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Liu Z, Liu Y, Yu Z, Tan C, Pek N, O'Donnell A, Wu A, Glass I, Winlaw DS, Guo M, Spence JR, Chen YW, Yutzey KE, Miao Y, Gu M. APOE-NOTCH axis governs elastogenesis during human cardiac valve remodeling. NATURE CARDIOVASCULAR RESEARCH 2024; 3:933-950. [PMID: 39196035 DOI: 10.1038/s44161-024-00510-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 06/19/2024] [Indexed: 08/29/2024]
Abstract
Valve remodeling is a process involving extracellular matrix organization and elongation of valve leaflets. Here, through single-cell RNA sequencing of human fetal valves, we identified an elastin-producing valve interstitial cell (VIC) subtype (apolipoprotein E (APOE)+, elastin-VICs) spatially located underneath valve endothelial cells (VECs) sensing unidirectional flow. APOE knockdown in fetal VICs resulted in profound elastogenesis defects. In valves with pulmonary stenosis (PS), we observed elastin fragmentation and decreased expression of APOE along with other genes regulating elastogenesis. Cell-cell interaction analysis revealed that jagged 1 (JAG1) from unidirectional VECs activates elastogenesis in elastin-VICs through NOTCH2. Similar observations were made in VICs cocultured with VECs under unidirectional flow. Notably, a drastic reduction of JAG1-NOTCH2 was also observed in PS valves. Lastly, we found that APOE controls JAG1-induced NOTCH activation and elastogenesis in VICs through the extracellular signal-regulated kinase pathway. Our study suggests important roles of both APOE and NOTCH in regulating elastogenesis during human valve remodeling.
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Affiliation(s)
- Ziyi Liu
- Perinatal Institute, Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, OH, USA
| | - Yu Liu
- Cardiovascular Institute, Stanford School of Medicine, Stanford, CA, USA
- Division of Cardiovascular Medicine, Department of Medicine, Stanford School of Medicine, Stanford, CA, USA
| | - Zhiyun Yu
- Perinatal Institute, Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, OH, USA
| | - Cheng Tan
- Perinatal Institute, Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, OH, USA
| | - Nicole Pek
- Perinatal Institute, Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, OH, USA
| | - Anna O'Donnell
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, OH, USA
- The Heart Institute, Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Angeline Wu
- Department of Internal Medicine, Gastroenterology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Ian Glass
- Department of Pediatrics, Genetic Medicine, University of Washington, Seattle, WA, USA
| | - David S Winlaw
- Cardiothoracic Surgery, Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Surgery, University of Cincinnati School of Medicine, Cincinnati, OH, USA
| | - Minzhe Guo
- Perinatal Institute, Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, OH, USA
| | - Jason R Spence
- Department of Internal Medicine, Gastroenterology, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Biomedical Engineering, University of Michigan College of Engineering, Ann Arbor, MI, USA
| | - Ya-Wen Chen
- Department of Cell, Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Otolaryngology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Institute for Airway Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Katherine E Yutzey
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, OH, USA
- The Heart Institute, Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Yifei Miao
- Perinatal Institute, Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, OH, USA.
- Cardiovascular Institute, Stanford School of Medicine, Stanford, CA, USA.
- Division of Pediatric Cardiology, Department of Pediatrics, Stanford School of Medicine, Stanford, CA, USA.
| | - Mingxia Gu
- Perinatal Institute, Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, OH, USA.
- Cardiovascular Institute, Stanford School of Medicine, Stanford, CA, USA.
- Division of Pediatric Cardiology, Department of Pediatrics, Stanford School of Medicine, Stanford, CA, USA.
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Conci C, Sironi L, Jacchetti E, Panzeri D, Inverso D, Martínez Vázquez R, Osellame R, Collini M, Cerullo G, Chirico G, Raimondi MT. In vivo label-free tissue histology through a microstructured imaging window. APL Bioeng 2024; 8:016102. [PMID: 38222895 PMCID: PMC10787586 DOI: 10.1063/5.0165411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 11/06/2023] [Indexed: 01/16/2024] Open
Abstract
Tissue histopathology, based on hematoxylin and eosin (H&E) staining of thin tissue slices, is the gold standard for the evaluation of the immune reaction to the implant of a biomaterial. It is based on lengthy and costly procedures that do not allow longitudinal studies. The use of non-linear excitation microscopy in vivo, largely label-free, has the potential to overcome these limitations. With this purpose, we develop and validate an implantable microstructured device for the non-linear excitation microscopy assessment of the immune reaction to an implanted biomaterial label-free. The microstructured device, shaped as a matrix of regular 3D lattices, is obtained by two-photon laser polymerization. It is subsequently implanted in the chorioallantoic membrane (CAM) of embryonated chicken eggs for 7 days to act as an intrinsic 3D reference frame for cell counting and identification. The histological analysis based on H&E images of the tissue sections sampled around the implanted microstructures is compared to non-linear excitation and confocal images to build a cell atlas that correlates the histological observations to the label-free images. In this way, we can quantify the number of cells recruited in the tissue reconstituted in the microstructures and identify granulocytes on label-free images within and outside the microstructures. Collagen and microvessels are also identified by means of second-harmonic generation and autofluorescence imaging. The analysis indicates that the tissue reaction to implanted microstructures is like the one typical of CAM healing after injury, without a massive foreign body reaction. This opens the path to the use of similar microstructures coupled to a biomaterial, to image in vivo the regenerating interface between a tissue and a biomaterial with label-free non-linear excitation microscopy. This promises to be a transformative approach, alternative to conventional histopathology, for the bioengineering and the validation of biomaterials in in vivo longitudinal studies.
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Affiliation(s)
- Claudio Conci
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta,” Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Laura Sironi
- Department of Physics, Università di Milano-Bicocca, Piazza della Scienza 3, 20126 Milan, Italy
| | - Emanuela Jacchetti
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta,” Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Davide Panzeri
- Department of Physics, Università di Milano-Bicocca, Piazza della Scienza 3, 20126 Milan, Italy
| | - Donato Inverso
- Division of Immunology, Transplantation and Infectious Diseases IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Rebeca Martínez Vázquez
- Institute for Photonics and Nanotechnologies (IFN), CNR and Department of Physics, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Roberto Osellame
- Institute for Photonics and Nanotechnologies (IFN), CNR and Department of Physics, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Maddalena Collini
- Department of Physics, Università di Milano-Bicocca, Piazza della Scienza 3, 20126 Milan, Italy
| | - Giulio Cerullo
- Institute for Photonics and Nanotechnologies (IFN), CNR and Department of Physics, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
| | - Giuseppe Chirico
- Department of Physics, Università di Milano-Bicocca, Piazza della Scienza 3, 20126 Milan, Italy
| | - Manuela Teresa Raimondi
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta,” Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy
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3
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Alser M, Salman HE, Naïja A, Seers TD, Khan T, Yalcin HC. Blood Flow Disturbance and Morphological Alterations Following the Right Atrial Ligation in the Chick Embryo. Front Physiol 2022; 13:849603. [PMID: 35492580 PMCID: PMC9047544 DOI: 10.3389/fphys.2022.849603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 02/28/2022] [Indexed: 11/23/2022] Open
Abstract
Collectively known as congenital heart defects (CHDs), cardiac abnormalities at birth are the most common forms of neonatal defects. Being principally responsible for the heart‘s pumping power, ventricles are particularly affected by developmental abnormalities, such as flow disturbances or genomic defects. Hypoplastic Right Heart Syndrome (HRHS) is a rare disease where the right ventricle is underdeveloped. In this study, we introduce a surgical procedure performed on chick embryo, termed right atrial ligation (RAL) for disturbing hemodynamics within the right heart aiming in order to generate an animal model of HRHS. RAL is a new surgical manipulation, similar to the well-studied left atrial ligation (LAL) surgery but it induces the hemodynamic change into the right side of the heart. After inducing RAL, We utilized techniques such as Doppler ultrasound, x-ray micro-CT, histology, and computational fluid dynamics (CFD) analysis, for a comprehensive functional and structural analysis of a developing heart. Our results displayed that RAL does not induce severe flow disturbance and ventricular abnormalities consistent with clinical findings. This study allows us to better understand the hemodynamics-driven CHD development and sensitivities of ventricles under disturbed flows.
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Affiliation(s)
- Maha Alser
- Biomedical Research Center, Qatar University, Doha, Qatar
| | - Huseyin Enes Salman
- Department of Mechanical Engineering, TOBB University of Economics and Technology, Ankara, Turkey
| | - Azza Naïja
- Biomedical Research Center, Qatar University, Doha, Qatar
| | | | - Talha Khan
- Petroleum Engineering Program, Texas A&M University, Doha, Qatar
| | - Huseyin Cagatay Yalcin
- Biomedical Research Center, Qatar University, Doha, Qatar
- *Correspondence: Huseyin Cagatay Yalcin,
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4
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Bouzin M, Zeynali A, Marini M, Sironi L, Scodellaro R, D’Alfonso L, Collini M, Chirico G. Multiphoton Laser Fabrication of Hybrid Photo-Activable Biomaterials. SENSORS 2021; 21:s21175891. [PMID: 34502787 PMCID: PMC8433654 DOI: 10.3390/s21175891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 08/27/2021] [Accepted: 08/27/2021] [Indexed: 11/16/2022]
Abstract
The possibility to shape stimulus-responsive optical polymers, especially hydrogels, by means of laser 3D printing and ablation is fostering a new concept of “smart” micro-devices that can be used for imaging, thermal stimulation, energy transducing and sensing. The composition of these polymeric blends is an essential parameter to tune their properties as actuators and/or sensing platforms and to determine the elasto-mechanical characteristics of the printed hydrogel. In light of the increasing demand for micro-devices for nanomedicine and personalized medicine, interest is growing in the combination of composite and hybrid photo-responsive materials and digital micro-/nano-manufacturing. Existing works have exploited multiphoton laser photo-polymerization to obtain fine 3D microstructures in hydrogels in an additive manufacturing approach or exploited laser ablation of preformed hydrogels to carve 3D cavities. Less often, the two approaches have been combined and active nanomaterials have been embedded in the microstructures. The aim of this review is to give a short overview of the most recent and prominent results in the field of multiphoton laser direct writing of biocompatible hydrogels that embed active nanomaterials not interfering with the writing process and endowing the biocompatible microstructures with physically or chemically activable features such as photothermal activity, chemical swelling and chemical sensing.
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Affiliation(s)
- Margaux Bouzin
- Dipartimento di Fisica, Università degli studi di Milano-Bicocca, 20126 Milano, Italy; (M.B.); (A.Z.); (M.M.); (L.S.); (R.S.); (L.D.)
| | - Amirbahador Zeynali
- Dipartimento di Fisica, Università degli studi di Milano-Bicocca, 20126 Milano, Italy; (M.B.); (A.Z.); (M.M.); (L.S.); (R.S.); (L.D.)
| | - Mario Marini
- Dipartimento di Fisica, Università degli studi di Milano-Bicocca, 20126 Milano, Italy; (M.B.); (A.Z.); (M.M.); (L.S.); (R.S.); (L.D.)
| | - Laura Sironi
- Dipartimento di Fisica, Università degli studi di Milano-Bicocca, 20126 Milano, Italy; (M.B.); (A.Z.); (M.M.); (L.S.); (R.S.); (L.D.)
| | - Riccardo Scodellaro
- Dipartimento di Fisica, Università degli studi di Milano-Bicocca, 20126 Milano, Italy; (M.B.); (A.Z.); (M.M.); (L.S.); (R.S.); (L.D.)
| | - Laura D’Alfonso
- Dipartimento di Fisica, Università degli studi di Milano-Bicocca, 20126 Milano, Italy; (M.B.); (A.Z.); (M.M.); (L.S.); (R.S.); (L.D.)
| | - Maddalena Collini
- Dipartimento di Fisica, Università degli studi di Milano-Bicocca, 20126 Milano, Italy; (M.B.); (A.Z.); (M.M.); (L.S.); (R.S.); (L.D.)
- Institute for Applied Sciences and Intelligent Systems, CNR, 80078 Pozzuoli, Italy
- Correspondence: (M.C.); (G.C.)
| | - Giuseppe Chirico
- Dipartimento di Fisica, Università degli studi di Milano-Bicocca, 20126 Milano, Italy; (M.B.); (A.Z.); (M.M.); (L.S.); (R.S.); (L.D.)
- Institute for Applied Sciences and Intelligent Systems, CNR, 80078 Pozzuoli, Italy
- Correspondence: (M.C.); (G.C.)
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5
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Computational Modeling of Blood Flow Hemodynamics for Biomechanical Investigation of Cardiac Development and Disease. J Cardiovasc Dev Dis 2021; 8:jcdd8020014. [PMID: 33572675 PMCID: PMC7912127 DOI: 10.3390/jcdd8020014] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 01/16/2021] [Accepted: 01/21/2021] [Indexed: 12/11/2022] Open
Abstract
The heart is the first functional organ in a developing embryo. Cardiac development continues throughout developmental stages while the heart goes through a serious of drastic morphological changes. Previous animal experiments as well as clinical observations showed that disturbed hemodynamics interfere with the development of the heart and leads to the formation of a variety of defects in heart valves, heart chambers, and blood vessels, suggesting that hemodynamics is a governing factor for cardiogenesis, and disturbed hemodynamics is an important source of congenital heart defects. Therefore, there is an interest to image and quantify the flowing blood through a developing heart. Flow measurement in embryonic fetal heart can be performed using advanced techniques such as magnetic resonance imaging (MRI) or echocardiography. Computational fluid dynamics (CFD) modeling is another approach especially useful when the other imaging modalities are not available and in-depth flow assessment is needed. The approach is based on numerically solving relevant physical equations to approximate the flow hemodynamics and tissue behavior. This approach is becoming widely adapted to simulate cardiac flows during the embryonic development. While there are few studies for human fetal cardiac flows, many groups used zebrafish and chicken embryos as useful models for elucidating normal and diseased cardiogenesis. In this paper, we explain the major steps to generate CFD models for simulating cardiac hemodynamics in vivo and summarize the latest findings on chicken and zebrafish embryos as well as human fetal hearts.
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6
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Salman HE, Alser M, Shekhar A, Gould RA, Benslimane FM, Butcher JT, Yalcin HC. Effect of left atrial ligation-driven altered inflow hemodynamics on embryonic heart development: clues for prenatal progression of hypoplastic left heart syndrome. Biomech Model Mechanobiol 2021; 20:733-750. [PMID: 33481120 PMCID: PMC7979615 DOI: 10.1007/s10237-020-01413-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 12/14/2020] [Indexed: 12/18/2022]
Abstract
Congenital heart defects (CHDs) are abnormalities in the heart structure present at birth. One important condition is hypoplastic left heart syndrome (HLHS) where severely underdeveloped left ventricle (LV) cannot support systemic circulation. HLHS usually initiates as localized tissue malformations with no underlying genetic cause, suggesting that disturbed hemodynamics contribute to the embryonic development of these defects. Left atrial ligation (LAL) is a surgical procedure on embryonic chick resulting in a phenotype resembling clinical HLHS. In this study, we investigated disturbed hemodynamics and deteriorated cardiac growth following LAL to investigate possible mechanobiological mechanisms for the embryonic development of HLHS. We integrated techniques such as echocardiography, micro-CT and computational fluid dynamics (CFD) for these analyses. Specifically, LAL procedure causes an immediate flow disturbance over atrioventricular (AV) cushions. At later stages after the heart septation, it causes hemodynamic disturbances in LV. As a consequence of the LAL procedure, the left-AV canal and LV volume decrease in size, and in the opposite way, the right-AV canal and right ventricle volume increase. According to our CFD analysis, LAL results in an immediate decrease in the left AV canal WSS levels for 3.5-day (HH21) pre-septated hearts. For 7-day post-septated hearts (HH30), LAL leads to further reduction in WSS levels in the left AV canal, and relatively increased WSS levels in the right AV canal. This study demonstrates the critical importance of the disturbed hemodynamics during the heart valve and ventricle development.
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Affiliation(s)
- Huseyin Enes Salman
- Biomedical Research Center, Qatar University, Doha, Qatar
- Department of Mechanical Engineering, TOBB University of Economics and Technology, Ankara, Turkey
| | - Maha Alser
- Biomedical Research Center, Qatar University, Doha, Qatar
| | - Akshay Shekhar
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, USA
- Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | - Russell A Gould
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | | | - Jonathan T Butcher
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, USA
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7
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Advanced blood flow assessment in Zebrafish via experimental digital particle image velocimetry and computational fluid dynamics modeling. Micron 2020; 130:102801. [DOI: 10.1016/j.micron.2019.102801] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/18/2019] [Accepted: 12/13/2019] [Indexed: 01/23/2023]
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8
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Lindsey SE, Butcher JT, Vignon-Clementel IE. Cohort-based multiscale analysis of hemodynamic-driven growth and remodeling of the embryonic pharyngeal arch arteries. Development 2018; 145:145/20/dev162578. [PMID: 30333235 DOI: 10.1242/dev.162578] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 08/31/2018] [Indexed: 01/16/2023]
Abstract
Growth and remodeling of the primitive pharyngeal arch artery (PAA) network into the extracardiac great vessels is poorly understood but a major source of clinically serious malformations. Undisrupted blood flow is required for normal PAA development, yet specific relationships between hemodynamics and remodeling remain largely unknown. Meeting this challenge is hindered by the common reductionist analysis of morphology to single idealized models, where in fact structural morphology varies substantially. Quantitative technical tools that allow tracking of morphological and hemodynamic changes in a population-based setting are essential to advancing our understanding of morphogenesis. Here, we have developed a methodological pipeline from high-resolution nano-computed tomography imaging and live-imaging flow measurements to multiscale pulsatile computational models. We combine experimental-based computational models of multiple PAAs to quantify hemodynamic forces in the rapidly morphing Hamburger Hamilton (HH) stage HH18, HH24 and HH26 embryos. We identify local morphological variation along the PAAs and their association with specific hemodynamic changes. Population-level mechano-morphogenic variability analysis is a powerful strategy for identifying stage-specific regions of well and poorly tolerated morphological and/or hemodynamic variation that may protect or initiate cardiovascular malformations.
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Affiliation(s)
- Stephanie E Lindsey
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Ithaca, NY 14850, USA
| | - Jonathan T Butcher
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Ithaca, NY 14850, USA
| | - Irene E Vignon-Clementel
- INRIA Centre de recherche de Paris, Paris 75012, France .,Laboratoire Jacques Louis Lions, Sorbonne Universités UPMC, Paris 75005, France
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Hoog TG, Fredrickson SJ, Hsu CW, Senger SM, Dickinson ME, Udan RS. The effects of reduced hemodynamic loading on morphogenesis of the mouse embryonic heart. Dev Biol 2018; 442:127-137. [PMID: 30012423 DOI: 10.1016/j.ydbio.2018.07.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/09/2018] [Accepted: 07/10/2018] [Indexed: 12/20/2022]
Abstract
Development of the embryonic heart involves an intricate network of biochemical and genetic cues to ensure its proper growth and morphogenesis. However, studies from avian and teleost models reveal that biomechanical force, namely hemodynamic loading (blood pressure and shear stress), plays a significant role in regulating heart development. To study how hemodynamic loading impacts development of the mammalian embryonic heart, we utilized mouse embryo culture and manipulation techniques and performed optical projection tomography imaging followed by morphometric analysis to determine how reduced-loading affects heart volume, myocardial thickness, trabeculation and looping. Our results reveal that hemodynamic loading can regulate these features at different thresholds. Intermediate levels of hemodynamic loading are sufficient to promote proper myocardial growth and heart size, but insufficient to promote looping and trabeculation. Whereas, low levels of hemodynamic loading fails to promote proper growth of the myocardium and heart size. These results reveal that the regulation of heart development by biomechanical force is conserved across many vertebrate classes, and this study begins to elucidate how these specific forces regulate development of the mammalian heart.
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Affiliation(s)
- Tanner G Hoog
- Department of Biology, Missouri State University, United States
| | | | - Chih-Wei Hsu
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, United States
| | - Steven M Senger
- Department of Mathematics, Missouri State University, United States
| | - Mary E Dickinson
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, United States
| | - Ryan S Udan
- Department of Biology, Missouri State University, United States.
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10
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Pradhan S, Keller KA, Sperduto JL, Slater JH. Fundamentals of Laser-Based Hydrogel Degradation and Applications in Cell and Tissue Engineering. Adv Healthc Mater 2017; 6:10.1002/adhm.201700681. [PMID: 29065249 PMCID: PMC5797692 DOI: 10.1002/adhm.201700681] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 08/13/2017] [Indexed: 12/24/2022]
Abstract
The cell and tissue engineering fields have profited immensely through the implementation of highly structured biomaterials. The development and implementation of advanced biofabrication techniques have established new avenues for generating biomimetic scaffolds for a multitude of cell and tissue engineering applications. Among these, laser-based degradation of biomaterials is implemented to achieve user-directed features and functionalities within biomimetic scaffolds. This review offers an overview of the physical mechanisms that govern laser-material interactions and specifically, laser-hydrogel interactions. The influences of both laser and material properties on efficient, high-resolution hydrogel degradation are discussed and the current application space in cell and tissue engineering is reviewed. This review aims to acquaint readers with the capability and uses of laser-based degradation of biomaterials, so that it may be easily and widely adopted.
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Affiliation(s)
- Shantanu Pradhan
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark DE 19716, USA
| | - Keely A. Keller
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark DE 19716, USA
| | - John L. Sperduto
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark DE 19716, USA
| | - John H. Slater
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark DE 19716, USA
- Delaware Biotechnology Institute, 15 Innovation Way, Newark, DE 19711, USA
- Department of Materials Science and Engineering, University of Delaware, 201 DuPont Hall, Newark, DE 19716, USA
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11
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Goddard LM, Duchemin AL, Ramalingan H, Wu B, Chen M, Bamezai S, Yang J, Li L, Morley MP, Wang T, Scherrer-Crosbie M, Frank DB, Engleka KA, Jameson SC, Morrisey EE, Carroll TJ, Zhou B, Vermot J, Kahn ML. Hemodynamic Forces Sculpt Developing Heart Valves through a KLF2-WNT9B Paracrine Signaling Axis. Dev Cell 2017; 43:274-289.e5. [PMID: 29056552 DOI: 10.1016/j.devcel.2017.09.023] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Revised: 08/01/2017] [Accepted: 09/25/2017] [Indexed: 01/08/2023]
Abstract
Hemodynamic forces play an essential epigenetic role in heart valve development, but how they do so is not known. Here, we show that the shear-responsive transcription factor KLF2 is required in endocardial cells to regulate the mesenchymal cell responses that remodel cardiac cushions to mature valves. Endocardial Klf2 deficiency results in defective valve formation associated with loss of Wnt9b expression and reduced canonical WNT signaling in neighboring mesenchymal cells, a phenotype reproduced by endocardial-specific loss of Wnt9b. Studies in zebrafish embryos reveal that wnt9b expression is similarly restricted to the endocardial cells overlying the developing heart valves and is dependent upon both hemodynamic shear forces and klf2a expression. These studies identify KLF2-WNT9B signaling as a conserved molecular mechanism by which fluid forces sensed by endothelial cells direct the complex cellular process of heart valve development and suggest that congenital valve defects may arise due to subtle defects in this mechanotransduction pathway.
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Affiliation(s)
- Lauren M Goddard
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Anne-Laure Duchemin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch 67404, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch 67404, France; Institut National de la Santé et de la Recherche Médicale, U964, Illkirch 67404, France; Université de Strasbourg, Illkirch 67404, France
| | - Harini Ramalingan
- Department of Internal Medicine (Nephrology) and Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Bingruo Wu
- Department of Genetics, Pediatric, and Medicine (Cardiology) and Wilf Cardiovascular Research Institute, Albert Einstein College of Medicine of Yeshiva University, 1301 Morris Park Avenue, Bronx, NY 10461, USA
| | - Mei Chen
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Sharika Bamezai
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Jisheng Yang
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Li Li
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Michael P Morley
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Tao Wang
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Marielle Scherrer-Crosbie
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - David B Frank
- Division of Pediatric Cardiology, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Kurt A Engleka
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Stephen C Jameson
- Department of Laboratory Medicine and Pathology, Center for Immunology, University of Minnesota, Minneapolis, MN, USA
| | - Edward E Morrisey
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Thomas J Carroll
- Department of Internal Medicine (Nephrology) and Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Bin Zhou
- Department of Genetics, Pediatric, and Medicine (Cardiology) and Wilf Cardiovascular Research Institute, Albert Einstein College of Medicine of Yeshiva University, 1301 Morris Park Avenue, Bronx, NY 10461, USA
| | - Julien Vermot
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch 67404, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch 67404, France; Institut National de la Santé et de la Recherche Médicale, U964, Illkirch 67404, France; Université de Strasbourg, Illkirch 67404, France
| | - Mark L Kahn
- Department of Medicine and Cardiovascular Institute, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA 19104, USA.
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12
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Yalcin HC, Amindari A, Butcher JT, Althani A, Yacoub M. Heart function and hemodynamic analysis for zebrafish embryos. Dev Dyn 2017; 246:868-880. [PMID: 28249360 DOI: 10.1002/dvdy.24497] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 02/24/2017] [Accepted: 02/24/2017] [Indexed: 12/28/2022] Open
Abstract
The Zebrafish has emerged to become a powerful vertebrate animal model for cardiovascular research in recent years. Its advantages include easy genetic manipulation, transparency, small size, low cost, and the ability to survive without active circulation at early stages of development. Sequencing the whole genome and identifying ortholog genes with human genome made it possible to induce clinically relevant cardiovascular defects via genetic approaches. Heart function and disturbed hemodynamics need to be assessed in a reliable manner for these disease models in order to reveal the mechanobiology of induced defects. This effort requires precise determination of blood flow patterns as well as hemodynamic stress (i.e., wall shear stress and pressure) levels within the developing heart. While traditional approach involves time-lapse brightfield microscopy to track cell and tissue movements, in more recent studies fast light-sheet fluorescent microscopes are utilized for that purpose. Integration of more complicated techniques like particle image velocimetry and computational fluid dynamics modeling for hemodynamic analysis holds a great promise to the advancement of the Zebrafish studies. Here, we discuss the latest developments in heart function and hemodynamic analysis for Zebrafish embryos and conclude with our future perspective on dynamic analysis of the Zebrafish cardiovascular system. Developmental Dynamics 246:868-880, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
| | - Armin Amindari
- Faculty of Mechanical Engineering, Istanbul Technical University, Istanbul, Turkey
| | - Jonathan T Butcher
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, United States
| | - Asma Althani
- Biomedical Research Center, Qatar University, Doha, Qatar
| | - Magdi Yacoub
- Imperial College, NHLI, Heart Science Centre, Harefield, Middlesex, UB9 6JH, United Kingdom
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13
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Men J, Jerwick J, Wu P, Chen M, Alex A, Ma Y, Tanzi RE, Li A, Zhou C. Drosophila Preparation and Longitudinal Imaging of Heart Function In Vivo Using Optical Coherence Microscopy (OCM). J Vis Exp 2016. [PMID: 28060288 DOI: 10.3791/55002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Longitudinal study of the heartbeat in small animals contributes to understanding structural and functional changes during heart development. Optical coherence microscopy (OCM) has been demonstrated to be capable of imaging small animal hearts with high spatial resolution and ultrahigh imaging speed. The high image contrast and noninvasive properties make OCM ideal for performing longitudinal studies without requiring tissue dissections or staining. Drosophila has been widely used as a model organism in cardiac developmental studies due to its high number of orthologous human disease genes, its similarity of molecular mechanisms and genetic pathways with vertebrates, its short life cycle, and its low culture cost. Here, the experimental protocols are described for the preparation of Drosophila and optical imaging of the heartbeat with a custom OCM system throughout the life cycle of the specimen. By following the steps provided in this report, transverse M-mode and 3D OCM images can be acquired to conduct longitudinal studies of the Drosophila cardiac morphology and function. The en face and axial sectional OCM images and the heart rate (HR) and cardiac activity period (CAP) histograms, were also shown to analyze the heart structural changes and to quantify the heart dynamics during Drosophila metamorphosis, combined with the videos constructed with M-mode images to trace cardiac activity intuitively. Due to the genetic similarity between Drosophila and vertebrates, longitudinal study of heart morphology and dynamics in fruit flies could help reveal the origins of human heart diseases. The protocol here would provide an effective method to perform a wide range of studies to understand the mechanisms of cardiac diseases in humans.
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Affiliation(s)
- Jing Men
- Bioengineering Program, Lehigh University; Center for Photonics and Nanoelectronics, Lehigh University
| | - Jason Jerwick
- Center for Photonics and Nanoelectronics, Lehigh University; Department of Electrical and Computer Engineering, Lehigh University
| | - Penghe Wu
- Bioengineering Program, Lehigh University; Center for Photonics and Nanoelectronics, Lehigh University
| | - Mingming Chen
- Department of Electrical and Computer Engineering, Lehigh University; State Key Laboratory of Software Engineering, Wuhan University
| | - Aneesh Alex
- Center for Photonics and Nanoelectronics, Lehigh University; Department of Electrical and Computer Engineering, Lehigh University
| | - Yutao Ma
- State Key Laboratory of Software Engineering, Wuhan University
| | - Rudolph E Tanzi
- Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School
| | - Airong Li
- Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School
| | - Chao Zhou
- Bioengineering Program, Lehigh University; Center for Photonics and Nanoelectronics, Lehigh University; Department of Electrical and Computer Engineering, Lehigh University;
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14
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Lindsey SE, Menon PG, Kowalski WJ, Shekhar A, Yalcin HC, Nishimura N, Schaffer CB, Butcher JT, Pekkan K. Growth and hemodynamics after early embryonic aortic arch occlusion. Biomech Model Mechanobiol 2015; 14:735-51. [PMID: 25416845 PMCID: PMC4452432 DOI: 10.1007/s10237-014-0633-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 11/05/2014] [Indexed: 01/28/2023]
Abstract
The majority of severe clinically significant forms of congenital heart disease (CHD) are associated with great artery lesions, including hypoplastic, double, right or interrupted aortic arch morphologies. While fetal and neonatal interventions are advancing, their potential ability to restore cardiac function, optimal timing, location, and intensity required for intervention remain largely unknown. Here, we combine computational fluid dynamics (CFD) simulations with in vivo experiments to test how individual pharyngeal arch artery hemodynamics alter as a result of local interventions obstructing individual arch artery flow. Simulated isolated occlusions within each pharyngeal arch artery were created with image-derived three-dimensional (3D) reconstructions of normal chick pharyngeal arch anatomy at Hamburger-Hamilton (HH) developmental stages HH18 and HH24. Acute flow redistributions were then computed using in vivo measured subject-specific aortic sinus inflow velocity profiles. A kinematic vascular growth-rendering algorithm was then developed and implemented to test the role of changing local wall shear stress patterns in downstream 3D morphogenesis of arch arteries. CFD simulations predicted that altered pressure gradients and flow redistributions were most sensitive to occlusion of the IVth arches. To evaluate these simulations experimentally, a novel in vivo experimental model of pharyngeal arch occlusion was developed and implemented using two-photon microscopy-guided femtosecond laser-based photodisruption surgery. The right IVth arch was occluded at HH18, and resulting diameter changes were followed for up to 24 h. Pharyngeal arch diameter responses to acute hemodynamic changes were predicted qualitatively but poorly quantitatively. Chronic growth and adaptation to hemodynamic changes, however, were predicted in a subset of arches. Our findings suggest that this complex biodynamic process is governed through more complex forms of mechanobiological vascular growth rules. Other factors in addition to wall shear stress or more complex WSS rules are likely important in the long-term arterial growth and patterning. Combination in silico/experimental platforms are essential for accelerating our understanding and prediction of consequences from embryonic/fetal cardiovascular occlusions and lay the foundation for noninvasive methods to guide CHD diagnosis and fetal intervention.
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Affiliation(s)
| | - Prahlad G. Menon
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA
| | - William J. Kowalski
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA
| | - Akshay Shekhar
- Department of Biomedical Engineering, Cornell University, Ithaca, NY
| | - Huseyin C. Yalcin
- Department of Mechanical Engineering, Dogus University, Istanbul, Turkey
| | - Nozomi Nishimura
- Department of Biomedical Engineering, Cornell University, Ithaca, NY
| | - Chris B. Schaffer
- Department of Biomedical Engineering, Cornell University, Ithaca, NY
| | | | - Kerem Pekkan
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA
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15
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Yalcin HC. Femtosecond laser photodisruption of vitelline vessels of avian embryos as a technique to study embryonic vascular remodeling. Exp Biol Med (Maywood) 2014; 239:1644-52. [DOI: 10.1177/1535370214546272] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
During cardiogenesis, congenital heart defects (CHDs), generally start as local tissue abnormalities without underlying genetic causes, suggesting abnormal hemodynamics may be an important source. Due to the scarcity of experimental techniques that permits the formation of minimally-invasive and well-controlled cardiac perturbations, experimental investigation of embryonic development of CHD via in-vivo models is difficult. In this study, in order to investigate the relationship between abnormal mechanical signaling and embryonic CHD development, a previously developed laser-based technique was adopted to alter chicken embryonic cardiovascular development. The technique incorporates two-photon fluorescence microscopy to visualize deep tissue while femtosecond-pulsed laser photodisruption is used to ablate targeted tissue. Vitelline vessel remodeling under abnormal hemodynamics was the prime concern of the study. In order to alter the hemodynamics, blood flowing inside 50–300 µm diameter Hamburger–Hamilton 24 embryonic vessels was selectively ablated. Red blood cells in the blood and endothelial cells of the vessel walls were damaged as a result of ablation. Cellular injuries led to micro-occlusions in the vessels. Several micro-occlusions formed stable clots, resulting in a complete cessation of blood flow in the targeted vessels. By measuring blood velocities in the surrounding vessels via line scanning technique, the subsequent redistribution of blood flow in the immediate upstream and downstream vessels was revealed. The network was analyzed after 24 h, and it was found to be degraded. Degradation of the entire network can be attributed to the abnormalities in hemodynamics within the vessels. For studying embryonic development of heart defects under disturbed flow conditions, the present study can be extended to clot a blood vessel inside the embryo or a vitelline vessel in the vicinity of the heart. These results demonstrate that, laser-based noninvasive tools should be considered as powerful techniques to analyze hemodynamic signals encountered in embryonic development of CHD.
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Affiliation(s)
- Huseyin C Yalcin
- Mechanical Engineering Department, Dogus University, Kadikoy, 34722 İstanbul, Turkey
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16
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Lindsey SE, Butcher JT, Yalcin HC. Mechanical regulation of cardiac development. Front Physiol 2014; 5:318. [PMID: 25191277 DOI: 10.3389/fphys.2014.00318/bibtex] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 08/03/2014] [Indexed: 05/25/2023] Open
Abstract
Mechanical forces are essential contributors to and unavoidable components of cardiac formation, both inducing and orchestrating local and global molecular and cellular changes. Experimental animal studies have contributed substantially to understanding the mechanobiology of heart development. More recent integration of high-resolution imaging modalities with computational modeling has greatly improved our quantitative understanding of hemodynamic flow in heart development. Merging these latest experimental technologies with molecular and genetic signaling analysis will accelerate our understanding of the relationships integrating mechanical and biological signaling for proper cardiac formation. These advances will likely be essential for clinically translatable guidance for targeted interventions to rescue malforming hearts and/or reconfigure malformed circulations for optimal performance. This review summarizes our current understanding on the levels of mechanical signaling in the heart and their roles in orchestrating cardiac development.
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Affiliation(s)
| | - Jonathan T Butcher
- Department of Biomedical Engineering, Cornell University Ithaca, NY, USA
| | - Huseyin C Yalcin
- Department of Mechanical Engineering, Dogus University Istanbul, Turkey
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17
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Lindsey SE, Butcher JT, Yalcin HC. Mechanical regulation of cardiac development. Front Physiol 2014; 5:318. [PMID: 25191277 PMCID: PMC4140306 DOI: 10.3389/fphys.2014.00318] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 08/03/2014] [Indexed: 12/21/2022] Open
Abstract
Mechanical forces are essential contributors to and unavoidable components of cardiac formation, both inducing and orchestrating local and global molecular and cellular changes. Experimental animal studies have contributed substantially to understanding the mechanobiology of heart development. More recent integration of high-resolution imaging modalities with computational modeling has greatly improved our quantitative understanding of hemodynamic flow in heart development. Merging these latest experimental technologies with molecular and genetic signaling analysis will accelerate our understanding of the relationships integrating mechanical and biological signaling for proper cardiac formation. These advances will likely be essential for clinically translatable guidance for targeted interventions to rescue malforming hearts and/or reconfigure malformed circulations for optimal performance. This review summarizes our current understanding on the levels of mechanical signaling in the heart and their roles in orchestrating cardiac development.
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Affiliation(s)
| | - Jonathan T Butcher
- Department of Biomedical Engineering, Cornell University Ithaca, NY, USA
| | - Huseyin C Yalcin
- Department of Mechanical Engineering, Dogus University Istanbul, Turkey
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18
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Chester AH, El-Hamamsy I, Butcher JT, Latif N, Bertazzo S, Yacoub MH. The living aortic valve: From molecules to function. Glob Cardiol Sci Pract 2014; 2014:52-77. [PMID: 25054122 PMCID: PMC4104380 DOI: 10.5339/gcsp.2014.11] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 04/28/2014] [Indexed: 12/12/2022] Open
Abstract
The aortic valve lies in a unique hemodynamic environment, one characterized by a range of stresses (shear stress, bending forces, loading forces and strain) that vary in intensity and direction throughout the cardiac cycle. Yet, despite its changing environment, the aortic valve opens and closes over 100,000 times a day and, in the majority of human beings, will function normally over a lifespan of 70–90 years. Until relatively recently heart valves were considered passive structures that play no active role in the functioning of a valve, or in the maintenance of its integrity and durability. However, through clinical experience and basic research the aortic valve can now be characterized as a living, dynamic organ with the capacity to adapt to its complex mechanical and biomechanical environment through active and passive communication between its constituent parts. The clinical relevance of a living valve substitute in patients requiring aortic valve replacement has been confirmed. This highlights the importance of using tissue engineering to develop heart valve substitutes containing living cells which have the ability to assume the complex functioning of the native valve.
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19
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Qian Z, Mordovanakis A, Schoenly JE, Covarrubias A, Feng Y, Lilge L, Marjoribanks RS. Pulsetrain-burst mode, ultrafast-laser interactions with 3D viable cell cultures as a model for soft biological tissues. BIOMEDICAL OPTICS EXPRESS 2013; 5:208-22. [PMID: 24466488 PMCID: PMC3891333 DOI: 10.1364/boe.5.000208] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 12/05/2013] [Accepted: 12/07/2013] [Indexed: 05/09/2023]
Abstract
A 3D living-cell culture in hydrogel has been developed as a standardized low-tensile-strength tissue proxy for study of ultrafast, pulsetrain-burst laser-tissue interactions. The hydrogel is permeable to fluorescent biomarkers and optically transparent, allowing viable and necrotic cells to be imaged in 3D by confocal microscopy. Good cell-viability allowed us to distinguish between typical cell mortality and delayed subcellular tissue damage (e.g., apoptosis and DNA repair complex formation), caused by laser irradiation. The range of necrosis depended on laser intensity, but not on pulsetrain-burst duration. DNA double-strand breaks were quantified, giving a preliminary upper limit for genetic damage following laser treatment.
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Affiliation(s)
- Zuoming Qian
- Department of Physics, & Institute for Optical Sciences, University of Toronto, 60 St. George Street, Toronto ON M5S 1A7, Canada
| | - Aghapi Mordovanakis
- Department of Physics, & Institute for Optical Sciences, University of Toronto, 60 St. George Street, Toronto ON M5S 1A7, Canada
- Current address: Biomedical Engineering, University of Michigan, 1101 Beal Avenue, Ann Arbor, Michigan 48109, USA
| | - Joshua E. Schoenly
- Department of Physics, & Institute for Optical Sciences, University of Toronto, 60 St. George Street, Toronto ON M5S 1A7, Canada
| | - Andrés Covarrubias
- Department of Physics, & Institute for Optical Sciences, University of Toronto, 60 St. George Street, Toronto ON M5S 1A7, Canada
| | - Yuanfeng Feng
- Department of Physics, & Institute for Optical Sciences, University of Toronto, 60 St. George Street, Toronto ON M5S 1A7, Canada
| | - Lothar Lilge
- Princess Margaret Hospital, Ontario Cancer Institute and Department of Medical Biophysics, University of Toronto, 610 University Ave., Toronto ON M5G 2M9, Canada
| | - Robin S. Marjoribanks
- Department of Physics, & Institute for Optical Sciences, University of Toronto, 60 St. George Street, Toronto ON M5S 1A7, Canada
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20
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Gregg CL, Butcher JT. Translational paradigms in scientific and clinical imaging of cardiac development. ACTA ACUST UNITED AC 2013; 99:106-20. [PMID: 23897595 DOI: 10.1002/bdrc.21034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 05/14/2013] [Indexed: 01/25/2023]
Abstract
Congenital heart defects (CHD) are the most prevalent congenital disease, with 45% of deaths resulting from a congenital defect due to a cardiac malformation. Clinically significant CHD permit survival upon birth, but may become immediately life threatening. Advances in surgical intervention have significantly reduced perinatal mortality, but the outcome for many malformations is bleak. Furthermore, patients living while tolerating a CHD often acquire additional complications due to the long-term systemic blood flow changes caused by even subtle anatomical abnormalities. Accurate diagnosis of defects during fetal development is critical for interventional planning and improving patient outcomes. Advances in quantitative, multidimensional imaging are necessary to uncover the basic scientific and clinically relevant morphogenetic changes and associated hemodynamic consequences influencing normal and abnormal heart development. Ultrasound is the most widely used clinical imaging technology for assessing fetal cardiac development. Ultrasound-based fetal assessment modalities include motion mode (M-mode), two dimensional (2D), and 3D/4D imaging. These datasets can be combined with computational fluid dynamics analysis to yield quantitative, volumetric, and physiological data. Additional imaging modalities, however, are available to study basic mechanisms of cardiogenesis, including optical coherence tomography, microcomputed tomography, and magnetic resonance imaging. Each imaging technology has its advantages and disadvantages regarding resolution, depth of penetration, soft tissue contrast considerations, and cost. In this review, we analyze the current clinical and scientific imaging technologies, research studies utilizing them, and appropriate animal models reflecting clinically relevant cardiogenesis and cardiac malformations. We conclude with discussing the translational impact and future opportunities for cardiovascular development imaging research.
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Affiliation(s)
- Chelsea L Gregg
- Department of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
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21
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Matrone G, Taylor JM, Wilson KS, Baily J, Love GD, Girkin JM, Mullins JJ, Tucker CS, Denvir MA. Laser-targeted ablation of the zebrafish embryonic ventricle: a novel model of cardiac injury and repair. Int J Cardiol 2013; 168:3913-9. [PMID: 23871347 PMCID: PMC3819623 DOI: 10.1016/j.ijcard.2013.06.063] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 05/14/2013] [Accepted: 06/29/2013] [Indexed: 11/23/2022]
Abstract
Background While the adult zebrafish (Danio rerio) heart demonstrates a remarkable capacity for self-renewal following apical resection little is known about the response to injury in the embryonic heart. Methods Injury to the beating zebrafish embryo heart was induced by laser using a transgenic zebrafish expressing cardiomyocyte specific green fluorescent protein. Changes in ejection fraction (EF), heart rate (HR), and caudal vein blood flow (CVBF) assessed by video capture techniques were assessed at 2, 24 and 48 h post-laser. Change in total and mitotic ventricular cardiomyocyte number following laser injury was also assessed by counting respectively DAPI (VCt) and Phospho-histone H3 (VCm) positive nuclei in isolated hearts using confocal microscopy. Results Laser injury to the ventricle resulted in bradycardia and mild bleeding into the pericardium. At 2 h post-laser injury, there was a significant reduction in cardiac performance in lasered-hearts compared with controls (HR 117 ± 11 vs 167 ± 9 bpm, p ≤ 0.001; EF 14.1 ± 1.8 vs 20.1 ± 1.3%, p ≤ 0.001; CVBF 103 ± 15 vs 316 ± 13μms− 1, p ≤ 0.001, respectively). Isolated hearts showed a significant reduction in VCt at 2 h post-laser compared to controls (195 ± 15 vs 238 ± 15, p ≤ 0.05). Histology showed necrosis and apoptosis (TUNEL assay) at the site of laser injury. At 24 h post-laser cardiac performance and VCt had recovered fully to control levels. Pretreatment with the cell-cycle inhibitor, aphidicolin, significantly inhibited functional recovery of the ventricle accompanied by a significant inhibition of cardiomyocyte proliferation. Conclusions Laser-targeted injury of the zebrafish embryonic heart is a novel and reproducible model of cardiac injury and repair suitable for pharmacological and molecular studies.
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Affiliation(s)
- Gianfranco Matrone
- University/BHF Centre for Cardiovascular Science, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, EH16 4TJ, United Kingdom
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22
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Gould RA, Aboulmouna LM, Varner JD, Butcher JT. Hierarchical approaches for systems modeling in cardiac development. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2013; 5:289-305. [PMID: 23463736 DOI: 10.1002/wsbm.1217] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Ordered cardiac morphogenesis and function are essential for all vertebrate life. The heart begins as a simple contractile tube, but quickly grows and morphs into a multichambered pumping organ complete with valves, while maintaining regulation of blood flow and nutrient distribution. Though not identical, cardiac morphogenesis shares many molecular and morphological processes across vertebrate species. Quantitative data across multiple time and length scales have been gathered through decades of reductionist single variable analyses. These range from detailed molecular signaling pathways at the cellular levels to cardiac function at the tissue/organ levels. However, none of these components act in true isolation from others, and each, in turn, exhibits short- and long-range effects in both time and space. With the absence of a gene, entire signaling cascades and genetic profiles may be shifted, resulting in complex feedback mechanisms. Also taking into account local microenvironmental changes throughout development, it is apparent that a systems level approach is an essential resource to accelerate information generation concerning the functional relationships across multiple length scales (molecular data vs physiological function) and structural development. In this review, we discuss relevant in vivo and in vitro experimental approaches, compare different computational frameworks for systems modeling, and the latest information about systems modeling of cardiac development. Finally, we conclude with some important future directions for cardiac systems modeling.
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Affiliation(s)
- Russell A Gould
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, USA
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23
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Buskohl PR, Sun MJ, Thompson RP, Butcher JT. Serotonin potentiates transforming growth factor-beta3 induced biomechanical remodeling in avian embryonic atrioventricular valves. PLoS One 2012; 7:e42527. [PMID: 22880017 PMCID: PMC3412853 DOI: 10.1371/journal.pone.0042527] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 07/09/2012] [Indexed: 01/08/2023] Open
Abstract
Embryonic heart valve primordia (cushions) maintain unidirectional blood flow during development despite an increasingly demanding mechanical environment. Recent studies demonstrate that atrioventricular (AV) cushions stiffen over gestation, but the molecular mechanisms of this process are unknown. Transforming growth factor-beta (TGFβ) and serotonin (5-HT) signaling modulate tissue biomechanics of postnatal valves, but less is known of their role in the biomechanical remodeling of embryonic valves. In this study, we demonstrate that exogenous TGFβ3 increases AV cushion biomechanical stiffness and residual stress, but paradoxically reduces matrix compaction. We then show that TGFβ3 induces contractile gene expression (RhoA, aSMA) and extracellular matrix expression (col1α2) in cushion mesenchyme, while simultaneously stimulating a two-fold increase in proliferation. Local compaction increased due to an elevated contractile phenotype, but global compaction appeared reduced due to proliferation and ECM synthesis. Blockade of TGFβ type I receptors via SB431542 inhibited the TGFβ3 effects. We next showed that exogenous 5-HT does not influence cushion stiffness by itself, but synergistically increases cushion stiffness with TGFβ3 co-treatment. 5-HT increased TGFβ3 gene expression and also potentiated TGFβ3 induced gene expression in a dose-dependent manner. Blockade of the 5HT2b receptor, but not 5-HT2a receptor or serotonin transporter (SERT), resulted in complete cessation of TGFβ3 induced mechanical strengthening. Finally, systemic 5-HT administration in ovo induced cushion remodeling related defects, including thinned/atretic AV valves, ventricular septal defects, and outflow rotation defects. Elevated 5-HT in ovo resulted in elevated remodeling gene expression and increased TGFβ signaling activity, supporting our ex-vivo findings. Collectively, these results highlight TGFβ/5-HT signaling as a potent mechanism for control of biomechanical remodeling of AV cushions during development.
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Affiliation(s)
- Philip R Buskohl
- Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York, United States of America
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24
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Goenezen S, Rennie MY, Rugonyi S. Biomechanics of early cardiac development. Biomech Model Mechanobiol 2012; 11:1187-204. [PMID: 22760547 DOI: 10.1007/s10237-012-0414-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Accepted: 06/20/2012] [Indexed: 12/31/2022]
Abstract
Biomechanics affect early cardiac development, from looping to the development of chambers and valves. Hemodynamic forces are essential for proper cardiac development, and their disruption leads to congenital heart defects. A wealth of information already exists on early cardiac adaptations to hemodynamic loading, and new technologies, including high-resolution imaging modalities and computational modeling, are enabling a more thorough understanding of relationships between hemodynamics and cardiac development. Imaging and modeling approaches, used in combination with biological data on cell behavior and adaptation, are paving the road for new discoveries on links between biomechanics and biology and their effect on cardiac development and fetal programming.
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Affiliation(s)
- Sevan Goenezen
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR 97239, USA.
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Gregg CL, Butcher JT. Quantitative in vivo imaging of embryonic development: opportunities and challenges. Differentiation 2012; 84:149-62. [PMID: 22695188 DOI: 10.1016/j.diff.2012.05.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 05/03/2012] [Accepted: 05/04/2012] [Indexed: 10/28/2022]
Abstract
Animal models are critically important for a mechanistic understanding of embryonic morphogenesis. For decades, visualizing these rapid and complex multidimensional events has relied on projection images and thin section reconstructions. While much insight has been gained, fixed tissue specimens offer limited information on dynamic processes that are essential for tissue assembly and organ patterning. Quantitative imaging is required to unlock the important basic science and clinically relevant secrets that remain hidden. Recent advances in live imaging technology have enabled quantitative longitudinal analysis of embryonic morphogenesis at multiple length and time scales. Four different imaging modalities are currently being used to monitor embryonic morphogenesis: optical, ultrasound, magnetic resonance imaging (MRI), and micro-computed tomography (micro-CT). Each has its advantages and limitations with respect to spatial resolution, depth of field, scanning speed, and tissue contrast. In addition, new processing tools have been developed to enhance live imaging capabilities. In this review, we analyze each type of imaging source and its use in quantitative study of embryonic morphogenesis in small animal models. We describe the physics behind their function, identify some examples in which the modality has revealed new quantitative insights, and then conclude with a discussion of new research directions with live imaging.
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Affiliation(s)
- Chelsea L Gregg
- Department of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
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Bharadwaj KN, Spitz C, Shekhar A, Yalcin HC, Butcher JT. Computational fluid dynamics of developing avian outflow tract heart valves. Ann Biomed Eng 2012; 40:2212-27. [PMID: 22535311 DOI: 10.1007/s10439-012-0574-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Accepted: 04/11/2012] [Indexed: 11/28/2022]
Abstract
Hemodynamic forces play an important role in sculpting the embryonic heart and its valves. Alteration of blood flow patterns through the hearts of embryonic animal models lead to malformations that resemble some clinical congenital heart defects, but the precise mechanisms are poorly understood. Quantitative understanding of the local fluid forces acting in the heart has been elusive because of the extremely small and rapidly changing anatomy. In this study, we combine multiple imaging modalities with computational simulation to rigorously quantify the hemodynamic environment within the developing outflow tract (OFT) and its eventual aortic and pulmonary valves. In vivo Doppler ultrasound generated velocity profiles were applied to Micro-Computed Tomography generated 3D OFT lumen geometries from Hamburger-Hamilton (HH) stage 16-30 chick embryos. Computational fluid dynamics simulation initial conditions were iterated until local flow profiles converged with in vivo Doppler flow measurements. Results suggested that flow in the early tubular OFT (HH16 and HH23) was best approximated by Poiseuille flow, while later embryonic OFT septation (HH27, HH30) was mimicked by plug flow conditions. Peak wall shear stress (WSS) values increased from 18.16 dynes/cm(2) at HH16 to 671.24 dynes/cm(2) at HH30. Spatiotemporally averaged WSS values also showed a monotonic increase from 3.03 dynes/cm(2) at HH16 to 136.50 dynes/cm(2) at HH30. Simulated velocity streamlines in the early heart suggest a lack of mixing, which differed from classical ink injections. Changes in local flow patterns preceded and correlated with key morphogenetic events such as OFT septation and valve formation. This novel method to quantify local dynamic hemodynamics parameters affords insight into sculpting role of blood flow in the embryonic heart and provides a quantitative baseline dataset for future research.
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Affiliation(s)
- Koonal N Bharadwaj
- Department of Biomedical Engineering, Cornell University, Ithaca, NY 14853-7501, USA
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Jeong D, Tsai PS, Kleinfeld D. Prospect for feedback guided surgery with ultra-short pulsed laser light. Curr Opin Neurobiol 2012; 22:24-33. [PMID: 22088392 PMCID: PMC3763077 DOI: 10.1016/j.conb.2011.10.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2011] [Revised: 10/20/2011] [Accepted: 10/24/2011] [Indexed: 11/29/2022]
Abstract
The controlled cutting of tissue with laser light is a natural technology to combine with automated stereotaxic surgery. A central challenge is to cut hard tissue, such as bone, without inducing damage to juxtaposed soft tissue, such as nerve and dura. We review past work that demonstrates the feasibility of such control through the use of ultrafast laser light to both cut and generate optical feedback signals via second harmonic generation and laser induced plasma spectra.
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Affiliation(s)
- Diana Jeong
- Department of Physics, University of California at San Diego, La Jolla, CA
| | - Philbert S. Tsai
- Department of Physics, University of California at San Diego, La Jolla, CA
| | - David Kleinfeld
- Department of Physics, University of California at San Diego, La Jolla, CA
- Section of Neurobiology, University of California at San Diego, La Jolla, CA
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Abstract
Abstract
The formation and remodeling of the embryonic valves is a complex and dynamic process that occurs within a constantly changing hemodynamic environment. Defects in embryonic and fetal valve remodeling are the leading cause of congenital heart defects, yet very little is known about how fibrous leaflet tissue is created from amorphous gelatinous masses called cushions. Microenvironmental cues such as mechanical forces and extracellular matrix composition play major roles in cell differentiation, but almost all research efforts in valvulogenesis center around genetics and molecular approaches. This review summarizes what is known about the dynamic mechanical and extracellular matrix microenvironment of the atrioventricular and semilunar valves during embryonic development and their possible guidance roles. A variety of new computational tools and sophisticated experimental techniques are progressing that enable precise microenvironmental alterations that are critical to complement genetic gain and loss of function approaches. Studies at the interface of mechanical and genetic signaling in embryonic valvulogenesis will likely pay significant dividends, not only in terms of increasing our mechanistic understanding, but also lead to the development of novel therapeutic strategies for patients with congenital valve abnormalities.
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Affiliation(s)
| | - Jonathan T. Butcher
- Department of Biomedical Engineering, Cornell University, Ithaca, NY 14850, USA
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Henning AL, Jiang MX, Yalcin HC, Butcher JT. Quantitative three-dimensional imaging of live avian embryonic morphogenesis via micro-computed tomography. Dev Dyn 2011; 240:1949-57. [PMID: 21761480 DOI: 10.1002/dvdy.22694] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Many clinically relevant congenital malformations arise during mid to late embryonic stages. This period is challenging to image quantitatively in live embryos, necessitating the use of multiple specimens with increased experimental variability. Here we establish X-ray and blood-pool computed tomography (CT) contrast agent toxicity and teratogenesis thresholds for 3D Micro-CT imaging of live avian embryos. Day 4 chick embryos micro-injected with Visipaque™ (VP) developed for an additional 6 days without defect. X-ray radiation up to 798 mGy was nontoxic. Peak average contrast of 1,060 HU occurred within 1 hr of imaging at 50 μm resolution. VP-enhanced contrast persisted past 24 hr with delayed accumulation in the allantois. Regional volumes of VP-injected embryos were statistically identical to those of fixed embryos perfused with osmium tetroxide. We further quantified longitudinal volumetric morphogenesis of the allantois over 30 hr. These results demonstrate the safety and efficacy of contrast enhanced quantitative micro-CT imaging for live embryos.
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Affiliation(s)
- Alyssa L Henning
- Department of Biomedical Engineering, Cornell University, Ithaca, New York 14853-7501, USA
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Mondia JP, Levin M, Omenetto FG, Orendorff RD, Branch MR, Adams DS. Long-distance signals are required for morphogenesis of the regenerating Xenopus tadpole tail, as shown by femtosecond-laser ablation. PLoS One 2011; 6:e24953. [PMID: 21949803 PMCID: PMC3174989 DOI: 10.1371/journal.pone.0024953] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Accepted: 08/25/2011] [Indexed: 12/15/2022] Open
Abstract
Background With the goal of learning to induce regeneration in human beings as a treatment for tissue loss, research is being conducted into the molecular and physiological details of the regeneration process. The tail of Xenopus laevis tadpoles has recently emerged as an important model for these studies; we explored the role of the spinal cord during tadpole tail regeneration. Methods and Results Using ultrafast lasers to ablate cells, and Geometric Morphometrics to quantitatively analyze regenerate morphology, we explored the influence of different cell populations. For at least twenty-four hours after amputation (hpa), laser-induced damage to the dorsal midline affected the morphology of the regenerated tail; damage induced 48 hpa or later did not. Targeting different positions along the anterior-posterior (AP) axis caused different shape changes in the regenerate. Interestingly, damaging two positions affected regenerate morphology in a qualitatively different way than did damaging either position alone. Quantitative comparison of regenerate shapes provided strong evidence against a gradient and for the existence of position-specific morphogenetic information along the entire AP axis. Conclusions We infer that there is a conduit of morphology-influencing information that requires a continuous dorsal midline, particularly an undamaged spinal cord. Contrary to expectation, this information is not in a gradient and it is not localized to the regeneration bud. We present a model of morphogenetic information flow from tissue undamaged by amputation and conclude that studies of information coming from far outside the amputation plane and regeneration bud will be critical for understanding regeneration and for translating fundamental understanding into biomedical approaches.
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Affiliation(s)
- Jessica P. Mondia
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, United States of America
| | - Michael Levin
- Department of Biology and Center for Regenerative and Developmental Biology, Tufts University, Medford, Massachusetts, United States of America
| | - Fiorenzo G. Omenetto
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, United States of America
| | - Ryan D. Orendorff
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, United States of America
| | - Mary Rose Branch
- Department of Biology and Center for Regenerative and Developmental Biology, Tufts University, Medford, Massachusetts, United States of America
| | - Dany Spencer Adams
- Department of Biology and Center for Regenerative and Developmental Biology, Tufts University, Medford, Massachusetts, United States of America
- * E-mail:
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Mojzisova H, Vermot J. When multiphoton microscopy sees near infrared. Curr Opin Genet Dev 2011; 21:549-57. [PMID: 21924603 DOI: 10.1016/j.gde.2011.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 07/29/2011] [Accepted: 08/11/2011] [Indexed: 12/11/2022]
Abstract
The need for quantification and real time visualization of developmental processes has called for increasingly sophisticated imaging techniques. Among them, multiphoton microscopy reveals itself to be an extremely versatile tool owing to its unique ability to combine fluorescent imaging, laser ablation, and higher harmonic generation. Furthermore, recent advances in femtosecond lasers and optical parametric oscillators (OPO) are now opening doors for imaging at unprecedented wavelengths centered in the tissue transparency window. This Review describes promising multiphoton approaches using OPO and the growing number of useful applications of non-linear microscopy in the field of developmental biology. Basic characteristics associated with these techniques are described along with the main experimental challenges when applied to embryo imaging.
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Affiliation(s)
- Halina Mojzisova
- IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), Inserm U964, CNRS UMR7104, Université de Strasbourg, 1 rue Laurent Fries, Illkirch F-67404, France
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