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Massaro MS, Kochová P, Pálek R, Rosendorf J, Červenková L, Dahmen U, Liška V, Moulisová V. Decellularization of Porcine Carotid Arteries: From the Vessel to the High-Quality Scaffold in Five Hours. Front Bioeng Biotechnol 2022; 10:833244. [PMID: 35651544 PMCID: PMC9150822 DOI: 10.3389/fbioe.2022.833244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 04/06/2022] [Indexed: 11/13/2022] Open
Abstract
The use of biologically derived vessels as small-diameter vascular grafts in vascular diseases is currently intensely studied. Vessel decellularization provides a biocompatible scaffold with very low immunogenicity that avoids immunosuppression after transplantation. Good scaffold preservation is important as it facilitates successful cell repopulation. In addition, mechanical characteristics have to be carefully evaluated when the graft is intended to be used as an artery due to the high pressures the vessel is subjected to. Here, we present a new and fast decellularization protocol for porcine carotid arteries, followed by investigation of the quality of obtained vessel scaffolds in terms of maintenance of important extracellular matrix components, mechanical resistance, and compatibility with human endothelial cells. Our results evidence that our decellularization protocol minimally alters both the presence of scaffold proteins and their mechanical behavior and human endothelial cells could adhere to the scaffold in vitro. We conclude that if a suitable protocol is used, a high-quality decellularized arterial scaffold of non-human origin can be promptly obtained, having a great potential to be recellularized and used as an arterial graft in transplantation medicine.
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Affiliation(s)
| | - Petra Kochová
- New Technologies for Information Society-NTIS, University of West Bohemia, Pilsen, Czechia
| | - Richard Pálek
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
- Department of Surgery, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
| | - Jáchym Rosendorf
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
- Department of Surgery, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
| | - Lenka Červenková
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
| | - Uta Dahmen
- Experimental Transplantation Surgery, Department of General, Visceral and Vascular Surgery, University Hospital Jena, Jena, Germany
| | - Václav Liška
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
- Department of Surgery, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
| | - Vladimíra Moulisová
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
- *Correspondence: Vladimíra Moulisová,
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Kemper P, Nauleau P, Karageorgos G, Weber R, Kwon N, Szabolcs M, Konofagou E. Feasibility of longitudinal monitoring of atherosclerosis with pulse wave imaging in a swine model. Physiol Meas 2021; 42:10.1088/1361-6579/ac290f. [PMID: 34551396 PMCID: PMC8733748 DOI: 10.1088/1361-6579/ac290f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 09/22/2021] [Indexed: 12/30/2022]
Abstract
Objective.Atherosclerosis is a vascular disease characterized by compositional and mechanical changes in the arterial walls that lead to a plaque buildup. Depending on its geometry and composition, a plaque can ruptured and cause stroke, ischemia or infarction. Pulse wave imaging (PWI) is an ultrasound-based technique developed to locally quantify the stiffness of arteries. This technique has shown promising results when applied to patients. The objective of this study is to assess the capability of PWI to monitor the disease progression in a swine model that mimics human pathology.Approach.The left common carotid of three hypercholesterolemic Wisconsin miniature swines, fed an atherogenic diet, was ligated. Ligated and contralateral carotids were imaged once a month over 9 months, at a high-frame-rate, with a 5-plane wave compounding sequence and a 5 MHz linear array. Each acquisition was repeated after probe repositioning to evaluate the reproducibility. Wall displacements were estimated from the beamformed RF-data and were arranged as spatiotemporal maps depicting the wave propagation. The pulse wave velocity (PWV) estimated by tracking the 50% upstroke of the wave was converted in compliance using the Bramwell-Hill model. At the termination of the experiment, the carotids were extracted for histology analysis.Main results.PWI was able to monitor the evolution of compliance in both carotids of the animals. Reproducibility was demonstrated as the difference of PWV between cardiac cycles was similar to the difference between acquisitions (9.04% versus 9.91%). The plaque components were similar to the ones usually observed in patients. Each animal presented a unique pattern of compliance progression, which was confirmed by the plaque composition observed histologically.Significance.This study provides important insights on the vascular wall stiffness progression in an atherosclerotic swine model. It therefore paves the way for a thorough longitudinal study that examines the role of stiffness in both the plaque formation and plaque progression.
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Affiliation(s)
- Paul Kemper
- Department of Biomedical Engineering, Columbia University, New York, NY, United States of America
| | - Pierre Nauleau
- Department of Biomedical Engineering, Columbia University, New York, NY, United States of America
| | - Grigorios Karageorgos
- Department of Biomedical Engineering, Columbia University, New York, NY, United States of America
| | - Rachel Weber
- Department of Biomedical Engineering, Columbia University, New York, NY, United States of America
| | - Nancy Kwon
- Department of Biomedical Engineering, Columbia University, New York, NY, United States of America
| | - Matthias Szabolcs
- Department of Pathology and Cell Biology, Columbia University, New York, NY, United States of America
| | - Elisa Konofagou
- Department of Biomedical Engineering, Columbia University, New York, NY, United States of America
- Department of Radiology, Columbia University, New York, NY, United States of America
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3
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Clark-Patterson GL, Roy S, Desrosiers L, Knoepp LR, Sen A, Miller KS. Role of fibulin-5 insufficiency and prolapse progression on murine vaginal biomechanical function. Sci Rep 2021; 11:20956. [PMID: 34697337 PMCID: PMC8546087 DOI: 10.1038/s41598-021-00351-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 08/31/2021] [Indexed: 02/04/2023] Open
Abstract
The vagina plays a critical role in supporting the pelvic organs and loss of support leads to pelvic organ prolapse. It is unknown what microstructural changes influence prolapse progression nor how decreased elastic fibers contributes to vaginal remodeling and smooth muscle contractility. The objective for this study was to evaluate the effect of fibulin-5 haploinsufficiency, and deficiency with progressive prolapse on the biaxial contractile and biomechanical function of the murine vagina. Vaginas from wildtype (n = 13), haploinsufficient (n = 13), and deficient mice with grade 1 (n = 9) and grade 2 or 3 (n = 9) prolapse were explanted for biaxial contractile and biomechanical testing. Multiaxial histology (n = 3/group) evaluated elastic and collagen fiber microstructure. Western blotting quantified protein expression (n = 6/group). A one-way ANOVA or Kruskal-Wallis test evaluated statistical significance. Pearson's or Spearman's test determined correlations with prolapse grade. Axial contractility decreased with fibulin-5 deficiency and POP (p < 0.001), negatively correlated with prolapse grade (ρ = - 0.80; p < 0.001), and positively correlated with muscularis elastin area fraction (ρ = - 0.78; p = 0.004). Circumferential (ρ = 0.71; p < 0.001) and axial (ρ = 0.69; p < 0.001) vaginal wall stresses positively correlated with prolapse grade. These findings demonstrated that fibulin-5 deficiency and prolapse progression decreased vaginal contractility and increased vaginal wall stress. Future work is needed to better understand the processes that contribute to prolapse progression in order to guide diagnostic, preventative, and treatment strategies.
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Affiliation(s)
| | - Sambit Roy
- Department of Animal Sciences, Reproductive and Developmental Sciences Program, Michigan State University, East Lansing, 48824, USA
| | - Laurephile Desrosiers
- Department of Female Pelvic Medicine and Reconstructive Surgery, University of Queensland Ochsner Clinical School, New Orleans, 70121, USA
| | - Leise R Knoepp
- Department of Female Pelvic Medicine and Reconstructive Surgery, University of Queensland Ochsner Clinical School, New Orleans, 70121, USA
| | - Aritro Sen
- Department of Animal Sciences, Reproductive and Developmental Sciences Program, Michigan State University, East Lansing, 48824, USA
| | - Kristin S Miller
- Department of Biomedical Engineering, Tulane University, New Orleans, 70118, USA.
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Kim SH, Monticone RE, McGraw KR, Wang M. Age-associated proinflammatory elastic fiber remodeling in large arteries. Mech Ageing Dev 2021; 196:111490. [PMID: 33839189 DOI: 10.1016/j.mad.2021.111490] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/24/2021] [Accepted: 04/05/2021] [Indexed: 12/12/2022]
Abstract
Elastic fibers are the main components of the extracellular matrix of the large arterial wall. Elastic fiber remodeling is an intricate process of synthesis and degradation of the core elastin protein and microfibrils accompanied by the assembly and disassembly of accessory proteins. Age-related morphological, structural, and functional proinflammatory remodeling within the elastic fiber has a profound effect upon the integrity, elasticity, calcification, amyloidosis, and stiffness of the large arterial wall. An age-associated increase in arterial stiffness is a major risk factor for the pathogenesis of diseases of the large arteries such as hypertensive and atherosclerotic vasculopathy. This mini review is an update on the key molecular, cellular, functional, and structural mechanisms of elastic fiber proinflammatory remodeling in large arteries with aging. Targeting structural and functional integrity of the elastic fiber may be an effective approach to impede proinflammatory arterial remodeling with advancing age.
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Affiliation(s)
- Soo Hyuk Kim
- Laboratory of Cardiovascular Science, Intramural Research Program, National Institution on Aging, National Institutes of Health, Biomedical Research Center (BRC), 251 Bayview Boulevard, Baltimore, MD, 21224, USA
| | - Robert E Monticone
- Laboratory of Cardiovascular Science, Intramural Research Program, National Institution on Aging, National Institutes of Health, Biomedical Research Center (BRC), 251 Bayview Boulevard, Baltimore, MD, 21224, USA
| | - Kimberly R McGraw
- Laboratory of Cardiovascular Science, Intramural Research Program, National Institution on Aging, National Institutes of Health, Biomedical Research Center (BRC), 251 Bayview Boulevard, Baltimore, MD, 21224, USA
| | - Mingyi Wang
- Laboratory of Cardiovascular Science, Intramural Research Program, National Institution on Aging, National Institutes of Health, Biomedical Research Center (BRC), 251 Bayview Boulevard, Baltimore, MD, 21224, USA.
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Navarrete A, Chen Z, Aranda P, Poblete D, Utrera A, García-Herrera CM, Gonzalez-Candia A, Beñaldo FA, Ebensperger G, Reyes RV, Herrera EA, Llanos AJ. Study of the Effect of Treatment With Atrial Natriuretic Peptide (ANP) and Cinaciguat in Chronic Hypoxic Neonatal Lambs on Residual Strain and Microstructure of the Arteries. Front Bioeng Biotechnol 2020; 8:590488. [PMID: 33244466 PMCID: PMC7683788 DOI: 10.3389/fbioe.2020.590488] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 10/21/2020] [Indexed: 01/01/2023] Open
Abstract
In this study, we assessed the effects of Atrial Natriuretic Peptide (ANP) and Cinaciguat, as experimental medicines to treat neonatal lambs exposed to chronic hypoxic conditions. To compare the different treatments, the mechanical responses of aorta, carotid, and femoral arterial walls were analyzed by means of axial pre-stretch and ring-opening tests, through a study with n = 6 animals for each group analyzed. The axial pre-stretch test measures the level of shortening in different zones of the arteries when extracted from lambs, while the ring-opening test is used to quantify the degree of residual circumferential deformation in a given zone of an artery. In addition, histological studies were carried out to measure elastin, collagen, and smooth muscle cell (SMC) nuclei densities, both in control and treated groups. The results show that mechanical response is related with histological results, specifically in the proximal abdominal aorta (PAA) and distal carotid zones (DCA), where the cell nuclei content is related to a decrease of residual deformations. The opening angle and the elastic fibers of the aorta artery were statistically correlated (p < 0.05). Specifically, in PAA zone, there are significant differences of opening angle and cell nuclei density values between control and treated groups (p-values to opening angle: Control-ANP = 2 ⋅ 10-2, Control-Cinaciguat = 1 ⋅ 10-2; p-values to cell nuclei density: Control-ANP = 5 ⋅ 10-4, Control-Cinaciguat = 2 ⋅ 10-2). Respect to distal carotid zone (DCA), significant differences between Control and Cinaciguat groups were observed to opening angle (p-value = 4 ⋅ 10-2), and cell nuclei density (p-value = 1 ⋅ 10-2). Our findings add evidence that medical treatments may have effects on the mechanical responses of arterial walls and should be taken into account when evaluating the complete medical outcome.
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Affiliation(s)
- Alvaro Navarrete
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Zhuoming Chen
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Pedro Aranda
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Daniel Poblete
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | - Andrés Utrera
- Departamento de Ingeniería Mecánica, Universidad de Santiago de Chile, Santiago, Chile
| | | | - Alejandro Gonzalez-Candia
- Instituto de Ciencias de la Salud, Universidad de O’Higgins, Rancagua, Chile
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
| | - Felipe A. Beñaldo
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
| | - German Ebensperger
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
| | - Roberto V. Reyes
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
- International Center for Andean Studies (INCAS), Universidad de Chile, Santiago, Chile
| | - Emilio A. Herrera
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
- International Center for Andean Studies (INCAS), Universidad de Chile, Santiago, Chile
| | - Anibal J. Llanos
- Pathophysiology Program, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago, Chile
- International Center for Andean Studies (INCAS), Universidad de Chile, Santiago, Chile
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6
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Reavette RM, Sherwin SJ, Tang M, Weinberg PD. Comparison of arterial wave intensity analysis by pressure-velocity and diameter-velocity methods in a virtual population of adult subjects. Proc Inst Mech Eng H 2020; 234:1260-1276. [PMID: 32650691 PMCID: PMC7802055 DOI: 10.1177/0954411920926094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 03/22/2020] [Indexed: 12/21/2022]
Abstract
Pressure-velocity-based analysis of arterial wave intensity gives clinically relevant information about the performance of the heart and vessels, but its utility is limited because accurate pressure measurements can only be obtained invasively. Diameter-velocity-based wave intensity can be obtained noninvasively using ultrasound; however, due to the nonlinear relationship between blood pressure and arterial diameter, the two wave intensities might give disparate clinical indications. To test the magnitude of the disagreement, we have generated an age-stratified virtual population to investigate how the two dominant nonlinearities viscoelasticity and strain-stiffening cause the two formulations to differ. We found strong agreement between the pressure-velocity and diameter-velocity methods, particularly for the systolic wave energy, the ratio between systolic and diastolic wave heights, and older subjects. The results are promising regarding the introduction of noninvasive wave intensities in the clinic.
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Affiliation(s)
- Ryan M Reavette
- Department of Bioengineering, Imperial College London, London, UK
| | | | - Mengxing Tang
- Department of Bioengineering, Imperial College London, London, UK
| | - Peter D Weinberg
- Department of Bioengineering, Imperial College London, London, UK
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Burkert J, Kochová P, Tonar Z, Cimrman R, Blassová T, Jashari R, Fiala R, Špatenka J. The time has come to extend the expiration limit of cryopreserved allograft heart valves. Cell Tissue Bank 2020; 22:161-184. [PMID: 32583302 DOI: 10.1007/s10561-020-09843-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/13/2020] [Indexed: 12/12/2022]
Abstract
Despite the wide choice of commercial heart valve prostheses, cryopreserved semilunar allograft heart valves (C-AHV) are required, and successfully transplanted in selected groups of patients. The expiration limit (EL) criteria have not been defined yet. Most Tissue Establishments (TE) use the EL of 5 years. From physiological, functional, and surgical point of view, the morphology and mechanical properties of aortic and pulmonary roots represent basic features limiting the EL of C-AHV. The aim of this work was to review methods of AHV tissue structural analysis and mechanical testing from the perspective of suitability for EL validation studies. Microscopic structure analysis of great arterial wall and semilunar leaflets tissue should clearly demonstrate cells as well as the extracellular matrix components by highly reproducible and specific histological staining procedures. Quantitative morphometry using stereological grids has proved to be effective, as the exact statistics was feasible. From mechanical testing methods, tensile test was the most suitable. Young's moduli of elasticity, ultimate stress and strain were shown to represent most important AHV tissue mechanical characteristics, suitable for exact statistical analysis. C-AHV are prepared by many different protocols, so as each TE has to work out own EL for C-AHV.
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Affiliation(s)
- Jan Burkert
- Department of Transplantation and Tissue Banking, Czech National Allograft Heart Valve Bank, Department of Cardiovascular Surgery, Motol University Hospital, and Second Faculty of Medicine Charles University in Prague, V Úvalu 84, 150 06, Prague, Czech Republic
| | - Petra Kochová
- Department of Transplantation and Tissue Banking, Czech National Allograft Heart Valve Bank, Department of Cardiovascular Surgery, Motol University Hospital, and Second Faculty of Medicine Charles University in Prague, V Úvalu 84, 150 06, Prague, Czech Republic. .,NTIS - New Technologies for the Information Society, Faculty of Applied Sciences, University of West Bohemia, Technická 8, Pilsen, Czech Republic.
| | - Zbyněk Tonar
- NTIS - New Technologies for the Information Society, Faculty of Applied Sciences, University of West Bohemia, Technická 8, Pilsen, Czech Republic.,Department of Histology and Embryology, Biomedical Centre, Faculty of Medicine in Pilsen, Charles University in Prague, Karlovarská 48, 301 66, Pilsen, Czech Republic
| | - Robert Cimrman
- NTIS - New Technologies for the Information Society, Faculty of Applied Sciences, University of West Bohemia, Technická 8, Pilsen, Czech Republic
| | - Tereza Blassová
- Department of Histology and Embryology, Biomedical Centre, Faculty of Medicine in Pilsen, Charles University in Prague, Karlovarská 48, 301 66, Pilsen, Czech Republic
| | - Ramadan Jashari
- European Homograft Bank, Saint-Jean Clinic, Rue du Meridien 100, 1210, Brussels, Belgium
| | - Radovan Fiala
- Department of Transplantation and Tissue Banking, Czech National Allograft Heart Valve Bank, Department of Cardiovascular Surgery, Motol University Hospital, and Second Faculty of Medicine Charles University in Prague, V Úvalu 84, 150 06, Prague, Czech Republic
| | - Jaroslav Špatenka
- Department of Transplantation and Tissue Banking, Czech National Allograft Heart Valve Bank, Department of Cardiovascular Surgery, Motol University Hospital, and Second Faculty of Medicine Charles University in Prague, V Úvalu 84, 150 06, Prague, Czech Republic
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8
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De Munck DG, Leloup AJA, De Meyer GRY, Martinet W, Fransen P. Defective autophagy in vascular smooth muscle cells increases passive stiffness of the mouse aortic vessel wall. Pflugers Arch 2020; 472:1031-1040. [PMID: 32488322 DOI: 10.1007/s00424-020-02408-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/28/2020] [Accepted: 05/22/2020] [Indexed: 12/17/2022]
Abstract
Aging and associated progressive arterial stiffening are both important predictors for the development of cardiovascular diseases. Recent evidence showed that autophagy, a catabolic cellular mechanism responsible for nutrient recycling, plays a major role in the physiology of vascular cells such as endothelial cells and vascular smooth muscle cells (VSMCs). Moreover, several autophagy inducing compounds are effective in treating arterial stiffness. Yet, a direct link between VSMC autophagy and arterial stiffness remains largely unidentified. Therefore, we investigated the effects of a VSMC-specific deletion of the essential autophagy-related gene Atg7 in young mice (3.5 months) (Atg7F/F SM22α-Cre+ mice) on the biomechanical properties of the aorta, using an in-house developed Rodent Oscillatory Tension Set-up to study Arterial Compliance (ROTSAC). Aortic segments of Atg7F/F SM22α-Cre+ mice displayed attenuated compliance and higher arterial stiffness, which was more evident at higher distention pressures. Passive aortic wall remodeling, rather than differences in VSMC tone, is responsible for these phenomena, since differences in compliance and stiffness between Atg7+/+ SM22α-Cre+ and Atg7F/F SM22α-Cre+ aortas were more pronounced when VSMCs were completely relaxed by the addition of exogenous nitric oxide. These observations are supported by histological data showing a 13% increase in medial wall thickness and a 14% decrease in elastin along with elevated elastin fragmentation. In addition, expression of the calcium-binding protein S100A4, which is linked to matrix remodeling, was elevated in aortic segments of Atg7F/F SM22α-Cre+ mice. Overall, these findings illustrate that autophagy exerts a crucial role in defining arterial wall compliance.
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Affiliation(s)
- Dorien G De Munck
- Laboratory of Physiopharmacology, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium
| | - Arthur J A Leloup
- Laboratory of Physiopharmacology, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium
| | - Guido R Y De Meyer
- Laboratory of Physiopharmacology, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium
| | - Wim Martinet
- Laboratory of Physiopharmacology, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium
| | - Paul Fransen
- Laboratory of Physiopharmacology, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.
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Wang M, Monticone RE, McGraw KR. Proinflammation, profibrosis, and arterial aging. Aging Med (Milton) 2020; 3:159-168. [PMID: 33103036 PMCID: PMC7574637 DOI: 10.1002/agm2.12099] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 02/10/2020] [Accepted: 02/11/2020] [Indexed: 12/18/2022] Open
Abstract
Aging is a major risk factor for quintessential cardiovascular diseases, which are closely related to arterial proinflammation. The age-related alterations of the amount, distribution, and properties of the collagen fibers, such as cross-links and degradation in the arterial wall, are the major sequelae of proinflammation. In the aging arterial wall, collagen types I, II, and III are predominant, and are mainly produced by stiffened vascular smooth muscle cells (VSMCs) governed by proinflammatory signaling, leading to profibrosis. Profibrosis is regulated by an increase in the proinflammatory molecules angiotensin II, milk fat globule-EGF-VIII, and transforming growth factor-beta 1 (TGF-β1) signaling and a decrease in the vasorin signaling cascade. The release of these proinflammatory factors triggers the activation of matrix metalloproteinase type II (MMP-2) and activates profibrogenic TGF-β1 signaling, contributing to profibrosis. The age-associated increase in activated MMP-2 cleaves latent TGF-β and subsequently increases TGF-β1 activity leading to collagen deposition in the arterial wall. Furthermore, a blockade of the proinflammatory signaling pathway alleviates the fibrogenic signaling, reduces profibrosis, and prevents arterial stiffening with aging. Thus, age-associated proinflammatory-profibrosis coupling is the underlying molecular mechanism of arterial stiffening with advancing age.
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Affiliation(s)
- Mingyi Wang
- Laboratory of Cardiovascular Science National Institute on Aging National Institutes of Health Baltimore Maryland
| | - Robert E Monticone
- Laboratory of Cardiovascular Science National Institute on Aging National Institutes of Health Baltimore Maryland
| | - Kimberly R McGraw
- Laboratory of Cardiovascular Science National Institute on Aging National Institutes of Health Baltimore Maryland
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Yan S, Napiwocki B, Xu Y, Zhang J, Zhang X, Wang X, Crone WC, Li Q, Turng LS. Wavy small-diameter vascular graft made of eggshell membrane and thermoplastic polyurethane. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 107:110311. [PMID: 31761197 PMCID: PMC6905500 DOI: 10.1016/j.msec.2019.110311] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 09/17/2019] [Accepted: 10/12/2019] [Indexed: 12/17/2022]
Abstract
In this study, a small-diameter, double-layered eggshell membrane/thermoplastic polyurethane (ESM/TPU) vascular graft with a wavy structure was developed. The avian eggshell membrane, a fibrous structure similar to the extracellular matrix (ECM), has the potential to yield rapid endothelialization in vitro. The dopamine and heparin modification of the ESM surface not only promoted human umbilical vein endothelial cell (HUVEC) proliferation via cytocompatibility assessment, but also improved its anticoagulation properties as verified in platelet adhesion tests. The biomimetic mechanical properties of the vascular graft were provided by the elastic TPU fibers via electrospinning using a wavy cross-section rotating collector. The advantage of combining these two materials is to make use of the bioactivity of ESM as the internal membrane and the tunable mechanical properties of TPU as the external layer. The circumferentially wavy structure of the vascular graft produced a toe region in the non-linear section of the stress-strain curve similar to that of natural blood vessels. The ESM/TPU graft's circumferential ultimate strength was 2.57 MPa, its strain was 339% mm/mm, and its toe region was found to be around 20% mm/mm. Cyclical tension tests showed that the vascular graft could maintain good mechanical properties and showed no structural damage under repeated extension tests.
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Affiliation(s)
- Shujie Yan
- School of Mechanics and Engineering Science, Zhengzhou University, Zhengzhou, China; National Center for International Research of Micro-Nano Molding Technology Zhengzhou University, Zhengzhou, China; Polymer Engineering Center, Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI, USA; Wisconsin Institute for Discovery University of Wisconsin-Madison, Madison, WI, USA
| | - Brett Napiwocki
- Wisconsin Institute for Discovery University of Wisconsin-Madison, Madison, WI, USA
| | - Yiyang Xu
- School of Mechanics and Engineering Science, Zhengzhou University, Zhengzhou, China; National Center for International Research of Micro-Nano Molding Technology Zhengzhou University, Zhengzhou, China; Polymer Engineering Center, Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI, USA; Wisconsin Institute for Discovery University of Wisconsin-Madison, Madison, WI, USA
| | - Jue Zhang
- Morgridge Institute for Research, Madison, WI, USA
| | - Xiang Zhang
- School of Mechanics and Engineering Science, Zhengzhou University, Zhengzhou, China; National Center for International Research of Micro-Nano Molding Technology Zhengzhou University, Zhengzhou, China
| | - Xiaofeng Wang
- School of Mechanics and Engineering Science, Zhengzhou University, Zhengzhou, China; National Center for International Research of Micro-Nano Molding Technology Zhengzhou University, Zhengzhou, China
| | - Wendy C Crone
- Wisconsin Institute for Discovery University of Wisconsin-Madison, Madison, WI, USA
| | - Qian Li
- School of Mechanics and Engineering Science, Zhengzhou University, Zhengzhou, China; National Center for International Research of Micro-Nano Molding Technology Zhengzhou University, Zhengzhou, China.
| | - Lih-Sheng Turng
- Polymer Engineering Center, Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI, USA; Wisconsin Institute for Discovery University of Wisconsin-Madison, Madison, WI, USA.
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11
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Tomášek P, Tonar Z, Grajciarová M, Kural T, Turek D, Horáková J, Pálek R, Eberlová L, Králíčková M, Liška V. Histological mapping of porcine carotid arteries - An animal model for the assessment of artificial conduits suitable for coronary bypass grafting in humans. Ann Anat 2019; 228:151434. [PMID: 31704146 DOI: 10.1016/j.aanat.2019.151434] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 09/12/2019] [Accepted: 10/11/2019] [Indexed: 11/16/2022]
Abstract
BACKGROUND Using animal models in experimental medicine requires mapping of their anatomical variability. Porcine common carotid arteries (CCA) are often preferred for the preclinical testing of vascular grafts due to their anatomical and physiological similarity to human small-diameter arteries. Comparing the microscopic structure of animal model organs to their human counterparts reveals the benefits and limitations of translational medicine. METHODS Using quantitative histology and stereology, we performed an extensive mapping of the regional proximodistal differences in the fractions of elastin, collagen, and smooth muscle actin as well as the intima-media and wall thicknesses among 404 segments (every 1 cm) of porcine CCAs collected from male and female pigs (n = 21). We also compared the microscopic structure of porcine CCAs with segments of human coronary arteries and one of the preferred arterial conduits used for the coronary artery bypass grafting (CABG), namely, the internal thoracic artery (ITA) (n = 21 human cadavers). RESULTS The results showed that the histological structure of left and right porcine CCA can be considered equivalent, provided that gross anatomical variations of the regular branching patterns are excluded. The proximal elastic carotid (51.2% elastin, 4.2% collagen, and 37.2% actin) transitioned to more muscular middle segments (23.5% elastin, 4.9% collagen, 54.3% actin) at the range of 2-3 centimeters and then to even more muscular distal segments (17.2% elastin, 4.9% collagen, 64.0% actin). The resulting morphometric data set shows the biological variability of the artery and is made available for biomechanical modeling and for performing a power analysis and calculating the minimum number of samples per group when planning further experiments with this widely used large animal model. CONCLUSIONS Comparison of porcine carotids with human coronary arteries and ITA revealed the benefits and the limitations of using porcine CCAs as a valid model for testing bioengineered small-diameter CABG vascular conduits. Morphometry of human coronary arteries and ITA provided more realistic data for tailoring multilayered artificial vascular prostheses and the ranges of values within which the conduits should be tested in the future. Despite their limitations, porcine CCAs remain a widely used and well-characterized large animal model that is available for a variety of experiments in vascular surgery.
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Affiliation(s)
- Petr Tomášek
- Department of Histology and Embryology and Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Karlovarska 48, 301 66 Pilsen, Czech Republic; Department of Forensic Medicine, Second Faculty of Medicine, Charles University and Na Bulovce Hospital, Budinova 2, 180 81 Prague, Czech Republic
| | - Zbyněk Tonar
- Department of Histology and Embryology and Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Karlovarska 48, 301 66 Pilsen, Czech Republic.
| | - Martina Grajciarová
- Department of Histology and Embryology and Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Karlovarska 48, 301 66 Pilsen, Czech Republic
| | - Tomáš Kural
- Department of Histology and Embryology and Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Karlovarska 48, 301 66 Pilsen, Czech Republic
| | - Daniel Turek
- First Faculty of Medicine, Charles University in Prague, Katerinska 32, 121 08 Prague 2, Czech Republic; Department of Cardiac Surgery, Institute for Clinical and Experimental Medicine, Videnska 1958/9, 140 21 Prague, Czech Republic
| | - Jana Horáková
- Department of Nonwovens and Nanofibrous Materials, Faculty of Textile Engineering, Technical University of Liberec, Studentska 2, 461 17 Liberec, Czech Republic
| | - Richard Pálek
- Department of Surgery and Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Husova 3, 306 05 Pilsen, Czech Republic
| | - Lada Eberlová
- Department of Anatomy, Faculty of Medicine in Pilsen, Charles University, Karlovarska 48, 301 66 Pilsen, Czech Republic
| | - Milena Králíčková
- Department of Histology and Embryology and Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Karlovarska 48, 301 66 Pilsen, Czech Republic
| | - Václav Liška
- Department of Surgery and Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Husova 3, 306 05 Pilsen, Czech Republic
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12
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Smooth muscle phenotype in aortic diseases: Are there other histopathological markers besides contractile myofibrils? Anatol J Cardiol 2019; 19:17-18. [PMID: 29339695 PMCID: PMC5864784 DOI: 10.14744/anatoljcardiol.2017.25927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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13
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Birzle AM, Hobrack SMK, Martin C, Uhlig S, Wall WA. Constituent-specific material behavior of soft biological tissue: experimental quantification and numerical identification for lung parenchyma. Biomech Model Mechanobiol 2019; 18:1383-1400. [PMID: 31053928 DOI: 10.1007/s10237-019-01151-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 04/17/2019] [Indexed: 12/14/2022]
Abstract
In this study, we present a method to experimentally quantify and numerically identify the constituent-specific material behavior of soft biological tissues. This allows the clear identification of the individual contributions of major load-bearing constituents and their interactions in the constitutive law. While the overall approach is applicable for many tissues, here it will be presented for the identification of a sophisticated constituent-specific material model of viable lung parenchyma. This material model will help to better model the effects of various lung diseases that feature altered fiber content in the lungs, such as emphysema or fibrosis. To experimentally quantify the mechanical properties of collagen, elastin, collagen-elastin-fiber interactions, and ground substance, we examined 18 collagenase and elastase treated rat lung parenchymal slices. The mechanical contributions of the collagen and elastin fibers in the living tissue were inferred from uniaxial tension tests comparing the behavior before and after the selective digestion of the respective fibers. In order to also obtain the mechanical influence of the ground substance, we consecutively treated the samples with both proteases. Collagen and elastin fibers are morphologically interconnected. Thus, a mechanical interaction between these fibers appears likely, but has not yet been experimentally verified. In this paper, we propose an experimental method to quantitatively assess the mechanical behavior of these collagen-elastin-fiber interactions. Based on our experiments, we have identified individual material models within a nonlinear continuum mechanics framework for each load-bearing component via an inverse analysis. The proposed constituent-specific material law can be incorporated into computational models of the respiratory system to simulate and even predict the behavior and alteration of the individual constituents and their effect on the whole respiratory system during normal and artificial breathing, in particular in the case of diseases that alter the fibers in the tissue.
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Affiliation(s)
- Anna M Birzle
- Institute for Computational Mechanics, Technical University of Munich, Boltzmannstr. 15, 85748, Garching b. Munich, Germany.
| | - Sophie M K Hobrack
- Institute for Computational Mechanics, Technical University of Munich, Boltzmannstr. 15, 85748, Garching b. Munich, Germany.,Munich University of Applied Sciences, Lothstr. 34, 80335, Munich, Germany
| | - Christian Martin
- Institute of Pharmacology and Toxicology, RWTH Aachen University, Wendlingweg 2, 52074, Aachen, Germany
| | - Stefan Uhlig
- Institute of Pharmacology and Toxicology, RWTH Aachen University, Wendlingweg 2, 52074, Aachen, Germany
| | - Wolfgang A Wall
- Institute for Computational Mechanics, Technical University of Munich, Boltzmannstr. 15, 85748, Garching b. Munich, Germany
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14
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Fiala R, Kochová P, Kubíková T, Cimrman R, Tonar Z, Špatenka J, Fabián O, Burkert J. Mechanical and structural properties of human aortic and pulmonary allografts do not deteriorate in the first 10 years of cryopreservation and storage in nitrogen. Cell Tissue Bank 2019; 20:221-241. [PMID: 30903411 DOI: 10.1007/s10561-019-09762-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 03/13/2019] [Indexed: 11/22/2022]
Abstract
The aortic and pulmonary allograft heart valves (AHV) are used in the cardiac surgery for replacing the impaired semilunar valves. They are harvested from donor hearts and cryostored in tissue banks. The expiration period was set to 5 years arbitrarily. We hypothesized that their mechanical and structural properties do not deteriorate after this period. A total of 64 human AHV (31 aortic and 33 pulmonary) of different length of cryopreservation (fresh, 0-5, 5-10, over 10 years) were sampled to different tissue strips (artery, leaflet, ventriculo-arterial junction) and tested by tensile test with loading velocity 10 mm/min until tissue rupture. Neighbouring regions of tissue were processed histologically and evaluated for elastin and collagen area fraction. The results were evaluated statistically. In aortic AHV, the physical deformation response of wall samples to stress did not changed significantly neither during the process of cryopreservation nor during the first 10 years of storage. In pulmonary AHV, the ultimate strain dropped after 5 years of cryopreservation indicating that pulmonary artery was significantly less deformable at the time of rupture. On the other hand, the ultimate stress was equal during the first 10 years of cryostorage. The changes in collagen and elastin amount in the tissue samples were not associated with mechanical impairment. Neither elasticity, stiffness and solidity nor morphology of aortic and pulmonary AHV did not change reasonably with cryopreservation and in the first 10 years of cryostorage. This evidence suggests that the expiration period might be extended in the future.
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Affiliation(s)
- Radovan Fiala
- Department of Cardiovascular Surgery, Motol University Hospital, Second Faculty of Medicine, Charles University in Prague, V Úvalu 84, 150 06, Prague, Czech Republic.
| | - Petra Kochová
- Department of Cardiovascular Surgery, Motol University Hospital, Second Faculty of Medicine, Charles University in Prague, V Úvalu 84, 150 06, Prague, Czech Republic.,NTIS - New Technologies for the Information Society, Faculty of Applied Sciences, University of West Bohemia, Technická 8, Pilsen, Czech Republic
| | - Tereza Kubíková
- Department of Histology and Embryology, Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Karlovarská 48, 301 66, Pilsen, Czech Republic
| | - Robert Cimrman
- NTIS - New Technologies for the Information Society, Faculty of Applied Sciences, University of West Bohemia, Technická 8, Pilsen, Czech Republic
| | - Zbyněk Tonar
- NTIS - New Technologies for the Information Society, Faculty of Applied Sciences, University of West Bohemia, Technická 8, Pilsen, Czech Republic
| | - Jaroslav Špatenka
- Department of Cardiovascular Surgery, Motol University Hospital, Second Faculty of Medicine, Charles University in Prague, V Úvalu 84, 150 06, Prague, Czech Republic.,Department of Transplantations and Tissue Bank, Motol University Hospital, V Úvalu 84, 150 06, Prague, Czech Republic
| | - Ondřej Fabián
- Department of Pathology and Molecular Medicine, Motol University Hospital, Second Faculty of Medicine, Charles University in Prague, V Úvalu 84, 150 06, Prague, Czech Republic
| | - Jan Burkert
- Department of Cardiovascular Surgery, Motol University Hospital, Second Faculty of Medicine, Charles University in Prague, V Úvalu 84, 150 06, Prague, Czech Republic.,Department of Transplantations and Tissue Bank, Motol University Hospital, V Úvalu 84, 150 06, Prague, Czech Republic
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15
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Táborský M, Richter D, Tonar Z, Kubíková T, Herman A, Peregrin J, Husková Z, Kopkan L. Evaluation of later morphologic alterations in renal artery wall and renal nerves in response to catheter-based renal denervation in sheep: comparison of the single-point and multiple-point ablation catheters. Physiol Res 2018; 67:891-901. [PMID: 30204473 DOI: 10.33549/physiolres.933903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
This study evaluated the subacute morphologic alterations in renal artery wall and renal nerves in response to catheter-based renal denervation (RDN) in sheep and also compared the efficiency of single-point and multiple-point ablation catheters. Effect of each ablation catheter approved for the clinical use (Symplicity Flex(TM), Medtronic, Inc., or EnligHTN(TM), St. Jude Medical, INC.) was compared to intact contralateral renal artery in 12 sheep by histopathology and immunohistochemistry evaluation after a 10-day period post-RDN procedure. The safety was verified by extensive evaluation of kidney morphology. Vascular wall lesions and nerve injuries were more pronounced in those animals treated with multi-point EnligHTN catheter when compared with animals treated with single-point Symplicity Flex catheter. However, neither RDN procedure led to complete renal nerve ablation. Both systems, tested in the present study, provided only incomplete renal nerve ablation in sheep. Moreover, no appreciable progression of the nerve disintegration in subacute phase post-RDN procedure was observed. This study further supports the notion that the effectiveness remains fully dependent on anatomical inter-individual variability of the sympathetic nerve plexus accompanying the renal artery. Therefore, new systems providing deeper penetrance to targeted perivascular structure would be more efficient.
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Affiliation(s)
- M Táborský
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc, Czech Republic.
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16
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Alfonso-Garcia A, Haudenschild AK, Marcu L. Label-free assessment of carotid artery biochemical composition using fiber-based fluorescence lifetime imaging. BIOMEDICAL OPTICS EXPRESS 2018; 9:4064-4076. [PMID: 30615748 PMCID: PMC6157793 DOI: 10.1364/boe.9.004064] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 07/11/2018] [Accepted: 07/12/2018] [Indexed: 05/08/2023]
Abstract
Novel diagnostic tools with the ability to monitor variations in biochemical composition and provide benchmark indicators of vascular tissue maturation are needed to create functional tissue replacements. We investigated the ability of fiber-based, label-free multispectral fluorescent lifetime imaging (FLIm) to quantify the anatomical variations in biochemical composition of native carotid arteries and validated these results against biochemical assays. FLIm-derived parameters in spectral band 415-455 nm correlated with tissue collagen content (R2 = 0.64) and cell number (R2 = 0.61) and in spectral band 465-553 nm strongly correlated with elastin content (R2 = 0.89). These results suggest that FLIm holds great potential for assessing vascular tissue maturation and functional properties based on tissue autofluorescence.
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Affiliation(s)
- Alba Alfonso-Garcia
- Department of Biomedical Engineering, University of California, Davis, 451 E. Health Sciences Dr., Davis, CA 95616,
USA
- Authors contributed equally to this work
| | - Anne K. Haudenschild
- Department of Biomedical Engineering, University of California, Davis, 451 E. Health Sciences Dr., Davis, CA 95616,
USA
- Authors contributed equally to this work
| | - Laura Marcu
- Department of Biomedical Engineering, University of California, Davis, 451 E. Health Sciences Dr., Davis, CA 95616,
USA
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17
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Kubíková T, Kochová P, Brázdil J, Špatenka J, Burkert J, Králíčková M, Tonar Z. The composition and biomechanical properties of human cryopreserved aortas, pulmonary trunks, and aortic and pulmonary cusps. Ann Anat 2017; 212:17-26. [DOI: 10.1016/j.aanat.2017.03.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 01/06/2017] [Accepted: 03/21/2017] [Indexed: 11/26/2022]
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18
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Noninvasive Measurement of Ear Cartilage Elasticity on the Cellular Level: A New Method to Provide Biomechanical Information for Tissue Engineering. PLASTIC AND RECONSTRUCTIVE SURGERY-GLOBAL OPEN 2017; 5:e1147. [PMID: 28280656 PMCID: PMC5340471 DOI: 10.1097/gox.0000000000001147] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 10/07/2016] [Indexed: 11/26/2022]
Abstract
Background: An important feature of auricular cartilage is its stiffness. To tissue engineer new cartilage, we need objective tools to provide us with the essential biomechanical information to mimic optimal conditions for chondrogenesis and extracellular matrix (ECM) development. In this study, we used an optomechanical sensor to investigate the elasticity of auricular cartilage ECM and tested whether sensitivity and measurement reproducibility of the sensor would be sufficient to accurately detect (subtle) differences in matrix compositions in healthy, diseased, or regenerated cartilage. Methods: As a surrogate model to different cartilage ECM compositions, goat ears (n = 9) were subjected to different degradation processes to remove the matrix components elastin and glycosaminoglycans. Individual ear samples were cut and divided into 3 groups. Group 1 served as control and was measured within 2 hours after animal death and at 24 and 48 hours, and groups 2 and 3 were measured after 24- and 48-h hyaluronidase or elastase digestion. Per sample, 9 consecutive measurements were taken ±300 μm apart. Results: Good reproducibility was seen between consecutive measurements with an overall interclass correlation coefficient average of 0.9 (0.81–0.98). Although degradation led to variable results, overall, a significant difference was seen between treatment groups after 48 hours (control, 4.2 MPa [±0.5] vs hyaluronidase, 2.0 MPa [±0.3], and elastase, 3.0 MPa [±0.4]; both P < 0.001). Conclusions: The optomechanical sensor system we used provided a fast and reliable method to perform measurements of cartilage ECM in a reverse tissue-engineering model. In future applications, this method seems feasible for the monitoring of changes in stiffness during the development of tissue-engineered auricular cartilage.
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19
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Pu L, Wu J, Pan X, Hou Z, Zhang J, Chen W, Na Z, Meng M, Ni H, Wang L, Li Y, Jiang L. Determining the optimal protocol for preparing an acellular scaffold of tissue engineered small-diameter blood vessels. J Biomed Mater Res B Appl Biomater 2017; 106:619-631. [PMID: 28271637 DOI: 10.1002/jbm.b.33827] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 10/13/2016] [Accepted: 11/22/2016] [Indexed: 12/18/2022]
Abstract
Although detergent-based decellularization protocols have been widely used to obtain a natural extracellular matrix (ECM) scaffold in tissue engineering, some key challenges still exist. To achieve an optimum natural decellularized scaffold for the construction of tissue-engineered small-diameter blood vessels (TEBV), porcine carotid arteries (PCAs) were decellularized by combining sodium dodecyl sulfate (SDS), sodium deoxycholate (SDC) and Triton X-100 (Triton) in different concentrations. Tissue samples were processed and their histological, biochemical and biomechanical characteristics were investigated. Results showed that only two methods 0.5% (SDS + SDC) and 1% (SDS + SDC) could completely remove of the cellular contents and preserve the native ECM architecture. Furthermore, 1% (SDS + SDC) based methods acquire preferable porosity and suitable mechanical strength. Residual Triton in the ECM scaffold holds intensive cytotoxity. In conclusion, 1%(SDS + SDC) based method can obtain a superior PCAs scaffold for the construction of TEBV. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 619-631, 2018.
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Affiliation(s)
- Lei Pu
- Cardiovascular Surgery, Yan'an Affiliated Hospital of Kunming Medical University, Kunming Medical University, Kunming, Yunnan, People's Republic of China
| | - Jian Wu
- Cardiovascular Surgery, Yan'an Affiliated Hospital of Kunming Medical University, Kunming Medical University, Kunming, Yunnan, People's Republic of China.,Cardiovascular Surgery, Institution of Yunnan, Kunming, Yunnan, People's Republic of China
| | - Xingna Pan
- Cardiovascular Surgery, Yan'an Affiliated Hospital of Kunming Medical University, Kunming Medical University, Kunming, Yunnan, People's Republic of China
| | - Zongliu Hou
- Central Laboratory, Yan'an Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People's Republic of China
| | - Jing Zhang
- Department of Anesthesiology, Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People's Republic of China
| | - Wenmin Chen
- Cardiovascular Surgery, Yan'an Affiliated Hospital of Kunming Medical University, Kunming Medical University, Kunming, Yunnan, People's Republic of China.,Cardiovascular Surgery, Institution of Yunnan, Kunming, Yunnan, People's Republic of China
| | - Zhuhui Na
- Cardiovascular Surgery, Yan'an Affiliated Hospital of Kunming Medical University, Kunming Medical University, Kunming, Yunnan, People's Republic of China.,Cardiovascular Surgery, Institution of Yunnan, Kunming, Yunnan, People's Republic of China
| | - Mingyao Meng
- Central Laboratory, Yan'an Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People's Republic of China
| | - Haiyan Ni
- Department of Pathology, Yan'an Affiliated Hospital of Kunming Medical University, Kunming Medical University, Kunming, Yunnan, People's Republic of China
| | - Liqiong Wang
- Department of Pathology, Yan'an Affiliated Hospital of Kunming Medical University, Kunming Medical University, Kunming, Yunnan, People's Republic of China
| | - Yaxiong Li
- Cardiovascular Surgery, Yan'an Affiliated Hospital of Kunming Medical University, Kunming Medical University, Kunming, Yunnan, People's Republic of China.,Cardiovascular Surgery, Institution of Yunnan, Kunming, Yunnan, People's Republic of China
| | - Lihong Jiang
- Cardiovascular Surgery, Yan'an Affiliated Hospital of Kunming Medical University, Kunming Medical University, Kunming, Yunnan, People's Republic of China.,Cardiovascular Surgery, Institution of Yunnan, Kunming, Yunnan, People's Republic of China
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20
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Controlled peel testing of a model tissue for diseased aorta. J Biomech 2016; 49:3667-3675. [DOI: 10.1016/j.jbiomech.2016.09.040] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 09/19/2016] [Accepted: 09/30/2016] [Indexed: 11/22/2022]
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21
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Chen H, Kassab GS. Microstructure-based biomechanics of coronary arteries in health and disease. J Biomech 2016; 49:2548-59. [PMID: 27086118 PMCID: PMC5028318 DOI: 10.1016/j.jbiomech.2016.03.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 03/16/2016] [Indexed: 12/27/2022]
Abstract
Coronary atherosclerosis is the major cause of mortality and disability in developed nations. A deeper understanding of mechanical properties of coronary arteries and hence their mechanical response to stress is significant for clinical prevention and treatment. Microstructure-based models of blood vessels can provide predictions of arterial mechanical response at the macro- and micro-mechanical level for each constituent structure. Such models must be based on quantitative data of structural parameters (constituent content, orientation angle and dimension) and mechanical properties of individual adventitia and media layers of normal arteries as well as change of structural and mechanical properties of atherosclerotic arteries. The microstructural constitutive models of healthy coronary arteries consist of three major mechanical components: collagen, elastin, and smooth muscle cells, while the models of atherosclerotic arteries should account for additional constituents including intima, fibrous plaque, lipid, calcification, etc. This review surveys the literature on morphology, mechanical properties, and microstructural constitutive models of normal and atherosclerotic coronary arteries. It also provides an overview of current gaps in knowledge that must be filed in order to advance this important area of research for understanding initiation, progression and clinical treatment of vascular disease. Patient-specific structural models are highlighted to provide diagnosis, virtual planning of therapy and prognosis when realistic patient-specific geometries and material properties of diseased vessels can be acquired by advanced imaging techniques.
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Affiliation(s)
- Huan Chen
- California Medical Innovations Institute, Inc., San Diego, CA 92121, United States
| | - Ghassan S Kassab
- California Medical Innovations Institute, Inc., San Diego, CA 92121, United States.
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22
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Noble C, Smulders N, Green NH, Lewis R, Carré MJ, Franklin SE, MacNeil S, Taylor ZA. Creating a model of diseased artery damage and failure from healthy porcine aorta. J Mech Behav Biomed Mater 2016; 60:378-393. [DOI: 10.1016/j.jmbbm.2016.02.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 02/05/2016] [Accepted: 02/10/2016] [Indexed: 01/24/2023]
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23
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Chen H, Guo X, Luo T, Kassab GS. A validated 3D microstructure-based constitutive model of coronary artery adventitia. J Appl Physiol (1985) 2016; 121:333-42. [PMID: 27174925 PMCID: PMC4967241 DOI: 10.1152/japplphysiol.00937.2015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 05/05/2016] [Indexed: 11/22/2022] Open
Abstract
A structure-based model that accurately predicts micro- or macromechanical behavior of blood vessels is necessary to understand vascular physiology. Based on recently measured microstructural data, we propose a three-dimensional microstructural model of coronary adventitia that incorporates the elastin and collagen distributions throughout the wall. The role of ground substance was found to be negligible under physiological axial stretch λz = 1.3, based on enzyme degradation of glycosaminoglycans in swine coronary adventitia (n = 5). The thick collagen bundles of outer adventitia (n = 4) were found to be undulated and unengaged at physiological loads, whereas the inner adventitia consisted of multiple sublayers of entangled fibers that bear the majority of load at higher pressures. The microstructural model was validated against biaxial (inflation and extension) experiments of coronary adventitia (n = 5). The model accurately predicted the nonlinear responses of the adventitia, even at high axial force (axial stretch ratio λz = 1.5). The model also enabled a reliable estimation of material parameters of individual fibers that were physically reasonable. A sensitivity analysis was performed to assess the effect of using mean values of the distributions for fiber orientation and waviness as opposed to the full distributions. The simplified mean analysis affects the fiber stress-strain relation, resulting in incorrect estimation of mechanical parameters, which underscores the need for measurements of fiber distribution for a rigorous analysis of fiber mechanics. The validated structure-based model of coronary adventitia provides a deeper understanding of vascular mechanics in health and can be extended to disease conditions.
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Affiliation(s)
- Huan Chen
- California Medical Innovations Institute, Incorporated, San Diego, California
| | - Xiaomei Guo
- California Medical Innovations Institute, Incorporated, San Diego, California
| | - Tong Luo
- California Medical Innovations Institute, Incorporated, San Diego, California
| | - Ghassan S Kassab
- California Medical Innovations Institute, Incorporated, San Diego, California
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Abstract
Vascular smooth muscle (VSM; see Table 1 for a list of abbreviations) is a heterogeneous biomaterial comprised of cells and extracellular matrix. By surrounding tubes of endothelial cells, VSM forms a regulated network, the vasculature, through which oxygenated blood supplies specialized organs, permitting the development of large multicellular organisms. VSM cells, the engine of the vasculature, house a set of regulated nanomotors that permit rapid stress-development, sustained stress-maintenance and vessel constriction. Viscoelastic materials within, surrounding and attached to VSM cells, comprised largely of polymeric proteins with complex mechanical characteristics, assist the engine with countering loads imposed by the heart pump, and with control of relengthening after constriction. The complexity of this smart material can be reduced by classical mechanical studies combined with circuit modeling using spring and dashpot elements. Evaluation of the mechanical characteristics of VSM requires a more complete understanding of the mechanics and regulation of its biochemical parts, and ultimately, an understanding of how these parts work together to form the machinery of the vascular tree. Current molecular studies provide detailed mechanical data about single polymeric molecules, revealing viscoelasticity and plasticity at the protein domain level, the unique biological slip-catch bond, and a regulated two-step actomyosin power stroke. At the tissue level, new insight into acutely dynamic stress-strain behavior reveals smooth muscle to exhibit adaptive plasticity. At its core, physiology aims to describe the complex interactions of molecular systems, clarifying structure-function relationships and regulation of biological machines. The intent of this review is to provide a comprehensive presentation of one biomachine, VSM.
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Affiliation(s)
- Paul H Ratz
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, Virginia, USA
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25
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Morphometric and biomechanical remodeling of the small intestine during aging in rats. J Biomech 2015; 48:4271-8. [DOI: 10.1016/j.jbiomech.2015.10.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 10/22/2015] [Accepted: 10/23/2015] [Indexed: 01/27/2023]
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Zhao J, Gregersen H. Esophageal morphometric and biomechanical changes during aging in rats. Neurogastroenterol Motil 2015; 27:1638-47. [PMID: 26303784 DOI: 10.1111/nmo.12661] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 07/30/2015] [Indexed: 02/08/2023]
Abstract
BACKGROUND Human studies have demonstrated aging-related changes in esophagus which may contribute to the increased rate of gastro-esophageal reflux in elderly. The aim of this study was to investigate esophageal morphometric and biomechanical remodeling in aging rats to obtain detailed information about aging-related changes. METHODS Twenty-four male Wistar rats, aged from 6 to 22 months, were studied. Morphometric data were obtained by measuring the wall thickness and cross-sectional area. The esophageal diameter and length were obtained from digitized images of the segments at preselected luminal pressure levels and at no-load and zero-stress states. Circumferential and longitudinal stresses (force per area) and strains (deformation) were computed from the length, diameter and pressure data, and from the zero-stress state geometry. KEY RESULTS The esophageal parameters such as the weight per unit length, the wall thickness and the wall cross-sectional area increased slightly from 6 to 22 months (p < 0.05 to p < 0.001). The opening angle gradually decreased during aging (p < 0.05). The interface between the mucosa-submucosa and muscle layers slightly moved outwards and the neutral axis moved inwards during aging. The stress-strain data showed that the esophageal wall became stiffer circumferentially and longitudinally during aging (p < 0.05, p < 0.01). However, the circumferential wall stiffness showed no further change after 12 months. CONCLUSIONS & INFERENCES A pronounced morphometric and biomechanical remodeling occurred in the rat esophagus during aging.
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Affiliation(s)
- J Zhao
- Giome Academia, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,GIOME and the Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, China
| | - H Gregersen
- GIOME and the Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, China
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Tonar Z, Kubíková T, Prior C, Demjén E, Liška V, Králíčková M, Witter K. Segmental and age differences in the elastin network, collagen, and smooth muscle phenotype in the tunica media of the porcine aorta. Ann Anat 2015; 201:79-90. [DOI: 10.1016/j.aanat.2015.05.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 05/26/2015] [Accepted: 05/26/2015] [Indexed: 12/18/2022]
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Tonar Z, Kochova P, Cimrman R, Perktold J, Witter K. Segmental differences in the orientation of smooth muscle cells in the tunica media of porcine aortae. Biomech Model Mechanobiol 2014; 14:315-32. [DOI: 10.1007/s10237-014-0605-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 07/01/2014] [Indexed: 01/29/2023]
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Dinardo CL, Venturini G, Zhou EH, Watanabe IS, Campos LCG, Dariolli R, da Motta-Leal-Filho JM, Carvalho VM, Cardozo KHM, Krieger JE, Alencar AM, Pereira AC. Variation of mechanical properties and quantitative proteomics of VSMC along the arterial tree. Am J Physiol Heart Circ Physiol 2014; 306:H505-16. [DOI: 10.1152/ajpheart.00655.2013] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vascular smooth muscle cells (VSMCs) are thought to assume a quiescent and homogeneous mechanical behavior after arterial tree development phase. However, VSMCs are known to be molecularly heterogeneous in other aspects and their mechanics may play a role in pathological situations. Our aim was to evaluate VSMCs from different arterial beds in terms of mechanics and proteomics, as well as investigate factors that may influence this phenotype. VSMCs obtained from seven arteries were studied using optical magnetic twisting cytometry (both in static state and after stretching) and shotgun proteomics. VSMC mechanical data were correlated with anatomical parameters and ultrastructural images of their vessels of origin. Femoral, renal, abdominal aorta, carotid, mammary, and thoracic aorta exhibited descending order of stiffness (G, P < 0.001). VSMC mechanical data correlated with the vessel percentage of elastin and amount of surrounding extracellular matrix (ECM), which decreased with the distance from the heart. After 48 h of stretching simulating regional blood flow of elastic arteries, VSMCs exhibited a reduction in basal rigidity. VSMCs from the thoracic aorta expressed a significantly higher amount of proteins related to cytoskeleton structure and organization vs. VSMCs from the femoral artery. VSMCs are heterogeneous in terms of mechanical properties and expression/organization of cytoskeleton proteins along the arterial tree. The mechanical phenotype correlates with the composition of ECM and can be modulated by cyclic stretching imposed on VSMCs by blood flow circumferential stress.
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Affiliation(s)
- Carla Luana Dinardo
- Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil
| | - Gabriela Venturini
- Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil
| | - Enhua H. Zhou
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts
| | - Ii Sei Watanabe
- Institute of Biomedical Sciences, Department of Anatomy, University of São Paulo, São Paulo, Brazil
| | | | - Rafael Dariolli
- Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil
| | | | | | | | - José Eduardo Krieger
- Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil
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Salum E, Butlin M, Kals J, Zilmer M, Eha J, Avolio AP, Arend A, Aunapuu M, Kampus P. Angiotensin II receptor blocker telmisartan attenuates aortic stiffening and remodelling in STZ-diabetic rats. Diabetol Metab Syndr 2014; 6:57. [PMID: 24920962 PMCID: PMC4035834 DOI: 10.1186/1758-5996-6-57] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 05/06/2014] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Prevention or attenuation of diabetic vascular complications includes anti-hypertensive treatment with renin-angiotensin system inhibitors on account of their protective effects beyond blood pressure reduction. The present study aimed to investigate the effects of telmisartan, an angiotensin II type 1 receptor blocker (ARB), on blood pressure, aortic stiffening, and aortic remodelling in experimental type 1 diabetes in rats. METHODS Diabetes was induced by streptozotocin (STZ) (65 mg/kg) in male Wistar rats. One diabetic group was treated for 10 weeks with telmisartan (10 mg/kg/day p/o). Pressure-independent aortic pulse wave velocity (PWV) was measured under anaesthesia after intravenous infusion of phenylephrine and nitroglycerine. Aortic wall samples were collected for histomorphometrical analysis. RESULTS Untreated diabetes imposed differential effects on aortic stiffening, as demonstrated by increased isobaric PWV over a range of high blood pressures, but not at lower blood pressures. This was associated with loss and disruption of elastin fibres and an increase in collagen fibres in the aortic media. Treatment with telmisartan decreased resting blood pressure, reduced aortic stiffness, and partially prevented the degradation of elastin network within the aortic wall. CONCLUSIONS Telmisartan improved the structural and functional indices of aortic stiffening induced by untreated STZ-diabetes, demonstrating the importance of ARBs in the therapeutic approach to diabetic vascular complications.
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Affiliation(s)
- Erik Salum
- Department of Cardiology, University of Tartu, 8 Puusepa Street, Tartu 51014, Estonia
- Endothelial Centre, University of Tartu, 8 Puusepa Street, Tartu 51014, Estonia
- Department of Biochemistry, Centre of Excellence for Translational Medicine, University of Tartu, 19 Ravila Street, Tartu 50411, Estonia
| | - Mark Butlin
- The Australian School of Advanced Medicine, 2 Technology Place, Macquarie University, Sydney, NSW 2109, Australia
| | - Jaak Kals
- Endothelial Centre, University of Tartu, 8 Puusepa Street, Tartu 51014, Estonia
- Department of Biochemistry, Centre of Excellence for Translational Medicine, University of Tartu, 19 Ravila Street, Tartu 50411, Estonia
- Department of Vascular Surgery, Tartu University Hospital, 8 Puusepa Street, Tartu 51014, Estonia
| | - Mihkel Zilmer
- Endothelial Centre, University of Tartu, 8 Puusepa Street, Tartu 51014, Estonia
- Department of Biochemistry, Centre of Excellence for Translational Medicine, University of Tartu, 19 Ravila Street, Tartu 50411, Estonia
| | - Jaan Eha
- Department of Cardiology, University of Tartu, 8 Puusepa Street, Tartu 51014, Estonia
- Endothelial Centre, University of Tartu, 8 Puusepa Street, Tartu 51014, Estonia
| | - Alberto P Avolio
- The Australian School of Advanced Medicine, 2 Technology Place, Macquarie University, Sydney, NSW 2109, Australia
| | - Andres Arend
- Department of Anatomy, University of Tartu, 19 Ravila Street, Tartu 50411, Estonia
| | - Marina Aunapuu
- Department of Anatomy, University of Tartu, 19 Ravila Street, Tartu 50411, Estonia
- Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, 62 Fr. Kreutzwaldi Street, Tartu 51014, Estonia
| | - Priit Kampus
- Department of Cardiology, University of Tartu, 8 Puusepa Street, Tartu 51014, Estonia
- Endothelial Centre, University of Tartu, 8 Puusepa Street, Tartu 51014, Estonia
- Department of Biochemistry, Centre of Excellence for Translational Medicine, University of Tartu, 19 Ravila Street, Tartu 50411, Estonia
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Chen H, Luo T, Zhao X, Lu X, Huo Y, Kassab GS. Microstructural constitutive model of active coronary media. Biomaterials 2013; 34:7575-83. [PMID: 23859656 DOI: 10.1016/j.biomaterials.2013.06.035] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 06/21/2013] [Indexed: 11/15/2022]
Abstract
Although vascular smooth muscle cells (VSMCs) are pivotal in physiology and pathology, there is a lack of detailed morphological data on these cells. The objective of this study was to determine dimensions (width and length) and orientation of swine coronary VSMCs and to develop a microstructural constitutive model of active media. The dimensions, spatial aspect ratio and orientation angle of VSMCs measured at zero-stress state were found to follow continuous normal (or bimodal normal) distributions. The VSMCs aligned off circumferential direction of blood vessels with symmetrical polar angles 18.7° ± 10.9°, and the local VSMC deformation was affine with tissue-level deformation. A microstructure-based active constitutive model was developed to predict the biaxial vasoactivity of coronary media, based on experimental measurements of geometrical and deformation features of VSMCs. The results revealed that the axial active response of blood vessels is associated with multi-axial contraction as well as oblique VSMC arrangement. The present morphological database is essential for developing accurate structural models and is seminal for understanding the biomechanics of muscular vessels.
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Affiliation(s)
- Huan Chen
- Department of Biomedical Engineering, Indiana University Purdue University Indianapolis, Indianapolis, IN 46202, United States
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