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Liu N, Jiang J, Liu T, Chen H, Jiang N. Compositional, Structural, and Biomechanical Properties of Three Different Soft Tissue-Hard Tissue Insertions: A Comparative Review. ACS Biomater Sci Eng 2024; 10:2659-2679. [PMID: 38697939 DOI: 10.1021/acsbiomaterials.3c01796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
Connective tissue attaches to bone across an insertion with spatial gradients in components, microstructure, and biomechanics. Due to regional stress concentrations between two mechanically dissimilar materials, the insertion is vulnerable to mechanical damage during joint movements and difficult to repair completely, which remains a significant clinical challenge. Despite interface stress concentrations, the native insertion physiologically functions as the effective load-transfer device between soft tissue and bone. This review summarizes tendon, ligament, and meniscus insertions cross-sectionally, which is novel in this field. Herein, the similarities and differences between the three kinds of insertions in terms of components, microstructure, and biomechanics are compared in great detail. This review begins with describing the basic components existing in the four zones (original soft tissue, uncalcified fibrocartilage, calcified fibrocartilage, and bone) of each kind of insertion, respectively. It then discusses the microstructure constructed from collagen, glycosaminoglycans (GAGs), minerals and others, which provides key support for the biomechanical properties and affects its physiological functions. Finally, the review continues by describing variations in mechanical properties at the millimeter, micrometer, and nanometer scale, which minimize stress concentrations and control stretch at the insertion. In summary, investigating the contrasts between the three has enlightening significance for future directions of repair strategies of insertion diseases and for bioinspired approaches to effective soft-hard interfaces and other tough and robust materials in medicine and engineering.
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Affiliation(s)
- Nian Liu
- West China School of Stomatology, Sichuan University, Chengdu, Sichuan 610207, China
| | - Jialing Jiang
- West China School of Stomatology, Sichuan University, Chengdu, Sichuan 610207, China
| | - Tiancheng Liu
- West China Hospital, Sichuan University, Chengdu, Sichuan 610207, China
| | - Haozhe Chen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, China
| | - Nan Jiang
- State Key Laboratory of Oral Diseases, & National Clinical Research Center for Oral Disease, & West China Hospital of Stomatology and the Research Center for Nano Biomaterials, Analytical & Testing Center, Sichuan University, Chengdu, Sichuan 610041, China
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Rabia B, Thanigaimani S, Golledge J. The potential involvement of glycocalyx disruption in abdominal aortic aneurysm pathogenesis. Cardiovasc Pathol 2024; 70:107629. [PMID: 38461960 DOI: 10.1016/j.carpath.2024.107629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 03/03/2024] [Accepted: 03/04/2024] [Indexed: 03/12/2024] Open
Abstract
BACKGROUND Abdominal aortic aneurysm is a weakening and expansion of the abdominal aorta. Currently, there is no drug treatment to limit abdominal aortic aneurysm growth. The glycocalyx is the outermost layer of the cell surface, mainly composed of glycosaminoglycans and proteoglycans. OBJECTIVE The aim of this review was to identify a potential relationship between glycocalyx disruption and abdominal aortic aneurysm pathogenesis. METHODS A narrative review of relevant published research was conducted. RESULTS Glycocalyx disruption has been reported to enhance vascular permeability, impair immune responses, dysregulate endothelial function, promote extracellular matrix remodeling and modulate mechanotransduction. All these effects are implicated in abdominal aortic aneurysm pathogenesis. Glycocalyx disruption promotes inflammation through exposure of adhesion molecules and release of proinflammatory mediators. Glycocalyx disruption affects how the endothelium responds to shear stress by reducing nitric oxide availabilty and adversely affecting the storage and release of several antioxidants, growth factors, and antithromotic proteins. These changes exacerbate oxidative stress, stimulate vascular smooth muscle cell dysfunction, and promote thrombosis, all effects implicated in abdominal aortic aneurysm pathogenesis. Deficiency of key component of the glycocalyx, such as syndecan-4, were reported to promote aneurysm formation and rupture in the angiotensin-II and calcium chloride induced mouse models of abdominal aortic aneurysm. CONCLUSION This review provides a summary of past research which suggests that glycocalyx disruption may play a role in abdominal aortic aneurysm pathogenesis. Further research is needed to establish a causal link between glycocalyx disruption and abdominal aortic aneurysm development.
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Affiliation(s)
- Bibi Rabia
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, Queensland 4811, Australia; Department of Pharmacy, Hazara University, Mansehra 21300, Pakistan
| | - Shivshankar Thanigaimani
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, Queensland 4811, Australia; The Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, Queensland 4811, Australia
| | - Jonathan Golledge
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, Queensland 4811, Australia; The Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, Queensland 4811, Australia; The Department of Vascular and Endovascular Surgery, The Townsville University Hospital, Townsville, Queensland 4810, Australia.
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Chato-Astrain J, Roda O, Carriel V, Hita-Contreras F, Sánchez-Montesinos I, Alaminos M, Hernández-Cortés P. Histological characterization of the human scapholunate ligament. Microsc Res Tech 2024; 87:257-271. [PMID: 37767790 DOI: 10.1002/jemt.24428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 09/12/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023]
Abstract
The scapholunate interosseous ligament (SLIL) plays a fundamental role in stabilizing the wrist bones, and its disruption is a frequent cause of wrist arthrosis and disfunction. Traditionally, this structure is considered to be a variety of fibrocartilaginous tissue and consists of three regions: dorsal, membranous and palmar. Despite its functional relevance, the exact composition of the human SLIL is not well understood. In the present work, we have analyzed the human SLIL and control tissues from the human hand using an array of histological, histochemical and immunohistochemical methods to characterize each region of this structure. Results reveal that the SLIL is heterogeneous, and each region can be subdivided in two zones that are histologically different to the other zones. Analysis of collagen and elastic fibers, and several proteoglycans, glycoproteins and glycosaminoglycans confirmed that the different regions can be subdivided in two zones that have their own structure and composition. In general, all parts of the SLIL resemble the histological structure of the control articular cartilage, especially the first part of the membranous region (zone M1). Cells showing a chondrocyte-like phenotype as determined by S100 were more abundant in M1, whereas the zone containing more CD73-positive stem cells was D2. These results confirm the heterogeneity of the human SLIL and could contribute to explain why certain zones of this structure are more prone to structural damage and why other zones have specific regeneration potential. RESEARCH HIGHLIGHTS: Application of an array of histological analysis methods allowed us to demonstrate that the human scapholunate ligament is heterogeneous and consists of at least six different regions sharing similarities with the human cartilage, ligament and other anatomical structures.
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Affiliation(s)
- Jesús Chato-Astrain
- Tissue Engineering Group, Department of Histology, Faculty of Medicine, University of Granada, Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, Granada, Spain
| | - Olga Roda
- Department of Human Anatomy and Embryology, Faculty of Medicine, University of Granada, Granada, Spain
| | - Víctor Carriel
- Tissue Engineering Group, Department of Histology, Faculty of Medicine, University of Granada, Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, Granada, Spain
| | - Fidel Hita-Contreras
- Department of Health Sciences, Faculty of Health Sciences, University of Jaén, Jaén, Spain
| | - Indalecio Sánchez-Montesinos
- Instituto de Investigación Biosanitaria ibs.GRANADA, Granada, Spain
- Department of Human Anatomy and Embryology, Faculty of Medicine, University of Granada, Granada, Spain
| | - Miguel Alaminos
- Tissue Engineering Group, Department of Histology, Faculty of Medicine, University of Granada, Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, Granada, Spain
| | - Pedro Hernández-Cortés
- Instituto de Investigación Biosanitaria ibs.GRANADA, Granada, Spain
- Department of Surgery and Surgical Specialties, Faculty of Medicine, University of Granada, Granada, Spain
- Division of Traumatology and Orthopedic Surgery, San Cecilio University Hospital, Granada, Spain
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Wang Y, Panicker IS, Anesi J, Sargisson O, Atchison B, Habenicht AJR. Animal Models, Pathogenesis, and Potential Treatment of Thoracic Aortic Aneurysm. Int J Mol Sci 2024; 25:901. [PMID: 38255976 PMCID: PMC10815651 DOI: 10.3390/ijms25020901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 01/03/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
Thoracic aortic aneurysm (TAA) has a prevalence of 0.16-0.34% and an incidence of 7.6 per 100,000 person-years, accounting for 1-2% of all deaths in Western countries. Currently, no effective pharmacological therapies have been identified to slow TAA development and prevent TAA rupture. Large TAAs are treated with open surgical repair and less invasive thoracic endovascular aortic repair, both of which have high perioperative mortality risk. Therefore, there is an urgent medical need to identify the cellular and molecular mechanisms underlying TAA development and rupture to develop new therapies. In this review, we summarize animal TAA models including recent developments in porcine and zebrafish models: porcine models can assess new therapeutic devices or intervention strategies in a large mammal and zebrafish models can employ large-scale small-molecule suppressor screening in microwells. The second part of the review covers current views of TAA pathogenesis, derived from recent studies using these animal models, with a focus on the roles of the transforming growth factor-beta (TGFβ) pathway and the vascular smooth muscle cell (VSMC)-elastin-contractile unit. The last part discusses TAA treatment options as they emerge from recent preclinical studies.
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Affiliation(s)
- Yutang Wang
- Discipline of Life Science, Institute of Innovation, Science and Sustainability, Federation University Australia, Ballarat, VIC 3353, Australia; (I.S.P.)
| | - Indu S. Panicker
- Discipline of Life Science, Institute of Innovation, Science and Sustainability, Federation University Australia, Ballarat, VIC 3353, Australia; (I.S.P.)
| | - Jack Anesi
- Discipline of Life Science, Institute of Innovation, Science and Sustainability, Federation University Australia, Ballarat, VIC 3353, Australia; (I.S.P.)
| | - Owen Sargisson
- Discipline of Life Science, Institute of Innovation, Science and Sustainability, Federation University Australia, Ballarat, VIC 3353, Australia; (I.S.P.)
| | - Benjamin Atchison
- Discipline of Life Science, Institute of Innovation, Science and Sustainability, Federation University Australia, Ballarat, VIC 3353, Australia; (I.S.P.)
| | - Andreas J. R. Habenicht
- Institute for Cardiovascular Prevention, Ludwig-Maximilians-Universität München (LMU), 80336 Munich, Germany;
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Wang M, Ching-Johnson JA, Yin H, O’Neil C, Li AX, Chu MWA, Bartha R, Pickering JG. Mapping microarchitectural degeneration in the dilated ascending aorta with ex vivo diffusion tensor imaging. EUROPEAN HEART JOURNAL OPEN 2024; 4:oead128. [PMID: 38162403 PMCID: PMC10755346 DOI: 10.1093/ehjopen/oead128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 10/26/2023] [Accepted: 11/30/2023] [Indexed: 01/03/2024]
Abstract
Aims Thoracic aortic aneurysms (TAAs) carry a risk of catastrophic dissection. Current strategies to evaluate this risk entail measuring aortic diameter but do not image medial degeneration, the cause of TAAs. We sought to determine if the advanced magnetic resonance imaging (MRI) acquisition strategy, diffusion tensor imaging (DTI), could delineate medial degeneration in the ascending thoracic aorta. Methods and results Porcine ascending aortas were subjected to enzyme microinjection, which yielded local aortic medial degeneration. These lesions were detected by DTI, using a 9.4 T MRI scanner, based on tensor disorientation, disrupted diffusion tracts, and altered DTI metrics. High-resolution spatial analysis revealed that fractional anisotropy positively correlated, and mean and radial diffusivity inversely correlated, with smooth muscle cell (SMC) and elastin content (P < 0.001 for all). Ten operatively harvested human ascending aorta samples (mean subject age 61.6 ± 13.3 years, diameter range 29-64 mm) showed medial pathology that was more diffuse and more complex. Nonetheless, DTI metrics within an aorta spatially correlated with SMC, elastin, and, especially, glycosaminoglycan (GAG) content. Moreover, there were inter-individual differences in slice-averaged DTI metrics. Glycosaminoglycan accumulation and elastin degradation were captured by reduced fractional anisotropy (R2 = 0.47, P = 0.043; R2 = 0.76, P = 0.002), with GAG accumulation also captured by increased mean diffusivity (R2 = 0.46, P = 0.045) and increased radial diffusivity (R2 = 0.60, P = 0.015). Conclusion Ex vivo high-field DTI can detect ascending aorta medial degeneration and can differentiate TAAs in accordance with their histopathology, especially elastin and GAG changes. This non-destructive window into aortic medial microstructure raises prospects for probing the risks of TAAs beyond lumen dimensions.
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Affiliation(s)
- Mofei Wang
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N. London, Canada, N6A 5B7
- Department of Biochemistry, Western University, 1151 Richmond St. N. London, Canada, N6A 3K7
| | - Justin A Ching-Johnson
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N. London, Canada, N6A 5B7
- Department of Medical Biophysics, Western University, 1151 Richmond St. N. London, Canada, N6A 3K7
| | - Hao Yin
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N. London, Canada, N6A 5B7
| | - Caroline O’Neil
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N. London, Canada, N6A 5B7
| | - Alex X Li
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N. London, Canada, N6A 5B7
| | - Michael W A Chu
- Department of Surgery, Western University, 1151 Richmond St. N. London, Canada, N6A 3K7
- London Health Sciences Centre, 339 Windermere Rd, London, Ontario, Canada, N6A 5A5
| | - Robert Bartha
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N. London, Canada, N6A 5B7
- Department of Medical Biophysics, Western University, 1151 Richmond St. N. London, Canada, N6A 3K7
| | - J Geoffrey Pickering
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N. London, Canada, N6A 5B7
- Department of Biochemistry, Western University, 1151 Richmond St. N. London, Canada, N6A 3K7
- Department of Medical Biophysics, Western University, 1151 Richmond St. N. London, Canada, N6A 3K7
- London Health Sciences Centre, 339 Windermere Rd, London, Ontario, Canada, N6A 5A5
- Department of Medicine, Western University, 1151 Richmond St. N. London, Canada N6A 3K7
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Wang Q, Chi L. The Alterations and Roles of Glycosaminoglycans in Human Diseases. Polymers (Basel) 2022; 14:polym14225014. [PMID: 36433141 PMCID: PMC9694910 DOI: 10.3390/polym14225014] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/14/2022] [Accepted: 11/15/2022] [Indexed: 11/22/2022] Open
Abstract
Glycosaminoglycans (GAGs) are a heterogeneous family of linear polysaccharides which are composed of a repeating disaccharide unit. They are also linked to core proteins to form proteoglycans (PGs). GAGs/PGs are major components of the cell surface and the extracellular matrix (ECM), and they display critical roles in development, normal function, and damage response in the body. Some properties (such as expression quantity, molecular weight, and sulfation pattern) of GAGs may be altered under pathological conditions. Due to the close connection between these properties and the function of GAGs/PGs, the alterations are often associated with enormous changes in the physiological/pathological status of cells and organs. Therefore, these GAGs/PGs may serve as marker molecules of disease. This review aimed to investigate the structural alterations and roles of GAGs/PGs in a range of diseases, such as atherosclerosis, cancer, diabetes, neurodegenerative disease, and virus infection. It is hoped to provide a reference for disease diagnosis, monitoring, prognosis, and drug development.
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Pierce GL, Coutinho TA, DuBose LE, Donato AJ. Is It Good to Have a Stiff Aorta with Aging? Causes and Consequences. Physiology (Bethesda) 2022; 37:154-173. [PMID: 34779281 PMCID: PMC8977146 DOI: 10.1152/physiol.00035.2021] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 10/28/2021] [Accepted: 11/08/2021] [Indexed: 01/09/2023] Open
Abstract
Aortic stiffness increases with advancing age, more than doubling during the human life span, and is a robust predictor of cardiovascular disease (CVD) clinical events independent of traditional risk factors. The aorta increases in diameter and length to accommodate growing body size and cardiac output in youth, but in middle and older age the aorta continues to remodel to a larger diameter, thinning the pool of permanent elastin fibers, increasing intramural wall stress and resulting in the transfer of load bearing onto stiffer collagen fibers. Whereas aortic stiffening in early middle age may be a compensatory mechanism to normalize intramural wall stress and therefore theoretically "good" early in the life span, the negative clinical consequences of accelerated aortic stiffening beyond middle age far outweigh any earlier physiological benefit. Indeed, aortic stiffness and the loss of the "windkessel effect" with advancing age result in elevated pulsatile pressure and flow in downstream microvasculature that is associated with subclinical damage to high-flow, low-resistance organs such as brain, kidney, retina, and heart. The mechanisms of aortic stiffness include alterations in extracellular matrix proteins (collagen deposition, elastin fragmentation), increased arterial tone (oxidative stress and inflammation-related reduced vasodilators and augmented vasoconstrictors; enhanced sympathetic activity), arterial calcification, vascular smooth muscle cell stiffness, and extracellular matrix glycosaminoglycans. Given the rapidly aging population of the United States, aortic stiffening will likely contribute to substantial CVD burden over the next 2-3 decades unless new therapeutic targets and interventions are identified to prevent the potential avalanche of clinical sequelae related to age-related aortic stiffness.
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Affiliation(s)
- Gary L Pierce
- Department of Health and Human Physiology, University of Iowa, Iowa City, Iowa
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa
- Abboud Cardiovascular Research Center, University of Iowa, Iowa City, Iowa
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | - Thais A Coutinho
- Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Divisions of Cardiology and Cardiac Prevention and Rehabilitation, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - Lyndsey E DuBose
- Division of Geriatrics, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Anthony J Donato
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
- Department of Biochemistry, University of Utah, Salt Lake City, Utah
- Geriatric Research Education and Clinical Center, VA Salt Lake City, Salt Lake City, Utah
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Meester JAN, De Kinderen P, Verstraeten A, Loeys BL. The role of biglycan in the healthy and thoracic aneurysmal aorta. Am J Physiol Cell Physiol 2022; 322:C1214-C1222. [PMID: 35476501 DOI: 10.1152/ajpcell.00036.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The class I small leucine-rich proteoglycan biglycan is a crucial structural extracellular matrix component that interacts with a wide range of extracellular matrix molecules. In addition, biglycan is involved in sequestering growth factors such as TGF-β and BMPs and thereby regulating pathway activity. Biglycan consists of a 42-kDa core protein linked to two glycosaminoglycan side chains and both are involved in protein interactions. Biglycan is encoded by the BGN gene located on the X-chromosome and is expressed in various tissues, including vascular tissue, skin, brain, kidney lung, the immune system and the musculoskeletal system. Although an increasing amount of data on the biological function of biglycan in the vasculature has been produced, its role in thoracic aortic aneurysms is still not fully elucidated. This review focusses on the role of biglycan in the healthy thoracic aorta and the development of thoracic aortic aneurysm and dissections in both mice and humans.
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Affiliation(s)
- Josephina A N Meester
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Pauline De Kinderen
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Aline Verstraeten
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Bart L Loeys
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium.,Department of Clinical Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
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Ghadie NM, St-Pierre JP, Labrosse MR. Intramural Distributions of GAGs and Collagen vs. Opening Angle of the Intact Porcine Aortic Wall. Ann Biomed Eng 2022; 50:157-168. [PMID: 35028784 DOI: 10.1007/s10439-022-02901-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 01/01/2022] [Indexed: 11/28/2022]
Abstract
The heterogeneity and contribution of collagen and elastin to residual stresses have been thoroughly studied, but more recently, glycosaminoglycans (GAGs) also emerged as potential regulators. In this study, the opening angle of aortic rings (an indicator of circumferential residual stresses) and the mural distributions of sulfated GAGs (sGAG), collagen, and elastin were quantified in the ascending, aortic arch and descending thoracic regions of 5- to 6-month-old pigs. The opening angle correlated positively with the aortic ring's mean radius and thickness, with good and moderate correlations respectively. The correlations between the sGAG, collagen, elastin, and collagen:sGAG ratio and the opening angle were evaluated to identify aortic compositional factors that could play roles in regulating circumferential residual stresses. The total collagen:sGAG ratio displayed the strongest correlation with the opening angle (r = - 0.715, p < 0.001), followed by the total sGAG content which demonstrated a good correlation (r = 0.623, p < 0.001). Additionally, the intramural gradients of collagen, sGAG and collagen:sGAG correlated moderately with the opening angle. We propose that, in addition to the individual role sGAG play through their content and intramural gradient, the interaction between collagen and sGAG should be considered when evaluating circumferential residual stresses in the aorta.
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Affiliation(s)
- Noor M Ghadie
- Mechanical Engineering Department, University of Ottawa, Ottawa, ON, K1N6N5, Canada
| | - Jean-Philippe St-Pierre
- Chemical and Biological Engineering Department, University of Ottawa, Ottawa, ON, K1N6N5, Canada
| | - Michel R Labrosse
- Mechanical Engineering Department, University of Ottawa, Ottawa, ON, K1N6N5, Canada. .,Department of Cardiac Surgery, University of Ottawa Heart Institute, Ottawa, ON, K1Y4W7, Canada.
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