.09.041] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 08/31/2012] [Accepted: 09/10/2012] [Indexed: 10/27/2022]
Abstract
BACKGROUND Human saphenous vein grafts are one of the salvage bypass conduits when endovascular procedures are not feasible or fail. Understanding the remodeling process that venous grafts undergo during exposure to arterial conditions is crucial to improve their patency, which is often compromised by intimal hyperplasia. The precise role of hemodynamic forces such as shear stress and arterial pressure in this remodeling is not fully characterized. The aim of this study was to determine the involvement of arterial shear stress and pressure on vein wall remodeling and to unravel the underlying molecular mechanisms. METHODS An ex vivo vein support system was modified for chronic (up to 1 week), pulsatile perfusion of human saphenous veins under controlled conditions that permitted the separate control of arterial shear stress and different arterial pressure (7 mm Hg or 70 mm Hg). RESULTS Veins perfused for 7 days under high pressure (70 mm Hg) underwent significant development of a neointima compared with veins exposed to low pressure (7 mm Hg). These structural changes were associated with altered expression of several molecular markers. Exposure to an arterial shear stress under low pressure increased the expression of matrix metalloproteinase (MMP)-2 and MMP-9 and tissue inhibitor of metalloproteinase (TIMP)-1 at the transcript, protein, and activity levels. This increase was enhanced by high pressure, which also increased TIMP-2 protein expression despite decreased levels of the cognate transcript. In contrast, the expression of plasminogen activator inhibitor-1 increased with shear stress but was not modified by pressure. Levels of the venous marker Eph-B4 were decreased under arterial shear stress, and levels of the arterial marker Ephrin-B2 were downregulated under high-pressure conditions. CONCLUSIONS This model is a valuable tool to identify the role of hemodynamic forces and to decipher the molecular mechanisms leading to failure of human saphenous vein grafts. Under ex vivo conditions, arterial perfusion is sufficient to activate the remodeling of human veins, a change that is associated with the loss of specific vein markers. Elevation of pressure generates intimal hyperplasia, even though veins do not acquire arterial markers. CLINICAL RELEVANCE The pathological remodeling of the venous wall, which leads to stenosis and ultimately graft failure, is the main limiting factor of human saphenous vein graft bypass. This remodeling is due to the hemodynamic adaptation of the vein to the arterial environment and cannot be prevented by conventional therapy. To develop a more targeted therapy, a better understanding of the molecular mechanisms involved in intimal hyperplasia is essential, which requires the development of ex vivo models of chronic perfusion of human veins.
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Affiliation(s)
- Xavier Berard
- Department of Vascular Surgery, Pellegrin Hospital, University of Bordeaux, Bordeaux, France
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Dummler S, Eichhorn S, Tesche C, Schreiber U, Voss B, Deutsch MA, Hauner H, Lahm H, Lange R, Krane M. Pulsatile ex vivo perfusion of human saphenous vein grafts under controlled pressure conditions increases MMP-2 expression. Biomed Eng Online 2011; 10:62. [PMID: 21777461 PMCID: PMC3148203 DOI: 10.1186/1475-925x-10-62] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Accepted: 07/21/2011] [Indexed: 11/16/2022] Open
Abstract
Background The use of human saphenous vein grafts (HSVGs) as a bypass conduit is a standard procedure in the treatment of coronary artery disease while their early occlusion remains a major problem. Methods We have developed an ex vivo perfusion system, which uses standardized and strictly controlled hemodynamic parameters for the pulsatile and non-static perfusion of HSVGs to guarantee a reliable analysis of molecular parameters under different pressure conditions. Cell viability of HSVGs (n = 12) was determined by the metabolic conversion of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) into a purple formazan dye. Results Under physiological flow rates (10 mmHg) HSVGs remained viable for two weeks. Their exposure to arterial conditions (100 mmHg) was possible for one week without important reduction in viability. Baseline expression of matrix metalloproteinase-2 (MMP-2) after venous perfusion (2.2 ± 0.5, n = 5) was strongly up-regulated after exposure to arterial conditions for three days (19.8 ± 4.3) or five days (23.9 ± 6.1, p < 0.05). Zymographic analyses confirmed this increase on the protein level. Our results suggest that expression and activity of MMP-2 are strongly increased after exposure of HSVGs to arterial hemodynamic conditions compared to physiological conditions. Conclusion Therefore, our system might be helpful to more precisely understand the molecular mechanisms leading to an early failure of HSVGs.
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Affiliation(s)
- Sara Dummler
- German Heart Center Munich at the Technische Universität München, Department of Cardiovascular Surgery, Lazarettstrasse 36, D-80636 Munich, Germany.
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