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Wu L, van Heugten MH, van den Bosch TPP, Duimel H, López-Iglesias C, Hesselink DA, Baan CC, Boer K. Polarized HLA Class I Expression on Renal Tubules Hinders the Detection of Donor-Specific Urinary Extracellular Vesicles. Int J Nanomedicine 2024; 19:3497-3511. [PMID: 38628433 PMCID: PMC11020244 DOI: 10.2147/ijn.s446525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 03/27/2024] [Indexed: 04/19/2024] Open
Abstract
Purpose Kidney transplantation is the optimal treatment for patients with end-stage kidney disease. Donor-specific urinary extracellular vesicles (uEVs) hold potential as biomarkers for assessing allograft status. We aimed to develop a method for identifying donor-specific uEVs based on human leukocyte antigen (HLA) mismatching with the kidney transplant recipients (KTRs). Patients and Methods Urine and plasma were obtained from HLA-A2+ donors and HLA-A2- KTRs pre-transplant. CD9 (tetraspanin, EV marker) and HLA-A2 double-positive (CD9+ HLA-A2+) EVs were quantified using isolation-free imaging flow cytometry (IFCM). Healthy individuals' urine was used to investigate CD9+ HLA-class-I+ uEV quantification using IFCM, time-resolved fluoroimmunoassay (TR-FIA), and immunogold staining cryo-electron microscopy (cryo-EM). Culture-derived CD9+ HLA-class-I+ EVs were spiked into the urine to investigate urine matrix effects on uEV HLA detection. Deceased donor kidneys and peritumoral kidney tissue were used for HLA class I detection with histochemistry. Results The concentrations of CD9+ HLA-A2+ EVs in both donor and recipient urine approached the negative (detergent-treated) control levels for IFCM and were significantly lower than those observed in donor plasma. In parallel, universal HLA class I+ uEVs were similarly undetectable in the urine and uEV isolates compared with plasma, as verified by IFCM, TR-FIA, and cryogenic electron microscopy. Culture supernatant containing HLA class I+ vesicles from B, T, and human proximal tubule cells were spiked into the urine, and these EVs remained stable at 37°C for 8 hours. Immunohistochemistry revealed that HLA class I was predominantly expressed on the basolateral side of renal tubules, with limited expression on their urine/apical side. Conclusion The detection of donor-specific uEVs is hindered by the limited release of HLA class I+ EVs from the kidney into the urine, primarily due to the polarized HLA class I expression on renal tubules. Identifying donor-specific uEVs requires further advancements in recognizing transplant-specific uEVs and urine-associated markers.
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Affiliation(s)
- Liang Wu
- Department of Nephrology, the First Affiliated Hospital of Shaoyang University, Shaoyang, Hunan, People’s Republic of China
- Erasmus MC Transplant Institute, University Medical Center Rotterdam, Department of Internal Medicine, Division of Nephrology and Transplantation, Rotterdam, the Netherlands
| | - Martijn H van Heugten
- University Medical Center Rotterdam, Department of Internal Medicine, Division of Nephrology and Transplantation, Rotterdam, the Netherlands
| | | | - Hans Duimel
- The Microscopy CORE Laboratory at the Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, the Netherlands
| | - Carmen López-Iglesias
- The Microscopy CORE Laboratory at the Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, the Netherlands
| | - Dennis A Hesselink
- Erasmus MC Transplant Institute, University Medical Center Rotterdam, Department of Internal Medicine, Division of Nephrology and Transplantation, Rotterdam, the Netherlands
| | - Carla C Baan
- Erasmus MC Transplant Institute, University Medical Center Rotterdam, Department of Internal Medicine, Division of Nephrology and Transplantation, Rotterdam, the Netherlands
| | - Karin Boer
- Erasmus MC Transplant Institute, University Medical Center Rotterdam, Department of Internal Medicine, Division of Nephrology and Transplantation, Rotterdam, the Netherlands
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2
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Vermeulen S, Knoops K, Duimel H, Parvizifard M, van Beurden D, López-Iglesias C, Giselbrecht S, Truckenmüller R, Habibović P, Tahmasebi Birgani Z. An in vitro model system based on calcium- and phosphate ion-induced hMSC spheroid mineralization. Mater Today Bio 2023; 23:100844. [PMID: 38033367 PMCID: PMC10682137 DOI: 10.1016/j.mtbio.2023.100844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 10/15/2023] [Accepted: 10/23/2023] [Indexed: 12/02/2023] Open
Abstract
A challenge in regenerative medicine is creating the three-dimensional organic and inorganic in vitro microenvironment of bone, which would allow the study of musculoskeletal disorders and the generation of building blocks for bone regeneration. This study presents a microwell-based platform for creating spheroids of human mesenchymal stromal cells, which are then mineralized using ionic calcium and phosphate supplementation. The resulting mineralized spheroids promote an osteogenic gene expression profile through the influence of the spheroids' biophysical environment and inorganic signaling and require less calcium or phosphate to achieve mineralization compared to a monolayer culture. We found that mineralized spheroids represent an in vitro model for studying small molecule perturbations and extracellular mediated calcification. Furthermore, we demonstrate that understanding pathway signaling elicited by the spheroid environment allows mimicking these pathways in traditional monolayer culture, enabling similar rapid mineralization events. In sum, this study demonstrates the rapid generation and employment of a mineralized cell model system for regenerative medicine applications.
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Affiliation(s)
- Steven Vermeulen
- Department of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, the Netherlands
| | - Kèvin Knoops
- Microscopy CORE Lab, M4I Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, the Netherlands
| | - Hans Duimel
- Microscopy CORE Lab, M4I Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, the Netherlands
| | - Maryam Parvizifard
- Department of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, the Netherlands
| | - Denis van Beurden
- Department of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, the Netherlands
| | - Carmen López-Iglesias
- Microscopy CORE Lab, M4I Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, the Netherlands
| | - Stefan Giselbrecht
- Department of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, the Netherlands
| | - Roman Truckenmüller
- Department of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, the Netherlands
| | - Pamela Habibović
- Department of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, the Netherlands
| | - Zeinab Tahmasebi Birgani
- Department of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, the Netherlands
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Hafeez S, Decarli MC, Aldana A, Ebrahimi M, Ruiter FAA, Duimel H, van Blitterswijk C, Pitet LM, Moroni L, Baker MB. In Situ Covalent Reinforcement of a Benzene-1,3,5-Tricarboxamide Supramolecular Polymer Enables Biomimetic, Tough, and Fibrous Hydrogels and Bioinks. Adv Mater 2023; 35:e2301242. [PMID: 37370137 DOI: 10.1002/adma.202301242] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 04/25/2023] [Accepted: 05/16/2023] [Indexed: 06/29/2023]
Abstract
Synthetic hydrogels often lack the load-bearing capacity and mechanical properties of native biopolymers found in tissue, such as cartilage. In natural tissues, toughness is often imparted via the combination of fibrous noncovalent self-assembly with key covalent bond formation. This controlled combination of supramolecular and covalent interactions remains difficult to engineer, yet can provide a clear strategy for advanced biomaterials. Here, a synthetic supramolecular/covalent strategy is investigated for creating a tough hydrogel that embodies the hierarchical fibrous architecture of the extracellular matrix (ECM). A benzene-1,3,5-tricarboxamide (BTA) hydrogelator is developed with synthetically addressable norbornene handles that self-assembles to form a and viscoelastic hydrogel. Inspired by collagen's covalent cross-linking of fibrils, the mechanical properties are reinforced by covalent intra- and interfiber cross-links. At over 90% water, the hydrogels withstand up to 550% tensile strain, 90% compressive strain, and dissipated energy with recoverable hysteresis. The hydrogels are shear-thinning, can be 3D bioprinted with good shape fidelity, and can be toughened via covalent cross-linking. These materials enable the bioprinting of human mesenchymal stromal cell (hMSC) spheroids and subsequent differentiation into chondrogenic tissue. Collectively, these findings highlight the power of covalent reinforcement of supramolecular fibers, offering a strategy for the bottom-up design of dynamic, yet tough, hydrogels and bioinks.
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Affiliation(s)
- Shahzad Hafeez
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Monize Caiado Decarli
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Agustina Aldana
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Mahsa Ebrahimi
- Advanced Functional Polymers Group, Department of Chemistry, Institute for Materials Research (IMO), Hasselt University, Martelarenlaan 42, Hasselt, 3500, Belgium
| | - Floor A A Ruiter
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
- Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology- Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Hans Duimel
- Maastricht MultiModal Molecular Imaging Institute, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Clemens van Blitterswijk
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Louis M Pitet
- Advanced Functional Polymers Group, Department of Chemistry, Institute for Materials Research (IMO), Hasselt University, Martelarenlaan 42, Hasselt, 3500, Belgium
| | - Lorenzo Moroni
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Matthew B Baker
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
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4
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Zhang Y, van Schayck JP, Pedrazo-Tardajos A, Claes N, Noteborn WEM, Lu PH, Duimel H, Dunin-Borkowski RE, Bals S, Peters PJ, Ravelli RBG. Charging of Vitreous Samples in Cryogenic Electron Microscopy Mitigated by Graphene. ACS Nano 2023; 17:15836-15846. [PMID: 37531407 PMCID: PMC10448747 DOI: 10.1021/acsnano.3c03722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 07/25/2023] [Indexed: 08/04/2023]
Abstract
Cryogenic electron microscopy can provide high-resolution reconstructions of macromolecules embedded in a thin layer of ice from which atomic models can be built de novo. However, the interaction between the ionizing electron beam and the sample results in beam-induced motion and image distortion, which limit the attainable resolutions. Sample charging is one contributing factor of beam-induced motions and image distortions, which is normally alleviated by including part of the supporting conducting film within the beam-exposed region. However, routine data collection schemes avoid strategies whereby the beam is not in contact with the supporting film, whose rationale is not fully understood. Here we characterize electrostatic charging of vitreous samples, both in imaging and in diffraction mode. We mitigate sample charging by depositing a single layer of conductive graphene on top of regular EM grids. We obtained high-resolution single-particle analysis (SPA) reconstructions at 2 Å when the electron beam only irradiates the middle of the hole on graphene-coated grids, using data collection schemes that previously failed to produce sub 3 Å reconstructions without the graphene layer. We also observe that the SPA data obtained with the graphene-coated grids exhibit a higher b factor and reduced particle movement compared to data obtained without the graphene layer. This mitigation of charging could have broad implications for various EM techniques, including SPA and cryotomography, and for the study of radiation damage and the development of future sample carriers. Furthermore, it may facilitate the exploration of more dose-efficient, scanning transmission EM based SPA techniques.
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Affiliation(s)
- Yue Zhang
- Maastricht
MultiModal Molecular Imaging Institute (M4i), Maastricht University, 6200 MD Maastricht, The Netherlands
| | - J. Paul van Schayck
- Maastricht
MultiModal Molecular Imaging Institute (M4i), Maastricht University, 6200 MD Maastricht, The Netherlands
| | - Adrián Pedrazo-Tardajos
- Electron
Microscopy for Materials Science (EMAT), University of Antwerp, Antwerp 2020, Belgium
- NANOlab
Center of Excellence, University of Antwerp, 2020 Antwerp, Belgium
| | - Nathalie Claes
- Electron
Microscopy for Materials Science (EMAT), University of Antwerp, Antwerp 2020, Belgium
- NANOlab
Center of Excellence, University of Antwerp, 2020 Antwerp, Belgium
| | - Willem E. M. Noteborn
- Netherlands
Centre for Electron Nanoscopy (NeCEN), Leiden
University, 2300 RS Leiden, The Netherlands
| | - Peng-Han Lu
- Ernst
Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter
Grünberg Institute, Forschungszentrum
Jülich, 52425 Jülich, Germany
| | - Hans Duimel
- Maastricht
MultiModal Molecular Imaging Institute (M4i), Maastricht University, 6200 MD Maastricht, The Netherlands
| | - Rafal E. Dunin-Borkowski
- Ernst
Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter
Grünberg Institute, Forschungszentrum
Jülich, 52425 Jülich, Germany
| | - Sara Bals
- Electron
Microscopy for Materials Science (EMAT), University of Antwerp, Antwerp 2020, Belgium
- NANOlab
Center of Excellence, University of Antwerp, 2020 Antwerp, Belgium
| | - Peter J. Peters
- Maastricht
MultiModal Molecular Imaging Institute (M4i), Maastricht University, 6200 MD Maastricht, The Netherlands
| | - Raimond B. G. Ravelli
- Maastricht
MultiModal Molecular Imaging Institute (M4i), Maastricht University, 6200 MD Maastricht, The Netherlands
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5
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Hafeez S, Aldana AA, Duimel H, Ruiter FAA, Decarli MC, Lapointe V, van Blitterswijk C, Moroni L, Baker MB. Molecular Tuning of a Benzene-1,3,5-Tricarboxamide Supramolecular Fibrous Hydrogel Enables Control over Viscoelasticity and Creates Tunable ECM-Mimetic Hydrogels and Bioinks. Adv Mater 2023; 35:e2207053. [PMID: 36858040 DOI: 10.1002/adma.202207053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 02/13/2023] [Indexed: 06/16/2023]
Abstract
Traditional synthetic covalent hydrogels lack the native tissue dynamics and hierarchical fibrous structure found in the extracellular matrix (ECM). These dynamics and fibrous nanostructures are imperative in obtaining the correct cell/material interactions. Consequently, the challenge to engineer functional dynamics in a fibrous hydrogel and recapitulate native ECM properties remains a bottle-neck to biomimetic hydrogel environments. Here, the molecular tuning of a supramolecular benzene-1,3,5-tricarboxamide (BTA) hydrogelator via simple modulation of hydrophobic substituents is reported. This tuning results in fibrous hydrogels with accessible viscoelasticity over 5 orders of magnitude, while maintaining a constant equilibrium storage modulus. BTA hydrogelators are created with systematic variations in the number of hydrophobic carbon atoms, and this is observed to control the viscoelasticity and stress-relaxation timescales in a logarithmic fashion. Some of these BTA hydrogels are shear-thinning, self-healing, extrudable, and injectable, and can be 3D printed into multiple layers. These hydrogels show high cell viability for chondrocytes and human mesenchymal stem cells, establishing their use in tissue engineering applications. This simple molecular tuning by changing hydrophobicity (with just a few carbon atoms) provides precise control over the viscoelasticity and 3D printability in fibrillar hydrogels and can be ported onto other 1D self-assembling structures. The molecular control and design of hydrogel network dynamics can push the field of supramolecular chemistry toward the design of new ECM-mimicking hydrogelators for numerous cell-culture and tissue-engineering applications and give access toward highly biomimetic bioinks for bioprinting.
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Affiliation(s)
- Shahzad Hafeez
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Ana A Aldana
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Hans Duimel
- Maastricht MultiModal Molecular Imaging (M4I) Institute, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Floor A A Ruiter
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
- Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Monize Caiado Decarli
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Vanessa Lapointe
- Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Clemens van Blitterswijk
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Lorenzo Moroni
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
| | - Matthew B Baker
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, Maastricht, 6200 MD, The Netherlands
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6
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van Smaalen TC, Beurskens DMH, Kox JJHFM, Polonia R, Vos R, Duimel H, van de Wetering WJ, López-Iglesias C, Reutelingsperger CP, Ernest van Heurn LW, Peutz-Kootstra CJ, Nicolaes GAF. Extracellular histone release by renal cells after warm and cold ischemic kidney injury: Studies in an ex-vivo porcine kidney perfusion model. PLoS One 2023; 18:e0279944. [PMID: 36662718 PMCID: PMC9858092 DOI: 10.1371/journal.pone.0279944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 12/17/2022] [Indexed: 01/21/2023] Open
Abstract
Extracellular histones are cytotoxic molecules involved in experimental acute kidney injury. In patients receiving a renal transplant from donors after circulatory death, who suffer from additional warm ischemia, worse graft outcome is associated with higher machine perfusate extracellular histone H3 concentrations. We now investigated temperature-dependent extracellular histone release in an ex vivo porcine renal perfusion model, and subsequently studied histone release in the absence and presence of non-anticoagulant heparin. Seven pairs of ischemically damaged porcine kidneys were machine perfused at 4°C (cold ischemia) or 28°C (warm ischemia). Perfusate histone H3 concentration was higher after warm as compared to cold ischemia (median (IQR) = 0.48 (0.20-0.83) μg/mL vs. 0.02 (0.00-0.06) μg/mL; p = .045, respectively). Employing immune-electron microscopy (EM), histone containing cytoplasmic protrusions of tubular and endothelial cells were found after warm ischemic injury. Furthermore, abundant histone localization was detected in debris surrounding severely damaged glomerular cells, in a "buck shot" pattern. In vitro, histones were cytotoxic to endothelial and kidney epithelial cells in a temperature-dependent manner. In a separate ex vivo experiment, addition of heparin did not change the total histone H3 levels observed in the perfusate but revealed a continuous increase in the level of a lower molecular weight histone H3 variant. Our findings show that ischemically damaged kidneys release more extracellular histones in warm ischemia, which by EM was due to histone release by renal cells. Blocking of histone-mediated damage during transplantation may be beneficial in prevention of renal injury.
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Affiliation(s)
- Tim C. van Smaalen
- Department of Surgery, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Danielle M. H. Beurskens
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Jasper J. H. F. M. Kox
- Department of Surgery, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Rasheendra Polonia
- Department of Surgery, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Rein Vos
- Department of Methodology and Statistics, School for Public Health and Primary Care (CAPHRI), Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Hans Duimel
- Microscopy CORE Lab, Maastricht Multimodal Molecular Imaging Institute, FHML, Maastricht University, Maastricht, The Netherlands
| | - Willine J. van de Wetering
- Microscopy CORE Lab, Maastricht Multimodal Molecular Imaging Institute, FHML, Maastricht University, Maastricht, The Netherlands
| | - Carmen López-Iglesias
- Microscopy CORE Lab, Maastricht Multimodal Molecular Imaging Institute, FHML, Maastricht University, Maastricht, The Netherlands
| | - Chris P. Reutelingsperger
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - L. W. Ernest van Heurn
- Department of Surgery, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Carine J. Peutz-Kootstra
- Department of Pathology, Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands
| | - Gerry A. F. Nicolaes
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
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Hafeez S, Ooi HW, Suylen D, Duimel H, Hackeng TM, van Blitterswijk C, Baker MB. Desymmetrization via Activated Esters Enables Rapid Synthesis of Multifunctional Benzene-1,3,5-tricarboxamides and Creation of Supramolecular Hydrogelators. J Am Chem Soc 2022; 144:4057-4070. [PMID: 35196454 PMCID: PMC8915260 DOI: 10.1021/jacs.1c12685] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Supramolecular materials based on the self-assembly of benzene-1,3,5-tricarboxamide (BTA) offer an approach to mimic fibrous self-assembled proteins found in numerous natural systems. Yet, synthetic methods to rapidly build complexity, scalability, and multifunctionality into BTA-based materials are needed. The diversity of BTA structures is often hampered by the limited flexibility of existing desymmetrization routes and the purification of multifunctional BTAs. To alleviate this bottleneck, we have developed a desymmetrization method based on activated ester coupling of a symmetric synthon. We created a small library of activated ester synthons and found that a pentafluorophenol benzene triester (BTE) enabled effective desymmetrization and creation of multifunctional BTAs in good yield with high reaction fidelity. This new methodology enabled the rapid synthesis of a small library of BTA monomers with hydrophobic and/or orthogonal reactive handles and could be extended to create polymeric BTA hydrogelators. These BTA hydrogelators self-assembled in water to create fiber and fibrous sheet-like structures as observed by cryo-TEM, and the identity of the BTA conjugated can tune the mechanical properties of the hydrogel. These hydrogelators display high cytocompatibility for chondrocytes, indicating potential for the use of these systems in 3D cell culture and tissue engineering applications. This newly developed synthetic strategy facilitates the simple and rapid creation of chemically diverse BTA supramolecular polymers, and the newly developed and scalable hydrogels can unlock exploration of BTA based materials in a wider variety of tissue engineering applications.
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Affiliation(s)
- Shahzad Hafeez
- Department of Complex Tissue Regeneration, MERLN Institute for Technology Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Huey Wen Ooi
- Department of Complex Tissue Regeneration, MERLN Institute for Technology Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Dennis Suylen
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Hans Duimel
- Maastricht MultiModal Molecular Imaging Institute (M4i), Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Tilman M Hackeng
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Clemens van Blitterswijk
- Department of Complex Tissue Regeneration, MERLN Institute for Technology Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Matthew B Baker
- Department of Complex Tissue Regeneration, MERLN Institute for Technology Inspired Regenerative Medicine, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
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8
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Keulers TG, Libregts SF, Beaumont JE, Savelkouls KG, Bussink J, Duimel H, Dubois L, Zonneveld MI, López‐Iglesias C, Bezstarosti K, Demmers JA, Vooijs M, Wauben M, Rouschop KM. Secretion of pro-angiogenic extracellular vesicles during hypoxia is dependent on the autophagy-related protein GABARAPL1. J Extracell Vesicles 2021; 10:e12166. [PMID: 34859607 PMCID: PMC8640512 DOI: 10.1002/jev2.12166] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 10/21/2021] [Accepted: 11/02/2021] [Indexed: 12/29/2022] Open
Abstract
Tumour hypoxia is a hallmark of solid tumours and contributes to tumour progression, metastasis development and therapy resistance. In response to hypoxia, tumour cells secrete pro-angiogenic factors to induce blood vessel formation and restore oxygen supply to hypoxic regions. Extracellular vesicles (EVs) are emerging as mediators of intercellular communication in the tumour microenvironment. Here we demonstrate that increased expression of the LC3/GABARAP protein family member GABARAPL1, is required for endosomal maturation, sorting of cargo to endosomes and the secretion of EVs. Silencing GABARAPL1 results in a block in the early endosomal pathway and impaired secretion of EVs with pro-angiogenic properties. Tumour xenografts of doxycycline inducible GABARAPL1 knockdown cells display impaired vascularisation that results in decreased tumour growth, elevated tumour necrosis and increased therapy efficacy. Moreover, our data show that GABARAPL1 is expressed on the EV surface and targeting GABARAPL1+ EVs with GABARAPL1 targeting antibodies results in blockade of pro-angiogenic effects in vitro. In summary, we reveal that GABARAPL1 is required for EV cargo loading and secretion. GABARAPL1+ EVs are detectable and targetable and are therefore interesting to pursue as a therapeutic target.
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Affiliation(s)
- Tom G. Keulers
- Department of Radiation Oncology Radiation Oncology (Maastro) / GROW – School for Oncology and Developmental BiologyMaastricht University Medical Centre +MaastrichtNetherlands
| | - Sten F. Libregts
- Department of Biomolecular Health SciencesFaculty of Veterinary MedicineUtrecht UniversityUtrechtNetherlands
| | - Joel E.J. Beaumont
- Department of Radiation Oncology Radiation Oncology (Maastro) / GROW – School for Oncology and Developmental BiologyMaastricht University Medical Centre +MaastrichtNetherlands
| | - Kim G. Savelkouls
- Department of Radiation Oncology Radiation Oncology (Maastro) / GROW – School for Oncology and Developmental BiologyMaastricht University Medical Centre +MaastrichtNetherlands
| | - Johan Bussink
- Department of Radiation OncologyRadboud University Medical CenterNijmegenNetherlands
| | - Hans Duimel
- Microscopy CORE LabMaastricht Multimodal Molecular Imaging InstituteFHML Division of NanoscopyUniversity of MaastrichtMaastrichtNetherlands
| | - Ludwig Dubois
- The M‐LabDepartment of Precision MedicineGROW ‐ School of OncologyMaastricht UniversityMaastrichtNetherlands
| | - Marijke I. Zonneveld
- Department of Radiation Oncology Radiation Oncology (Maastro) / GROW – School for Oncology and Developmental BiologyMaastricht University Medical Centre +MaastrichtNetherlands
| | - Carmen López‐Iglesias
- Microscopy CORE LabMaastricht Multimodal Molecular Imaging InstituteFHML Division of NanoscopyUniversity of MaastrichtMaastrichtNetherlands
| | - Karel Bezstarosti
- Proteomics CenterErasmus University Medical CenterRotterdamNetherlands
| | - Jeroen A. Demmers
- Proteomics CenterErasmus University Medical CenterRotterdamNetherlands
| | - Marc Vooijs
- Department of Radiation Oncology Radiation Oncology (Maastro) / GROW – School for Oncology and Developmental BiologyMaastricht University Medical Centre +MaastrichtNetherlands
| | - Marca Wauben
- Department of Biomolecular Health SciencesFaculty of Veterinary MedicineUtrecht UniversityUtrechtNetherlands
| | - Kasper M.A. Rouschop
- Department of Radiation Oncology Radiation Oncology (Maastro) / GROW – School for Oncology and Developmental BiologyMaastricht University Medical Centre +MaastrichtNetherlands
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9
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Jiao L, Eickhoff R, Egners A, Jumpertz S, Roth J, Erdem M, Kroh A, Duimel H, López-Iglesias C, Caro P, Heij LR, Schmeding M, Meierhofer D, Neumann UP, Cramer T. Deletion of mTOR in liver epithelial cells enhances hepatic metastasis of colon cancer. J Pathol 2021; 255:270-284. [PMID: 34309874 DOI: 10.1002/path.5768] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 07/02/2021] [Accepted: 07/21/2021] [Indexed: 12/21/2022]
Abstract
Activation of the mechanistic target of rapamycin (mTOR) pathway is frequently found in cancer, but mTOR inhibitors have thus far failed to demonstrate significant antiproliferative efficacy in the majority of cancer types. Besides cancer cell-intrinsic resistance mechanisms, it is conceivable that mTOR inhibitors impact on non-malignant host cells in a manner that ultimately supports resistance of cancer cells. Against this background, we sought to analyze the functional consequences of mTOR inhibition in hepatocytes for the growth of metastatic colon cancer. To this end, we established liver epithelial cell (LEC)-specific knockout (KO) of mTOR (mTORLEC ) mice. We used these mice to characterize the growth of colorectal liver metastases with or without partial hepatectomy to model different clinical settings. Although the LEC-specific loss of mTOR remained without effect on metastasis growth in intact liver, partial liver resection resulted in the formation of larger metastases in mTORLEC mice compared with wildtype controls. This was accompanied by significantly enhanced inflammatory activity in LEC-specific mTOR KO livers after partial liver resection. Analysis of NF-ĸB target gene expression and immunohistochemistry of p65 displayed a significant activation of NF-ĸB in mTORLEC mice, suggesting a functional importance of this pathway for the observed inflammatory phenotype. Taken together, we show an unexpected acceleration of liver metastases upon deletion of mTOR in LECs. Our results support the notion that non-malignant host cells can contribute to resistance against mTOR inhibitors and encourage testing whether anti-inflammatory drugs are able to improve the efficacy of mTOR inhibitors for cancer therapy. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Long Jiao
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany
| | - Roman Eickhoff
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany
| | - Antje Egners
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany
| | - Sandra Jumpertz
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany
| | - Johanna Roth
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany
| | - Merve Erdem
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany
| | - Andreas Kroh
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany
| | - Hans Duimel
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, Maastricht, The Netherlands
| | - Carmen López-Iglesias
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, Maastricht, The Netherlands
| | - Pilar Caro
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany
| | - Lara R Heij
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany.,Pathology, RWTH University Hospital, Aachen, Germany
| | - Maximilian Schmeding
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany
| | | | - Ulf P Neumann
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany.,ESCAM - European Surgery Center Aachen Maastricht, Aachen, Germany.,ESCAM - European Surgery Center Aachen Maastricht, Maastricht, The Netherlands.,Department of Surgery, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Thorsten Cramer
- Department of General, Visceral- and Transplantation Surgery, RWTH University Hospital, Aachen, Germany.,ESCAM - European Surgery Center Aachen Maastricht, Aachen, Germany.,NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
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10
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Verhaegh P, Wisse E, de Munck T, Greve JW, Verheij J, Riedl R, Duimel H, Masclee A, Jonkers D, Koek G. Electron microscopic observations in perfusion-fixed human non-alcoholic fatty liver disease biopsies. Pathology 2020; 53:220-228. [PMID: 33143903 DOI: 10.1016/j.pathol.2020.07.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 07/23/2020] [Accepted: 07/29/2020] [Indexed: 12/19/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a widespread liver disease in Western society, but its multifactorial pathogenesis is not yet fully understood. Ultrastructural analysis of liver sinusoidal endothelial cells (LSECs) in animal models and in vitro studies shows defenestration early in the course of NAFLD, promoting steatosis. LSECs and fenestrae are important in the transport of lipids across the sinusoids. However, human ultrastructural data, especially on LSECs and fenestrae, are scarce. This study aimed to explore the ultrastructural changes in perfusion type fixed liver biopsies of NAFLD patients with and without non-alcoholic steatohepatitis (NASH), with a special focus on LSECs and their fenestration. Liver biopsies from patients with NAFLD were fixed using two perfusion techniques, jet and injection fixation, for needle and wedge biopsies, respectively. Ultrastructural changes were studied using transmission electron microscopy. NASH was diagnosed by bright-field microscopy using the SAF score (steatosis, activity, fibrosis). Thirty-seven patients were included, of which 12 (32.4%) had NASH. Significantly less defenestration was found in NASH compared to noNASH samples (p=0.002). Other features, i.e., giant mitochondria and fenestrae size did not differ between groups. Furthermore, we described new structures, i.e., single cell steatonecrosis and inflammatory fat follicles (IFF) that were observed in both groups. Concluding, defenestration was more common in noNASH compared to NASH in human liver samples. Defenestration was not related to the degree of steatosis or fibrosis. We speculate that defenestration can be a protective mechanism in simple steatosis which is lacking in NASH.
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Affiliation(s)
- Pauline Verhaegh
- Department of Internal Medicine, Division Gastroenterology-Hepatology, Maastricht University Medical Center, Maastricht, the Netherlands; School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Maastricht, the Netherlands.
| | - Eddie Wisse
- Division of Nanoscopy, Maastricht Multimodal Molecular Imaging Institute, and Department of Internal Medicine/Hepatology, The University of Maastricht, Maastricht, the Netherlands
| | - Toon de Munck
- Department of Internal Medicine, Division Gastroenterology-Hepatology, Maastricht University Medical Center, Maastricht, the Netherlands; School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Maastricht, the Netherlands
| | - Jan Willem Greve
- Department of Surgery, Zuyderland MC, Heerlen, the Netherlands; Department of Gastro-Intestinal Surgery, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Joanne Verheij
- Department of Pathology, Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Robert Riedl
- Department of Pathology, Zuyderland MC, Heerlen, the Netherlands
| | - Hans Duimel
- Division of Nanoscopy, Maastricht Multimodal Molecular Imaging Institute, and Department of Internal Medicine/Hepatology, The University of Maastricht, Maastricht, the Netherlands
| | - Ad Masclee
- Department of Internal Medicine, Division Gastroenterology-Hepatology, Maastricht University Medical Center, Maastricht, the Netherlands; School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Maastricht, the Netherlands
| | - Daisy Jonkers
- School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Maastricht, the Netherlands
| | - Ger Koek
- Department of Internal Medicine, Division Gastroenterology-Hepatology, Maastricht University Medical Center, Maastricht, the Netherlands; School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Maastricht, the Netherlands; Department of Visceral and Transplantation Surgery, Klinikum RWTH, Aachen, Germany
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11
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Gemmink A, Daemen S, Kuijpers HJH, Schaart G, Duimel H, López-Iglesias C, van Zandvoort MAMJ, Knoops K, Hesselink MKC. Super-resolution microscopy localizes perilipin 5 at lipid droplet-mitochondria interaction sites and at lipid droplets juxtaposing to perilipin 2. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:1423-1432. [PMID: 30591149 DOI: 10.1016/j.bbalip.2018.08.016] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/06/2018] [Accepted: 08/29/2018] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Intramyocellular lipid droplets (LD) and their coat proteins PLIN2 and PLIN5 are involved in lipolysis, with a putative role for PLIN5 in mitochondrial tethering. Reportedly, these proteins co-localize and cover the surface of the LD. To provide the spatial basis for understanding how these proteins possess their distinct roles, we examined the precise location of PLIN2 and PLIN5 and explored PLIN5 presence at LD-mitochondria contact sites using Stimulated emission depletion (STED) microscopy and correlative light-electron microscopy (CLEM) in human skeletal muscle sections. METHODS LDs were stained by MDH together with combinations of mitochondrial proteins and PLINs. Subcellular distribution and co-localization of PLIN proteins and mitochondria was imaged by STED microscopy (Leica TCS SP8) and quantified using Pearson's correlation coefficients and intensity profile plots. CLEM was employed to examine the presence of PLIN5 on mitochondria-LD contact sites. RESULTS Both PLIN2 and PLIN5 localized to the LD in a dot-like, juxtaposed fashion rather than colocalizing and covering the entire LD. Both STED and CLEM revealed a high fraction of PLIN5 at the LD-mitochondria interface, but not at mitochondrial cristae, as suggested previously. CONCLUSION Using two super-resolution imaging approaches, this is the first study to show that in sections of human skeletal muscle PLIN2 and PLIN5 localize to the LD at distinct sites, with abundance of PLIN5 at LD-mitochondria tethering sites. This novel spatial information uncovers that PLIN proteins do not serve as lipolytic barriers but rather are docking sites for proteins facilitating selective lipase access under a variety of lipolytic conditions.
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Affiliation(s)
- Anne Gemmink
- Department of Nutrition and Movement Sciences, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht, the Netherlands
| | - Sabine Daemen
- Department of Nutrition and Movement Sciences, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht, the Netherlands
| | - Helma J H Kuijpers
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Gert Schaart
- Department of Nutrition and Movement Sciences, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht, the Netherlands
| | - Hans Duimel
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Carmen López-Iglesias
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Marc A M J van Zandvoort
- Department of Genetics & Cell Biology - Molecular Cell Biology, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; CARIM - Cardiovascular Research Institute Maastricht, Maastricht, the Netherlands; Institute for Molecular Cardiovascular Research IMCAR, Universitätsklinikum, Aachen, Pauwelstrasse 30, Aachen, Germany
| | - Kèvin Knoops
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Matthijs K C Hesselink
- Department of Nutrition and Movement Sciences, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht, the Netherlands.
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12
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Gomez AM, Stevens JAA, Mané-Damas M, Molenaar P, Duimel H, Verheyen F, Cossins J, Beeson D, De Baets MH, Losen M, Martinez-Martinez P. Silencing of Dok-7 in Adult Rat Muscle Increases Susceptibility to Passive Transfer Myasthenia Gravis. Am J Pathol 2017; 186:2559-68. [PMID: 27658713 DOI: 10.1016/j.ajpath.2016.05.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 04/30/2016] [Accepted: 05/19/2016] [Indexed: 11/17/2022]
Abstract
Myasthenia gravis (MG) is an autoimmune disease mediated by autoantibodies that target proteins at the neuromuscular junction, primarily the acetylcholine receptor (AChR) and the muscle-specific kinase. Because downstream of kinase 7 (Dok-7) is essential for the full activation of muscle-specific kinase and consequently for dense clustering of AChRs, we hypothesized that reduced levels of Dok-7 increase the susceptibility to passive transfer MG. To test this hypothesis, Dok-7 expression was reduced by transfecting shRNA-coding plasmids into the tibialis anterior muscle of adult rats by in vivo electroporation. Subclinical MG was subsequently induced with a low dose of anti-AChR monoclonal antibody 35. Neuromuscular transmission was significantly impaired in Dok-7-siRNA-electroporated legs compared with the contralateral control legs, which correlated with a reduction of AChR protein levels at the neuromuscular junction (approximately 25%) in Dok-7-siRNA-electroporated muscles, compared with contralateral control muscles. These results suggest that a reduced expression of Dok-7 may play a role in the susceptibility to passive transfer MG, by rendering AChR clusters less resistant to the autoantibody attack.
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Affiliation(s)
- Alejandro M Gomez
- Neuroimmunology Group, Division of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands.
| | - Jo A A Stevens
- Neuroimmunology Group, Division of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Marina Mané-Damas
- Neuroimmunology Group, Division of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Peter Molenaar
- Neuroimmunology Group, Division of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Hans Duimel
- Electron Microscopy Unit, Department of Molecular Cell Biology, Maastricht University, Maastricht, the Netherlands
| | - Fons Verheyen
- Electron Microscopy Unit, Department of Molecular Cell Biology, Maastricht University, Maastricht, the Netherlands
| | - Judith Cossins
- Neurosciences Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - David Beeson
- Neurosciences Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Marc H De Baets
- Neuroimmunology Group, Division of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Mario Losen
- Neuroimmunology Group, Division of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Pilar Martinez-Martinez
- Neuroimmunology Group, Division of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands.
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13
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Octavia Y, Kararigas G, de Boer M, Chrifi I, Kietadisorn R, Swinnen M, Duimel H, Verheyen FK, Brandt MM, Fliegner D, Cheng C, Janssens S, Duncker DJ, Moens AL. Folic acid reduces doxorubicin-induced cardiomyopathy by modulating endothelial nitric oxide synthase. J Cell Mol Med 2017; 21:3277-3287. [PMID: 28608983 PMCID: PMC5706529 DOI: 10.1111/jcmm.13231] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Accepted: 04/13/2017] [Indexed: 11/28/2022] Open
Abstract
The use of doxorubicin (DOXO) as a chemotherapeutic drug has been hampered by cardiotoxicity leading to cardiomyopathy and heart failure. Folic acid (FA) is a modulator of endothelial nitric oxide (NO) synthase (eNOS), which in turn is an important player in diseases associated with NO insufficiency or NOS dysregulation, such as pressure overload and myocardial infarction. However, the role of FA in DOXO‐induced cardiomyopathy is poorly understood. The aim of this study was to test the hypothesis that FA prevents DOXO‐induced cardiomyopathy by modulating eNOS and mitochondrial structure and function. Male C57BL/6 mice were randomized to a single dose of DOXO (20 mg/kg intraperitoneal) or sham. FA supplementation (10 mg/day per oral) was started 7 days before DOXO injection and continued thereafter. DOXO resulted in 70% mortality after 10 days, with the surviving mice demonstrating a 30% reduction in stroke volume compared with sham groups. Pre‐treatment with FA reduced mortality to 45% and improved stroke volume (both P < 0.05 versus DOXO). These effects of FA were underlain by blunting of DOXO‐induced cardiomyocyte atrophy, apoptosis, interstitial fibrosis and impairment of mitochondrial function. Mechanistically, pre‐treatment with FA prevented DOXO‐induced increases in superoxide anion production by reducing the eNOS monomer:dimer ratio and eNOS S‐glutathionylation, and attenuated DOXO‐induced decreases in superoxide dismutase, eNOS phosphorylation and NO production. Enhancing eNOS function by restoring its coupling and subsequently reducing oxidative stress with FA may be a novel therapeutic approach to attenuate DOXO‐induced cardiomyopathy.
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Affiliation(s)
- Yanti Octavia
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Department of Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Georgios Kararigas
- Institute of Gender in Medicine and Center for Cardiovascular Research, Charite University Hospital, Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), Berlin, Germany
| | - Martine de Boer
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Ihsan Chrifi
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Rinrada Kietadisorn
- Department of Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Melissa Swinnen
- Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Hans Duimel
- Electron Microscopy Unit, CRISP and Department of Molecular Cell Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Fons K Verheyen
- Electron Microscopy Unit, CRISP and Department of Molecular Cell Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Maarten M Brandt
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Daniela Fliegner
- Institute of Gender in Medicine and Center for Cardiovascular Research, Charite University Hospital, Berlin, Germany
| | - Caroline Cheng
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Stefan Janssens
- Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Dirk J Duncker
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - An L Moens
- Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Department of Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands
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14
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Andre E, Yaniz-Galende E, Hamilton C, Dusting GJ, Hellen N, Poulet CE, Diez Cunado M, Smits AM, Lowe V, Eckardt D, Du Pre B, Sanz Ruiz R, Moerkamp AT, Tribulova N, Smani T, Liskova YV, Greco S, Guzzolino E, Franco D, Lozano-Velasco E, Knorr M, Pavoine C, Bukowska A, Van Linthout S, Miteva K, Sulzgruber P, Latet SC, Portnychenko A, Cannavo A, Kamilova U, Sagach VF, Santin Y, Octavia Y, Haller PM, Octavia Y, Rubies C, Dei Zotti F, Wong KHK, Gonzalez Miqueo A, Kruithof BPT, Kadur Nagaraju C, Shaposhnikova Y, Songia P, Lindner D, Wilson C, Benzoni P, Fabbri A, Campostrini G, Jorge E, Casini S, Mengarelli I, Nikolov A, Bublikov DS, Kheloufi M, Rubies C, Walker RE, Van Dijk RA, Posthuma JJ, Dumitriu IE, Karshovska E, Sakic A, Alexandru N, Martin-Lorenzo M, Molica F, Taylor RF, Mcarthur L, Crocini C, Matsuyama TA, Mazzoni L, Lin WK, Owen TJ, Scigliano M, Sheehan A, Bezerra Gurgel AR, Bromage DI, Kiss A, Ikeda G, Pickard JMJ, Wirth G, Casos K, Khudiakov A, Nistal JF, Ferrantini C, Park SJ, Di Maggio S, Gentile F, Dini L, Buyandelger B, Larrasa-Alonso J, Schirmer I, Chin SH, Cimiotti D, Martini H, Hohensinner PJ, Garabito M, Zeni F, Licholai S, De Bortoli M, Sivitskaya L, Viczenczova C, Rainer PP, Smith LE, Suna G, Gambardella J, Cozma A, De Gonzalo Calvo D, Scoditti E, Clark BJ, Mansfield C, Eckardt D, Gomez L, Llucia-Valldeperas A, De Pauw A, Porporato P, Bouzin C, Draoui N, Sonveaux P, Balligand JL, Mougenot N, Formicola L, Nadaud S, Dierick F, Hajjar RJ, Marazzi G, Sassoon D, Hulot JS, Zamora VR, Burton FL, Macquaide N, Smith GL, Hernandez D, Sivakumaran P, Millard R, Wong RCB, Pebay A, Shepherd RK, Lim SY, Owen T, Jabbour RJ, Kloc M, Kodagoda T, Denning C, Harding SE, Ramos S, Terracciano C, Gorelik J, Wei K, Bushway P, Ruiz-Lozano P, Mercola M, Moerkamp AT, Vegh AMD, Dronkers E, Lodder K, Van Herwaarden T, Goumans MJ, Pellet-Many C, Zachary I, Noack K, Bosio A, Feyen DAM, Demkes EJ, Dierickx PJ, Doevendans PA, Vos MA, Van Veen AAB, Van Laake LW, Fernandez Santos ME, Suarez Sancho S, Fuentes Arroyo L, Plasencia Martin V, Velasco Sevillano P, Casado Plasencia A, Climent AM, Guillem M, Atienza Fernandez F, Fernandez-Aviles F, Dingenouts CKE, Lodder K, Kruithof BPT, Van Herwaarden T, Vegh AMD, Goumans MJ, Smits AM, Knezl V, Szeiffova Bacova B, Egan Benova T, Viczenczova C, Goncalvesova E, Slezak J, Calderon-Sanchez E, Diaz I, Ordonez A, Salikova SP, Zaccagnini G, Voellenkle C, Sadeghi I, Maimone B, Castelvecchio S, Gaetano C, Menicanti L, Martelli F, Hatcher C, D'aurizio R, Groth M, Baugmart M, Mercatanti A, Russo F, Mariani L, Magliaro C, Pitto L, Lozano-Velasco E, Jodar-Garcia A, Galiano-Torres J, Lopez-Navarrete I, Aranega A, Wagensteen R, Quesada A, Aranega A, Franco D, Finger S, Karbach S, Kossmann S, Muenzel T, Wenzel P, Keck M, Mougenot N, Favier S, Fuand A, Atassi F, Barbier C, Lompre AM, Hulot JS, Nikonova Y, Pluteanu F, Kockskaemper J, Chilukoti RK, Wolke C, Lendeckel U, Gardemann A, Goette A, Miteva K, Pappritz K, Mueller I, El-Shafeey M, Ringe J, Tschoepe C, Pappritz K, El-Shafeey M, Ringe J, Tschoepe C, Van Linthout S, Koller L, Richter B, Blum S, Koprak M, Huelsmann M, Pacher R, Goliasch G, Wojta J, Niessner A, Van Herck PL, Claeys MJ, Haine SE, Lenders GD, Miljoen HP, Segers VF, Vandendriescche TR, Hoymans VY, Vrints CJ, Lapikova-Bryhinska T, Gurianova V, Portnichenko H, Vasylenko M, Zapara Y, Portnichenko V, Liccardo D, Lymperopoulos A, Santangelo M, Leosco D, Koch WJ, Ferrara N, Rengo G, Alieva T, Rasulova Z, Masharipova D, Dorofeyeva NA, Drachuk KO, Sicard P, Yucel Y, Dutaur M, Vindis C, Parini A, Mialet-Perez J, Van Deel ED, De Boer M, De Waard MC, Duncker DJ, Nagel F, Inci M, Santer D, Hallstroem S, Podesser BK, Kararigas G, De Boer M, Kietadisorn R, Swinnen M, Duimel H, Verheyen F, Chrifi I, Brandt MM, Cheng C, Janssens S, Moens AL, Duncker DJ, Batlle M, Dantas AP, Sanz M, Sitges M, Mont L, Guasch E, Lobysheva I, Beauloye C, Balligand JL, Vanhoutte PM, Tang EHC, Beaumont J, Lopez B, Ravassa S, Hermida N, Valencia F, Gomez-Doblas JJ, San Jose G, De Teresa E, Diez J, Van De Merbel AF, Kruithof-De Julio M, Goumans MJ, Claus P, Dries E, Angelo Singh A, Vermeulen K, Roderick HL, Sipido KR, Driesen RB, Ilchenko I, Bobronnikova L, Myasoedova V, Alamanni F, Tremoli E, Poggio P, Becher PM, Gotzhein F, Klingel K, Blankenberg S, Westermann D, Zi M, Cartwright E, Campostrini G, Bonzanni M, Milanesi R, Bucchi A, Baruscotti M, Difrancesco D, Barbuti A, Fantini M, Wilders R, Severi S, Benzoni P, Dell' Era P, Serzanti M, Olesen MS, Muneretto C, Bisleri G, Difrancesco D, Baruscotti M, Bucchi A, Barbuti A, Amoros-Figueras G, Raga S, Campos B, Alonso-Martin C, Rodriguez-Font E, Vinolas X, Cinca J, Guerra JM, Mengarelli I, Schumacher CA, Veldkamp MW, Verkerk AO, Remme CA, Veerman C, Guan K, Stauske M, Tan H, Barc J, Wilde A, Verkerk A, Bezzina C, Tsinlikov I, Tsinlikova I, Nicoloff G, Blazhev A, Garev A, Andrienko AV, Lychev VG, Vorobova EN, Anchugina DA, Vion AC, Hammoutene A, Poisson J, Dupont N, Souyri M, Tedgui A, Codogno P, Boulanger CM, Rautou PE, Dantas AP, Batlle M, Guasch E, Torres M, Montserrat JM, Almendros I, Mont L, Austin CA, Holt CM, Rijs K, Wezel A, Hamming JF, Kolodgie FD, Virmani R, Schaapherder AF, Lindeman JHN, Posma JJN, Van Oerle R, Spronk HMH, Ten Cate H, Dinkla S, Kaski JC, Schober A, Chaabane C, Ambartsumian N, Grigorian M, Bochaton-Piallat ML, Dragan E, Andrei E, Niculescu L, Georgescu A, Gonzalez-Calero L, Maroto AS, Martinez PJ, Heredero A, Aldamiz-Echevarria G, Vivanco F, Alvarez-Llamas G, Meens MJ, Pelli G, Foglia B, Scemes E, Kwak BR, Caldwell JL, Eisner DA, Dibb KM, Trafford AW, Chilton L, Smith GL, Nicklin SA, Coppini R, Ferrantini C, Yan P, Loew LM, Poggesi C, Cerbai E, Pavone FS, Sacconi L, Tanaka H, Ishibashi-Ueda H, Takamatsu T, Coppini R, Ferrantini C, Gentile F, Pioner JM, Santini L, Sartiani L, Bargelli V, Poggesi C, Mugelli A, Cerbai E, Maciejewska M, Bolton EL, Wang Y, O'brien F, Ruas M, Lei M, Sitsapesan R, Galione A, Terrar DA, Smith JG, Garcia D, Barriales-Villa R, Monserrat L, Harding SE, Denning C, Marston SB, Watson S, Tkach S, Faggian G, Terracciano CM, Perbellini F, Eiros Zamora J, Papadaki M, Messer A, Marston S, Gould I, Johnston A, Dunne M, Smith G, Kemi OJ, Pillai M, Davidson SM, Yellon DM, Tratsiakovich Y, Jang J, Gonon AT, Pernow J, Matoba T, Koga J, Egashira K, Burke N, Davidson SM, Yellon DM, Korpisalo P, Hakkarainen H, Laidinen S, Yla-Herttuala S, Ferrer-Curriu G, Perez M, Permanyer E, Blasco-Lucas A, Gracia JM, Castro MA, Barquinero J, Galinanes M, Kostina D, Kostareva A, Malashicheva A, Merino D, Ruiz L, Gomez J, Juarez C, Gil A, Garcia R, Hurle MA, Coppini R, Pioner JM, Gentile F, Mazzoni L, Rossi A, Tesi C, Belardinelli L, Olivotto I, Cerbai E, Mugelli A, Poggesi C, Eun-Ji EJ, Lim BK, Choi DJ, Milano G, Bertolotti M, De Marchis F, Zollo F, Sommariva E, Capogrossi MC, Pompilio G, Bianchi ME, Raucci A, Pioner JM, Coppini R, Scellini B, Tardiff J, Tesi C, Poggesi C, Ferrantini C, Mazzoni L, Sartiani L, Coppini R, Diolaiuti L, Ferrari P, Cerbai E, Mugelli A, Mansfield C, Luther P, Knoell R, Villalba M, Sanchez-Cabo F, Lopez-Olaneta MM, Ortiz-Sanchez P, Garcia-Pavia P, Lara-Pezzi E, Klauke B, Gerdes D, Schulz U, Gummert J, Milting H, Wake E, Kocsis-Fodor G, Brack KE, Ng GA, Kostareva A, Smolina N, Majchrzak M, Moehner D, Wies A, Milting H, Stehle R, Pfitzer G, Muegge A, Jaquet K, Maggiorani D, Lefevre L, Dutaur M, Mialet-Perez J, Parini A, Cussac D, Douin-Echinard V, Ebenbauer B, Kaun C, Prager M, Wojta J, Rega-Kaun G, Costa G, Onetti Y, Jimenez-Altayo F, Vila E, Dantas AP, Milano G, Bertolotti M, Scopece A, Piacentini L, Bianchi ME, Capogrossi MC, Pompilio G, Colombo G, Raucci A, Blaz M, Kapelak B, Sanak M, Bauce B, Calore C, Lorenzon A, Calore M, Poloni G, Mazzotti E, Rigato I, Daliento L, Basso C, Thiene G, Melacini P, Corrado D, Rampazzo A, Danilenko NG, Vaikhanskaya TG, Davydenko OG, Szeiffova Bacova B, Kura B, Egan Benova T, Yin CH, Kukreja R, Slezak J, Tribulova N, Lee DI, Sorge M, Glabe C, Paolocci N, Guarnieri C, Tomaselli GF, Kass DA, Van Eyk JE, Agnetti G, Cordwell SJ, White MY, Wojakowski W, Lynch M, Barallobre-Barreiro J, Yin X, Mayr U, White S, Jahingiri M, Hill J, Mayr M, Sorriento D, Ciccarelli M, Fiordelisi A, Campiglia P, Trimarco B, Iaccarino G, Sitar Taut AV, Schiau S, Orasan O, Halloumi W, Negrean V, Zdrenghea D, Pop D, Van Der Meer RW, Rijzewijk LJ, Smit JWA, Revuelta-Lopez E, Nasarre L, Escola-Gil JC, Lamb HJ, Llorente-Cortes V, Pellegrino M, Massaro M, Carluccio MA, Calabriso N, Wabitsch M, Storelli C, De Caterina R, Church SJ, Callagy S, Begley P, Kureishy N, Mcharg S, Bishop PN, Unwin RD, Cooper GJS, Mawad D, Perbellini F, Tonkin J, Bello SO, Simonotto JD, Lyon AR, Stevens MM, Terracciano CM, Harding SE, Kernbach M, Czichowski V, Bosio A, Fuentes L, Hernandez-Redondo I, Guillem MS, Fernandez ME, Sanz R, Atienza F, Climent AM, Fernandez-Aviles F, Soler-Botija C, Prat-Vidal C, Galvez-Monton C, Roura S, Perea-Gil I, Bragos R, Bayes-Genis A. Poster session 1Cell growth, differentiation and stem cells - Heart72Understanding the metabolism of cardiac progenitor cells: a first step towards controlling their proliferation and differentiation?73Expression of pw1/peg3 identifies a new cardiac adult stem cell population involved in post-myocardial infarction remodeling74Long-term stimulation of iPS-derived cardiomyocytes using optogenetic techniques to promote phenotypic changes in E-C coupling75Benefits of electrical stimulation on differentiation and maturation of cardiomyocytes from human induced pluripotent stem cells76Constitutive beta-adrenoceptor-mediated cAMP production controls spontaneous automaticity of human induced pluripotent stem cell-derived cardiomyocytes77Formation and stability of T-tubules in cardiomyocytes78Identification of miRNAs promoting human cardiomyocyte proliferation by regulating Hippo pathway79A direct comparison of foetal to adult epicardial cell activation reveals distinct differences relevant for the post-injury response80Role of neuropilins in zebrafish heart regeneration81Highly efficient immunomagnetic purification of cardiomyocytes derived from human pluripotent stem cells82Cardiac progenitor cells posses a molecular circadian clock and display large 24-hour oscillations in proliferation and stress tolerance83Influence of sirolimus and everolimus on bone marrow-derived mesenchymal stem cell biology84Endoglin is important for epicardial behaviour following cardiac injuryCell death and apoptosis - Heart87Ultrastructural alterations reflecting Ca2+ handling and cell-to-cell coupling disorders precede occurrence of severe arrhythmias in intact animal heart88Urocortin-1 promotes cardioprotection through ERK1/2 and EPAC pathways: role in apoptosis and necrosis89Expression p38 MAPK and Cas-3 in myocardium LV of rats with experimental heart failure at melatonin and enalapril introductionTranscriptional control and RNA species - Heart92Accumulation of beta-amyloid 1-40 in HF patients: the role of lncRNA BACE1-AS93Role of miR-182 in zebrafish and mouse models of Holt-Oram syndrome94Mir-27 distinctly regulates muscle-enriched transcription factors and growth factors in cardiac and skeletal muscle cells95AF risk factors impair PITX2 expression leading to Wnt-microRNA-ion channel remodelingCytokines and cellular inflammation - Heart98Post-infarct survival depends on the interplay of monocytes, neutrophils and interferon gamma in a mouse model of myocardial Infarction99Inflammatory cd11b/c cells play a protective role in compensated cardiac hypertrophy by promoting an orai3-related pro-survival signal100Anti-inflammatory effects of endothelin receptor blockade in the atrial tissue of spontaneously hypertensive rats101Mesenchymal stromal cells reduce NLRP3 inflammasome activity in Coxsackievirus B3-induced myocarditis102Mesenchymal stromal cells modulate monocytes trafficking in Coxsackievirus B3-induced myocarditis103The impact of regulatory T lymphocytes on long-term mortality in patients with chronic heart failure104Temporal dynamics of dendritic cells after ST-elevation myocardial infarction relate with improvement of myocardial functionGrowth factors and neurohormones - Heart107Preconditioning of hypertrophied heart: miR-1 and IGF-1 crosstalk108Modulation of catecholamine secretion from human adrenal chromaffin cells by manipulation of G protein-coupled receptor kinase-2 activity109Evaluation of cyclic adenosin-3,5- monophosphate and neurohormones in patients with chronic heart failureNitric oxide and reactive oxygen species - Heart112Hydrogen sulfide donor inhibits oxidative and nitrosative stress, cardiohemodynamics disturbances and restores cNOS coupling in old rats113Role and mechanisms of action of aldehydes produced by monoamine oxidase A in cardiomyocyte death and heart failure114Exercise training has contrasting effects in myocardial infarction and pressure-overload due to different endothelial nitric oxide synthase regulation115S-Nitroso Human Serum Albumin dose-dependently leads to vasodilation and alters reactive hyperaemia in coronary arteries of an isolated mouse heart model116Modulating endothelial nitric oxide synthase with folic acid attenuates doxorubicin-induced cardiomyopathy119Effects of long-term very high intensity exercise on aortic structure and function in an animal model120Electron paramagnetic resonance spectroscopy quantification of nitrosylated hemoglobin (HbNO) as an index of vascular nitric oxide bioavailability in vivo121Deletion of repressor activator protein 1 impairs acetylcholine-induced relaxation due to production of reactive oxygen speciesExtracellular matrix and fibrosis - Heart124MicroRNA-19b is associated with myocardial collagen cross-linking in patients with severe aortic stenosis. Potential usefulness as a circulating biomarker125A new ex vivo model to study cardiac fibrosis126Heterogeneity of fibrosis and fibroblast differentiation in the left ventricle after myocardial infarction127Effect of carbohydrate metabolism degree compensation to the level of galectin-3 changes in hypertensive patients with chronic heart failure and type 2 diabetes mellitus128Statin paradox in association with calcification of bicuspid aortic valve interstitial cells129Cardiac function remains impaired despite reversible cardiac fibrosis after healed experimental viral myocarditisIon channels, ion exchangers and cellular electrophysiology - Heart132Identifying a novel role for PMCA1 (Atp2b1) in heart rhythm instability133Mutations of the caveolin-3 gene as a predisposing factor for cardiac arrhythmias134The human sinoatrial node action potential: time for a computational model135iPSC-derived cardiomyocytes as a model to dissect ion current alterations of genetic atrial fibrillation136Postextrasystolic potentiation in healthy and diseased hearts: effects of the site of origin and coupling interval of the preceding extrasystole137Absence of Nav1.8-based (late) sodium current in rabbit cardiomyocytes and human iPSC-CMs138hiPSC-derived cardiomyocytes from Brugada Syndrome patients without identified mutations do not exhibit cellular electrophysiological abnormalitiesMicrocirculation141Atherogenic indices, collagen type IV turnover and the development of microvascular complications- study in diabetics with arterial hypertension142Changes in the microvasculature and blood viscosity in women with rheumatoid arthritis, hypercholesterolemia and hypertensionAtherosclerosis145Shear stress regulates endothelial autophagy: consequences on endothelial senescence and atherogenesis146Obstructive sleep apnea causes aortic remodeling in a chronic murine model147Aortic perivascular adipose tissue displays an aged phenotype in early and late atherosclerosis in ApoE-/- mice148A systematic evaluation of the cellular innate immune response during the process of human atherosclerosis149Inhibition of Coagulation factor Xa increases plaque stability and attenuates the onset and progression of atherosclerotic plaque in apolipoprotein e-deficient mice150Regulatory CD4+ T cells from patients with atherosclerosis display pro-inflammatory skewing and enhanced suppression function151Hypoxia-inducible factor (HIF)-1alpha regulates macrophage energy metabolism by mediating miRNAs152Extracellular S100A4 is a key player of smooth muscle cell phenotypic transition: implications in atherosclerosis153Microparticles of healthy origins improve atherosclerosis-associated endothelial progenitor cell dysfunction via microRNA transfer154Arterial remodeling and metabolism impairment in early atherosclerosis155Role of pannexin1 in atherosclerotic plaque formationCalcium fluxes and excitation-contraction coupling158Amphiphysin II induces tubule formation in cardiac cells159Interleukin 1 beta regulation of connexin 43 in cardiac fibroblasts and the effects of adult cardiac myocyte:fibroblast co-culture on myocyte contraction160T-tubular electrical defects contribute to blunted beta-adrenergic response in heart failure161Beat-to-beat variability of intracellular Ca2+ dynamics of Purkinje cells in the infarct border zone of the mouse heart revealed by rapid-scanning confocal microscopy162The efficacy of late sodium current blockers in hypertrophic cardiomyopathy is dependent on genotype: a study on transgenic mouse models with different mutations163Synthesis of cADPR and NAADP by intracellular CD38 in heart: role in inotropic and arrhythmogenic effects of beta-adrenoceptor signalingContractile apparatus166Towards an engineered heart tissue model of HCM using hiPSC expressing the ACTC E99K mutation167Diastolic mechanical load delays structural and functional deterioration of ultrathin adult heart slices in culture168Structural investigation of the cardiac troponin complex by molecular dynamics169Exercise training restores myocardial and oxidative skeletal muscle function from myocardial infarction heart failure ratsOxygen sensing, ischaemia and reperfusion172A novel antibody specific to full-length stromal derived factor-1 alpha reveals that remote conditioning induces its cleavage by endothelial dipeptidyl peptidase 4173Attenuation of myocardial and vascular arginase activity by vagal nerve stimulation via a mechanism involving alpha-7 nicotinic receptor during cardiac ischemia and reperfusion174Novel nanoparticle-mediated medicine for myocardial ischemia-reperfusion injury simultaneously targeting mitochondrial injury and myocardial inflammation175Acetylcholine plays a key role in myocardial ischaemic preconditioning via recruitment of intrinsic cardiac ganglia176The role of nitric oxide and VEGFR-2 signaling in post ischemic revascularization and muscle recovery in aged hypercholesterolemic mice177Efficacy of ischemic preconditioning to protect the human myocardium: the role of clinical conditions and treatmentsCardiomyopathies and fibrosis180Plakophilin-2 haploinsufficiency leads to impaired canonical Wnt signaling in ARVC patient181Improved technique for customized, easier, safer and more reliable transverse aortic arch banding and debanding in mice as a model of pressure overload hypertrophy182Late sodium current inhibitors for the treatment of inducible obstruction and diastolic dysfunction in hypertrophic cardiomyopathy: a study on human myocardium183Angiotensin II receptor antagonist fimasartan has protective role of left ventricular fibrosis and remodeling in the rat ischemic heart184Role of High-Mobility Group Box 1 (HMGB1) redox state on cardiac fibroblasts activities and heart function after myocardial infarction185Atrial remodeling in hypertrophic cardiomyopathy: insights from mouse models carrying different mutations in cTnT186Electrophysiological abnormalities in ventricular cardiomyocytes from a Maine Coon cat with hypertrophic cardiomyopathy: effects of ranolazine187ZBTB17 is a novel cardiomyopathy candidate gene and regulates autophagy in the heart188Inhibition of SRSF4 in cardiomyocytes induces left ventricular hypertrophy189Molecular characterization of a novel cardiomyopathy related desmin frame shift mutation190Autonomic characterisation of electro-mechanical remodeling in an in-vitro leporine model of heart failure191Modulation of Ca2+-regulatory function by three novel mutations in TNNI3 associated with severe infant restrictive cardiomyopathyAging194The aging impact on cardiac mesenchymal like stromal cells (S+P+)195Reversal of premature aging markers after bariatric surgery196Sex-associated differences in vascular remodeling during aging: role of renin-angiotensin system197Role of the receptor for advanced glycation end-products (RAGE) in age dependent left ventricle dysfunctionsGenetics and epigenetics200hsa-miR-21-5p as a key factor in aortic remodeling during aneurysm formation201Co-inheritance of mutations associated with arrhythmogenic and hypertrophic cardiomyopathy in two Italian families202Lamin a/c hot spot codon 190: form various amino acid substitutions to clinical effects203Treatment with aspirin and atorvastatin attenuate cardiac injury induced by rat chest irradiation: Implication of myocardial miR-1, miR-21, connexin-43 and PKCGenomics, proteomics, metabolomics, lipidomics and glycomics206Differential phosphorylation of desmin at serines 27 and 31 drives the accumulation of preamyloid oligomers in heart failure207Potential role of kinase Akt2 in the reduced recovery of type 2 diabetic hearts subjected to ischemia / reperfusion injury208A proteomics comparison of extracellular matrix remodelling in porcine coronary arteries upon stent implantationMetabolism, diabetes mellitus and obesity211Targeting grk2 as therapeutic strategy for cancer associated to diabetes212Effects of salbutamol on large arterial stiffness in patients with metabolic syndrome213Circulating microRNA-1 and microRNA-133a: potential biomarkers of myocardial steatosis in type 2 diabetes mellitus214Anti-inflammatory nutrigenomic effects of hydroxytyrosol in human adipocytes - protective mechanisms of mediterranean diets in obesity-related inflammation215Alterations in the metal content of different cardiac regions within a rat model of diabetic cardiomyopathyTissue engineering218A novel conductive patch for application in cardiac tissue engineering219Establishment of a simplified and improved workflow from neonatal heart dissociation to cardiomyocyte purification and characterization220Effects of flexible substrate on cardiomyocytes cell culture221Mechanical stretching on cardiac adipose progenitors upregulates sarcomere-related genes. Cardiovasc Res 2016. [DOI: 10.1093/cvr/cvw135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Vreuls C, Driessen A, Olde Damink S, Koek G, Duimel H, van den Broek M, Dejong C, Braet F, Wisse E. Sinusoidal obstruction syndrome (SOS): A light and electron microscopy study in human liver. Micron 2016; 84:17-22. [DOI: 10.1016/j.micron.2016.02.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 01/25/2016] [Accepted: 02/09/2016] [Indexed: 11/25/2022]
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van Hoof M, Wigren S, Duimel H, Savelkoul PHM, Flynn M, Stokroos RJ. Can the Hydroxyapatite-Coated Skin-Penetrating Abutment for Bone Conduction Hearing Implants Integrate with the Surrounding Skin? Front Surg 2015; 2:45. [PMID: 26442276 PMCID: PMC4568398 DOI: 10.3389/fsurg.2015.00045] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 08/21/2015] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION Percutaneous implants, such as bone conduction hearing implants, suffer from complications that include inflammation of the surrounding skin. A sealed skin-abutment interface can prevent the ingress of bacteria, which should reduce the occurrence of peri-abutment dermatitis. It was hypothesized that a hydroxyapatite (HA)-coated abutment in conjunction with soft tissue preservation surgery should enable integration with the adjacent skin. Previous research has confirmed that integration is never achieved with as-machined titanium abutments. Here, we investigate, in vivo, if skin integration is achievable in patients using a HA-coated abutment. MATERIALS AND METHODS One titanium abutment (control) and one HA-coated abutment (case) together with the surrounding skin were surgically retrieved from two patients who had a medical indication for this procedure. Histological sections of the skin were investigated using light microscopy. The abutment was qualitatively analyzed using scanning electron microscopy. RESULTS The titanium abutment only had a partial and thin layer of attached amorphous biological material. The HA-coated abutment was almost fully covered by a pronounced thick layer of organized skin, composed of different interconnected structural layers. CONCLUSION Proof-of-principle evidence that the HA-coated abutment can achieve integration with the surrounding skin was presented for the first time.
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Affiliation(s)
- Marc van Hoof
- Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center , Maastricht , Netherlands
| | - Stina Wigren
- Cochlear Bone Anchored Solutions AB , Mölnlycke , Sweden
| | - Hans Duimel
- Institute of Nanoscopy, Maastricht University Medical Center , Maastricht , Netherlands
| | - Paul H M Savelkoul
- Department of Medical Microbiology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center , Maastricht , Netherlands ; Department of Medical Microbiology and Infection Control, VU University Medical Center , Amsterdam , Netherlands
| | - Mark Flynn
- Cochlear Bone Anchored Solutions AB , Mölnlycke , Sweden
| | - Robert Jan Stokroos
- Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center , Maastricht , Netherlands
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Gomez AM, Willcox N, Vrolix K, Hummel J, Nogales-Gadea G, Saxena A, Duimel H, Verheyen F, Molenaar PC, Buurman WA, De Baets MH, Martinez-Martinez P, Losen M. Proteasome inhibition with bortezomib depletes plasma cells and specific autoantibody production in primary thymic cell cultures from early-onset myasthenia gravis patients. J Immunol 2014; 193:1055-1063. [PMID: 24973445 DOI: 10.4049/jimmunol.1301555] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Bortezomib is a potent inhibitor of proteasomes currently used to eliminate malignant plasma cells in multiple myeloma patients. It is also effective in depleting both alloreactive plasma cells in acute Ab-mediated transplant rejection and their autoreactive counterparts in animal models of lupus and myasthenia gravis (MG). In this study, we demonstrate that bortezomib at 10 nM or higher concentrations killed long-lived plasma cells in cultured thymus cells from nine early-onset MG patients and consistently halted their spontaneous production not only of autoantibodies against the acetylcholine receptor but also of total IgG. Surprisingly, lenalidomide and dexamethasone had little effect on plasma cells. After bortezomib treatment, they showed ultrastructural changes characteristic of endoplasmic reticulum stress after 8 h and were no longer detectable at 24 h. Bortezomib therefore appears promising for treating MG and possibly other Ab-mediated autoimmune or allergic disorders, especially when given in short courses at modest doses before the standard immunosuppressive drugs have taken effect.
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Affiliation(s)
- Alejandro M Gomez
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Nick Willcox
- Department of Clinical Neurology, University of Oxford, UK
| | - Kathleen Vrolix
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Jonas Hummel
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Gisela Nogales-Gadea
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands.,Neuromuscular Diseases Unit, Institut de Recerca del Hospital de la Santa Creu i Sant Pau, Universitat Autónoma de Barcelona, Barcelona, Spain
| | - Abhishek Saxena
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Hans Duimel
- ELMI Unit-CRISP, Department of Molecular Cell Biology, Maastricht University, Maastricht, the Netherlands
| | - Fons Verheyen
- ELMI Unit-CRISP, Department of Molecular Cell Biology, Maastricht University, Maastricht, the Netherlands
| | - Peter C Molenaar
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Wim A Buurman
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Marc H De Baets
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Pilar Martinez-Martinez
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Mario Losen
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
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Vreuls C, Wisse E, Duimel H, Stevens K, Verheyen F, Braet F, Driessen A, Koek G. Jet-fixation: a novel method to improve microscopy of human liver needle biopsies. Hepatology 2014; 59:737-9. [PMID: 23729406 DOI: 10.1002/hep.26532] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 05/03/2013] [Accepted: 05/10/2013] [Indexed: 12/17/2022]
Affiliation(s)
- Celien Vreuls
- Department of Pathology, Maastricht University Medical Centre, Maastricht, The Netherlands
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Gomez A, Willcox N, Vrolix K, Hummel J, Duimel H, Verheyen F, Molenaar P, Buurman W, Martinez-Martinez P, De Baets M, Losen M. Proteasome inhibition with bortezomib depletes plasma cells and autoantibody production in primary thymic cell cultures from early-onset myasthenia gravis patients (P5146). The Journal of Immunology 2013. [DOI: 10.4049/jimmunol.190.supp.68.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
In the autoimmune disease myasthenia gravis (MG), autoantibodies against the muscle AChR are mainly produced by both short- and long-lived plasma cells, which are resistant to standard immunosuppressive drugs (i.e. glucocorticoids). A novel therapy to eliminate plasma cells is the proteasome inhibitor bortezomib, which is used to treat patients with multiple myeloma (MM, a plasma cell malignancy). Previously, we demonstrated that bortezomib also reduced autoantibody titers in an animal model of MG (Gomez, A. M. J. Immunol. 2011). The thymus of MG patients is frequently enriched in germinal centers and contains plasma cells that produce autoantibodies in vitro, even after irradiation (which depletes B and T lymphocytes). We studied the in vitro effects of bortezomib in cultured thymus cells from MG patients undergoing therapeutic thymectomy. Treatment with a single dose of bortezomib blocked the production of these pathogenic autoantibodies, reduced the total IgG levels and eliminated plasma cells. Ultrastructural signs of apoptosis were detected in plasma cells as early as 8 h after addition of bortezomib; at 24 h, no plasma cells could be detected. Moreover, we demonstrated that the minimum concentration of bortezomib that eliminates plasma cells in vitro is 60-fold lower than the peak concentration found in MM patients treated with bortezomib, suggesting that low doses might be effective for eliminating plasma cells in patients with antibody-mediated autoimmune diseases.
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Affiliation(s)
- Alejandro Gomez
- 1Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Nick Willcox
- 2Clinical Neurology, University of Oxford, Oxford, United Kingdom
| | - Kathleen Vrolix
- 1Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Jonas Hummel
- 1Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Hans Duimel
- 3Electron Microscopy, Maastricht University, Maastricht, Netherlands
| | - Fons Verheyen
- 3Electron Microscopy, Maastricht University, Maastricht, Netherlands
| | - Peter Molenaar
- 1Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Wim Buurman
- 1Neuroscience, Maastricht University, Maastricht, Netherlands
| | | | - Marc De Baets
- 1Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Mario Losen
- 1Neuroscience, Maastricht University, Maastricht, Netherlands
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Gomez AM, Vrolix K, Martínez-Martínez P, Molenaar PC, Phernambucq M, van der Esch E, Duimel H, Verheyen F, Voll RE, Manz RA, De Baets MH, Losen M. Proteasome inhibition with bortezomib depletes plasma cells and autoantibodies in experimental autoimmune myasthenia gravis. J Immunol 2011; 186:2503-13. [PMID: 21239719 DOI: 10.4049/jimmunol.1002539] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Bortezomib, an inhibitor of proteasomes, has been reported to reduce autoantibody titers and to improve clinical condition in mice suffering from lupus-like disease. Bortezomib depletes both short- and long-lived plasma cells; the latter normally survive the standard immunosuppressant treatments targeting T and B cells. These findings encouraged us to test whether bortezomib is effective for alleviating the symptoms in the experimental autoimmune myasthenia gravis (EAMG) model for myasthenia gravis, a disease that is characterized by autoantibodies against the acetylcholine receptor (AChR) of skeletal muscle. Lewis rats were immunized with saline (control, n = 36) or Torpedo AChR (EAMG, n = 54) in CFA in the first week of an experimental period of 8 wk. After immunization, rats received twice a week s.c. injections of bortezomib (0.2 mg/kg in saline) or saline injections. Bortezomib induced apoptosis in bone marrow cells and reduced the amount of plasma cells in the bone marrow by up to 81%. In the EAMG animals, bortezomib efficiently reduced the rise of anti-AChR autoantibody titers, prevented ultrastructural damage of the postsynaptic membrane, improved neuromuscular transmission, and decreased myasthenic symptoms. This study thus underscores the potential of the therapeutic use of proteasome inhibitors to target plasma cells in Ab-mediated autoimmune diseases.
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Affiliation(s)
- Alejandro M Gomez
- Neuroimmunology Group, Department of Neuroscience, School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
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Gomez AM, Van Den Broeck J, Vrolix K, Janssen SP, Lemmens MAM, Van Der Esch E, Duimel H, Frederik P, Molenaar PC, Martínez-Martínez P, De Baets MH, Losen M. Antibody effector mechanisms in myasthenia gravis-pathogenesis at the neuromuscular junction. Autoimmunity 2010; 43:353-70. [PMID: 20380584 DOI: 10.3109/08916930903555943] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Myasthenia gravis (MG) is an autoimmune disorder caused by autoantibodies that are either directed to the muscle nicotinic acetylcholine receptor (AChR) or to the muscle-specific tyrosine kinase (MuSK). These autoantibodies define two distinct subforms of the disease-AChR-MG and MuSK-MG. Both AChR and MuSK are expressed on the postsynaptic membrane of the neuromuscular junction (NMJ), which is a highly specialized region of the muscle dedicated to receive and process signals from the motor nerve. Autoantibody binding to proteins of the postsynaptic membrane leads to impaired neuromuscular transmission and muscle weakness. Pro-inflammatory antibodies of the human IgG1 and IgG3 subclass modulate the AChR, cause complement activation, and attract lymphocytes; together acting to decrease levels of the AChR and AChR-associated proteins and to reduce postsynaptic folding. In patients with anti-MuSK antibodies, there is no evidence of loss of junctional folds and no apparent loss of AChR density. Anti-MuSK antibodies are predominantly of the IgG4 isotype, which functionally differs from other IgG subclasses in its anti-inflammatory activity. Moreover, IgG4 undergoes a posttranslational modification termed Fab arm exchange that prevents cross-linking of antigens. These findings suggest that MuSK-MG may be different in etiological and pathological mechanisms from AChR-MG. The effector functions of IgG subclasses on synapse structure and function are discussed in this review.
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Affiliation(s)
- Alejandro M Gomez
- Neuroimmunology Group, Department of Neuroscience, School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
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Wisse E, Braet F, Duimel H, Vreuls C, Koek G, Olde Damink SWM, van den Broek MAJ, De Geest B, Dejong CHC, Tateno C, Frederik P. Fixation methods for electron microscopy of human and other liver. World J Gastroenterol 2010; 16:2851-66. [PMID: 20556830 PMCID: PMC2887580 DOI: 10.3748/wjg.v16.i23.2851] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
For an electron microscopic study of the liver, expertise and complicated, time-consuming processing of hepatic tissues and cells is needed. The interpretation of electron microscopy (EM) images requires knowledge of the liver fine structure and experience with the numerous artifacts in fixation, embedding, sectioning, contrast staining and microscopic imaging. Hence, the aim of this paper is to present a detailed summary of different methods for the preparation of hepatic cells and tissue, for the purpose of preserving long-standing expertise and to encourage new investigators and clinicians to include EM studies of liver cells and tissue in their projects.
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van Tilborg GAF, Geelen T, Duimel H, Bomans PHH, Frederik PM, Sanders HMHF, Deckers NM, Deckers R, Reutelingsperger CPM, Strijkers GJ, Nicolay K. Internalization of annexin A5-functionalized iron oxide particles by apoptotic Jurkat cells. Contrast Media Mol Imaging 2009; 4:24-32. [PMID: 19137542 DOI: 10.1002/cmmi.261] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Apoptosis plays an important role in the etiology of various diseases. Several studies have reported on the use of annexin A5-functionalized iron oxide particles for the detection of apoptosis with MRI, both in vitro and in vivo. The protein annexin A5 binds with high affinity to the phospholipid phosphatidylserine, which is exposed in the outer leaflet of the apoptotic cell membrane. When co-exposed to apoptotic stimuli, this protein was shown to internalize into endocytic vesicles. Therefore in the present study we investigated the possible internalization of commercially available annexin A5-functionalized iron oxide particles (r1 = 34.0 +/- 2.1 and r2 = 205.0 +/- 10.4 mm(-1) s(-1) at 20 MHz), and the effects of their spatial distribution on relaxation rates R2*, R2 and R1. Two different incubation procedures were performed, where (1) Jurkat cells were either incubated with the contrast agent after induction of apoptosis or (2) Jurkat cells were simultaneously incubated with the apoptotic stimulus and the contrast agent. Transmission electron microscopy images and relaxation rates showed that the first incubation strategy mainly resulted in binding of the annexin A5-iron oxide particles to the cell membrane, whereas the second procedure allowed extensive membrane-association as well as a small amount of internalization. Owing to the small extent of internalization, only minor differences were observed between the DeltaR2*/DeltaR2 and DeltaR2/DeltaR1 ratios of cell pellets with membrane-associated or internalized annexin A5 particles. Only the increase in R1 (DeltaR1) appeared to be diminished by the internalization. Internalization of annexin A5-iron oxide particles is also expected to occur in vivo, where the apoptotic stimulus and the contrast agent are simultaneously present. Where the extent of internalization in vivo is similar to that observed in the present study, both T2- and T2*-weighted MR sequences are considered suitable for the detection of these particles in vivo.
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Affiliation(s)
- Geralda A F van Tilborg
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, The Netherlands.
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Martínez-Martínez P, Phernambucq M, Steinbusch L, Schaeffer L, Berrih-Aknin S, Duimel H, Frederik P, Molenaar P, De Baets MH, Losen M. Silencing rapsyn in vivo decreases acetylcholine receptors and augments sodium channels and secondary postsynaptic membrane folding. Neurobiol Dis 2009; 35:14-23. [PMID: 19344765 DOI: 10.1016/j.nbd.2009.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2008] [Revised: 02/23/2009] [Accepted: 03/18/2009] [Indexed: 10/21/2022] Open
Abstract
The receptor-associated protein of the synapse (rapsyn) is required for anchoring and stabilizing the nicotinic acetylcholine receptor (AChR) in the postsynaptic membrane of the neuromuscular junction (NMJ) during development. Here we studied the role of rapsyn in the maintenance of the adult NMJ by reducing rapsyn expression levels with short hairpin RNA (shRNA). Silencing rapsyn led to the average reduction of the protein levels of rapsyn (31% loss) and AChR (36% loss) at the NMJ within 2 weeks, corresponding to previously reported half life of these proteins. On the other hand, the sodium channel protein expression was augmented (66%) in rapsyn-silenced muscles. Unexpectedly, at the ultrastructural level a significant increase in the amount of secondary folds of the postsynaptic membrane in silenced muscles was observed. The neuromuscular transmission in rapsyn-silenced muscles was mildly impaired. The results suggest that the adult NMJ can rapidly produce postsynaptic folds to compensate for AChR and rapsyn loss.
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Affiliation(s)
- Pilar Martínez-Martínez
- Department of Neuroscience, School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands, Maastricht, The Netherlands.
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Wouters K, van Gorp PJ, Bieghs V, Gijbels MJ, Duimel H, Lütjohann D, Kerksiek A, van Kruchten R, Maeda N, Staels B, van Bilsen M, Shiri-Sverdlov R, Hofker MH. Dietary cholesterol, rather than liver steatosis, leads to hepatic inflammation in hyperlipidemic mouse models of nonalcoholic steatohepatitis. Hepatology 2008; 48:474-86. [PMID: 18666236 DOI: 10.1002/hep.22363] [Citation(s) in RCA: 367] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED Nonalcoholic steatohepatitis (NASH) involves liver lipid accumulation (steatosis) combined with hepatic inflammation. The transition towards hepatic inflammation represents a key step in pathogenesis, because it will set the stage for further liver damage, culminating in hepatic fibrosis, cirrhosis, and liver cancer. The actual risk factors that drive hepatic inflammation during the progression to NASH remain largely unknown. The role of steatosis and dietary cholesterol in the etiology of diet-induced NASH was investigated using hyperlipidemic mouse models fed a Western diet. Livers of male and female hyperlipidemic (low-density lipoprotein receptor-deficient [ldlr(-/-)] and apolipoprotein E2 knock-in [APOE2ki]) mouse models were compared with livers of normolipidemic wild-type (WT) C57BL/6J mice after short-term feeding with a high-fat diet with cholesterol (HFC) and without cholesterol. Whereas WT mice displayed only steatosis after a short-term HFC diet, female ldlr(-/-) and APOE2ki mice showed steatosis with severe inflammation characterized by infiltration of macrophages and increased nuclear factor kappaB (NF-kappaB) signaling. Remarkably, male ldlr(-/-) and APOE2ki mice developed severe hepatic inflammation in the absence of steatosis after 7 days on an HFC diet compared with WT animals. An HFC diet induced bloated, "foamy" Kupffer cells in male and female ldlr(-/-) and APOE2ki mice. Hepatic inflammation was found to be linked to increased plasma very low-density lipoprotein (VLDL) cholesterol levels. Omitting cholesterol from the HFC diet lowered plasma VLDL cholesterol and prevented the development of inflammation and hepatic foam cells. CONCLUSION These findings indicate that dietary cholesterol, possibly in the form of modified plasma lipoproteins, is an important risk factor for the progression to hepatic inflammation in diet-induced NASH.
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Affiliation(s)
- Kristiaan Wouters
- Department of Molecular Genetics, Physiology and Electron Microscopy Unit, Nutrition and Toxicology Research and Cardiovascular Research, Institutes of Maastricht University, Maastricht, The Netherlands
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Abstract
Skeletal muscle dysfunction is a well-recognised hallmark of chronic obstructive pulmonary disease (COPD) leading to exercise intolerance. The vastus lateralis of COPD patients is characterised by reduced mitochondrial enzyme activity; however, this is not the case in the tibialis anterior. It is, however, unclear whether the compromised oxidative capacity in the vastus is due to reduced mitochondrial volume density. Muscle biopsies were obtained from the vastus lateralis of six COPD patients and four healthy age-matched controls, and from the tibialis anterior of another six COPD patients and six controls. Mitochondrial number, fractional area and morphometry, as well as Z-line width (as a surrogate marker of fibre type), were analysed using transmission electron microscopy. Mitochondrial number (0.34 versus 0.63 n.microm(-2)) and fractional area (1.95 versus 4.25%) were reduced in the vastus of COPD patients compared with controls. Despite a reduced mitochondrial number (0.65 versus 0.88 n.microm(-2)), the mitochondrial fractional area was maintained in the tibialis of COPD patients compared with controls. It can be concluded that the reduced mitochondrial fractional area is likely to contribute to the decreased oxidative capacity in the vastus of chronic obstructive pulmonary disease patients, whereas the maintained mitochondrial fractional area in the tibialis may explain the normal oxidative capacity.
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Affiliation(s)
- H R Gosker
- Dept of Respiratory Medicine, Maastricht University, Nutrition and Toxicology Research Institute Maastricht, PO Box 616, 6200 MD Maastricht, The Netherlands.
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Martínez-Martínez P, Losen M, Duimel H, Frederik P, Spaans F, Molenaar P, Vincent A, De Baets MH. Overexpression of rapsyn in rat muscle increases acetylcholine receptor levels in chronic experimental autoimmune myasthenia gravis. Am J Pathol 2007; 170:644-57. [PMID: 17255332 PMCID: PMC1851878 DOI: 10.2353/ajpath.2007.060676] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The primary autoantigen in myasthenia gravis, the acetylcholine receptor (AChR), is clustered and anchored in the postsynaptic membrane of the neuromuscular junction by rapsyn. Previously, we found that overexpression of rapsyn by cDNA transfection protects AChRs in rat muscles from antibody-mediated loss in passive transfer experimental autoimmune myasthenia gravis (EAMG). Here, we determined whether rapsyn overexpression can reduce or even reverse AChR loss in muscles that are already damaged by chronic EAMG, which mimics the human disease. Active immunization against purified AChR was performed in female Lewis rats. Rapsyn overexpression resulted in an increase in total muscle membrane AChR levels, with some AChR at neuromuscular junctions but much of it in extrasynaptic membrane regions. At the ultrastructural level, most endplates in rapsyn-treated chronic EAMG muscles showed increased damage to the postsynaptic membrane. Although rapsyn overexpression stabilized AChRs in intact or mildly damaged endplates, the rapsyn-induced increase of membrane AChR enhanced autoantibody binding and membrane damage in severe ongoing disease. Thus, these results show the complexity of synaptic stabilization of AChR during the autoantibody attack. They also indicate that the expression of receptor-associated proteins may determine the severity of autoimmune diseases caused by anti-receptor antibodies.
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MESH Headings
- Animals
- Autoantibodies/immunology
- Autoantibodies/metabolism
- Chronic Disease
- Female
- Gene Expression
- Humans
- Motor Endplate/genetics
- Motor Endplate/immunology
- Motor Endplate/metabolism
- Motor Endplate/ultrastructure
- Muscle Proteins/biosynthesis
- Muscle Proteins/genetics
- Muscle Proteins/immunology
- Myasthenia Gravis, Autoimmune, Experimental/genetics
- Myasthenia Gravis, Autoimmune, Experimental/immunology
- Myasthenia Gravis, Autoimmune, Experimental/metabolism
- Myasthenia Gravis, Autoimmune, Experimental/pathology
- Rats
- Rats, Inbred Lew
- Receptors, Cholinergic/immunology
- Receptors, Cholinergic/metabolism
- Synaptic Membranes/immunology
- Synaptic Membranes/metabolism
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Affiliation(s)
- Pilar Martínez-Martínez
- Department of Neurology, Research Institute Brain and Behaviour, University of Maastricht, Maastricht University Hospital, The Netherlands.
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Snoeys J, Lievens J, Wisse E, Jacobs F, Duimel H, Collen D, Frederik P, De Geest B. Species differences in transgene DNA uptake in hepatocytes after adenoviral transfer correlate with the size of endothelial fenestrae. Gene Ther 2007; 14:604-12. [PMID: 17235290 DOI: 10.1038/sj.gt.3302899] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sinusoidal fenestrae may restrict the transport of gene transfer vectors according to their size. Using Vitrobot technology and cryo-electron microscopy, we show that the diameter of human adenoviral serotype 5 vectors is 93 nm with protruding fibers of 30 nm. Thus, a diameter of fenestrae of 150 nm or more is likely to be sufficient for passage of vectors from the sinusoidal lumen to the space of Disse and subsequent uptake of vectors in hepatocytes. The average diameter of fenestrae in New Zealand White rabbits (103+/-1.3 nm) was 1.4-fold (P<0.0001) lower than in C57BL/6 mice (141+/-5.4 nm). The percentage of sinusoidal fenestrae with a diameter larger than 150 nm was 10-fold (P<0.01) lower in rabbits (3.2+/-0.24%) than in C57BL/6 mice (32+/-5%), and this resulted in 8.8-fold (P=0.01) lower transgene DNA levels in hepatocytes in rabbits after adenoviral transfer. Injection of N-acetylcysteine combined with transient liver ischemia preceding intraportal transfer in rabbits increased the percentage of sinusoidal fenestrae above 150 nm 2.0-fold (P<0.001) and increased transgene DNA levels in hepatocytes 6.6-fold (P<0.05). In conclusion, species differences in transgene DNA uptake in hepatocytes after adenoviral transfer correlate with the diameter of fenestrae.
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Affiliation(s)
- J Snoeys
- Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
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Losen M, Stassen MHW, Martínez-Martínez P, Machiels BM, Duimel H, Frederik P, Veldman H, Wokke JHJ, Spaans F, Vincent A, De Baets MH. Increased expression of rapsyn in muscles prevents acetylcholine receptor loss in experimental autoimmune myasthenia gravis. ACTA ACUST UNITED AC 2005; 128:2327-37. [PMID: 16150851 DOI: 10.1093/brain/awh612] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Myasthenia gravis is usually caused by autoantibodies to the acetylcholine receptor (AChR). The AChR is clustered and anchored in the postsynaptic membrane of the neuromuscular junction (NMJ) by a cytoplasmic protein called rapsyn. We previously showed that resistance to experimental autoimmune myasthenia gravis (EAMG) in aged rats correlates with increased rapsyn concentration at the NMJ. It is possible, therefore, that endogenous rapsyn expression may be an important determinant of AChR loss and neuromuscular transmission failure in the human disease, and that upregulation of rapsyn expression could be used therapeutically. To examine first a potential therapeutic application of rapsyn upregulation, we induced acute EAMG in young rats by passive transfer of AChR antibody, mAb 35, and used in vivo electroporation to over-express rapsyn unilaterally in one tibialis anterior. We looked at the compound muscle action potentials (CMAPs) in the tibialis anterior, at rapsyn and AChR expression by quantitative radioimmunoassay and immunofluorescence, and at the morphology of the NMJs, comparing the electroporated and untreated muscles, as well as the control and EAMG rats. In control rats, transfected muscle fibres had extrasynaptic rapsyn aggregates, as well as slightly increased rapsyn and AChR concentrations at the NMJ. In EAMG rats, despite deposits of the membrane attack complex, the rapsyn-overexpressing muscles showed no decrement in the CMAPs, no loss of AChR, and the majority had normal postsynaptic folds, whereas endplates of untreated muscles showed typical AChR loss and morphological damage. These data suggest not only that increasing rapsyn expression could be a potential treatment for selected muscles of myasthenia gravis patients, but also lend support to the hypothesis that individual differences in innate rapsyn expression could be a factor in determining disease severity.
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MESH Headings
- Action Potentials/physiology
- Acute Disease
- Animals
- Electromyography/methods
- Female
- Fluorescent Antibody Technique/methods
- Immunohistochemistry/methods
- Microscopy, Confocal/methods
- Microscopy, Electron/methods
- Muscle Proteins/analysis
- Muscle Proteins/genetics
- Muscle, Skeletal/pathology
- Muscle, Skeletal/physiopathology
- Myasthenia Gravis, Autoimmune, Experimental/genetics
- Myasthenia Gravis, Autoimmune, Experimental/pathology
- Myasthenia Gravis, Autoimmune, Experimental/physiopathology
- Neuromuscular Junction/genetics
- Neuromuscular Junction/pathology
- Neuromuscular Junction/physiopathology
- Radioimmunoassay/methods
- Rats
- Rats, Inbred Lew
- Receptors, Cholinergic/genetics
- Synaptic Transmission/genetics
- Synaptic Transmission/physiology
- Up-Regulation/genetics
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Affiliation(s)
- Mario Losen
- Department of Neurology, Research Institute Brain and Behaviour, University of Maastricht, The Netherlands
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Ausma J, Litjens N, Lenders MH, Duimel H, Mast F, Wouters L, Ramaekers F, Allessie M, Borgers M. Time course of atrial fibrillation-induced cellular structural remodeling in atria of the goat. J Mol Cell Cardiol 2001; 33:2083-94. [PMID: 11735256 DOI: 10.1006/jmcc.2001.1472] [Citation(s) in RCA: 157] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Previously we documented cellular structural changes of a non-degenerative nature in atrial myocytes after atrial fibrillation (AF) in the goat. The time course of these changes was not studied. METHODS AND RESULTS Cellular structural changes were studied by light- and electron microscopy and immunohistochemistry in goat atria after 0-16 weeks AF. The first sign of cellular structural remodeling was a more homogeneous chromatin distribution, at 1 week of AF. Sub-structural changes in mitochondria and sarcoplasmic reticulum occurred gradually. Cellular degeneration was absent. The degree of myolysis and glycogen accumulation increased till 8 weeks of AF and did not increase further from thereon. After 16 weeks of AF, 42% of the myocytes in the right atrial free wall were affected by myolysis. The diameter of the atrial myocytes increased. Dedifferentiation of the atrial myocytes was suggested by altered expression patterns of structural proteins, such as the disappearance of cardiotin (1 week), the A-I junctional part of titin (4 weeks), desmin at the intercalated disk (ID) (8 weeks) and a gradual re-expression of alpha-smooth muscle actin. CONCLUSION Remodeling of the cellular ultrastructure in atrial myocardium of the goat develops progressively during AF. Re-expression of fetal proteins indicate dedifferentiation of atrial myocytes, analogous to observations in hibernating myocardium of the ventricle.
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Affiliation(s)
- J Ausma
- Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands.
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31
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Ausma J, Coumans WA, Duimel H, Van der Vusse GJ, Allessie MA, Borgers M. Atrial high energy phosphate content and mitochondrial enzyme activity during chronic atrial fibrillation. Cardiovasc Res 2000; 47:788-96. [PMID: 10974227 DOI: 10.1016/s0008-6363(00)00139-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE Prolonged atrial fibrillation (AF) results in (ultra)structural remodelling of atrial cardiomyocytes resembling alterations seen in ischemia-induced ventricular hibernation. The mechanisms underlying these changes are incompletely understood. In the present study we explored the hypothesis that a profound imbalance in energy status during chronic AF acts as a stimulus for structural remodelling. METHODS AND RESULTS The content of high energy-phosphates and related compounds together with a selected number of mitochondrial enzymes, known to be altered under ischemic conditions, were determined in tissue samples taken from atria of goats in sinus rhythm (SR) and after 1, 2, 4, 8 and 16 weeks of AF maintained by burst pacing. Atrial remodelling was quantified by counting the percentage of cells with >10% myolysis. During AF structural remodelling developed progressively, after 8 weeks about 40% of the atrial myocytes were affected. The concentration of adenine nucleotides and their degradation products did not change significantly during AF. Also the activity of mitochondrial cytochrome c oxidase activity was similar during AF and SR. Mitochondrial NADH-oxidase and proton-translocating ATPase activities were not induced by AF. The tissue content of phosphocreatine decreased during the first week by 60%, but completely recovered between 8 and 16 weeks of AF. CONCLUSIONS The analysis of adenine nucleotides during AF provided no indication for the development of severe atrial ischemia. This notion is supported by enzyme cytochemical findings. However, AF-induced atrial remodelling was associated with a transient lowering of phosphocreatine content, suggesting an increase in energy demand during the early phase of AF. The subsequent recovery of the phosphocreatine pool indicates restoration of the balance between energy demand and supply in chronically fibrillating atria.
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Affiliation(s)
- J Ausma
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands.
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32
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Ausma J, Dispersyn GD, Duimel H, Thoné F, Ver Donck L, Allessie MA, Borgers M. Changes in ultrastructural calcium distribution in goat atria during atrial fibrillation. J Mol Cell Cardiol 2000; 32:355-64. [PMID: 10731435 DOI: 10.1006/jmcc.1999.1090] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
It has been suggested that Ca(2+)content of atrial cardiomyocytes is increased at the onset of atrial fibrillation (AF). Whether this phenomenon is transient is currently unknown. Therefore, in this study the time-related changes in Ca(2+)location in atrial myocytes from goats with chronic AF have been investigated. The distribution of calcium was assessed with the electron microscope using the cytochemical phosphate-pyroantimonate and oxalate-pyroantimonate methods in atrial biopsies from goats in sinus rhythm and goats with 1-16 weeks of burst-pacing-induced AF. In atrial myocytes from control goats in sinus rhythm, a normal Ca(2+)distribution was observed, with regular deposits along the sarcolemma (an average of 3.4 deposits per microm at a regular distance). The number of sarcolemma-bound Ca(2+)deposits substantially increased after 1 and 2 weeks of atrial fibrillation. After this period the amount of Ca(2+)precipitate decreased at 4 and 8 weeks, and became below control level at 16 weeks. A similar time-related redistribution of Ca(2+)occurred in mitochondria. Whereas mitochondria from control goats displayed very few Ca(2+)deposits (average 4.0 deposits per micro m(2)), their number markedly increased after 1 and 2 weeks of atrial fibrillation, which indicates cellular Ca(2+)overload. From 4 weeks, Ca(2+)deposits reached control levels and were below control level after 16 weeks of atrial fibrillation (2.5 deposits per microm(2)). Our findings are consistent with the previously observed Ca(2+)overload early after the onset of atrial fibrillation. The present study shows that this overload persists for at least 2 weeks, after which the cardiomyocytes apparently adapt to a new Ca(2+)homeostasis, thereby avoiding Ca(2+)overload. This protection against Ca(2+)overload co-occurs with dedifferentiation like cellular remodeling.
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Affiliation(s)
- J Ausma
- Department of Physiology, Maastricht University, The Netherlands.
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