1
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Bazaid A, Zhang F, Zhang Q, Neumayer S, Denning D, Habelitz S, Marina Ferreira A, Rodriguez BJ. Electromechanical Coupling in Collagen Measured under Increasing Relative Humidity. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6034. [PMID: 37687727 PMCID: PMC10488372 DOI: 10.3390/ma16176034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/22/2023] [Accepted: 08/31/2023] [Indexed: 09/10/2023]
Abstract
The functional role of collagen piezoelectricity has been under debate since the discovery of piezoelectricity in bone in 1957. The possibility that piezoelectricity plays a role in bone remodeling has generated interest in the investigation of this effect in relevant physiological conditions; however, there are conflicting reports as to whether collagen is piezoelectric in a humid environment. In macroscale measurements, the piezoelectricity in hydrated tendon has been shown to be insignificant compared to dehydrated tendon, whereas, at the nanoscale, the piezoelectric effect has been observed in both dry and wet bone using piezoresponse force microscopy (PFM). In this work, the electromechanical properties of type I collagen from a rat tail tendon have been investigated at the nanoscale as a function of humidity using lateral PFM (LPFM) for the first time. The relative humidity (RH) was varied from 10% to 70%, allowing the piezoelectric behavior to be studied dry, humid, as well as in the hydrated range for collagen in physiological bone (12% moisture content, corresponding to 40-50% RH). The results show that collagen piezoresponse can be measured across the humidity range studied, suggesting that piezoelectricity remains a property of collagen at a biologically relevant humidity.
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Affiliation(s)
- Arwa Bazaid
- School of Physics and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin D04 V1W8, Ireland; (A.B.); (F.Z.); (Q.Z.); (S.N.)
| | - Fengyuan Zhang
- School of Physics and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin D04 V1W8, Ireland; (A.B.); (F.Z.); (Q.Z.); (S.N.)
| | - Qiancheng Zhang
- School of Physics and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin D04 V1W8, Ireland; (A.B.); (F.Z.); (Q.Z.); (S.N.)
| | - Sabine Neumayer
- School of Physics and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin D04 V1W8, Ireland; (A.B.); (F.Z.); (Q.Z.); (S.N.)
| | - Denise Denning
- FOCAS Research Institute, Technological University Dublin, City Campus, Camden Row, Dublin D04 V1W8, Ireland;
| | - Stefan Habelitz
- Department of Preventative and Restorative Dental Sciences, School of Dentistry, University of California, San Francisco, CA 94143, USA;
| | - Ana Marina Ferreira
- School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK;
| | - Brian J. Rodriguez
- School of Physics and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin D04 V1W8, Ireland; (A.B.); (F.Z.); (Q.Z.); (S.N.)
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2
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Assessing Collagen D-Band Periodicity with Atomic Force Microscopy. MATERIALS 2022; 15:ma15041608. [PMID: 35208148 PMCID: PMC8877100 DOI: 10.3390/ma15041608] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 02/16/2022] [Accepted: 02/17/2022] [Indexed: 02/01/2023]
Abstract
The collagen superfamily includes more than fifty collagen and/or collagen-like proteins with fibril-forming collagen type I being the most abundant protein within the extracellular matrix. Collagen type I plays a crucial role in a variety of functions, it has been associated with many pathological conditions and it is widely used due to its unique properties. One unique nano-scale characteristic of natural occurring collagen type I fibers is the so-called D-band periodicity, which has been associated with collagen natural structure and properties, while it seems to play a crucial role in the interactions between cells and collagen and in various pathological conditions. An accurate characterization of the surface and structure of collagen fibers, including D-band periodicity, on collagen-based tissues and/or (nano-)biomaterials can be achieved by Atomic Force Microscopy (AFM). AFM is a scanning probe microscope and is among the few techniques that can assess D-band periodicity. This review covers issues related to collagen and collagen D-band periodicity and the use of AFM for studying them. Through a systematic search in databases (PubMed and Scopus) relevant articles were identified. The study of these articles demonstrated that AFM can offer novel information concerning D-band periodicity. This study highlights the importance of studying collagen D-band periodicity and proves that AFM is a powerful tool for investigating a number of different properties related to collagen D-band periodicity.
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3
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Al Makhzoomi AK, Kirk TB, Allison GT. An AFM study of the nanostructural response of New Zealand white rabbit Achilles tendons to cyclic loading. Microsc Res Tech 2021; 85:728-737. [PMID: 34632676 DOI: 10.1002/jemt.23944] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/14/2021] [Accepted: 09/09/2021] [Indexed: 01/21/2023]
Abstract
The nanostructural response of New Zealand white rabbit Achilles tendons to a fatigue damage model was assessed quantitatively and qualitatively using the endpoint of dose assessments of each tendon from our previous study. The change in mechanical properties was assessed concurrently with nanostructural change in the same non-viable intact tendon. Atomic force microscopy was used to study the elongation of D-periodicities, and the changes were compared both within the same fibril bundle and between fibril bundles. D-periodicities increased due to both increased strain and increasing numbers of fatigue cycles. Although no significant difference in D-periodicity lengthening was found between fibril bundles, the lengthening of D-periodicity correlated strongly with the overall tendon mechanical changes. The accurate quantification of fibril elongation in response to macroscopic applied strain assisted in assessing the complex structure-function relationship in Achilles tendons.
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Affiliation(s)
- Anas K Al Makhzoomi
- School of Allied Health, Faculty of Health Science, Curtin University, Perth, Western Australia, Australia
| | - Thomas B Kirk
- School of Science, Engineering and Technology, RMIT University Vietnam, Ho Chi Minh City, Vietnam
| | - Garry T Allison
- Associate Deputy Vice-Chancellor, Research Excellence, Curtin University, Perth, Western Australia, Australia
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4
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Wilkinson HN, Hardman MJ. A role for estrogen in skin ageing and dermal biomechanics. Mech Ageing Dev 2021; 197:111513. [PMID: 34044023 DOI: 10.1016/j.mad.2021.111513] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/20/2021] [Accepted: 05/22/2021] [Indexed: 01/11/2023]
Abstract
The skin is the body's primary defence against the external environment, preventing infection and desiccation. Therefore, alterations to skin homeostasis, for example with skin ageing, increase susceptibility to skin disease and injury. Skin biological ageing is uniquely influenced by a combination of intrinsic and extrinsic (primarily photoageing) factors, with differential effects on skin structure and function. Interestingly, skin architecture rapidly changes following the menopause, as a direct result of reduced circulating 17β-estradiol. The traditional clinical benefit of estrogens are supported by recent experimental data, where 17β-estradiol supplementation prevents age-related decline in the skin's structural and mechanical properties. However, the off-target effects of 17β-estradiol continue to challenge therapeutic application. Here we discuss how ageing alters the physiological and structural properties of the dermal extracellular matrix, and explore how estrogen receptor-targeted therapies may restore the mechanical defects associated with skin ageing.
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Affiliation(s)
- Holly N Wilkinson
- Centre for Atherothrombosis and Metabolic Disease, Hull York Medical School, The University of Hull, HU6 7RX, United Kingdom
| | - Matthew J Hardman
- Centre for Atherothrombosis and Metabolic Disease, Hull York Medical School, The University of Hull, HU6 7RX, United Kingdom.
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5
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Wan Y, Gao Y, Shao J, Tumarbekova A, Zhang D, Zhu J. Effects of ultrasound and thermal treatment on the ultrastructure of collagen fibers from bovine tendon using atomic force microscopy. Food Chem 2021; 347:128985. [PMID: 33476920 DOI: 10.1016/j.foodchem.2020.128985] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 12/08/2020] [Accepted: 12/13/2020] [Indexed: 01/22/2023]
Abstract
As the most important tenderness related protein in mammal, there are few studies on how the nanoscale morphology of collagen I in tissues is related to traditional meat processing. The ultrastructure and mechanical characteristics of collagen fibers in tendon with different treatments have been explored in this study. Collagen fibers in homogenate group and acetic acid group were treated with ultrasound and thermal treatment. The nanoscale morphology of collagen fiber in homogenate group became granular at 60 °C and gelatin was formed at 70 °C. The collagen fibers extracted from acetic acid are unstable and easier to break under the same processing parameters, when compared with homogenated collagen fibers in both ultrasound and thermal treatment. The results suggested that acetic acid can disassemble the salt bond and Schiff-base in collagen, and the collagen fibers became loose but the triple helix structure remained integrity.
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Affiliation(s)
- Yunfei Wan
- Laboratory of Agricultural & Food Biomechanics, Institute of Biophysics, College of Science, Northwest A&F University, Yangling, Shanxi 712100, China; Laboratory of Muscle & Meat Biomechanics, National Beef Cattle Improvement Center, Northwest A&F University, Yangling, Shanxi 712100, China
| | - Yongfang Gao
- Laboratory of Agricultural & Food Biomechanics, Institute of Biophysics, College of Science, Northwest A&F University, Yangling, Shanxi 712100, China; Laboratory of Muscle & Meat Biomechanics, National Beef Cattle Improvement Center, Northwest A&F University, Yangling, Shanxi 712100, China
| | - Jianhang Shao
- Laboratory of Agricultural & Food Biomechanics, Institute of Biophysics, College of Science, Northwest A&F University, Yangling, Shanxi 712100, China; Laboratory of Muscle & Meat Biomechanics, National Beef Cattle Improvement Center, Northwest A&F University, Yangling, Shanxi 712100, China
| | - Aidana Tumarbekova
- Laboratory of Agricultural & Food Biomechanics, Institute of Biophysics, College of Science, Northwest A&F University, Yangling, Shanxi 712100, China
| | - Dequan Zhang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs, Beijing 100193, China.
| | - Jie Zhu
- Laboratory of Agricultural & Food Biomechanics, Institute of Biophysics, College of Science, Northwest A&F University, Yangling, Shanxi 712100, China; Laboratory of Muscle & Meat Biomechanics, National Beef Cattle Improvement Center, Northwest A&F University, Yangling, Shanxi 712100, China.
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6
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Effects of Estradiol on Expression of Estrogen Receptor and Collagen mRNAs in Chick Skin. J Poult Sci 2021; 59:162-167. [PMID: 35528379 PMCID: PMC9039147 DOI: 10.2141/jpsa.0210093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/02/2021] [Indexed: 11/21/2022] Open
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7
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Misiakiewicz-Has K, Zawiślak A, Pilutin A, Kolasa-Wołosiuk A, Szumilas P, Duchnik E, Wiszniewska B. Morphological and Functional Changes in Skin of Adult Male Rats Chronically Treated with Letrozole, a Nonsteroidal Inhibitor of Cytochrome P450 Aromatase. Acta Histochem Cytochem 2020; 53:99-111. [PMID: 33177782 PMCID: PMC7642481 DOI: 10.1267/ahc.20009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 07/08/2020] [Indexed: 11/22/2022] Open
Abstract
Skin is a target for hormones and a site of hormone production. Aromatase inhibitors such as letrozole reduce circulating estrogen. The aim of the study was to investigate the morphology of the dermis and immunoexpression of androgen receptor (AR), estrogen receptor α and β (ERα, ERβ), luteinizing hormone receptor (LHR), follicle-stimulating hormone receptor (FSHR), and cytochrome P450 aromatase (P450arom) in male rats with a deficit of estradiol. Experiments were performed on skin of 12 male rats. Rats in the experimental group received per os letrozole for 6 months. For morphological analysis, van Gieson, Sirius Red and orcein staining of sections was performed. In immunohistochemistry, reactions with specific antibodies (anti-P450arom, LHR, FSHR, ERα, ERβ) were used. In morphometric analysis, sections were stained with hematoxylin and eosin. Differences between groups were assessed by Mann-Whitney U-test. There were no differences in the diameter of collagen fibers. The dermis of letrozole-treated animals showed areas without collagen fibers, and expression of P450arom, ERα and ERβ was diminished in the skin of these animals. This study indicates that estrogens exert an effect via ERs that has a role in maintaining proper skin morphology in males, together with androgen. This is also the first documented expression of FSHR in the skin of male rats.
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Affiliation(s)
| | - Alicja Zawiślak
- Department of Interdisciplinary Dentistry, Pomeranian Medical University in Szczecin
| | - Anna Pilutin
- Department of Histology and Embryology, Pomeranian Medical University in Szczecin
| | | | - Paweł Szumilas
- Department of Social Medicine and Public Health, Pomeranian Medical University in Szczecin
| | - Ewa Duchnik
- Department of Dermatology and Venereology, Pomeranian Medical University in Szczecin
| | - Barbara Wiszniewska
- Department of Histology and Embryology, Pomeranian Medical University in Szczecin
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8
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Cauble MA, Mancini NS, Kalinowski J, Lykotrafitis G, Moss IL. Atomic force microscopy imaging for nanoscale and microscale assessments of extracellular matrix in intervertebral disc and degeneration. JOR Spine 2020; 3:e1125. [PMID: 33015582 PMCID: PMC7524250 DOI: 10.1002/jsp2.1125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 07/07/2020] [Accepted: 08/30/2020] [Indexed: 01/07/2023] Open
Abstract
Degeneration of the intervertebral disc (IVD) is a condition that is often associated with debilitating back pain. There are no disease-modifying treatments available to halt the progression of this ubiquitous disorder. This is partly due to a lack of understanding of extracellular matrix (ECM) changes that occur at the micro- and nanometer size scales as the disease progresses. Over the past decade, atomic force microscopy (AFM) has been utilized as a tool to investigate the impact of disease on nanoscale structure of ECM in bone, skin, tendon, and dentin. We have expanded this methodology to include the IVD and report the first quantitative analysis of ECM structure at submicron size scales in a murine model for progressive IVD degeneration. Collagen D-spacing, a metric of nanoscale structure at the fibril level, was observed as a distribution of values with an overall average value of 62.5 ± 2.5 nm. In degenerative discs, the fibril D-spacing distribution shifted towards higher values in both the annulus fibrosus and nucleus pulposus (NP) (P < .05). A novel microstructural feature, collagen toroids, defined by a topographical pit enclosed by fibril-forming matrix was observed in the NP. With degeneration, these microstructures became more numerous and the morphology was altered from circular (aspect ratio 1.0 ± 0.1) to oval (aspect ratio 1.5 ± 0.4), P < .005. These analyses provide ECM structural details of the IVD at size scales that have historically been missing in studies of disc degeneration. Knowledge gained from these insights may aid the development of novel disease-modifying therapeutics.
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Affiliation(s)
- Meagan A Cauble
- UConn Health Department of Orthopaedic Surgery Musculoskeletal Institute Farmington Connecticut USA
| | - Nickolas S Mancini
- UConn Health Department of Orthopaedic Surgery Musculoskeletal Institute Farmington Connecticut USA
| | - Judith Kalinowski
- UConn Health Department of Orthopaedic Surgery Musculoskeletal Institute Farmington Connecticut USA
| | - George Lykotrafitis
- Department of Mechanical Engineering University of Connecticut Storrs Connecticut USA
| | - Isaac L Moss
- UConn Health Department of Orthopaedic Surgery Musculoskeletal Institute Farmington Connecticut USA
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9
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Sasso GRDS, Florencio-Silva R, da Fonseca CCN, Cezar LC, Carbonel AAF, Gil CD, Simões MDJ, Girão MJBC. Effects of estrogen deficiency followed by streptozotocin-induced diabetes on periodontal tissues of female rats. J Mol Histol 2020; 51:353-365. [PMID: 32488735 DOI: 10.1007/s10735-020-09885-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 05/29/2020] [Indexed: 01/18/2023]
Abstract
Although both estrogen deficiency and diabetes contribute to periodontal tissue deterioration, the combined effects of these conditions on periodontium is unknown. Thus, we analyzed the combined effects of ovariectomy followed by streptozotocin (STZ)-induced diabetes on periodontal tissues of rats. Twenty adult rats were ovariectomized (OVX) or SHAM-operated (SHAM). After 3 weeks, the rats received an intraperitoneal injection of STZ (60 mg/kg/body weight) to induce diabetes or vehicle (blank) solution. The groups were assigned as follows (n = 5): SHAM-vehicle (SHAM), OVX-vehicle (OVX), SHAM + STZ (SHAM-Di), and OVX + STZ (OVX-Di). Seven weeks post-diabetes induction, the rats were euthanized. Blood samples were collected for glucose measurements and maxillae were processed for paraffin embedding. Sections stained with hematoxylin/eosin, Masson's trichrome, and picrosirius-red were used for alveolar bone loss and collagen fiber analysis in the lamina propria. Immunohistochemistry was performed for runt-related transcription factor 2 (Runx2), matrix metalloproteinase 9 (MMP-9), and tryptase detection. Alveolar bone loss and fewer collagen fibers were observed in the OVX-Di group, collagen fibers with irregular organization, and MMP-9 immunoreactivity were more evident in diabetic groups, and MMP-9-positive osteoclasts on alveolar bone surface were noticed in all groups. The OVX-Di group showed lower Runx2 immunoreactivity (osteoblast formation marker), and more tryptase-positive cells (mast cell marker) in the alveolar bone marrow. Our results indicate that estrogen depletion, followed by STZ-induced diabetes, promotes periodontal tissue deterioration that is more evident than both interventions applied alone. Furthermore, our results points to a possible participation of bone-derived mast cells in this process.
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Affiliation(s)
- Gisela Rodrigues da Silva Sasso
- Departamento de Ginecologia, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil.
- Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil.
| | - Rinaldo Florencio-Silva
- Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil
| | - Caio Cesar Navarrete da Fonseca
- Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil
| | - Luana Carvalho Cezar
- Faculdade de Medicina Veterinária e Zootecnia, Patologia Experimental e Comparada, Universidade de São Paulo, São Paulo, Brazil
| | - Adriana Aparecida Ferraz Carbonel
- Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil
| | - Cristiane Damas Gil
- Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil
| | - Manuel de Jesus Simões
- Departamento de Ginecologia, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil
- Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil
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10
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Sun Y, Vu LH, Chew N, Puthucheary Z, Cove ME, Zeng K. A Study of Perturbations in Structure and Elastic Modulus of Bone Microconstituents Using Bimodal Amplitude Modulated-Frequency Modulated Atomic Force Microscopy. ACS Biomater Sci Eng 2018; 5:478-486. [DOI: 10.1021/acsbiomaterials.8b01087] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Yao Sun
- Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, 117576, Singapore
| | - Lien Hong Vu
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block Level 10, Singapore 119228
| | - Nicholas Chew
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block Level 10, Singapore 119228
| | - Zudin Puthucheary
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block Level 10, Singapore 119228
- Division of Critical Care, Institute of Sports and Exercise Health, University College London Hospitals, U.K., and Centre for Human Health and Performance, University College London, London WC1E 6BT, United Kingdom
| | - Matthew E. Cove
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block Level 10, Singapore 119228
| | - Kaiyang Zeng
- Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, 117576, Singapore
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11
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Merzel R, Orr BG, Banaszak Holl MM. Distributions: The Importance of the Chemist's Molecular View for Biological Materials. Biomacromolecules 2018; 19:1469-1484. [PMID: 29663809 PMCID: PMC5954352 DOI: 10.1021/acs.biomac.8b00375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 04/15/2018] [Indexed: 12/29/2022]
Abstract
Characterization of materials with biological applications and assessment of physiological effects of therapeutic interventions are critical for translating research to the clinic and preventing adverse reactions. Analytical techniques typically used to characterize targeted nanomaterials and tissues rely on bulk measurement. Therefore, the resulting data represent an average structure of the sample, masking stochastic (randomly generated) distributions that are commonly present. In this Perspective, we examine almost 20 years of work our group has done in different fields to characterize and control distributions. We discuss the analytical techniques and statistical methods we use and illustrate how we leverage them in tandem with other bulk techniques. We also discuss the challenges and time investment associated with taking such a detailed view of distributions as well as the risks of not fully appreciating the extent of heterogeneity present in many systems. Through three case studies showcasing our research on conjugated polymers for drug delivery, collagen in bone, and endogenous protein nanoparticles, we discuss how identification and characterization of distributions, i.e., a molecular view of the system, was critical for understanding the observed biological effects. In all three cases, data would have been misinterpreted and insights missed if we had only relied upon spatially averaged data. Finally, we discuss how new techniques are starting to bridge the gap between bulk and molecular level analysis, bringing more opportunity and capacity to the research community to address the challenges of distributions and their roles in biology, chemistry, and the translation of science and engineering to societal challenges.
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Affiliation(s)
- Rachel
L. Merzel
- Department
of Chemistry and Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Bradford G. Orr
- Department
of Chemistry and Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
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12
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Chen JH, Wu SC, Chen HJ, Kao CH, Tseng CH, Tsai CH. Risk of developing pressure sore in amyotrophic lateral sclerosis patients - a nationwide cohort study. J Eur Acad Dermatol Venereol 2018; 32:1589-1596. [PMID: 29512203 DOI: 10.1111/jdv.14911] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 02/08/2018] [Indexed: 11/29/2022]
Abstract
BACKGROUND Prior investigations with few cases have disclosed lack of pressure sore (PrS) formation was characteristic in amyotrophic lateral sclerosis (ALS) patients. However, studies with larger samples are lacking to ascertain this concept. OBJECTIVE To investigate whether patients with ALS have higher risk of PrS. METHODS Utilizing a Taiwan National Insurance claims data set with 23 million participants, we extracted 514 patients with ALS and 2056 controls from 1 January 2000 to 31 December 2008. Both groups were followed up until PrS occurrence during study period (2000-2011). The PrS risk was calculated with Cox proportional regression model. RESULTS The patients with ALS had a greater PrS risk (adjusted hazard ratio [aHR] = 8.82, 95% confidence interval [CI] = 4.90-15.9, P < 0.001) than the controls did. PrS risk was much higher in ALS women (aHR = 26.6, 95% CI = 9.05-78.2, P < 0.001) than in ALS men (aHR = 4.38, 95% CI = 1.99-9.68, P < 0.001). Besides, in people aged 20-54, ALS was linked with a much greater PrS risk (aHR = 27.7, 95% CI = 5.79-132, P < 0.001) than in those aged ≥55 (aHR = 6.10, 95% CI = 3.10-12.0, P < 0.001). CONCLUSIONS Amyotrophic lateral sclerosis is discovered to be correlated with an enhanced PrS risk. For PrS prevention, it is needed to pay more attention to the management of the patients with ALS, particularly in women and those with relatively younger age. Further investigations are needed to confirm the findings in this study.
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Affiliation(s)
- J-H Chen
- Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan.,School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan
| | - S-C Wu
- School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.,Trauma and Emergency Center, China Medical University Hospital, Taichung, Taiwan
| | - H-J Chen
- Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan.,College of Medicine, China Medical University, Taichung, Taiwan
| | - C-H Kao
- School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.,Department of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan
| | - C-H Tseng
- School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.,Department of Neurology, China Medical University Hospital, Taichung, Taiwan
| | - C-H Tsai
- School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.,Department of Neurology, China Medical University Hospital, Taichung, Taiwan
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13
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Eckersley A, Mellody KT, Pilkington S, Griffiths CEM, Watson REB, O'Cualain R, Baldock C, Knight D, Sherratt MJ. Structural and compositional diversity of fibrillin microfibrils in human tissues. J Biol Chem 2018; 293:5117-5133. [PMID: 29453284 PMCID: PMC5892578 DOI: 10.1074/jbc.ra117.001483] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 02/07/2018] [Indexed: 12/11/2022] Open
Abstract
Elastic fibers comprising fibrillin microfibrils and elastin are present in many tissues, including the skin, lungs, and arteries, where they confer elasticity and resilience. Although fibrillin microfibrils play distinct and tissue-specific functional roles, it is unclear whether their ultrastructure and composition differ between elastin-rich (skin) and elastin-poor (ciliary body and zonule) organs or after in vitro synthesis by cultured cells. Here, we used atomic force microscopy, which revealed that the bead morphology of fibrillin microfibrils isolated from the human eye differs from those isolated from the skin. Using newly developed pre-MS preparation methods and LC-MS/MS, we detected tissue-specific regions of the fibrillin-1 primary structure that were differentially susceptible to proteolytic extraction. Comparing tissue- and culture-derived microfibrils, we found that dermis- and dermal fibroblast–derived fibrillin microfibrils differ in both bead morphology and periodicity and also exhibit regional differences in fibrillin-1 proteolytic susceptibility. In contrast, collagen VI microfibrils from the same dermal or fibroblast samples were invariant in ultrastructure (periodicity) and protease susceptibility. Finally, we observed that skin- and eye-derived microfibril suspensions were enriched in elastic fiber– and basement membrane–associated proteins, respectively. LC-MS/MS also identified proteins (such as calreticulin and protein-disulfide isomerase) that are potentially fundamental to fibrillin microfibril biology, regardless of their tissue source. Fibrillin microfibrils synthesized in cell culture lacked some of these key proteins (MFAP2 and -4 and fibrillin-2). These results showcase the structural diversity of these key extracellular matrix assemblies, which may relate to their distinct roles in the tissues where they reside.
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Affiliation(s)
| | - Kieran T Mellody
- From the Division of Cell Matrix Biology and Regenerative Medicine
| | | | - Christopher E M Griffiths
- the Division of Musculoskeletal and Dermatological Sciences.,the NIHR Manchester Biomedical Research Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester M13 9PT, United Kingdom
| | - Rachel E B Watson
- the Division of Musculoskeletal and Dermatological Sciences.,the NIHR Manchester Biomedical Research Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester M13 9PT, United Kingdom
| | | | - Clair Baldock
- From the Division of Cell Matrix Biology and Regenerative Medicine.,the Wellcome Trust Centre for Cell-Matrix Research, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom and
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Chen J, Ahn T, Colón-Bernal ID, Kim J, Banaszak Holl MM. The Relationship of Collagen Structural and Compositional Heterogeneity to Tissue Mechanical Properties: A Chemical Perspective. ACS NANO 2017; 11:10665-10671. [PMID: 29112404 DOI: 10.1021/acsnano.7b06826] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Collagen is the primary protein component in mammalian connective tissues. Over the last 20 years, evidence has mounted that collagen matrices exhibit substantial heterogeneity in their hierarchical structures and that this heterogeneity plays important roles in both structure and function. Herein, an overview of studies addressing the nanoscale compositional and structural heterogeneity is provided and connected to work exploring the mechanical implications for a number of tissues.
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Affiliation(s)
- Junjie Chen
- Department of Chemistry, ‡Macromolecular Science and Engineering, and §Department of Biomedical Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Taeyong Ahn
- Department of Chemistry, ‡Macromolecular Science and Engineering, and §Department of Biomedical Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Isabel D Colón-Bernal
- Department of Chemistry, ‡Macromolecular Science and Engineering, and §Department of Biomedical Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Jinhee Kim
- Department of Chemistry, ‡Macromolecular Science and Engineering, and §Department of Biomedical Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Mark M Banaszak Holl
- Department of Chemistry, ‡Macromolecular Science and Engineering, and §Department of Biomedical Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
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15
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Cauble MA, Muckley MJ, Fang M, Fessler JA, Welch K, Rothman ED, Orr BG, Duong LT, Holl MMB. Estrogen depletion and drug treatment alter the microstructure of type I collagen in bone. Bone Rep 2016; 5:243-251. [PMID: 28580393 PMCID: PMC5440968 DOI: 10.1016/j.bonr.2016.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 08/15/2016] [Accepted: 08/25/2016] [Indexed: 12/22/2022] Open
Abstract
The impact of estrogen depletion and drug treatment on type I collagen fibril nanomorphology and collagen fibril packing (microstructure) was evaluated by atomic force microscopy (AFM) using an ovariectomized (OVX) rabbit model of estrogen deficiency induced bone loss. Nine month-old New Zealand white female rabbits were treated as follows: sham-operated (Sham; n = 11), OVX + vehicle (OVX + Veh; n = 12), OVX + alendronate (ALN, 600 μg/kg/wk., s.c.; n = 12), and OVX + cathepsin-K inhibitor L-235 (CatKI, 10 mg/kg, daily, p.o.; n = 13) in prevention mode for 27 weeks. Samples from the cortical femur and trabecular lumbar vertebrae were polished, demineralized, and imaged using AFM. Auto-correlation of image patches was used to generate a vector field for each image that mathematically approximated the collagen fibril alignment. This vector field was used to compute an information-theoretic entropy that was employed as a quantitative fibril alignment parameter (FAP) to allow image-to-image and sample-to-sample comparison. For all samples, no change was observed in the average FAP values; however significant differences in the distribution of FAP values were observed. In particular, OVX + Veh lumbar vertebrae samples contained a tail of lower FAP values representing regions of greater fibril alignment. OVX + ALN treatment resulted in a FAP distribution with a tail indicating greater alignment for cortical femur and less alignment for trabecular lumbar vertebrae. OVX + CatKI treatment gave a distribution of FAP values with a tail indicating less alignment for cortical femur and no change for trabecular lumbar vertebrae. Fibril alignment was also evaluated by considering when a fibril was part of discrete bundles or sheets (classified as parallel) or not (classified as oblique). For this analysis, the percentage of parallel fibrils in cortical femur for the OVX group was 17% lower than the Sham group. OVX + ALN treatment partially prevented the proportion of parallel fibrils from decreasing and OVX + CatKI treatment completely prevented a change. In trabecular lumbar vertebrae, there was no difference in the percentage of parallel fibrils between Sham and any of the other treatment groups.
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Affiliation(s)
- Meagan A. Cauble
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Matthew J. Muckley
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Ming Fang
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Jeffrey A. Fessler
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, USA
| | - Kathleen Welch
- Center for Statistical Consultation and Research (CSCAR), University of Michigan, Ann Arbor, MI, USA
| | - Edward D. Rothman
- Center for Statistical Consultation and Research (CSCAR), University of Michigan, Ann Arbor, MI, USA
- Department of Statistics, University of Michigan, Ann Arbor, MI, USA
| | - Bradford G. Orr
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - Le T. Duong
- Bone Biology Group, Merck Research Laboratories, West Point, PA, USA
| | - Mark M. Banaszak Holl
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI, USA
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Combined MSC and GLP-1 Therapy Modulates Collagen Remodeling and Apoptosis following Myocardial Infarction. Stem Cells Int 2016; 2016:7357096. [PMID: 28003833 PMCID: PMC5149702 DOI: 10.1155/2016/7357096] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 09/29/2016] [Accepted: 10/19/2016] [Indexed: 11/18/2022] Open
Abstract
Background. Mesenchymal stem cells (MSCs) and glucagon-like peptide-1 (GLP-1) are being tested as treatment strategies for myocardial infarction (MI); however, their mechanisms in the heart are not fully understood. Methods. We examined the effects of MSCs, either native, or engineered to secrete a GLP-1 fusion protein (MSCs ± GLP-1), on human cardiomyocyte apoptosis in vitro. The effect on cardiac remodeling when encapsulated in alginate beads (CellBeads-MSC and CellBeads-MSC + GLP-1) was also evaluated in a pig MI model, whereby pigs were treated with Empty Beads, CellBeads-MSC, or CellBeads-MSC + GLP-1 and sacrificed at one or four weeks following MI. Results. MSC + GLP-1 conditioned media demonstrated antiapoptotic effects on ischaemic human cardiomyocytes in vitro. In vivo, qRT-PCR revealed large changes in the expression of several genes involved in extracellular matrix remodeling, which were altered following MSC ± GLP treatment. After four weeks, infarcted areas were imaged using atomic force microscopy, demonstrating significant alterations between groups in the structure of collagen fibrils and resulting scar. Conclusions. These data demonstrate that MSCs ± GLP-1 exhibit modulatory effects on healing post-MI, affecting both apoptosis and collagen scar formation. These data support the premise that both MSCs and GLP-1 could be beneficial in MI treatment.
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Hammond MA, Laine TJ, Berman AG, Wallace JM. Treadmill Exercise Improves Fracture Toughness and Indentation Modulus without Altering the Nanoscale Morphology of Collagen in Mice. PLoS One 2016; 11:e0163273. [PMID: 27655444 PMCID: PMC5031456 DOI: 10.1371/journal.pone.0163273] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 09/05/2016] [Indexed: 01/22/2023] Open
Abstract
The specifics of how the nanoscale properties of collagen (e.g., the crosslinking profile) affect the mechanical integrity of bone at larger length scales is poorly understood despite growing evidence that collagen’s nanoscale properties are altered with disease. Additionally, mass independent increases in postyield displacement due to exercise suggest loading-induced improvements in bone quality associated with collagen. To test whether disease-induced reductions in bone quality driven by alterations in collagen can be rescued or prevented via exercise-mediated changes to collagen’s nanoscale morphology and mechanical properties, the effects of treadmill exercise and β-aminopropionitrile treatment were investigated. Eight week old female C57BL/6 mice were given a daily subcutaneous injection of either 164 mg/kg β-aminopropionitrile or phosphate buffered saline while experiencing either normal cage activity or 30 min of treadmill exercise for 21 consecutive days. Despite differences in D-spacing distribution (P = 0.003) and increased cortical area (tibial: P = 0.005 and femoral: P = 0.015) due to β-aminopropionitrile treatment, an overt mechanical disease state was not achieved as there were no differences in fracture toughness or 4 point bending due to β-aminopropionitrile treatment. While exercise did not alter (P = 0.058) the D-spacing distribution of collagen or prevent (P < 0.001) the β-aminopropionitrile-induced changes present in the unexercised animals, there were differential effects in the distribution of the reduced elastic modulus due to exercise between control and β-aminopropionitrile-treated animals (P < 0.001). Fracture toughness was increased (P = 0.043) as a main effect of exercise, but no significant differences due to exercise were observed using 4 point bending. Future studies should examine the potential for sex specific differences in the dose of β-aminopropionitrile required to induce mechanical effects in mice and the contributions of other nanoscale aspects of bone (e.g., the mineral–collagen interface) to elucidate the mechanism for the exercise-based improvements in fracture toughness observed here and the increased postyield deformation observed in other studies.
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Affiliation(s)
- Max A. Hammond
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States of America
| | - Tyler J. Laine
- Department of Biomedical Engineering, Indiana University–Purdue University Indianapolis, Indianapolis, IN, United States of America
| | - Alycia G. Berman
- Department of Biomedical Engineering, Indiana University–Purdue University Indianapolis, Indianapolis, IN, United States of America
| | - Joseph M. Wallace
- Department of Biomedical Engineering, Indiana University–Purdue University Indianapolis, Indianapolis, IN, United States of America
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, United States of America
- * E-mail:
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18
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Kim T, Sridharan I, Ma Y, Zhu B, Chi N, Kobak W, Rotmensch J, Schieber JD, Wang R. Identifying distinct nanoscopic features of native collagen fibrils towards early diagnosis of pelvic organ prolapse. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2015; 12:667-675. [PMID: 26656625 DOI: 10.1016/j.nano.2015.11.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 10/20/2015] [Accepted: 11/09/2015] [Indexed: 01/02/2023]
Abstract
UNLABELLED Pelvic organ prolapse (POP) is characterized by weakening of the connective tissues and loss of support for the pelvic organs. Collagen is the predominant, load-bearing protein within pelvic floor connective tissues. In this study, we examined the nanoscopic structures and biomechanics of native collagen fibrils in surgical, vaginal wall connective tissues from healthy women and POP patients. Compared to controls, collagen fibrils in POP samples were bulkier, more uneven in width and stiffer with aberrant D-period. Additionally, the ratio of collagen I (COLI) and collagen III (COLIII) is doubled in POP with a concomitant reduction of the amount of total collagen. Thus, POP is characterized by abnormal biochemical composition and biophysical characteristics of collagen fibrils that form a loose and fragile fiber network accountable for the weak load-bearing capability. The study identifies nanoscale alterations in collagen as diagnostic markers that could enable pre-symptomatic or early diagnosis of POP. FROM THE CLINICAL EDITOR Pelvic organ prolapse (POP) occurs due to abnormalities of the supporting connective tissues. The underlying alterations of collagen fibers in the connective tissues have not been studied extensively. In this article, the authors showed that collagen fibrils in POP patients were much different from normal controls. The findings may provide a framework for the diagnosis of other connective diseases.
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Affiliation(s)
- Taeyoung Kim
- Department of Chemistry, Illinois Institute of Technology, Chicago, IL, USA
| | | | - Yin Ma
- Department of Chemistry, Illinois Institute of Technology, Chicago, IL, USA
| | - Bofan Zhu
- Department of Chemistry, Illinois Institute of Technology, Chicago, IL, USA
| | - Naiwei Chi
- Department of Chemistry, Illinois Institute of Technology, Chicago, IL, USA
| | - William Kobak
- Department of Obstetrics and Gynecology, University of Illinois at Chicago, Chicago, IL, USA
| | - Jacob Rotmensch
- Department of Obstetrics and Gynecology, Rush University Medical School, Chicago, IL, USA
| | - Jay D Schieber
- Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, IL, USA
| | - Rong Wang
- Department of Chemistry, Illinois Institute of Technology, Chicago, IL, USA.
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19
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Campi G, Fratini M, Bukreeva I, Ciasca G, Burghammer M, Brun F, Tromba G, Mastrogiacomo M, Cedola A. Imaging collagen packing dynamics during mineralization of engineered bone tissue. Acta Biomater 2015; 23:309-316. [PMID: 26049151 DOI: 10.1016/j.actbio.2015.05.033] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 05/08/2015] [Accepted: 05/28/2015] [Indexed: 01/03/2023]
Abstract
The structure and organization of the Type I collagen microfibrils during mineral nanoparticle formation appear as the key factor for a deeper understanding of the biomineralization mechanism and for governing the bone tissue physical properties. In this work we investigated the dynamics of collagen packing during ex-vivo mineralization of ceramic porous hydroxyapatite implant scaffolds using synchrotron high resolution X-ray phase contrast micro-tomography (XPCμT) and synchrotron scanning micro X-ray diffraction (SμXRD). While XPCμT provides the direct 3D image of the collagen fibers network organization with micrometer spatial resolution, SμXRD allows to probe the structural statistical fluctuations of the collagen fibrils at nanoscale. In particular we imaged the lateral spacing and orientation of collagen fibrils during the anisotropic growth of mineral nanocrystals. Beyond throwing light on the bone regeneration multiscale process, this approach can provide important information in the characterization of tissue in health, aging and degeneration conditions. STATEMENT OF SIGNIFICANCE BONE grafts are the most common transplants after the blood transfusions. This makes the bone-tissue regeneration research of pressing scientific and social impact. Bone is a complex hierarchical structure, where the interplay of organic and inorganic mineral phases at different length scale (from micron to atomic scale) affect its functionality and health. Thus, the understanding of bone tissue regeneration requires to image its spatial-temporal evolution (i) with high spatial resolution and (ii) at different length scale. We exploited high spatial resolution X-ray Phase Contrast micro Tomography and Scanning micro X-ray Diffraction in order to get new insight on the engineered tissue formation mechanisms. This approach could open novel routes for the early detection of different degenerative conditions of tissue.
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20
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Cauble MA, Rothman E, Welch K, Fang M, Duong LT, Pennypacker BL, Orr BG, Banaszak Holl MM. Alteration of Type I collagen microstructure induced by estrogen depletion can be prevented with drug treatment. BONEKEY REPORTS 2015; 4:697. [PMID: 26131356 DOI: 10.1038/bonekey.2015.66] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 12/12/2014] [Indexed: 01/18/2023]
Abstract
Two independent biological replicates of estrogen depletion were employed with differing drug treatment conditions. Data Set I consisted of 9-month-old New Zealand white female rabbits treated as follows: sham-operated (n=11), ovariectomized (OVX; n=12), OVX+200 μg kg(-1) alendronate (ALN), 3 × a week for 27 weeks (n=12) and OVX+10 mg kg(-1) Cathepsin-K inhibitor (CatKI) daily for 27 weeks. Data Set II consisted of 6-month-old New Zealand white female rabbits that were sham-operated (n=12), OVX (n=12) or OVX+0.05 mg kg(-1) 17β-estradiol (ERT) 3 × a week for 13 weeks (n=12). Samples from the cortical femur were polished and demineralized to make them suitable for atomic force microscopy (AFM) imaging. Type I collagen fibrils present in bundles or sheets, running parallel to each other, were combined into a class termed Parallel. Fibrils present outside of such structures, typically in images with an angular range of non-parallel fibrils, were combined into a class termed Oblique. The percentage of fibrils coded as Parallel for Sham animals in Data Sets I and II was 52% and 53%, respectively. The percentage of fibrils coded as Parallel for OVX animals in Data Sets I and II was 35% in both cases. ALN and ERT drug treatments reduced the change from 18 to 12%, whereas CatKI treatment reduced the change to 5%.
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Affiliation(s)
- Meagan A Cauble
- Department of Chemistry, University of Michigan , Ann Arbor, MI, USA
| | - Edward Rothman
- Department of Statistics, University of Michigan , Ann Arbor, MI, USA ; Center for Statistical Consultation and Research (CSCAR), University of Michigan , Ann Arbor, MI, USA
| | - Kathleen Welch
- Center for Statistical Consultation and Research (CSCAR), University of Michigan , Ann Arbor, MI, USA
| | - Ming Fang
- Department of Chemistry, University of Michigan , Ann Arbor, MI, USA
| | - Le T Duong
- Bone Biology Group, Merck Research Laboratories , West Point, PA, USA
| | | | - Bradford G Orr
- Department of Physics, University of Michigan , Ann Arbor, MI, USA
| | - Mark M Banaszak Holl
- Department of Chemistry, University of Michigan , Ann Arbor, MI, USA ; Department of Biomedical Engineering, University of Michigan , Ann Arbor, MI, USA
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21
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Wallace JM. Effects of fixation and demineralization on bone collagen D-spacing as analyzed by atomic force microscopy. Connect Tissue Res 2015; 56:68-75. [PMID: 25634588 DOI: 10.3109/03008207.2015.1005209] [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] [Indexed: 02/03/2023]
Abstract
PURPOSE/AIM Collagen's role in bone is often considered secondary. As increased attention is paid to collagen, understanding the impact of tissue preservation is important in interpreting experimental results. The goal of this study was to test the hypothesis that bone fixation prior to demineralization would maintain its collagen ultrastructure in an undisturbed state when analyzed using Atomic Force Microscopy (AFM). MATERIALS/METHODS The anterior diaphysis of a pig femur was cut into 6 mm pieces along its length. Samples were mounted, polished and randomly assigned to control or fixation groups (n = 5/group). Fixation samples were fixed for 24 h prior to demineralization. All samples were briefly demineralized to expose collagen, and imaged using AFM. Mouse tail tendons were also analyzed to explore effects of dehydration and fixation. Measurements from each bone sample were averaged and compared using a Mann-Whitney U-test. Tendon sample means were compared using RMANOVA. To investigate differences in D-spacing distributions, Kolmogorov-Smirnov tests were used. RESULTS Fixation decreased D-spacing variability within and between bone samples and induced or maintained a higher average D-spacing versus control by shifting the D-spacing population upward. Tendon data indicate that fixing and drying samples leaves collagen near its undisturbed and hydrated native state. DISCUSSION Fixation in bone prior to demineralization decreased D-spacing variability. D-spacing was shifted upward in fixed samples, indicating that collagen is stretched with mineral present and relaxes upon its removal. The ability to decrease variability in bone suggests that fixation might increase the power to detect changes in collagen due to disease or other pressures.
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Affiliation(s)
- Joseph M Wallace
- Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis , Indianapolis, IN , USA and
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22
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Hammond MA, Wallace JM. Exercise prevents β-aminopropionitrile-induced morphological changes to type I collagen in murine bone. BONEKEY REPORTS 2015; 4:645. [PMID: 25798234 DOI: 10.1038/bonekey.2015.12] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 01/27/2015] [Indexed: 01/22/2023]
Abstract
This study evaluated the effects of reduced enzymatic crosslinking, exercise and the ability of exercise to prevent the deleterious impact of reduced crosslinking on collagen D-spacing. Eight-week-old female mice were divided into four weight-matched groups receiving daily injections of either phosphate-buffered saline (PBS) or 300 mg kg(-1) β-aminopropionitrile (BAPN) while undergoing normal cage activity (Sed) or 30 min per day of treadmill exercise (Ex) for 21 consecutive days. BAPN caused a downward shift in the D-spacing distribution in Sed BAPN compared with Sed PBS (P<0.001) but not in Ex BAPN (P=0.429), indicating that exercise can prevent changes in collagen morphology caused by BAPN. Exercise had no effect on D-spacing in PBS control mice (P=0.726), which suggests that exercise-induced increases in lysyl oxidase may be a possible mechanism for preventing BAPN-induced changes in D-spacing. The D-spacing changes were accompanied by an increase in mineral crystallinity/maturity due to the main effect of BAPN (P=0.016). However, no changes in nanoindentation, reference point indentation or other Raman spectroscopy parameters were observed. The ability of exercise to rescue BAPN-driven changes in collagen morphology necessitates further research into the use of mechanical stimulation as a preventative therapy for collagen-based diseases.
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Affiliation(s)
- Max A Hammond
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette , Indianapolis, IN, USA
| | - Joseph M Wallace
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette , Indianapolis, IN, USA ; Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis , Indianapolis, IN, USA ; Department of Orthopaedic Surgery, Indiana University School of Medicine , Indianapolis, IN, USA
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23
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Su HN, Ran LY, Chen ZH, Qin QL, Shi M, Song XY, Chen XL, Zhang YZ, Xie BB. The ultrastructure of type I collagen at nanoscale: large or small D-spacing distribution? NANOSCALE 2014; 6:8134-8139. [PMID: 24922185 DOI: 10.1039/c4nr01268b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
D-Spacing is the most significant topographic feature of type I collagen fibril, and it is important for our understanding of the structure and function in collagens. Traditionally, the D-spacing of type I collagen fibril was shown to have a singular value of 67 nm, but recent works indicated that the D-spacing values have a large distribution of up to 10 nm when measured by atomic force microscopy. We found that this large distribution of D-spacing values mainly resulted from image drift during measurement. Note that the D-spacing was homogeneous in a single type I collagen fibril. Our statistical analysis indicated that the D-spacing values of type I collagen fibrils exhibited only a narrow distribution of 2.5 nm around the value of 67 nm. In addition, the D-spacing values of the collagen fibrils were nearly identical not only within a single fibril bundle, but also in different fibril bundles. The measurement of the D-spacing values of collagen may provide important structural information in many research areas such as collagen related diseases, construction of molecular model of collagen, and collagen fibrogenesis.
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Affiliation(s)
- Hai-Nan Su
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China.
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Hammond MA, Gallant MA, Burr DB, Wallace JM. Nanoscale changes in collagen are reflected in physical and mechanical properties of bone at the microscale in diabetic rats. Bone 2014; 60:26-32. [PMID: 24269519 PMCID: PMC3944921 DOI: 10.1016/j.bone.2013.11.015] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 10/23/2013] [Accepted: 11/15/2013] [Indexed: 01/22/2023]
Abstract
Diabetes detrimentally affects the musculoskeletal system by stiffening the collagen matrix due to increased advanced glycation end products (AGEs). In this study, tibiae and tendon from Zucker diabetic Sprague-Dawley (ZDSD) rats were compared to Sprague-Dawley derived controls (CD) using Atomic Force Microscopy. ZDSD and CD tibiae were compared using Raman Spectroscopy and Reference Point Indentation (RPI). ZDSD bone had a significantly different distribution of collagen D-spacing than CD (p=0.015; ZDSD n=294 fibrils; CD n=274 fibrils) which was more variable and shifted to higher values. This shift between ZDSD and CD D-spacing distribution was more pronounced in tendon (p<0.001; ZDSD n=350; CD n=371). Raman revealed significant increases in measures of bone matrix mineralization in ZDSD (PO4(3-) ν1/Amide I p=0.008; PO4(3-) ν1/CH2 wag p=0.047; n=5 per group) despite lower bone mineral density (aBMD) and ash fraction indicating diabetes may preferentially reduce the Raman signature of collagen. Decreased indentation distance increase (p=0.010) and creep indentation distance (p=0.040) measured by RPI (n=9 per group) in ZDSD rats suggest a matrix more resistant to indentation under the high stresses associated with RPI at this length scale. There were significant correlations between Raman and RPI measurements in the ZDSD population (n=18 locations) but not the CD population (n=16 locations) indicating that while RPI is relatively unaffected by biological noise, it is sensitive to disease-induced compositional changes. In conclusion, diabetes in the ZDSD rat causes changes to the nanoscale morphology of collagen that result in compositional and mechanical effects in bone at the microscale.
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Affiliation(s)
- Max A Hammond
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Maxime A Gallant
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, IN, USA
| | - David B Burr
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, IN, USA; Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, IN, USA
| | - Joseph M Wallace
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA; Department of Orthopaedic Surgery, Indiana University School of Medicine, IN, USA; Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, IN, USA.
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Gonzalez AD, Gallant MA, Burr DB, Wallace JM. Multiscale analysis of morphology and mechanics in tail tendon from the ZDSD rat model of type 2 diabetes. J Biomech 2013; 47:681-6. [PMID: 24360194 DOI: 10.1016/j.jbiomech.2013.11.045] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 11/19/2013] [Accepted: 11/24/2013] [Indexed: 01/20/2023]
Abstract
Type 2 diabetes (T2D) impacts multiple organ systems including the circulatory, renal, nervous and musculoskeletal systems. In collagen-based tissues, one mechanism that may be responsible for detrimental mechanical impacts of T2D is the formation of advanced glycation end products (AGEs) leading to increased collagen stiffness and decreased toughness, resulting in brittle tissue behavior. The purpose of this study was to investigate tendon mechanical properties from normal and diabetic rats at two distinct length scales, testing the hypothesis that increased stiffness and strength and decreased toughness at the fiber level would be associated with alterations in nanoscale morphology and mechanics. Individual fascicles from female Zucker diabetic Sprague-Dawley (ZDSD) rats had no differences in fascicle-level mechanical properties but had increased material-level strength and stiffness versus control rats (CD). At the nanoscale, collagen fibril D-spacing was shifted towards higher spacing values in diabetic ZDSD fibrils. The distribution of nanoscale modulus values was also shifted to higher values. Material-level strength and stiffness from whole fiber tests were increased in ZDSD tails. Correlations between nanoscale and microscale properties indicate a direct positive relationship between the two length scales, most notably in the relationship between nanoscale and microscale modulus. These findings indicate that diabetes-induced changes in material strength and modulus were driven by alterations at the nanoscale.
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Affiliation(s)
- Armando Diaz Gonzalez
- Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, 723 W Michigan Street SL220D, Indianapolis, IN 46202, USA
| | - Maxime A Gallant
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - David B Burr
- Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, 723 W Michigan Street SL220D, Indianapolis, IN 46202, USA; Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Joseph M Wallace
- Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, 723 W Michigan Street SL220D, Indianapolis, IN 46202, USA; Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, USA.
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Fang M, Holl MMB. Variation in type I collagen fibril nanomorphology: the significance and origin. BONEKEY REPORTS 2013; 2:394. [PMID: 24422113 DOI: 10.1038/bonekey.2013.128] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 06/20/2013] [Accepted: 06/27/2013] [Indexed: 12/26/2022]
Abstract
Although the axial D-periodic spacing is a well-recognized nanomorphological feature of type I collagen fibrils, the existence of a distribution of values has been largely overlooked since its discovery seven decades ago. Studies based on single fibril measurements occasionally noted variation in D-spacing values, but accredited it with no biological significance. Recent quantitative characterizations supported that a 10-nm collagen D-spacing distribution is intrinsic to collagen fibrils in various tissues as well as in vitro self-assembly of reconstituted collagen. In addition, the distribution is altered in Osteogenesis Imperfecta and long-term estrogen deprivation. Bone collagen is organized into lamellar sheets of bundles at the micro-scale, and D-spacings within a bundle of a lamella are mostly identical, whereas variations among different bundles contribute to the full-scale distribution. This seems to be a very general phenomenon for the protein as the same type of D-spacing/bundle organization is observed for dermal and tendon collagen. More research investigation of collagen nanomorphology in connection to bone biology is required to fully understand these new observations. Here we review the data demonstrating the existence of a D-spacing distribution, the impact of disease on the distribution and possible explanations for the origin of D-spacing variations based on various collagen fibrillogenesis models.
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Affiliation(s)
- Ming Fang
- Department of Chemistry, University of Michigan , Ann Arbor, MI, USA
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27
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Fang M, Goldstein EL, Matich EK, Orr BG, Holl MMB. Type I collagen self-assembly: the roles of substrate and concentration. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:2330-2338. [PMID: 23339654 DOI: 10.1021/la3048104] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Collagen molecules, self-assembled into macroscopic hierarchical tissue networks, are the main organic building block of many biological tissues. A particularly common and important form of this self-assembly consists of type I collagen fibrils, which exhibit a nanoscopic signature, D-periodic gap/overlap spacing, with a distribution of values centered at approximately 67 nm. In order to better understand the relationship between type I collagen self-assembly and D-spacing distribution, we investigated surface-mediated collagen self-assembly as a function of substrate and incubation concentration. Collagen fibril assembly on phlogopite and muscovite mica as well as fibrillar gel coextrusion in glass capillary tubes all exhibited D-spacing distributions similar to those commonly observed in biological tissues. The observation of D-spacing distribution by self-assembly of type I collagen alone is significant as it eliminates the necessity to invoke other preassembly or postassembly hypotheses, such as variation in the content of collagen types, enzymatic cross-linking, or other post-translational modifications, as mechanistic origins of D-spacing distribution. The D-spacing distribution on phlogopite mica is independent of type I collagen concentration, but on muscovite mica D-spacing distributions showed increased negative skewness at 20 μg/mL and higher concentrations. Tilted D-spacing angles were found to correlate with decreased D-spacing measurements, an effect that can be removed with a tilt angle correction, resulting in no concentration dependence of D-spacing distribution on muscovite mica. We then demonstrated that tilted D-spacing is uncommon in biological tissues and it does not explain previous observations of low D-spacing values in ovariectomized dermis and bone.
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Affiliation(s)
- Ming Fang
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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28
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Kemp AD, Harding CC, Cabral WA, Marini JC, Wallace JM. Effects of tissue hydration on nanoscale structural morphology and mechanics of individual Type I collagen fibrils in the Brtl mouse model of Osteogenesis Imperfecta. J Struct Biol 2012; 180:428-38. [PMID: 23041293 PMCID: PMC3685442 DOI: 10.1016/j.jsb.2012.09.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 09/10/2012] [Accepted: 09/25/2012] [Indexed: 11/25/2022]
Abstract
Type I collagen is the most abundant protein in mammals, and is a vital part of the extracellular matrix for numerous tissues. Despite collagen's importance, little is known about its nanoscale morphology in tissues and how morphology relates to mechanical function. This study probes nanoscale structure and mechanical properties of collagen as a function of disease in native hydrated tendons. Wild type tendon and tendon from the Brtl/+ mouse model of Osteogenesis Imperfecta were investigated. An atomic force microscope (AFM) was used to image and indent minimally-processed collagen fibrils in hydrated and dehydrated conditions. AFM was used because of the ability to keep biological tissues as close to their native in situ conditions as possible. The study demonstrated phenotypic difference in Brtl/+ fibril morphology and mechanics in hydrated tendon which became more compelling upon dehydration. Dried tendons had a significant downward shift in fibril D-periodic spacing versus a shift up in wet tendons. Nanoscale changes in morphology in dry samples were accompanied by significant increases in modulus and adhesion force and decreased indentation depth. A minimal mechanical phenotype existed in hydrated samples, possibly due to water masking structural defects within the diseased fibrils. This study demonstrates that collagen nanoscale morphology and mechanics are impacted in Brtl/+ tendons, and that the phenotype can be modulated by the presence or absence of water. Dehydration causes artifacts in biological samples which require water and this factor must be considered for studies at any length scale in collagen-based tissues, especially when characterizing disease-induced differences.
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Affiliation(s)
- Arika D. Kemp
- Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, Indianapolis, IN, USA
| | - Chad C. Harding
- Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, Indianapolis, IN, USA
| | - Wayne A. Cabral
- Bone and Extracellular Matrix Branch, The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD, USA
| | - Joan C. Marini
- Bone and Extracellular Matrix Branch, The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD, USA
| | - Joseph M. Wallace
- Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, Indianapolis, IN, USA
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Fang M, Goldstein EL, Turner AS, Les CM, Orr BG, Fisher GJ, Welch KB, Rothman ED, Banaszak Holl MM. Type I collagen D-spacing in fibril bundles of dermis, tendon, and bone: bridging between nano- and micro-level tissue hierarchy. ACS NANO 2012; 6:9503-14. [PMID: 23083115 PMCID: PMC3508361 DOI: 10.1021/nn302483x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Fibrillar collagens in connective tissues are organized into complex and diverse hierarchical networks. In dermis, bone, and tendon, one common phenomenon at the micrometer scale is the organization of fibrils into bundles. Previously, we have reported that collagen fibrils in these tissues exhibit a 10 nm width distribution of D-spacing values. This study expands the observation to a higher hierarchical level by examining fibril D-spacing distribution in relation to the bundle organization. We used atomic force microscopy imaging and two-dimensional fast Fourier transform analysis to investigate dermis, tendon, and bone tissues. We found that, in each tissue type, collagen fibril D-spacings within a single bundle were nearly identical and frequently differ by less than 1 nm. The full 10 nm range in D-spacing values arises from different values found in different bundles. The similarity in D-spacing was observed to persist for up to 40 μm in bundle length and width. A nested mixed model analysis of variance examining 107 bundles and 1710 fibrils from dermis, tendon, and bone indicated that fibril D-spacing differences arise primarily at the bundle level (∼76%), independent of species or tissue types.
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Affiliation(s)
- Ming Fang
- Department of Chemistry, University of Michigan
- Michigan Nanotechnology Institute for Medicine and Biological Science, University of Michigan
| | | | | | - Clifford M. Les
- Center for Statistical Consultation and Research, University of Michigan
| | - Bradford G. Orr
- Michigan Nanotechnology Institute for Medicine and Biological Science, University of Michigan
- Department of Physics, University of Michigan
- Program in Applied Physics, University of Michigan
| | | | - Kathleen B. Welch
- Center for Statistical Consultation and Research, University of Michigan
| | - Edward D. Rothman
- Center for Statistical Consultation and Research, University of Michigan
- Department of Statistics, University of Michigan
| | - Mark M. Banaszak Holl
- Department of Chemistry, University of Michigan
- Michigan Nanotechnology Institute for Medicine and Biological Science, University of Michigan
- Program in Applied Physics, University of Michigan
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Erickson B, Fang M, Wallace JM, Orr BG, Les CM, Banaszak Holl MM. Nanoscale structure of type I collagen fibrils: quantitative measurement of D-spacing. Biotechnol J 2012; 8:117-26. [PMID: 23027700 DOI: 10.1002/biot.201200174] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 08/23/2012] [Accepted: 09/26/2012] [Indexed: 12/16/2022]
Abstract
This article details a quantitative method to measure the D-periodic spacing of type I collagen fibrils using atomic force microscopy coupled with analysis using a two-dimensional fast fourier transform approach. Instrument calibration, data sampling and data analysis are discussed and comparisons of the data to the complementary methods of electron microscopy and X-ray scattering are made. Examples of the application of this new approach to the analysis of type I collagen morphology in disease models of estrogen depletion and osteogenesis imperfecta (OI) are provided. We demonstrate that it is the D-spacing distribution, not the D-spacing mean, that showed statistically significant differences in estrogen depletion associated with early stage osteoporosis and OI. The ability to quantitatively characterize nanoscale morphological features of type I collagen fibrils will provide important structural information regarding type I collagen in many research areas, including tissue aging and disease, tissue engineering, and gene knockout studies. Furthermore, we also envision potential clinical applications including evaluation of tissue collagen integrity under the impact of diseases or drug treatments.
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Affiliation(s)
- Blake Erickson
- Program in Biophysics, University of Michigan, Ann Arbor, MI 48109-1055, USA
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