1
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Ghézali G, Ribot J, Curry N, Pillet LE, Boutet-Porretta F, Mozheiko D, Calvo CF, Ezan P, Perfettini I, Lecoin L, Janel S, Zapata J, Escartin C, Etienne-Manneville S, Kaminski CF, Rouach N. Connexin 30 locally controls actin cytoskeleton and mechanical remodeling in motile astrocytes. Glia 2024; 72:1915-1929. [PMID: 38982826 DOI: 10.1002/glia.24590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 06/04/2024] [Accepted: 06/25/2024] [Indexed: 07/11/2024]
Abstract
During brain maturation, astrocytes establish complex morphologies unveiling intense structural plasticity. Connexin 30 (Cx30), a gap-junction channel-forming protein expressed postnatally, dynamically regulates during development astrocyte morphological properties by controlling ramification and extension of fine processes. However, the underlying mechanisms remain unexplored. Here, we found in vitro that Cx30 interacts with the actin cytoskeleton in astrocytes and inhibits its structural reorganization and dynamics during cell migration. This translates into an alteration of local physical surface properties, as assessed by correlative imaging using stimulated emission depletion (STED) super resolution imaging and atomic force microscopy (AFM). Specifically, Cx30 impaired astrocyte cell surface topology and cortical stiffness in motile astrocytes. As Cx30 alters actin organization, dynamics, and membrane physical properties, we assessed whether it controls astrocyte migration. We found that Cx30 reduced persistence and directionality of migrating astrocytes. Altogether, these data reveal Cx30 as a brake for astrocyte structural and mechanical plasticity.
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Affiliation(s)
- Grégory Ghézali
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
- Doctoral School N° 158, Sorbonne Université, Paris, France
| | - Jérôme Ribot
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
| | - Nathan Curry
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Laure-Elise Pillet
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
- Doctoral School N°562, Université Paris Cité, Paris, France
| | - Flora Boutet-Porretta
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
- Doctoral School N° 158, Sorbonne Université, Paris, France
| | - Daria Mozheiko
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
- Doctoral School N° 158, Sorbonne Université, Paris, France
| | - Charles-Félix Calvo
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
| | - Pascal Ezan
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
| | - Isabelle Perfettini
- Institut Pasteur, Université de Paris, CNRS, Cell Polarity, Migration and Cancer Unit, Paris, France
| | - Laure Lecoin
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
| | - Sébastien Janel
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Jonathan Zapata
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
| | - Carole Escartin
- Université Paris-Saclay, CEA, CNRS, MIRCen, Laboratoire des Maladies Neurodégénératives, Fontenay-aux-Roses, France
| | | | - Clemens F Kaminski
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Nathalie Rouach
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
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2
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Pillai EK, Franze K. Mechanics in the nervous system: From development to disease. Neuron 2024; 112:342-361. [PMID: 37967561 DOI: 10.1016/j.neuron.2023.10.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/29/2023] [Accepted: 10/04/2023] [Indexed: 11/17/2023]
Abstract
Physical forces are ubiquitous in biological processes across scales and diverse contexts. This review highlights the significance of mechanical forces in nervous system development, homeostasis, and disease. We provide an overview of mechanical signals present in the nervous system and delve into mechanotransduction mechanisms translating these mechanical cues into biochemical signals. During development, mechanical cues regulate a plethora of processes, including cell proliferation, differentiation, migration, network formation, and cortex folding. Forces then continue exerting their influence on physiological processes, such as neuronal activity, glial cell function, and the interplay between these different cell types. Notably, changes in tissue mechanics manifest in neurodegenerative diseases and brain tumors, potentially offering new diagnostic and therapeutic target opportunities. Understanding the role of cellular forces and tissue mechanics in nervous system physiology and pathology adds a new facet to neurobiology, shedding new light on many processes that remain incompletely understood.
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Affiliation(s)
- Eva K Pillai
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK; Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, 69117 Heidelberg, Germany; Developmental Biology Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, 69117 Heidelberg, Germany.
| | - Kristian Franze
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK; Institute of Medical Physics and Microtissue Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestraße 91, 91052 Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, Kussmaulallee 1, 91054 Erlangen, Germany.
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3
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Rybachuk O, Nesterenko Y, Pinet É, Medvediev V, Yaminsky Y, Tsymbaliuk V. Neuronal differentiation and inhibition of glial differentiation of murine neural stem cells by pHPMA hydrogel for the repair of injured spinal cord. Exp Neurol 2023; 368:114497. [PMID: 37517459 DOI: 10.1016/j.expneurol.2023.114497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 06/22/2023] [Accepted: 07/23/2023] [Indexed: 08/01/2023]
Abstract
Currently, several therapeutic methods of treating the effects of spinal cord injury (SCI) are being considered. On the one hand, transplantation of stem cells (SCs), in particular, neural stem/progenitor cells (NSPCs), is promising, as these cells have the potential to differentiate into nervous tissue cells, able to enhance endogenous regeneration and prevent the development of inflammatory processes. On the other hand, it is quite promising to replace the damaged nervous tissue with synthetic matrices, in particular hydrogels, which can create artificial conditions for the regenerative growth of injured nerve fibers through the spinal cord injury area, i.e. stimulate and support axonal regeneration and myelination. In this work, we combined both of these novel approaches by populating (injecting or rehydrating) a heteroporous pHPMA hydrogel (NeuroGel) with murine hippocampal NSPCs. Being inside the hydrogel (10 days of cultivation), NSPCs were more differentiated into neurons: 19.48% ± 1.71% (the NSPCs injection into the hydrogel) and 36.49% ± 4.20% (the hydrogel rehydration in the NSPCs suspension); in control cultures, the level of differentiation in neurons was only 2.40% ± 0.31%. Differentiation of NSPCs into glial cells, in particular into oligodendrocyte progenitor cells, was also observed - 8.89% ± 2.15% and 6.21% ± 0.80% for injection and rehydration variants, respectively; in control - 28.75% ± 2.08%. In the control NSPCs culture, there was a small number of astrocytes - 2.11% ± 0.43%. Inside the hydrogel, NSPCs differentiation in astrocytes was not observed. In vitro data showed that the hydrogel promotes the differentiation of NSPCs into neurons, and inhibits the differentiation into glial cells. And in vivo showed post-traumatic recovery of rat spinal cord tissue after injury followed by implantation of the hydrogel+NSPCs complex (approximately 7 months after SCI). The implant area was closely connected with the recipient tissue, and the recipient cells freely grew into the implant itself. Inside the implant, a formed dense neuronal network was visible. In summary, the results are primarily an experimental ground for further studies of implants based on pHPMA hydrogel with populated different origin SCs, and the data also indicate the feasibility and efficiency of using an integrated approach to reduce possible negative side effects and facilitate the rehabilitation process after a SCI.
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Affiliation(s)
- Oksana Rybachuk
- Bogomoletz Institute of Physiology NAS of Ukraine, Kyiv 01601, Ukraine; State Institution National Scientific Center the M.D. Strazhesko Institute of Cardiology, Clinical and Regenerative Medicine, NAMS of Ukraine, Kyiv 03680, Ukraine.
| | - Yuliia Nesterenko
- Bogomoletz Institute of Physiology NAS of Ukraine, Kyiv 01601, Ukraine
| | | | - Volodymyr Medvediev
- Bogomoletz Institute of Physiology NAS of Ukraine, Kyiv 01601, Ukraine; Bogomolets National Medical University, Kyiv 01601, Ukraine
| | - Yurii Yaminsky
- State Institution "Romodanov Neurosurgery Institute, National Academy of Medical Sciences of Ukraine", Kyiv 04050, Ukraine
| | - Vitaliy Tsymbaliuk
- Bogomolets National Medical University, Kyiv 01601, Ukraine; State Institution "Romodanov Neurosurgery Institute, National Academy of Medical Sciences of Ukraine", Kyiv 04050, Ukraine
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Abstract
Recently, substrate stiffness has been involved in the physiology and pathology of the nervous system. However, the role and function of substrate stiffness remain unclear. Here, we review known effects of substrate stiffness on nerve cell morphology and function in the central and peripheral nervous systems and their involvement in pathology. We hope this review will clarify the research status of substrate stiffness in nerve cells and neurological disorder.
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Affiliation(s)
- Weijin Si
- Key Laboratory of Cognitive Science, Hubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis & Treatment, Laboratory of Membrane Ion Channels and Medicine, College of Biomedical Engineering, South-Central Minzu University, Wuhan 430074, China
| | - Jihong Gong
- Key Laboratory of Cognitive Science, Hubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis & Treatment, Laboratory of Membrane Ion Channels and Medicine, College of Biomedical Engineering, South-Central Minzu University, Wuhan 430074, China
| | - Xiaofei Yang
- Key Laboratory of Cognitive Science, Hubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis & Treatment, Laboratory of Membrane Ion Channels and Medicine, College of Biomedical Engineering, South-Central Minzu University, Wuhan 430074, China
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5
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Excitatory/inhibitory imbalance in autism: the role of glutamate and GABA gene-sets in symptoms and cortical brain structure. Transl Psychiatry 2023; 13:18. [PMID: 36681677 PMCID: PMC9867712 DOI: 10.1038/s41398-023-02317-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 12/22/2022] [Accepted: 01/10/2023] [Indexed: 01/22/2023] Open
Abstract
The excitatory/inhibitory (E/I) imbalance hypothesis posits that imbalance between excitatory (glutamatergic) and inhibitory (GABAergic) mechanisms underlies the behavioral characteristics of autism. However, how E/I imbalance arises and how it may differ across autism symptomatology and brain regions is not well understood. We used innovative analysis methods-combining competitive gene-set analysis and gene-expression profiles in relation to cortical thickness (CT) to investigate relationships between genetic variance, brain structure and autism symptomatology of participants from the AIMS-2-TRIALS LEAP cohort (autism = 359, male/female = 258/101; neurotypical control participants = 279, male/female = 178/101) aged 6-30 years. Using competitive gene-set analyses, we investigated whether aggregated genetic variation in glutamate and GABA gene-sets could be associated with behavioral measures of autism symptoms and brain structural variation. Further, using the same gene-sets, we corelated expression profiles throughout the cortex with differences in CT between autistic and neurotypical control participants, as well as in separate sensory subgroups. The glutamate gene-set was associated with all autism symptom severity scores on the Autism Diagnostic Observation Schedule-2 (ADOS-2) and the Autism Diagnostic Interview-Revised (ADI-R) within the autistic group. In adolescents and adults, brain regions with greater gene-expression of glutamate and GABA genes showed greater differences in CT between autistic and neurotypical control participants although in opposing directions. Additionally, the gene expression profiles were associated with CT profiles in separate sensory subgroups. Our results suggest complex relationships between E/I related genetics and autism symptom profiles as well as brain structure alterations, where there may be differential roles for glutamate and GABA.
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6
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Kumarapuram S, Kunnath AJ, Omelchenko A, Boustany NN, Firestein BL. Glutamate Receptors Mediate Changes to Dendritic Mitochondria in Neurons Grown on Stiff Substrates. Ann Biomed Eng 2022; 50:1116-1133. [PMID: 35652995 DOI: 10.1007/s10439-022-02987-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 05/23/2022] [Indexed: 11/25/2022]
Abstract
The stiffness of brain tissue changes during development and disease. These changes can affect neuronal morphology, specifically dendritic arborization. We previously reported that N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors regulate dendrite number and branching in a manner that is dependent on substrate stiffness. Since mitochondria affect the shape of dendrites, in this study, we determined whether the stiffness of substrates on which rat hippocampal neurons are grown affects mitochondrial characteristics and if glutamate receptors mediate the effects of substrate stiffness. Dendritic mitochondria are small, short, simple, and scarce in neurons cultured on substrates of 0.5 kPa stiffness. In contrast, dendritic mitochondria are large, long, complex, and low in number in neurons grown on substrates of 4 kPa stiffness. Dendritic mitochondria of neurons cultured on glass are high in number and small with complex shapes. Treatment of neurons grown on the stiffer gels or glass with the NMDA and AMPA receptor antagonists, 2-amino-5-phosphonopentanoic acid and 6-cyano-7-nitroquinoxaline-2,3-dione, respectively, results in mitochondrial characteristics of neurons grown on the softer substrate. These results suggest that glutamate receptors play important roles in regulating both mitochondrial morphology and dendritic arborization in response to substrate stiffness.
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Affiliation(s)
- Siddhant Kumarapuram
- Department of Cell Biology and Neuroscience, Rutgers University, 604 Allison Road, Piscataway, NJ, 08854-8082, USA
| | - Ansley J Kunnath
- Department of Cell Biology and Neuroscience, Rutgers University, 604 Allison Road, Piscataway, NJ, 08854-8082, USA
| | - Anton Omelchenko
- Department of Cell Biology and Neuroscience, Rutgers University, 604 Allison Road, Piscataway, NJ, 08854-8082, USA.,Neurosciences Graduate Program, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Nada N Boustany
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Bonnie L Firestein
- Department of Cell Biology and Neuroscience, Rutgers University, 604 Allison Road, Piscataway, NJ, 08854-8082, USA.
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Cameron T, Bennet T, Rowe EM, Anwer M, Wellington CL, Cheung KC. Review of Design Considerations for Brain-on-a-Chip Models. MICROMACHINES 2021; 12:441. [PMID: 33921018 PMCID: PMC8071412 DOI: 10.3390/mi12040441] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/12/2021] [Accepted: 04/12/2021] [Indexed: 02/06/2023]
Abstract
In recent years, the need for sophisticated human in vitro models for integrative biology has motivated the development of organ-on-a-chip platforms. Organ-on-a-chip devices are engineered to mimic the mechanical, biochemical and physiological properties of human organs; however, there are many important considerations when selecting or designing an appropriate device for investigating a specific scientific question. Building microfluidic Brain-on-a-Chip (BoC) models from the ground-up will allow for research questions to be answered more thoroughly in the brain research field, but the design of these devices requires several choices to be made throughout the design development phase. These considerations include the cell types, extracellular matrix (ECM) material(s), and perfusion/flow considerations. Choices made early in the design cycle will dictate the limitations of the device and influence the end-point results such as the permeability of the endothelial cell monolayer, and the expression of cell type-specific markers. To better understand why the engineering aspects of a microfluidic BoC need to be influenced by the desired biological environment, recent progress in microfluidic BoC technology is compared. This review focuses on perfusable blood-brain barrier (BBB) and neurovascular unit (NVU) models with discussions about the chip architecture, the ECM used, and how they relate to the in vivo human brain. With increased knowledge on how to make informed choices when selecting or designing BoC models, the scientific community will benefit from shorter development phases and platforms curated for their application.
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Affiliation(s)
- Tiffany Cameron
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (T.C.); (T.B.)
- Centre for Blood Research, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Tanya Bennet
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (T.C.); (T.B.)
- Centre for Blood Research, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Elyn M. Rowe
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (E.M.R.); (M.A.); (C.L.W.)
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Mehwish Anwer
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (E.M.R.); (M.A.); (C.L.W.)
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Cheryl L. Wellington
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (E.M.R.); (M.A.); (C.L.W.)
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Karen C. Cheung
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (T.C.); (T.B.)
- Centre for Blood Research, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Department of Electrical & Computer Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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8
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Crosta CM, Hernandez K, Bhattiprolu AK, Fu AY, Moore JC, Clarke SG, Dudzinski NR, Brzustowicz LM, Paradiso KG, Firestein BL. Characterization hiPSC-derived neural progenitor cells and neurons to investigate the role of NOS1AP isoforms in human neuron dendritogenesis. Mol Cell Neurosci 2020; 109:103562. [PMID: 32987141 PMCID: PMC7736313 DOI: 10.1016/j.mcn.2020.103562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 09/02/2020] [Accepted: 09/22/2020] [Indexed: 01/30/2023] Open
Abstract
Abnormal dendritic arbor development has been implicated in a number of neurodevelopmental disorders, such as autism and Rett syndrome, and the neuropsychiatric disorder schizophrenia. Postmortem brain samples from subjects with schizophrenia show elevated levels of NOS1AP in the dorsolateral prefrontal cortex, a region of the brain associated with cognitive function. We previously reported that the long isoform of NOS1AP (NOS1AP-L), but not the short isoform (NOS1AP-S), negatively regulates dendrite branching in rat hippocampal neurons. To investigate the role that NOS1AP isoforms play in human dendritic arbor development, we adapted methods to generate human neural progenitor cells and neurons using induced pluripotent stem cell (iPSC) technology. We found that increased protein levels of either NOS1AP-L or NOS1AP-S decrease dendrite branching in human neurons at the developmental time point when primary and secondary branching actively occurs. Next, we tested whether pharmacological agents can decrease the expression of NOS1AP isoforms. Treatment of human iPSC-derived neurons with d-serine, but not clozapine, haloperidol, fluphenazine, or GLYX-13, results in a reduction in endogenous NOS1AP-L, but not NOS1AP-S, protein expression; however, d-serine treatment does not reverse decreases in dendrite number mediated by overexpression of NOS1AP isoforms. In summary, we demonstrate how an in vitro model of human neuronal development can help in understanding the etiology of schizophrenia and can also be used as a platform to screen drugs for patients.
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Affiliation(s)
- Christen M Crosta
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA; Neurosciences Graduate Program, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Kristina Hernandez
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA; Molecular Biosciences Graduate Program, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Atul K Bhattiprolu
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Allen Y Fu
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Jennifer C Moore
- Department of Genetics, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854-8082, USA
| | - Stephen G Clarke
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Natasha R Dudzinski
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Linda M Brzustowicz
- Department of Genetics, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854-8082, USA
| | - Kenneth G Paradiso
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Bonnie L Firestein
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
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Liu H, Bian W, Yang D, Yang M, Luo H. Inhibiting the Piezo1 channel protects microglia from acute hyperglycaemia damage through the JNK1 and mTOR signalling pathways. Life Sci 2020; 264:118667. [PMID: 33127514 DOI: 10.1016/j.lfs.2020.118667] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 10/21/2020] [Accepted: 10/23/2020] [Indexed: 01/20/2023]
Abstract
AIM Diabetes is a high-risk factor for neurocognitive dysfunction. Diabetic acute hyperglycaemia accompanied by high osmotic pressure can induce immune cell dysfunction, but its mechanism of action in brain microglia remains unclear. This study aimed to evaluate the role of the mechanically sensitive ion channel Piezo1 in the dysfunction of microglia in acute hyperglycaemia. MATERIALS AND METHODS To construct an in vitro acute hyperglycaemia model using the BV2 microglial cell line, Piezo1 in microglia was inhibited by GsMTx4 and siRNA, and the changes in microglial function were further evaluated. KEY FINDINGS High concentrations of glucose upregulated the expression of Piezo1, led to weakened cell proliferation and migration, and reduced the immune response to inflammatory stimulating factors (Aβ and LPS). Additionally, LPS upregulated Piezo1 in BV2 microglial cultures in vitro. The activation of Piezo1 channels increased the intracellular Ca2+ concentration and reduced the phosphorylation of JNK1 and mTOR. Inhibiting Piezo1 did not affect cell viability at average glucose concentrations but improved acute HCG-induced cell damage and increased the phosphorylation of JNK1 and mTOR, suggesting that the latter modification may be a potential downstream mechanism of Piezo1. SIGNIFICANCE Piezo1 is necessary for microglial damage in acute hyperglycaemia and may become a promising target to treat hyperglycaemic brain injury.
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Affiliation(s)
- Hailin Liu
- Department of Anesthesiology, The Third Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330008, China; Jiangxi Key Laboratory of Cancer Metastasis and Precision Treatment, The Third Affiliated Hospital of Nanchang University, Nanchang, China; Graduate School of School of Medicine, Nanchang University, China
| | - Wengong Bian
- Department of Anesthesiology, The Third Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330008, China; Jiangxi Key Laboratory of Cancer Metastasis and Precision Treatment, The Third Affiliated Hospital of Nanchang University, Nanchang, China; Graduate School of School of Medicine, Nanchang University, China
| | - Dongxia Yang
- Department of Anesthesiology, The Third Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330008, China; Jiangxi Key Laboratory of Cancer Metastasis and Precision Treatment, The Third Affiliated Hospital of Nanchang University, Nanchang, China; Graduate School of School of Medicine, Nanchang University, China
| | - Mingmin Yang
- Department of Anesthesiology, The Third Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330008, China
| | - Heguo Luo
- Department of Anesthesiology, The Third Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330008, China.
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Ghane N, Beigi MH, Labbaf S, Nasr-Esfahani MH, Kiani A. Design of hydrogel-based scaffolds for the treatment of spinal cord injuries. J Mater Chem B 2020; 8:10712-10738. [DOI: 10.1039/d0tb01842b] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Hydrogel-based scaffold design approaches for the treatment of spinal cord injuries.
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Affiliation(s)
- Nazanin Ghane
- Department of Cellular Biotechnology Cell Science Research Center
- Royan Institute for Biotechnology
- ACECR
- Isfahan
- Iran
| | - Mohammad-Hossein Beigi
- Department of Cellular Biotechnology Cell Science Research Center
- Royan Institute for Biotechnology
- ACECR
- Isfahan
- Iran
| | - Sheyda Labbaf
- Biomaterials Research Group
- Department of Materials Engineering
- Isfahan University of Technology
- Isfahan
- Iran
| | | | - Amirkianoosh Kiani
- Silicon Hall: Micro/Nano Manufacturing Facility
- Faculty of Engineering and Applied Science
- Ontario Tech University
- Ontario
- Canada
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11
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Wagner K, Girardo S, Goswami R, Rosso G, Ulbricht E, Müller P, Soteriou D, Träber N, Guck J. Colloidal crystals of compliant microgel beads to study cell migration and mechanosensitivity in 3D. SOFT MATTER 2019; 15:9776-9787. [PMID: 31742293 DOI: 10.1039/c9sm01226e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Tissues are defined not only by their biochemical composition, but also by their distinct mechanical properties. It is now widely accepted that cells sense their mechanical environment and respond to it. However, studying the effects of mechanics in in vitro 3D environments is challenging since current 3D hydrogel assays convolve mechanics with gel porosity and adhesion. Here, we present novel colloidal crystals as modular 3D scaffolds where these parameters are principally decoupled by using monodisperse, protein-coated PAAm microgel beads as building blocks, so that variable stiffness regions can be achieved within one 3D colloidal crystal. Characterization of the colloidal crystal and oxygen diffusion simulations suggested the suitability of the scaffold to support cell survival and growth. This was confirmed by live-cell imaging and fibroblast culture over a period of four days. Moreover, we demonstrate unambiguous durotactic fibroblast migration and mechanosensitive neurite outgrowth of dorsal root ganglion neurons in 3D. This modular approach of assembling 3D scaffolds from mechanically and biochemically well-defined building blocks allows the spatial patterning of stiffness decoupled from porosity and adhesion sites in principle and provides a platform to investigate mechanosensitivity in 3D environments approximating tissues in vitro.
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Affiliation(s)
- Katrin Wagner
- Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
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12
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Yu Y, Liu S, Wu X, Yu Z, Xu Y, Zhao W, Zavodnik I, Zheng J, Li C, Zhao H. Mechanism of Stiff Substrates up-Regulate Cultured Neuronal Network Activity. ACS Biomater Sci Eng 2019; 5:3475-3482. [PMID: 33405731 DOI: 10.1021/acsbiomaterials.9b00225] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Our previous work provided compelling evidence showing that substrate stiffness is crucial for regulating synaptic connectivity and excitatory synaptic transmission among neurons in the neuronal network. However, the underlying mechanisms remain elusive. In our study, polydimethylsiloxane (PDMS) substrates with different stiffness have been fabricated to investigate the mechanisms by which the substrate stiffness upregulates the formation and activity of the cultured neuronal network. Here we report that stiff substrate increased both the number of synapses and the efficacy of excitatory synaptic transmission. More colocalization of synaptotagmin and PSD-95 was observed in the neuronal network on stiff substrate, which indicated the synapse number has increased. We also found that the increased synapse number was mediated by Hevin and SPARC that are secreted from astrocyte. The increased efficacy of excitatory synaptic transmission induced by stiff substrate was explored in three aspects. First, stiff substrate enhanced the presynaptic activity through increasing the vesicular release probability (Pr) of neurotransmitters as well as the calcium influx. Second, stiff substrate reduced voltage-dependent Mg2+ blockade to N-methyl-d-aspartate receptor (NMDAR) channels, which led to higher postsynaptic activity. Third, our work suggested that the increased excitatory synaptic transmission in the neural network on stiff substrate involved the upregulated synaptic glutamate concentration. Taken together, these findings may provide a molecular mechanism underlying substrate stiffness regulation of excitatory synaptic transmission in the cultured neural network.
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Affiliation(s)
- Yang Yu
- Institute of Biomechanics and Medical Engineering, School of Aerospace Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Sisi Liu
- Institute of Biomechanics and Medical Engineering, School of Aerospace Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Xiaoan Wu
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, Florida 33136, United States
| | - Zhang Yu
- Institute of Biomechanics and Medical Engineering, School of Aerospace Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Yishi Xu
- Beijing No. 4 High School, Beijing 100034, People's Republic of China
| | - Weijiang Zhao
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong 515041, People's Republic of China
| | - Ilya Zavodnik
- Department of Biochemistry, Yanka Kupala State University Grodno, Blvd Len Kom 50, Grodno 230030, Belarus
| | - Jinping Zheng
- Department of Physiology, Changzhi Medical College, Changzhi 046000, People's Republic of China
| | - Chen Li
- Department of Physiology, Changzhi Medical College, Changzhi 046000, People's Republic of China
| | - Hucheng Zhao
- Institute of Biomechanics and Medical Engineering, School of Aerospace Engineering, Tsinghua University, Beijing 100084, People's Republic of China
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Velasco-Estevez M, Mampay M, Boutin H, Chaney A, Warn P, Sharp A, Burgess E, Moeendarbary E, Dev KK, Sheridan GK. Infection Augments Expression of Mechanosensing Piezo1 Channels in Amyloid Plaque-Reactive Astrocytes. Front Aging Neurosci 2018; 10:332. [PMID: 30405400 PMCID: PMC6204357 DOI: 10.3389/fnagi.2018.00332] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 10/01/2018] [Indexed: 01/07/2023] Open
Abstract
A defining pathophysiological hallmark of Alzheimer's disease (AD) is the amyloid plaque; an extracellular deposit of aggregated fibrillar Aβ1-42 peptides. Amyloid plaques are hard, brittle structures scattered throughout the hippocampus and cerebral cortex and are thought to cause hyperphosphorylation of tau, neurofibrillary tangles, and progressive neurodegeneration. Reactive astrocytes and microglia envelop the exterior of amyloid plaques and infiltrate their inner core. Glia are highly mechanosensitive cells and can almost certainly sense the mismatch between the normally soft mechanical environment of the brain and very stiff amyloid plaques via mechanosensing ion channels. Piezo1, a non-selective cation channel, can translate extracellular mechanical forces to intracellular molecular signaling cascades through a process known as mechanotransduction. Here, we utilized an aging transgenic rat model of AD (TgF344-AD) to study expression of mechanosensing Piezo1 ion channels in amyloid plaque-reactive astrocytes. We found that Piezo1 is upregulated with age in the hippocampus and cortex of 18-month old wild-type rats. However, more striking increases in Piezo1 were measured in the hippocampus of TgF344-AD rats compared to age-matched wild-type controls. Interestingly, repeated urinary tract infections with Escherichia coli bacteria, a common comorbidity in elderly people with dementia, caused further elevations in Piezo1 channel expression in the hippocampus and cortex of TgF344-AD rats. Taken together, we report that aging and peripheral infection augment amyloid plaque-induced upregulation of mechanoresponsive ion channels, such as Piezo1, in astrocytes. Further research is required to investigate the role of astrocytic Piezo1 in the Alzheimer's brain, whether modulating channel opening will protect or exacerbate the disease state, and most importantly, if Piezo1 could prove to be a novel drug target for age-related dementia.
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Affiliation(s)
- María Velasco-Estevez
- Neuroimmulology & Neurotherapeutics Laboratory, School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, United Kingdom
- Drug Development, Department of Physiology, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Myrthe Mampay
- Neuroimmulology & Neurotherapeutics Laboratory, School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, United Kingdom
| | - Hervé Boutin
- Wolfson Molecular Imaging Centre, Faculty of Biology, Medicine and Health and Manchester Academic Health Sciences Centre, The University of Manchester, Manchester, United Kingdom
| | - Aisling Chaney
- Wolfson Molecular Imaging Centre, Faculty of Biology, Medicine and Health and Manchester Academic Health Sciences Centre, The University of Manchester, Manchester, United Kingdom
- Department of Radiology, Stanford University, Stanford, CA, United States
| | - Peter Warn
- Evotec (UK) Ltd., Manchester Science Park, Manchester, United Kingdom
| | - Andrew Sharp
- Evotec (UK) Ltd., Manchester Science Park, Manchester, United Kingdom
| | - Ellie Burgess
- Evotec (UK) Ltd., Manchester Science Park, Manchester, United Kingdom
| | - Emad Moeendarbary
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
- Department of Mechanical Engineering, University College London, London, United Kingdom
| | - Kumlesh K. Dev
- Drug Development, Department of Physiology, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Graham K. Sheridan
- Neuroimmulology & Neurotherapeutics Laboratory, School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, United Kingdom
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Wen YQ, Gao X, Wang A, Yang Y, Liu S, Yu Z, Song GB, Zhao HC. Substrate stiffness affects neural network activity in an extracellular matrix proteins dependent manner. Colloids Surf B Biointerfaces 2018; 170:729-735. [DOI: 10.1016/j.colsurfb.2018.03.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/23/2018] [Accepted: 03/24/2018] [Indexed: 12/15/2022]
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15
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David J, O'Toole E, O'Reilly K, Thuery G, Assmann N, Finlay D, Harkin A. Inhibitors of the NMDA-Nitric Oxide Signaling Pathway Protect Against Neuronal Atrophy and Synapse Loss Provoked by l-alpha Aminoadipic Acid-treated Astrocytes. Neuroscience 2018; 392:38-56. [PMID: 30267830 DOI: 10.1016/j.neuroscience.2018.09.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 09/06/2018] [Accepted: 09/17/2018] [Indexed: 01/01/2023]
Abstract
The impact of treating astrocytes with the astrocytic toxin l-alpha amino adipic acid (L-AAA) on neuronal outgrowth, complexity and synapse formation was assessed, using a model of astrocyte-neuronal interaction. Treatment of rat primary cortical neurons with conditioned media (CM) derived from astrocytes treated with L-AAA reduced neuronal complexity and synapse formation. L-AAA provoked a reduction in the expression of glial fibrillary acid protein (GFAP) and a reduction in ATP-linked mitochondrial respiration in astrocytic cells. As the NMDA-R/PSD-95/NOS signaling pathway is implicated in regulating the structural plasticity of neurons, treatment of neuronal cultures with the neuronal nitric oxide synthase (nNOS) inhibitor 1-[2-(trifluoromethyl)phenyl] imidazole (TRIM) [100 nM] was assessed and observed to protect against L-AAA-treated astrocytic CM-induced reduction in neuronal complexity and synapse loss. Treatment with the NMDA-R antagonist ketamine protected against the CM-induced loss of synapse formation whereas the novel PSD-95/nNOS inhibitors 2-((1H-benzo[d] [1,2,3]triazol-5-ylamino) methyl)-4,6-dichlorophenol (IC87201) and 4-(3,5-dichloro-2-hydroxy-benzylamino)-2-hydroxybenzoic acid (ZL006) protected against synapse loss with partial protection against reduced neurite outgrowth. Furthermore, L-AAA delivery to the pre-limbic cortex (PLC) of mice was found to increase dendritic spine density and treatment with ZL006 reduced this effect. In summary, L-AAA-induced astrocyte impairment leads to a loss of neuronal complexity and synapse loss in vitro and increased dendritic spine density in vivo that may be reversed by inhibitors of the NMDA-R/PSD-95/NOS pathway. The results have implications for understanding astrocytic-neuronal interaction and the search for drug candidates that may provide therapeutic approaches for brain disorders associated with astrocytic histopathology.
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Affiliation(s)
- J David
- Trinity College Institute of Neuroscience & School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland.
| | - E O'Toole
- Trinity College Institute of Neuroscience & School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland.
| | - K O'Reilly
- Trinity College Institute of Neuroscience & School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland.
| | - G Thuery
- Trinity College Institute of Neuroscience & School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland
| | - N Assmann
- Trinity Biomedical Sciences Institute, School of Biochemistry and Immunology & School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland.
| | - D Finlay
- Trinity Biomedical Sciences Institute, School of Biochemistry and Immunology & School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland.
| | - A Harkin
- Trinity College Institute of Neuroscience & School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland.
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16
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Evans EB, Brady SW, Tripathi A, Hoffman-Kim D. Schwann cell durotaxis can be guided by physiologically relevant stiffness gradients. Biomater Res 2018; 22:14. [PMID: 29780613 PMCID: PMC5948700 DOI: 10.1186/s40824-018-0124-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 04/13/2018] [Indexed: 12/21/2022] Open
Abstract
Background Successful nerve regeneration depends upon directed migration of morphologically specialized repair state Schwann cells across a nerve defect. Although several groups have studied directed migration of Schwann cells in response to chemical or topographic cues, the current understanding of how the mechanical environment influences migration remains largely understudied and incomplete. Therefore, the focus of this study was to evaluate Schwann cell migration and morphodynamics in the presence of stiffness gradients, which revealed that Schwann cells can follow extracellular gradients of increasing stiffness, in a form of directed migration termed durotaxis. Methods Polyacrylamide substrates were fabricated to mimic the range of stiffness found in peripheral nerve tissue. We assessed Schwann cell response to substrates that were either mechanically uniform or embedded with a shallow or steep stiffness gradient, respectively corresponding to the mechanical niche present during either the fluid phase or subsequent matrix phase of the peripheral nerve regeneration process. We examined cell migration (velocity and directionality) and morphology (elongation, spread area, nuclear aspect ratio, and cell process dynamics). We also characterized the surface morphology of Schwann cells by scanning electron microscopy. Results On laminin-coated polyacrylamide substrates embedded with either a shallow (∼0.04 kPa/mm) or steep (∼0.95 kPa/mm) stiffness gradient, Schwann cells displayed durotaxis, increasing both their speed and directionality along the gradient materials, fabricated with elastic moduli in the range found in peripheral nerve tissue. Uniquely and unlike cell behavior reported in other cell types, the durotactic response of Schwann cells was not dependent upon the slope of the gradient. When we examined whether durotaxis behavior was accompanied by a pro-regenerative Schwann cell phenotype, we observed altered cell morphology, including increases in spread area and the number, elongation, and branching of the cellular processes, on the steep but not the shallow gradient materials. This phenotype emerged within hours of the cells adhering to the materials and was sustained throughout the 24 hour duration of the experiment. Control experiments also showed that unlike most adherent cells, Schwann cells did not alter their morphology in response to uniform substrates of different stiffnesses. Conclusion This study is notable in its report of durotaxis of cells in response to a stiffness gradient slope, which is greater than an order of magnitude less than reported elsewhere in the literature, suggesting Schwann cells are highly sensitive detectors of mechanical heterogeneity. Altogether, this work identifies durotaxis as a new migratory modality in Schwann cells, and further shows that the presence of a steep stiffness gradient can support a pro-regenerative cell morphology. Electronic supplementary material The online version of this article (10.1186/s40824-018-0124-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elisabeth B Evans
- 1Department of Molecular Pharmacology, Physiology, Brown University, Providence, Rhode Island, 02912 USA
| | - Samantha W Brady
- 1Department of Molecular Pharmacology, Physiology, Brown University, Providence, Rhode Island, 02912 USA
| | - Anubhav Tripathi
- 1Department of Molecular Pharmacology, Physiology, Brown University, Providence, Rhode Island, 02912 USA.,2Center for Biomedical Engineering, Brown University, Providence, Rhode Island, 02912 USA
| | - Diane Hoffman-Kim
- 1Department of Molecular Pharmacology, Physiology, Brown University, Providence, Rhode Island, 02912 USA.,2Center for Biomedical Engineering, Brown University, Providence, Rhode Island, 02912 USA.,3Carney Institute for Brain Science, Brown University, Providence, Rhode Island, 02912 USA.,4Center to Advance Predictive Biology, Brown University, Providence, Rhode Island, 02912 USA
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17
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Svane KC, Asis EK, Omelchenko A, Kunnath AJ, Brzustowicz LM, Silverstein SM, Firestein BL. d-Serine administration affects nitric oxide synthase 1 adaptor protein and DISC1 expression in sex-specific manner. Mol Cell Neurosci 2018; 89:20-32. [PMID: 29601869 DOI: 10.1016/j.mcn.2018.03.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 03/23/2018] [Accepted: 03/25/2018] [Indexed: 01/19/2023] Open
Abstract
Antipsychotic medications are inefficient at treating symptoms of schizophrenia (SCZ), and N-methyl d-aspartate receptor (NMDAR) agonists are potential therapeutic alternatives. As such, these agonists may act on different pathways and proteins altered in the brains of patients with SCZ than do antipsychotic medications. Here, we investigate the effects of administration of the antipsychotic haloperidol and NMDAR agonist d-serine on function and expression of three proteins that play significant roles in SCZ: nitric oxide synthase 1 adaptor protein (NOS1AP), dopamine D2 (D2) receptor, and disrupted in schizophrenia 1 (DISC1). We administered haloperidol or d-serine to male and female Sprague Dawley rats via intraperitoneal injection for 12 days and subsequently examined cortical expression of NOS1AP, D2 receptor, and DISC1. We found sex-specific effects of haloperidol and d-serine treatment on the expression of these proteins. Haloperidol significantly reduced expression of D2 receptor in male, but not female, rats. Conversely, d-serine reduced expression of NOS1AP in male rats and did not affect D2 receptor expression. d-serine treatment also reduced expression of DISC1 in male rats and increased DISC1 expression in female rats. As NOS1AP is overexpressed in the cortex of patients with SCZ and negatively regulates NMDAR signaling, we subsequently examined whether treatment with antipsychotics or NMDAR agonists can reverse the detrimental effects of NOS1AP overexpression in vitro as previously reported by our group. NOS1AP overexpression promotes reduced dendrite branching in vitro, and as such, we treated cortical neurons overexpressing NOS1AP with different antipsychotics (haloperidol, clozapine, fluphenazine) or d-serine for 24 h and determined the effects of these drugs on NOS1AP expression and dendrite branching. While antipsychotics did not affect NOS1AP protein expression or dendrite branching in vitro, d-serine reduced NOS1AP expression and rescued NOS1AP-mediated reductions in dendrite branching. Taken together, our data suggest that d-serine influences the function and expression of NOS1AP, D2 receptor, and DISC1 in a sex-specific manner and reverses the effects of NOS1AP overexpression on dendrite morphology.
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Affiliation(s)
- Kirsten C Svane
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA; Neuroscience Graduate Program, Rutgers, The State University of New Jersey, 675 Hoes Lane West, Piscataway, NJ 08854, USA
| | - Ericka-Kate Asis
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA
| | - Anton Omelchenko
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA; Neuroscience Graduate Program, Rutgers, The State University of New Jersey, 675 Hoes Lane West, Piscataway, NJ 08854, USA
| | - Ansley J Kunnath
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA
| | - Linda M Brzustowicz
- Department of Genetics, Rutgers, The State University of New Jersey, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Steven M Silverstein
- Division of Schizophrenia Research, Rutgers University Behavioral Health Care, 671 Hoes Lane West, Piscataway, NJ 08854, USA
| | - Bonnie L Firestein
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA.
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18
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The hippocampal extracellular matrix regulates pain and memory after injury. Mol Psychiatry 2018; 23:2302-2313. [PMID: 30254235 PMCID: PMC6294737 DOI: 10.1038/s41380-018-0209-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/26/2018] [Accepted: 06/18/2018] [Indexed: 12/11/2022]
Abstract
Chronic pain poses a heavy burden for the individual and society, comprising personal suffering, comorbid psychiatric symptoms, cognitive decline, and disability. Treatment options are poor due in large part to pain centralization, where an initial injury can result in lasting CNS maladaptations. Hippocampal cellular plasticity in chronic pain has become a focus of study due to its roles in cognition, memory, and the experience of pain itself. However, the extracellular alterations that parallel and facilitate changes in hippocampal function have not been addressed to date. Here we show structural and biochemical plasticity in the hippocampal extracellular matrix (ECM) that is linked to behavioral, cellular, and synaptic changes in a mouse model of chronic pain. Specifically, we report deficits in working location memory that are associated with decreased hippocampal dendritic complexity, altered ECM microarchitecture, decreased ECM rigidity, and changes in the levels of key ECM components and enzymes, including increased levels of MMP8. We also report aberrations in long-term potentiation (LTP) and a loss of inhibitory interneuron perineuronal ECM nets, potentially accounting for the aberrations in LTP. Finally, we demonstrate that MMP8 is upregulated after injury and that its genetic downregulation normalizes the behavioral, electrophysiological, and extracellular alterations. By linking specific extracellular changes to the chronic pain phenotype, we provide a novel mechanistic understanding of pain centralization that provides new targets for the treatment of chronic pain.
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19
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Weber IP, Yun SH, Scarcelli G, Franze K. The role of cell body density in ruminant retina mechanics assessed by atomic force and Brillouin microscopy. Phys Biol 2017; 14:065006. [PMID: 28406094 DOI: 10.1088/1478-3975/aa6d18] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Cells in the central nervous system (CNS) respond to the stiffness of their environment. CNS tissue is mechanically highly heterogeneous, thus providing motile cells with region-specific mechanical signals. While CNS mechanics has been measured with a variety of techniques, reported values of tissue stiffness vary greatly, and the morphological structures underlying spatial changes in tissue stiffness remain poorly understood. We here exploited two complementary techniques, contact-based atomic force microscopy and contact-free Brillouin microscopy, to determine the mechanical properties of ruminant retinae, which are built up by different tissue layers. As in all vertebrate retinae, layers of high cell body densities ('nuclear layers') alternate with layers of low cell body densities ('plexiform layers'). Different tissue layers varied significantly in their mechanical properties, with the photoreceptor layer being the stiffest region of the retina, and the inner plexiform layer belonging to the softest regions. As both techniques yielded similar results, our measurements allowed us to calibrate the Brillouin microscopy measurements and convert the Brillouin shift into a quantitative assessment of elastic tissue stiffness with optical resolution. Similar as in the mouse spinal cord and the developing Xenopus brain, we found a strong correlation between nuclear densities and tissue stiffness. Hence, the cellular composition of retinae appears to strongly contribute to local tissue stiffness, and Brillouin microscopy shows a great potential for the application in vivo to measure the mechanical properties of transparent tissues.
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Affiliation(s)
- Isabell P Weber
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
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20
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Rosso G, Young P, Shahin V. Implications of Schwann Cells Biomechanics and Mechanosensitivity for Peripheral Nervous System Physiology and Pathophysiology. Front Mol Neurosci 2017; 10:345. [PMID: 29118694 PMCID: PMC5660964 DOI: 10.3389/fnmol.2017.00345] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/11/2017] [Indexed: 12/21/2022] Open
Abstract
The presence of bones around the central nervous system (CNS) provides it with highly effective physiologically crucial mechanical protection. The peripheral nervous system (PNS), in contrast, lacks this barrier. Consequently, the long held belief is that the PNS is mechanically vulnerable. On the other hand, the PNS is exposed to a variety of physiological mechanical stresses during regular daily activities. This fact prompts us to question the dogma of PNS mechanical vulnerability. As a matter of fact, impaired mechanics of PNS nerves is associated with neuropathies with the liability to mechanical stresses paralleled by significant impairment of PNS physiological functions. Our recent biomechanical integrity investigations on nerve fibers from wild-type and neuropathic mice lend strong support in favor of natural mechanical protection of the PNS and demonstrate a key role of Schwann cells (SCs) therein. Moreover, recent works point out that SCs can sense mechanical properties of their microenvironment and the evidence is growing that SCs mechanosensitivity is important for PNS development and myelination. Hence, SCs exhibit mechanical strength necessary for PNS mechanoprotection as well as mechanosensitivity necessary for PNS development and myelination. This mini review reflects on the intriguing dual ability of SCs and implications for PNS physiology and pathophysiology.
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Affiliation(s)
- Gonzalo Rosso
- Institute of Physiology II, University of Münster, Münster, Germany
| | - Peter Young
- Department of Sleep Medicine and Neuromuscular Disorders, University of Münster, Münster, Germany
| | - Victor Shahin
- Institute of Physiology II, University of Münster, Münster, Germany
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21
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Lantoine J, Grevesse T, Villers A, Delhaye G, Mestdagh C, Versaevel M, Mohammed D, Bruyère C, Alaimo L, Lacour SP, Ris L, Gabriele S. Matrix stiffness modulates formation and activity of neuronal networks of controlled architectures. Biomaterials 2016; 89:14-24. [DOI: 10.1016/j.biomaterials.2016.02.041] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Revised: 02/14/2016] [Accepted: 02/23/2016] [Indexed: 11/16/2022]
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22
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Previtera ML, Sengupta A. Substrate Stiffness Regulates Proinflammatory Mediator Production through TLR4 Activity in Macrophages. PLoS One 2015; 10:e0145813. [PMID: 26710072 PMCID: PMC4692401 DOI: 10.1371/journal.pone.0145813] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 12/09/2015] [Indexed: 01/06/2023] Open
Abstract
Clinical data show that disease adversely affects tissue elasticity or stiffness. While macrophage activity plays a critical role in driving disease pathology, there are limited data available on the effects of tissue stiffness on macrophage activity. In this study, the effects of substrate stiffness on inflammatory mediator production by macrophages were investigated. Bone marrow-derived macrophages were grown on polyacrylamide gels that mimicked the stiffness of a variety of soft biological tissues. Overall, macrophages grown on soft substrates produced less proinflammatory mediators than macrophages grown on stiff substrates when the endotoxin LPS was added to media. In addition, the pathways involved in stiffness-regulated proinflammation were investigated. The TLR4 signaling pathway was examined by evaluating TLR4, p-NF-κB p65, MyD88, and p-IκBα expression as well as p-NF-κB p65 translocation. Expression and translocation of the various signaling molecules were higher in macrophages grown on stiff substrates than on soft substrates. Furthermore, TLR4 knockout experiments showed that TLR4 activity enhanced proinflammation on stiff substrates. In conclusion, these results suggest that proinflammatory mediator production initiated by TLR4 is mechanically regulated in macrophages.
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Affiliation(s)
- Michelle L. Previtera
- JFK Neuroscience Institute, JFK Medical Center, 65 James Street, Edison, New Jersey, 08820, United States of America
- Department of Neuroscience, Seton Hall University, 400 South Orange Avenue, South Orange, New Jersey, 07079, United States of America
| | - Amitabha Sengupta
- JFK Neuroscience Institute, JFK Medical Center, 65 James Street, Edison, New Jersey, 08820, United States of America
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23
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Polackwich RJ, Koch D, McAllister R, Geller HM, Urbach JS. Traction force and tension fluctuations in growing axons. Front Cell Neurosci 2015; 9:417. [PMID: 26578882 PMCID: PMC4624864 DOI: 10.3389/fncel.2015.00417] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 10/02/2015] [Indexed: 01/07/2023] Open
Abstract
Actively generated mechanical forces play a central role in axon growth and guidance, but the mechanisms that underly force generation and regulation in growing axons remain poorly understood. We report measurements of the dynamics of traction stresses from growth cones of actively advancing axons from postnatal rat DRG neurons. By tracking the movement of the growth cone and analyzing the traction stress field from a reference frame that moves with it, we are able to show that there is a clear and consistent average stress field that underlies the complex spatial stresses present at any one time. The average stress field has strong maxima on the sides of the growth cone, directed inward toward the growth cone neck. This pattern represents a contractile stress contained within the growth cone, and a net force that is balanced by the axon tension. Using high time-resolution measurements of the growth cone traction stresses, we show that the stress field is composed of fluctuating local stress peaks, with a large number peaks that live for a short time, a population of peaks whose lifetime distribution follows an exponential decay, and a small number of very long-lived peaks. We show that the high time-resolution data also reveal that the tension appears to vary randomly over short time scales, roughly consistent with the lifetime of the stress peaks, suggesting that the tension fluctuations originate from stochastic adhesion dynamics.
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Affiliation(s)
- Robert J Polackwich
- Department of Physics and The Institute for Soft Matter Synthesis and Metrology, Georgetown University Washington, DC, USA
| | - Daniel Koch
- Department of Physics and The Institute for Soft Matter Synthesis and Metrology, Georgetown University Washington, DC, USA
| | - Ryan McAllister
- Department of Physics and The Institute for Soft Matter Synthesis and Metrology, Georgetown University Washington, DC, USA
| | - Herbert M Geller
- Developmental Neurobiology Section, Cell Biology and Physiology Center, National Heart, Lung, and Blood Institute, National Institutes of Health Bethesda, MD, USA
| | - Jeffrey S Urbach
- Department of Physics and The Institute for Soft Matter Synthesis and Metrology, Georgetown University Washington, DC, USA
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24
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Previtera ML, Firestein BL. Glutamate affects dendritic morphology of neurons grown on compliant substrates. Biotechnol Prog 2015; 31:1128-32. [PMID: 25827105 DOI: 10.1002/btpr.2085] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 03/25/2015] [Indexed: 12/26/2022]
Abstract
Brain stiffness changes in response to injury or disease. As a secondary consequence, glutamate is released from neurons and astroglia. Two types of glutamate receptors, N-methyl-d-aspartate (NMDA) and α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, sense mechanotransduction, leading to downstream signaling in neurons. Recently, our group reported that these two receptors affect dendrite morphology in hippocampal neurons grown on compliant substrates. Blocking receptor activity has distinct effects on dendrites, depending on whether neurons are grown on soft or stiff gels. In the current study, we examine whether exposure to glutamate itself alters stiffness-mediated changes to dendrites in hippocampal neurons. We find that glutamate augments changes seen when neurons are grown on soft gels of 300 or 600 Pa, but in contrast, glutamate attenuates changes seen when neurons are grown on stiff gels of 3,000 Pa. These results suggest that there is interplay between mechanosensing and glutamate receptor activation in determining dendrite morphology in neurons.
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Affiliation(s)
- Michelle L Previtera
- Graduate Program in Molecular Biosciences, the State University of New Jersey, Piscataway, NJ, 08854-8082.,Dept. of Cell Biology and Neuroscience, the State University of New Jersey, Piscataway, NJ, 08854-8082
| | - Bonnie L Firestein
- Dept. of Cell Biology and Neuroscience, the State University of New Jersey, Piscataway, NJ, 08854-8082.,Dept. of Biomedical Engineering, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854-8082
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Sridharan A, Nguyen JK, Capadona JR, Muthuswamy J. Compliant intracortical implants reduce strains and strain rates in brain tissue in vivo. J Neural Eng 2015; 12:036002. [PMID: 25834105 DOI: 10.1088/1741-2560/12/3/036002] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE The objective of this research is to characterize the mechanical interactions of (1) soft, compliant and (2) non-compliant implants with the surrounding brain tissue in a rodent brain. Understanding such interactions will enable the engineering of novel materials that will improve stability and reliability of brain implants. APPROACH Acute force measurements were made using a load cell in n = 3 live rats, each with 4 craniotomies. Using an indentation method, brain tissue was tested for changes in force using established protocols. A total of 4 non-compliant, bare silicon microshanks, 3 non-compliant polyvinyl acetate (PVAc)-coated silicon microshanks, and 6 compliant, nanocomposite microshanks were tested. Stress values were calculated by dividing the force by surface area and strain was estimated using a linear stress-strain relationship. Micromotion effects from breathing and vascular pulsatility on tissue stress were estimated from a 5 s interval of steady-state measurements. Viscoelastic properties were estimated using a second-order Prony series expansion of stress-displacement curves for each shank. MAIN RESULTS The distribution of strain values imposed on brain tissue for both compliant nanocomposite microshanks and PVAc-coated, non-compliant silicon microshanks were significantly lower compared to non-compliant bare silicon shanks. Interestingly, step-indentation experiments also showed that compliant, nanocomposite materials significantly decreased stress relaxation rates in the brain tissue at the interface (p < 0.05) compared to non-compliant silicon and PVAc-coated silicon materials. Furthermore, both PVAc-coated non-compliant silicon and compliant nanocomposite shanks showed significantly reduced (by 4-5 fold) stresses due to tissue micromotion at the interface. SIGNIFICANCE The results of this study showed that soft, adaptive materials reduce strains and strain rates and micromotion induced stresses in the surrounding brain tissue. Understanding the material behavior at the site of tissue contact will help to improve neural implant design.
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Affiliation(s)
- Arati Sridharan
- School of Biological & Health Systems Engineering, Ira A. Fulton School of Engineering, Arizona State University, Tempe, AZ 85287, USA
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Previtera ML, Peterman K, Shah S, Luzuriaga J. Lipid rafts direct macrophage motility in the tissue microenvironment. Ann Biomed Eng 2014; 43:896-905. [PMID: 25269613 DOI: 10.1007/s10439-014-1142-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 09/23/2014] [Indexed: 01/14/2023]
Abstract
Infiltrating leukocytes are exposed to a wide range of tissue elasticities. While we know the effects of substrate elasticity on acute inflammation via the study of neutrophil migration, we do not know its effects on leukocytes that direct chronic inflammatory events. Here, we studied morphology and motility of macrophages, the innate immune cells that orchestrate acute and chronic inflammation, on polyacrylamide hydrogels that mimicked a wide range of tissue elasticities. As expected, we found that macrophage spreading area increased as substrate elasticity increased. Unexpectedly, we found that morphology did not inversely correlate with motility. In fact, velocity of steady-state macrophages remained unaffected by substrate elasticity, while velocity of biologically stimulated macrophages was limited on stiff substrates. We also found that the lack of motility on stiff substrates was due to a lack of lipid rafts on the leading edge of the macrophages. This study implicates lipid rafts in the mechanosensory mechanism of innate immune cell infiltration.
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Affiliation(s)
- Michelle L Previtera
- JFK Neuroscience Institute, JFK Medical Center, 65 James Street, Edison, NJ, 08820, USA,
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Zhang QY, Zhang YY, Xie J, Li CX, Chen WY, Liu BL, Wu XA, Li SN, Huo B, Jiang LH, Zhao HC. Stiff substrates enhance cultured neuronal network activity. Sci Rep 2014; 4:6215. [PMID: 25163607 PMCID: PMC4147369 DOI: 10.1038/srep06215] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 08/07/2014] [Indexed: 11/09/2022] Open
Abstract
The mechanical property of extracellular matrix and cell-supporting substrates is known to modulate neuronal growth, differentiation, extension and branching. Here we show that substrate stiffness is an important microenvironmental cue, to which mouse hippocampal neurons respond and integrate into synapse formation and transmission in cultured neuronal network. Hippocampal neurons were cultured on polydimethylsiloxane substrates fabricated to have similar surface properties but a 10-fold difference in Young's modulus. Voltage-gated Ca(2+) channel currents determined by patch-clamp recording were greater in neurons on stiff substrates than on soft substrates. Ca(2+) oscillations in cultured neuronal network monitored using time-lapse single cell imaging increased in both amplitude and frequency among neurons on stiff substrates. Consistently, synaptic connectivity recorded by paired recording was enhanced between neurons on stiff substrates. Furthermore, spontaneous excitatory postsynaptic activity became greater and more frequent in neurons on stiff substrates. Evoked excitatory transmitter release and excitatory postsynaptic currents also were heightened at synapses between neurons on stiff substrates. Taken together, our results provide compelling evidence to show that substrate stiffness is an important biophysical factor modulating synapse connectivity and transmission in cultured hippocampal neuronal network. Such information is useful in designing instructive scaffolds or supporting substrates for neural tissue engineering.
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Affiliation(s)
- Quan-You Zhang
- 1] Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China [2] College of Mechanics, Taiyuan University of Technology, China [3]
| | - Yan-Yan Zhang
- 1] Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China [2]
| | - Jing Xie
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| | - Chen-Xu Li
- Medical School, Datong University, China
| | - Wei-Yi Chen
- College of Mechanics, Taiyuan University of Technology, China
| | - Bai-Lin Liu
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| | - Xiao-an Wu
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| | - Shu-Na Li
- Biomechanics and Biomaterials Laboratory, Department of Applied Mechanics, School of Aerospace Engineering, Beijing Institute of Technology, China
| | - Bo Huo
- Biomechanics and Biomaterials Laboratory, Department of Applied Mechanics, School of Aerospace Engineering, Beijing Institute of Technology, China
| | - Lin-Hua Jiang
- 1] School of Biomedical Sciences, University of Leeds, United Kingdom [2] Department of Physiology and Neurobiology, School of Basic Medical Sciences, Xinxiang Medical University, China
| | - Hu-Cheng Zhao
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
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Previtera ML, Langrana NA. Preparation of DNA-crosslinked polyacrylamide hydrogels. J Vis Exp 2014. [PMID: 25226067 DOI: 10.3791/51323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Mechanobiology is an emerging scientific area that addresses the critical role of physical cues in directing cell morphology and function. For example, the effect of tissue elasticity on cell function is a major area of mechanobiology research because tissue stiffness modulates with disease, development, and injury. Static tissue-mimicking materials, or materials that cannot alter stiffness once cells are plated, are predominately used to investigate the effects of tissue stiffness on cell functions. While information gathered from static studies is valuable, these studies are not indicative of the dynamic nature of the cellular microenvironment in vivo. To better address the effects of dynamic stiffness on cell function, we developed a DNA-crosslinked polyacrylamide hydrogel system (DNA gels). Unlike other dynamic substrates, DNA gels have the ability to decrease or increase in stiffness after fabrication without stimuli. DNA gels consist of DNA crosslinks that are polymerized into a polyacrylamide backbone. Adding and removing crosslinks via delivery of single-stranded DNA allows temporal, spatial, and reversible control of gel elasticity. We have shown in previous reports that dynamic modulation of DNA gel elasticity influences fibroblast and neuron behavior. In this report and video, we provide a schematic that describes the DNA gel crosslinking mechanisms and step-by-step instructions on the preparation DNA gels.
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Affiliation(s)
| | - Noshir A Langrana
- Department of Biomedical Engineering, Rutgers University; Department of Mechanical and Aerospace Engineering, Rutgers University
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Chen WH, Cheng SJ, Tzen JTC, Cheng CM, Lin YW. Probing relevant molecules in modulating the neurite outgrowth of hippocampal neurons on substrates of different stiffness. PLoS One 2013; 8:e83394. [PMID: 24386192 PMCID: PMC3875460 DOI: 10.1371/journal.pone.0083394] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 11/04/2013] [Indexed: 11/19/2022] Open
Abstract
Hippocampal neurons play a critical role in learning and memory; however, the effects of environmental mechanical forces on neurite extension and associated underlying mechanisms are largely unexplored, possibly due to difficulties in maintaining central nervous system neurons. Neuron adhesion, neurite length, and mechanotransduction are mainly influenced by the extracellular matrix (ECM), which is often associated with structural scaffolding. In this study, we investigated the relationship between substrate stiffness and hippocampal neurite outgrowth by controlling the ratios of polydimethylsiloxane (PDMS) base to curing agent to create substrates of varying stiffness. Immunostaining results demonstrated that hippocampal neurons have longer neurite elongation in 35:1 PDMS substrate compared those grown on 15:1 PDMS, indicating that soft substrates provide a more optimal stiffness for hippocampal neurons. Additionally, we discovered that pPKCα expression was higher in the 15:1 and 35:1 PDMS groups than in the poly-L-lysine-coated glass group. However, when we used a fibronectin (FN) coating, we found that pFAKy397 and pFAKy925 expression were higher in glass group than in the 15:1 or 35: 1 PDMS groups, but pPKCα and pERK1/2 expression were higher in the 35:1 PDMS group than in the glass group. These results support the hypothesis that environmental stiffness influences hippocampal neurite outgrowth and underlying signaling pathways.
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Affiliation(s)
- Wei-Hsin Chen
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Sin-Jhong Cheng
- Department of Life Science and Institute of Zoology, National Taiwan University, Taipei, Taiwan
| | - Jason T. C. Tzen
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Chao-Min Cheng
- Institute of Nanoengineering and Microsystems, National Tsing Hua University, Hsinchu, Taiwan
| | - Yi-Wen Lin
- Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan
- Acupuncture Research Center, China Medical University, Taichung, Taiwan
- * E-mail:
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Sur S, Newcomb CJ, Webber MJ, Stupp SI. Tuning supramolecular mechanics to guide neuron development. Biomaterials 2013; 34:4749-57. [PMID: 23562052 PMCID: PMC3635952 DOI: 10.1016/j.biomaterials.2013.03.025] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 03/10/2013] [Indexed: 12/30/2022]
Abstract
The mechanical properties of the extracellular matrix (ECM) are known to influence neuronal differentiation and maturation, though the mechanism by which neuronal cells respond to these biophysical cues is not completely understood. Here we design ECM mimics using self-assembled peptide nanofibers, in which fiber rigidity is tailored by supramolecular interactions, in order to investigate the relationship between matrix stiffness and morphological development of hippocampal neurons. We observe that development of neuronal polarity is accelerated on soft nanofiber substrates, and results from the dynamics of neuronal processes. While the total neurite outgrowth of non-polar neurons remains conserved, weaker adhesion of neurites to soft PA substrate facilitates easier retraction, thus enhancing the frequency of "extension-retraction" events. We hypothesize that higher neurite motility enhances the probability of one neurite to reach a critical length relative to others, thereby initiating the developmental sequence of axon differentiation. Our results suggest that substrate stiffness can influence neuronal development by regulating its dynamics, thus providing useful information on scaffold design for applications in neural regeneration.
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Affiliation(s)
- Shantanu Sur
- The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, IL, 60611
| | - Christina J. Newcomb
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208
| | - Matthew J. Webber
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208
| | - Samuel I. Stupp
- The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, IL, 60611
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208
- Department of Chemistry, Northwestern University, Evanston, IL, 60208
- Department of Medicine, Northwestern University, Chicago, IL, 60611
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Abstract
Biological cells are well known to respond to a multitude of chemical signals. In the nervous system, chemical signaling has been shown to be crucially involved in development, normal functioning, and disorders of neurons and glial cells. However, there are an increasing number of studies showing that these cells also respond to mechanical cues. Here, we summarize current knowledge about the mechanical properties of nervous tissue and its building blocks, review recent progress in methodology and understanding of cellular mechanosensitivity in the nervous system, and provide an outlook on the implications of neuromechanics for future developments in biomedical engineering to aid overcoming some of the most devastating and currently incurable CNS pathologies such as spinal cord injuries and multiple sclerosis.
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Affiliation(s)
- Kristian Franze
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK.
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Previtera ML, Hui M, Verma D, Shahin AJ, Schloss R, Langrana NA. The effects of substrate elastic modulus on neural precursor cell behavior. Ann Biomed Eng 2013; 41:1193-207. [PMID: 23429962 DOI: 10.1007/s10439-013-0765-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 02/13/2013] [Indexed: 01/14/2023]
Abstract
The spinal cord has a limited capacity to self-repair. After injury, endogenous stem cells are activated and migrate, proliferate, and differentiate into glial cells. The absence of neuronal differentiation has been partly attributed to the interaction between the injured microenvironment and neural stem cells. In order to improve post-injury neuronal differentiation and/or maturation potential, cell-cell and cell-biochemical interactions have been investigated. However, little is known about the role of stem cell-matrix interactions on stem cell-mediated repair. Here, we specifically examined the effects of matrix elasticity on stem cell-mediated repair in the spinal cord, since spinal cord injury results in drastic changes in parenchyma elasticity and viscosity. Spinal cord-derived neural precursor cells (NPCs) were grown on bis-acrylamide substrates with various rigidities. NPC growth, proliferation, and differentiation were examined and optimal in the range of normal spinal cord elasticity. In conclusion, limitations in NPC growth, proliferation, and neuronal differentiation were encountered when substrate elasticity was not within normal spinal cord tissue elasticity ranges. These studies elucidate the effect injury mediated mechanical changes may have on tissue repair by stem cells. Furthermore, this information can be applied to the development of future neuroregenerative biomaterials for spinal cord repair.
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Affiliation(s)
- Michelle L Previtera
- Department of Biomedical Engineering, Rutgers University, 599 Taylor Road, Piscataway, NJ 08854, USA
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Piezoelectric Substrates Promote Neurite Growth in Rat Spinal Cord Neurons. Ann Biomed Eng 2012; 41:112-22. [DOI: 10.1007/s10439-012-0628-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 07/13/2012] [Indexed: 12/22/2022]
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Affiliation(s)
- Pei-lin Cheng
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan;
| | - Mu-ming Poo
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, California, 94720, USA;
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Polyelectrolyte Complex Membranes for Prevention of Post-Surgical Adhesions in Neurosurgery. Ann Biomed Eng 2012; 40:1949-60. [DOI: 10.1007/s10439-012-0564-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 03/30/2012] [Indexed: 10/28/2022]
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37
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Fibroblast Morphology on Dynamic Softening of Hydrogels. Ann Biomed Eng 2011; 40:1061-72. [DOI: 10.1007/s10439-011-0483-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 11/28/2011] [Indexed: 11/26/2022]
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Man AJ, Davis HE, Itoh A, Leach JK, Bannerman P. Neurite Outgrowth in Fibrin Gels Is Regulated by Substrate Stiffness. Tissue Eng Part A 2011; 17:2931-42. [DOI: 10.1089/ten.tea.2011.0030] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Alan J. Man
- Department of Biomedical Engineering, UC Davis, Davis, California
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children Northern California, Sacramento, California
| | - Hillary E. Davis
- Department of Biomedical Engineering, UC Davis, Davis, California
| | - Aki Itoh
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children Northern California, Sacramento, California
- Department of Neurology, School of Medicine, University of California, Davis, Shriners Hospitals for Children Northern California, Sacramento, California
| | | | - Peter Bannerman
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children Northern California, Sacramento, California
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