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Potekhina Y, Filatova A, Tregubova E, Mokhov D. Mechanosensitivity of Cells and Its Role in the Regulation of Physiological Functions and the Implementation of Physiotherapeutic Effects (Review). Sovrem Tekhnologii Med 2020; 12:77-89. [PMID: 34795996 PMCID: PMC8596276 DOI: 10.17691/stm2020.12.4.10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Indexed: 01/11/2023] Open
Abstract
Regulatory signals in the body are not limited to chemical and electrical ones. There is another type of important signals for cells: those are mechanical signals (coming from the environment or arising from within the body), which have been less known in the literature. The review summarizes new information on the mechanosensitivity of various cells of connective tissue and nervous system. Participation of mechanical stimuli in the regulation of growth, development, differentiation, and functioning of tissues is described. The data focus on bone remodeling, wound healing, neurite growth, and the formation of neural networks. Mechanotransduction, cellular organelles, and mechanosensitive molecules involved in these processes are discussed as well as the role of the extracellular matrix. The importance of mechanical characteristics of cells in the pathogenesis of diseases is highlighted. Finally, the possible role of mechanosensitivity in mediating the physiotherapeutic effects is addressed.
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Affiliation(s)
- Yu.P. Potekhina
- Professor, Department of Normal Physiology named after N.Y. Belenkov; Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
| | - A.I. Filatova
- Student, Faculty of Pediatrics; Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
| | - E.S. Tregubova
- Professor, Department of Osteopathy; North-Western State Medical University named after I.I. Mechnikov, 41 Kirochnaya St., Saint Petersburg, 191015, Russia; Associate Professor, Institute of Osteopathy; Saint Petersburg State University, 7/9 Universitetskaya naberezhnaya, Saint Petersburg, 199034, Russia
| | - D.E. Mokhov
- Head of the Department of Osteopathy; North-Western State Medical University named after I.I. Mechnikov, 41 Kirochnaya St., Saint Petersburg, 191015, Russia; Director of the Institute of Osteopathy Saint Petersburg State University, 7/9 Universitetskaya naberezhnaya, Saint Petersburg, 199034, Russia
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52
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Espinosa-Hoyos D, Burstein SR, Cha J, Jain T, Nijsure M, Jagielska A, Fossati V, Van Vliet KJ. Mechanosensitivity of Human Oligodendrocytes. Front Cell Neurosci 2020; 14:222. [PMID: 32848617 PMCID: PMC7420028 DOI: 10.3389/fncel.2020.00222] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 06/22/2020] [Indexed: 12/28/2022] Open
Abstract
Oligodendrocytes produce and repair myelin, which is critical for the integrity and function of the central nervous system (CNS). Oligodendrocyte and oligodendrocyte progenitor cell (OPC) biology is modulated in vitro by mechanical cues within the magnitudes observed in vivo. In some cases, these cues are sufficient to accelerate or inhibit terminal differentiation of murine oligodendrocyte progenitors. However, our understanding of oligodendrocyte lineage mechanobiology has been restricted primarily to animal models to date, due to the inaccessibility and challenges of human oligodendrocyte cell culture. Here, we probe the mechanosensitivity of human oligodendrocyte lineage cells derived from human induced pluripotent stem cells. We target phenotypically distinct stages of the human oligodendrocyte lineage and quantify the effect of substratum stiffness on cell migration and differentiation, within the range documented in vivo. We find that human oligodendrocyte lineage cells exhibit mechanosensitive migration and differentiation. Further, we identify two patterns of human donor line-dependent mechanosensitive differentiation. Our findings illustrate the variation among human oligodendrocyte responses, otherwise not captured by animal models, that are important for translational research. Moreover, these findings highlight the importance of studying glia under conditions that better approximate in vivo mechanical cues. Despite significant progress in human oligodendrocyte derivation methodology, the extended duration, low yield, and low selectivity of human-induced pluripotent stem cell-derived oligodendrocyte protocols significantly limit the scale-up and implementation of these cells and protocols for in vivo and in vitro applications. We propose that mechanical modulation, in combination with traditional soluble and insoluble factors, provides a key avenue to address these challenges in cell production and in vitro analysis.
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Affiliation(s)
- Daniela Espinosa-Hoyos
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Suzanne R. Burstein
- The New York Stem Cell Foundation Research Institute, New York, NY, United States
| | - Jaaram Cha
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Tanya Jain
- The New York Stem Cell Foundation Research Institute, New York, NY, United States
| | - Madhura Nijsure
- The New York Stem Cell Foundation Research Institute, New York, NY, United States
| | - Anna Jagielska
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
- Critical Analytics for Manufacturing Personalized-Medicine (CAMP) Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology (SMART) CREATE, Singapore, Singapore
| | - Valentina Fossati
- The New York Stem Cell Foundation Research Institute, New York, NY, United States
| | - Krystyn J. Van Vliet
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
- Critical Analytics for Manufacturing Personalized-Medicine (CAMP) Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology (SMART) CREATE, Singapore, Singapore
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
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53
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Hanlon L, Gautam V, Wood JDA, Reddy P, Barson MSJ, Niihori M, Silalahi ARJ, Corry B, Wrachtrup J, Sellars MJ, Daria VR, Maletinsky P, Stuart GJ, Doherty MW. Diamond nanopillar arrays for quantum microscopy of neuronal signals. NEUROPHOTONICS 2020; 7:035002. [PMID: 32775500 PMCID: PMC7406893 DOI: 10.1117/1.nph.7.3.035002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 06/29/2020] [Indexed: 05/05/2023]
Abstract
Significance: Wide-field measurement of cellular membrane dynamics with high spatiotemporal resolution can facilitate analysis of the computing properties of neuronal circuits. Quantum microscopy using a nitrogen-vacancy (NV) center is a promising technique to achieve this goal. Aim: We propose a proof-of-principle approach to NV-based neuron functional imaging. Approach: This goal is achieved by engineering NV quantum sensors in diamond nanopillar arrays and switching their sensing mode to detect the changes in the electric fields instead of the magnetic fields, which has the potential to greatly improve signal detection. Apart from containing the NV quantum sensors, nanopillars also function as waveguides, delivering the excitation/emission light to improve sensitivity. The nanopillars also improve the amplitude of the neuron electric field sensed by the NV by removing screening charges. When the nanopillar array is used as a cell niche, it acts as a cell scaffolds which makes the pillars function as biomechanical cues that facilitate the growth and formation of neuronal circuits. Based on these growth patterns, numerical modeling of the nanoelectromagnetics between the nanopillar and the neuron was also performed. Results: The growth study showed that nanopillars with a 2 - μ m pitch and a 200-nm diameter show ideal growth patterns for nanopillar sensing. The modeling showed an electric field amplitude as high as ≈ 1.02 × 10 10 mV / m at an NV 100 nm from the membrane, a value almost 10 times the minimum field that the NV can detect. Conclusion: This proof-of-concept study demonstrated unprecedented NV sensing potential for the functional imaging of mammalian neuron signals.
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Affiliation(s)
- Liam Hanlon
- Australian National University, Research School of Physics and Engineering, Laser Physics Centre, Canberra, ACT, Australia
| | - Vini Gautam
- Australian National University, John Curtin School of Medical Research, Eccles Institute of Neuroscience, Canberra, ACT, Australia
| | | | - Prithvi Reddy
- Australian National University, Research School of Physics and Engineering, Laser Physics Centre, Canberra, ACT, Australia
| | - Michael S. J. Barson
- Australian National University, Research School of Physics and Engineering, Laser Physics Centre, Canberra, ACT, Australia
| | - Marika Niihori
- Australian National University, Research School of Physics and Engineering, Laser Physics Centre, Canberra, ACT, Australia
| | | | - Ben Corry
- Australian National University, Research School of Biology, Canberra, ACT, Australia
| | - Jörg Wrachtrup
- University of Stuttgart, 3rd Institute of Physics, Stuttgart Research Centre of Photonic Engineering (SCoPE), Stuttgart, Germany
| | - Matthew J. Sellars
- Australian National University, Research School of Physics and Engineering, Laser Physics Centre, Canberra, ACT, Australia
| | - Vincent R. Daria
- Australian National University, John Curtin School of Medical Research, Eccles Institute of Neuroscience, Canberra, ACT, Australia
| | | | - Gregory J. Stuart
- Australian National University, John Curtin School of Medical Research, Eccles Institute of Neuroscience, Canberra, ACT, Australia
| | - Marcus W. Doherty
- Australian National University, Research School of Physics and Engineering, Laser Physics Centre, Canberra, ACT, Australia
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54
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Juncheed K, Kohlstrunk B, Friebe S, Dallacasagrande V, Maurer P, Reichenbach A, Mayr SG, Zink M. Employing Nanostructured Scaffolds to Investigate the Mechanical Properties of Adult Mammalian Retinae Under Tension. Int J Mol Sci 2020; 21:ijms21113889. [PMID: 32485972 PMCID: PMC7313470 DOI: 10.3390/ijms21113889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 05/25/2020] [Accepted: 05/25/2020] [Indexed: 12/01/2022] Open
Abstract
Numerous eye diseases are linked to biomechanical dysfunction of the retina. However, the underlying forces are almost impossible to quantify experimentally. Here, we show how biomechanical properties of adult neuronal tissues such as porcine retinae can be investigated under tension in a home-built tissue stretcher composed of nanostructured TiO2 scaffolds coupled to a self-designed force sensor. The employed TiO2 nanotube scaffolds allow for organotypic long-term preservation of adult tissues ex vivo and support strong tissue adhesion without the application of glues, a prerequisite for tissue investigations under tension. In combination with finite element calculations we found that the deformation behavior is highly dependent on the displacement rate which results in Young’s moduli of (760–1270) Pa. Image analysis revealed that the elastic regime is characterized by a reversible shear deformation of retinal layers. For larger deformations, tissue destruction and sliding of retinal layers occurred with an equilibration between slip and stick at the interface of ruptured layers, resulting in a constant force during stretching. Since our study demonstrates how porcine eyes collected from slaughterhouses can be employed for ex vivo experiments, our study also offers new perspectives to investigate tissue biomechanics without excessive animal experiments.
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Affiliation(s)
- Kantida Juncheed
- Soft Matter Physics Division and Biotechnology & Biomedical Group, Peter-Debye-Institute for Soft Matter Physics, Leipzig University, Linnéstr. 5, 04103 Leipzig, Germany; (K.J.); (B.K.); (V.D.)
- Paul Flechsig Institute for Brain Research, Leipzig University, Liebigstr. 19, 04103 Leipzig, Germany;
| | - Bernd Kohlstrunk
- Soft Matter Physics Division and Biotechnology & Biomedical Group, Peter-Debye-Institute for Soft Matter Physics, Leipzig University, Linnéstr. 5, 04103 Leipzig, Germany; (K.J.); (B.K.); (V.D.)
| | - Sabrina Friebe
- Division of Surface Physics, Department of Physics and Earth Sciences, Leipzig University and Leibniz Institute of Surface Engineering (IOM), Permoser Str. 15, 04318 Leipzig, Germany; (S.F.); (S.G.M.)
| | - Valentina Dallacasagrande
- Soft Matter Physics Division and Biotechnology & Biomedical Group, Peter-Debye-Institute for Soft Matter Physics, Leipzig University, Linnéstr. 5, 04103 Leipzig, Germany; (K.J.); (B.K.); (V.D.)
- Paul Flechsig Institute for Brain Research, Leipzig University, Liebigstr. 19, 04103 Leipzig, Germany;
| | - Patric Maurer
- Institute of Food Hygiene, Faculty of Veterinary Medicine, Leipzig University, Augustusplatz 10, 04109 Leipzig, Germany;
| | - Andreas Reichenbach
- Paul Flechsig Institute for Brain Research, Leipzig University, Liebigstr. 19, 04103 Leipzig, Germany;
| | - Stefan G. Mayr
- Division of Surface Physics, Department of Physics and Earth Sciences, Leipzig University and Leibniz Institute of Surface Engineering (IOM), Permoser Str. 15, 04318 Leipzig, Germany; (S.F.); (S.G.M.)
| | - Mareike Zink
- Soft Matter Physics Division and Biotechnology & Biomedical Group, Peter-Debye-Institute for Soft Matter Physics, Leipzig University, Linnéstr. 5, 04103 Leipzig, Germany; (K.J.); (B.K.); (V.D.)
- Correspondence: ; Tel.: +49-(341)-9732573; Fax: +49-(341)-9732479
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55
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Extremely Low Forces Induce Extreme Axon Growth. J Neurosci 2020; 40:4997-5007. [PMID: 32444384 DOI: 10.1523/jneurosci.3075-19.2020] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 04/16/2020] [Accepted: 04/21/2020] [Indexed: 12/27/2022] Open
Abstract
Stretch-growth has been defined as a process that extends axons via the application of mechanical forces. In the present article, we used a protocol based on magnetic nanoparticles (NPs) for labeling the entire axon tract of hippocampal neurons, and an external magnetic field gradient to generate a dragging force. We found that the application of forces below 10 pN induces growth at a rate of 0.66 ± 0.02 µm h-1 pN-1 Calcium imaging confirmed the strong increase in elongation rate, in comparison with the condition of tip-growth. Enhanced growth in stretched axons was also accompanied by endoplasmic reticulum (ER) accumulation and, accordingly, it was blocked by an inhibition of translation. Stretch-growth was also found to stimulate axonal branching, glutamatergic synaptic transmission, and neuronal excitability. Moreover, stretched axons showed increased microtubule (MT) density and MT assembly was key to sustaining stretch-growth, suggesting a possible role of tensile forces in MT translocation/assembly. Additionally, our data showed that stretched axons do not respond to BDNF signaling, suggesting interference between the two pathways. As these extremely low mechanical forces are physiologically relevant, stretch-growth could be an important endogenous mechanism of axon growth, with a potential for designing novel strategies for axonal regrowth.SIGNIFICANCE STATEMENT Axon growth involves motion, and motion is driven by forces. The growth cone (GC) itself can generate very low intracellular forces by inducing a drastic cytoskeleton remodeling, in response to signaling molecules. Here, we investigated the key role of intracellular force as an endogenous regulator of axon outgrowth, which it has been neglected for decades because of the lack of methodologies to investigate the topic. Our results indicate a critical role of force in promoting axon growth by facilitating microtubule (MT) polymerization.
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56
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Seo J, Youn W, Choi JY, Cho H, Choi H, Lanara C, Stratakis E, Choi IS. Neuro-taxis: Neuronal movement in gradients of chemical and physical environments. Dev Neurobiol 2020; 80:361-377. [PMID: 32304173 DOI: 10.1002/dneu.22749] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 04/13/2020] [Indexed: 12/15/2022]
Abstract
Environmental chemical and physical cues dynamically interact with migrating neurons and sprouting axons, and in particular, the gradients of environmental cues are regarded as one of the factors intimately involved in the neuronal movement. Since a growth cone was first described by Cajal, more than one century ago, chemical gradients have been suggested as one of the mechanisms by which the neurons determine proper paths and destinations. However, the gradients of physical cues, such as stiffness and topography, which also interact constantly with the neurons and their axons as a component of the extracellular environments, have rarely been noted regarding the guidance of neurons, despite their gradually increasingly reported influences in the case of nonneuronal-cell migration. In this review, we discuss chemical (i.e., chemo- and hapto-) and physical (i.e., duro-) taxis phenomena on the movement of neurons including axonal elongation. In addition, we suggest topotaxis, the most recently proposed physical-taxis phenomenon, as another potential mechanism in the neuronal movement, based on the reports of neuronal recognition of and responses to nanotopography.
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Affiliation(s)
| | - Wongu Youn
- Department of Chemistry, KAIST, Daejeon, Korea
| | - Ji Yu Choi
- Department of Chemistry, KAIST, Daejeon, Korea
| | | | | | - Christina Lanara
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), Heraklion, Crete, Greece
| | - Emmanuel Stratakis
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), Heraklion, Crete, Greece.,Physics Department, University of Crete, Heraklion, Crete, Greece
| | - Insung S Choi
- Department of Chemistry, KAIST, Daejeon, Korea.,Department of Bio and Brain Engineering, KAIST, Daejeon, Korea
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57
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Bonnesœur S, Morin‐Grognet S, Thoumire O, Le Cerf D, Boyer O, Vannier J, Labat B. Hyaluronan‐based hydrogels as versatile tumor‐like models: Tunable ECM and stiffness with genipin‐crosslinking. J Biomed Mater Res A 2020; 108:1256-1268. [DOI: 10.1002/jbm.a.36899] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 02/08/2020] [Accepted: 02/10/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Sarah Bonnesœur
- Normandie Université, INSERM, U1234, Faculté de Médecine et Pharmacie, UNIROUEN Rouen France
| | - Sandrine Morin‐Grognet
- Normandie Université, PBS UMR 6270, UFR de Sciences et Techniques, FR3038, UNIROUEN, INSA Rouen, CNRS Evreux Cedex France
| | - Olivier Thoumire
- Normandie Université, PBS UMR 6270, UFR de Sciences et Techniques, FR3038, UNIROUEN, INSA Rouen, CNRS Evreux Cedex France
| | - Didier Le Cerf
- Normandie Université, PBS UMR 6270, UFR de Sciences et Techniques, FR3038, UNIROUEN, INSA Rouen, CNRS Rouen France
| | - Olivier Boyer
- Normandie Université, INSERM, U1234, Faculté de Médecine et Pharmacie, UNIROUEN Rouen France
| | - Jean‐Pierre Vannier
- Normandie Université, INSERM, U1234, Faculté de Médecine et Pharmacie, UNIROUEN Rouen France
| | - Béatrice Labat
- Normandie Université, PBS UMR 6270, UFR de Sciences et Techniques, FR3038, UNIROUEN, INSA Rouen, CNRS Evreux Cedex France
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58
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Maturo MG, Soligo M, Gibson G, Manni L, Nardini C. The greater inflammatory pathway-high clinical potential by innovative predictive, preventive, and personalized medical approach. EPMA J 2020; 11:1-16. [PMID: 32140182 PMCID: PMC7028895 DOI: 10.1007/s13167-019-00195-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 11/13/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND LIMITATIONS Impaired wound healing (WH) and chronic inflammation are hallmarks of non-communicable diseases (NCDs). However, despite WH being a recognized player in NCDs, mainstream therapies focus on (un)targeted damping of the inflammatory response, leaving WH largely unaddressed, owing to three main factors. The first is the complexity of the pathway that links inflammation and wound healing; the second is the dual nature, local and systemic, of WH; and the third is the limited acknowledgement of genetic and contingent causes that disrupt physiologic progression of WH. PROPOSED APPROACH Here, in the frame of Predictive, Preventive, and Personalized Medicine (PPPM), we integrate and revisit current literature to offer a novel systemic view on the cues that can impact on the fate (acute or chronic inflammation) of WH, beyond the compartmentalization of medical disciplines and with the support of advanced computational biology. CONCLUSIONS This shall open to a broader understanding of the causes for WH going awry, offering new operational criteria for patients' stratification (prediction and personalization). While this may also offer improved options for targeted prevention, we will envisage new therapeutic strategies to reboot and/or boost WH, to enable its progression across its physiological phases, the first of which is a transient acute inflammatory response versus the chronic low-grade inflammation characteristic of NCDs.
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Affiliation(s)
- Maria Giovanna Maturo
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila, Italy
| | - Marzia Soligo
- Institute of Translational Pharmacology, Consiglio Nazionale delle Ricerche (CNR), Rome, Italy
| | - Greg Gibson
- Center for Integrative Genomics, School of Biological Sciences, Georgia Tech, Atlanta, GA USA
| | - Luigi Manni
- Institute of Translational Pharmacology, Consiglio Nazionale delle Ricerche (CNR), Rome, Italy
| | - Christine Nardini
- IAC Institute for Applied Computing, Consiglio Nazionale delle Ricerche (CNR), Rome, Italy
- Bio Unit, Scientific and Medical Direction, SOL Group, Monza, Italy
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59
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Dudiki T, Meller J, Mahajan G, Liu H, Zhevlakova I, Stefl S, Witherow C, Podrez E, Kothapalli CR, Byzova TV. Microglia control vascular architecture via a TGFβ1 dependent paracrine mechanism linked to tissue mechanics. Nat Commun 2020; 11:986. [PMID: 32080187 PMCID: PMC7033106 DOI: 10.1038/s41467-020-14787-y] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 02/01/2020] [Indexed: 01/13/2023] Open
Abstract
Tissue microarchitecture and mechanics are important in development and pathologies of the Central Nervous System (CNS); however, their coordinating mechanisms are unclear. Here, we report that during colonization of the retina, microglia contacts the deep layer of high stiffness, which coincides with microglial bipolarization, reduction in TGFβ1 signaling and termination of vascular growth. Likewise, stiff substrates induce microglial bipolarization and diminish TGFβ1 expression in hydrogels. Both microglial bipolarization in vivo and the responses to stiff substrates in vitro require intracellular adaptor Kindlin3 but not microglial integrins. Lack of Kindlin3 causes high microglial contractility, dysregulation of ERK signaling, excessive TGFβ1 expression and abnormally-patterned vasculature with severe malformations in the area of photoreceptors. Both excessive TGFβ1 signaling and vascular defects caused by Kindlin3-deficient microglia are rescued by either microglial depletion or microglial knockout of TGFβ1 in vivo. This mechanism underlies an interplay between microglia, vascular patterning and tissue mechanics within the CNS.
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Affiliation(s)
- Tejasvi Dudiki
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Julia Meller
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Gautam Mahajan
- Chemical and Biomedical Engineering Department, Washkewicz College of Engineering, Cleveland State University, Cleveland, OH, USA
| | - Huan Liu
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Irina Zhevlakova
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Samantha Stefl
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.,Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Conner Witherow
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.,Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Eugene Podrez
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Chandrasekhar R Kothapalli
- Chemical and Biomedical Engineering Department, Washkewicz College of Engineering, Cleveland State University, Cleveland, OH, USA
| | - Tatiana V Byzova
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.
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60
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Wan Z, Zhang P, Liu Y, Lv L, Zhou Y. Four-dimensional bioprinting: Current developments and applications in bone tissue engineering. Acta Biomater 2020; 101:26-42. [PMID: 31672585 DOI: 10.1016/j.actbio.2019.10.038] [Citation(s) in RCA: 157] [Impact Index Per Article: 39.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 10/20/2019] [Accepted: 10/25/2019] [Indexed: 12/21/2022]
Abstract
Four-dimensional (4D) bioprinting, in which the concept of time is integrated with three-dimensional (3D) bioprinting as the fourth dimension, has currently emerged as the next-generation solution of tissue engineering as it presents the possibility of constructing complex, functional structures. 4D bioprinting can be used to fabricate dynamic 3D-patterned biological architectures that will change their shapes under various stimuli by employing stimuli-responsive materials. The functional transformation and maturation of printed cell-laden constructs over time are also regarded as 4D bioprinting, providing unprecedented potential for bone tissue engineering. The shape memory properties of printed structures cater to the need for personalized bone defect repair and the functional maturation procedures promote the osteogenic differentiation of stem cells. In this review, we introduce the application of different stimuli-responsive biomaterials in tissue engineering and a series of 4D bioprinting strategies based on functional transformation of printed structures. Furthermore, we discuss the application of 4D bioprinting in bone tissue engineering, as well as the current challenges and future perspectives. STATEMENTS OF SIGNIFICANCE: In this review, we have demonstrated the 4D bioprinting technologies, which integrate the concept of time within the traditional 3D bioprinting technology as the fourth dimension and facilitate the fabrications of complex, functional biological architectures. These 4D bioprinting structures could go through shape or functional transformation over time via using different stimuli-responsive biomaterials and a series of 4D bioprinting strategies. Moreover, by summarizing potential applications of 4D bioprinting in the field of bone tissue engineering, these emerging technologies could fulfill unaddressed medical requirements. The further discussions about future challenges and perspectives will give us more inspirations about widespread applications of this emerging technology for tissue engineering in biomedical field.
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Affiliation(s)
- Zhuqing Wan
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, National Clinical Research Center for Oral Diseases, Beijing Key Laboratory of Digital Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081, PR China
| | - Ping Zhang
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, National Clinical Research Center for Oral Diseases, Beijing Key Laboratory of Digital Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081, PR China
| | - Yunsong Liu
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, National Clinical Research Center for Oral Diseases, Beijing Key Laboratory of Digital Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081, PR China
| | - Longwei Lv
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, National Clinical Research Center for Oral Diseases, Beijing Key Laboratory of Digital Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081, PR China.
| | - Yongsheng Zhou
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, National Clinical Research Center for Oral Diseases, Beijing Key Laboratory of Digital Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081, PR China.
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61
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Jain D, Mattiassi S, Goh EL, Yim EKF. Extracellular matrix and biomimetic engineering microenvironment for neuronal differentiation. Neural Regen Res 2020; 15:573-585. [PMID: 31638079 PMCID: PMC6975142 DOI: 10.4103/1673-5374.266907] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Extracellular matrix (ECM) influences cell differentiation through its structural and biochemical properties. In nervous system, neuronal behavior is influenced by these ECMs structures which are present in a meshwork, fibrous, or tubular forms encompassing specific molecular compositions. In addition to contact guidance, ECM composition and structures also exert its effect on neuronal differentiation. This short report reviewed the native ECM structure and composition in central nervous system and peripheral nervous system, and their impact on neural regeneration and neuronal differentiation. Using topographies, stem cells have been differentiated to neurons. Further, focussing on engineered biomimicking topographies, we highlighted the role of anisotropic topographies in stem cell differentiation to neurons and its recent temporal application for efficient neuronal differentiation.
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Affiliation(s)
- Deepak Jain
- Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Sabrina Mattiassi
- Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Eyleen L Goh
- Neuroscience Academic Clinical Programme, Duke-NUS Medical School, Singapore
| | - Evelyn K F Yim
- Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario, Canada
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Makhija EP, Espinosa-Hoyos D, Jagielska A, Van Vliet KJ. Mechanical regulation of oligodendrocyte biology. Neurosci Lett 2019; 717:134673. [PMID: 31838017 DOI: 10.1016/j.neulet.2019.134673] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 11/25/2019] [Accepted: 12/01/2019] [Indexed: 12/27/2022]
Abstract
Oligodendrocytes (OL) are a subset of glial cells in the central nervous system (CNS) comprising the brain and spinal cord. The CNS environment is defined by complex biochemical and biophysical cues during development and response to injury or disease. In the last decade, significant progress has been made in understanding some of the key biophysical factors in the CNS that modulate OL biology, including their key role in myelination of neurons. Taken together, those studies offer translational implications for remyelination therapies, pharmacological research, identification of novel drug targets, and improvements in methods to generate human oligodendrocyte progenitor cells (OPCs) and OLs from donor stem cells in vitro. This review summarizes current knowledge of how various physical and mechanical cues affect OL biology and its implications for disease, therapeutic approaches, and generation of human OPCs and OLs.
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Affiliation(s)
- Ekta P Makhija
- BioSystems & Micromechanics (BioSyM) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, Singapore 138602; Critical Analytics for Manufacturing Personalized-Medicine (CAMP) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, 138602, Singapore
| | - Daniela Espinosa-Hoyos
- BioSystems & Micromechanics (BioSyM) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, Singapore 138602; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Anna Jagielska
- BioSystems & Micromechanics (BioSyM) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, Singapore 138602; Department of Materials Science & Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA.
| | - Krystyn J Van Vliet
- BioSystems & Micromechanics (BioSyM) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, Singapore 138602; Critical Analytics for Manufacturing Personalized-Medicine (CAMP) Interdisciplinary Research Group, Singapore-MIT Alliance for Research & Technology (SMART) CREATE, 138602, Singapore; Department of Materials Science & Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA.
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63
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Groden M, Weigand M, Triesch J, Jedlicka P, Cuntz H. A Model of Brain Folding Based on Strong Local and Weak Long-Range Connectivity Requirements. Cereb Cortex 2019; 30:2434-2451. [DOI: 10.1093/cercor/bhz249] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 08/20/2019] [Accepted: 10/01/2019] [Indexed: 12/21/2022] Open
Abstract
Abstract
Throughout the animal kingdom, the structure of the central nervous system varies widely from distributed ganglia in worms to compact brains with varying degrees of folding in mammals. The differences in structure may indicate a fundamentally different circuit organization. However, the folded brain most likely is a direct result of mechanical forces when considering that a larger surface area of cortex packs into the restricted volume provided by the skull. Here, we introduce a computational model that instead of modeling mechanical forces relies on dimension reduction methods to place neurons according to specific connectivity requirements. For a simplified connectivity with strong local and weak long-range connections, our model predicts a transition from separate ganglia through smooth brain structures to heavily folded brains as the number of cortical columns increases. The model reproduces experimentally determined relationships between metrics of cortical folding and its pathological phenotypes in lissencephaly, polymicrogyria, microcephaly, autism, and schizophrenia. This suggests that mechanical forces that are known to lead to cortical folding may synergistically contribute to arrangements that reduce wiring. Our model provides a unified conceptual understanding of gyrification linking cellular connectivity and macroscopic structures in large-scale neural network models of the brain.
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Affiliation(s)
- Moritz Groden
- Ernst Strüngmann Institute (ESI) for Neuroscience in Cooperation with Max Planck Society, Frankfurt am Main D-60528, Germany
- Frankfurt Institute for Advanced Studies (FIAS), Frankfurt am Main D-60438, Germany
- ICAR3R—Interdisciplinary Centre for 3Rs in Animal Research, Justus Liebig University Giessen, Giessen D-35390, Germany
| | - Marvin Weigand
- Ernst Strüngmann Institute (ESI) for Neuroscience in Cooperation with Max Planck Society, Frankfurt am Main D-60528, Germany
- Frankfurt Institute for Advanced Studies (FIAS), Frankfurt am Main D-60438, Germany
- Faculty of Biological Sciences, Goethe University, Frankfurt am Main D-60438, Germany
| | - Jochen Triesch
- Frankfurt Institute for Advanced Studies (FIAS), Frankfurt am Main D-60438, Germany
- Faculty of Physics, Goethe University, Frankfurt am Main D-60438, Germany
- Faculty of Computer Science and Mathematics, Goethe University, Frankfurt am Main D-60438, Germany
| | - Peter Jedlicka
- Frankfurt Institute for Advanced Studies (FIAS), Frankfurt am Main D-60438, Germany
- ICAR3R—Interdisciplinary Centre for 3Rs in Animal Research, Justus Liebig University Giessen, Giessen D-35390, Germany
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe University, Frankfurt am Main D-60528, Germany
| | - Hermann Cuntz
- Ernst Strüngmann Institute (ESI) for Neuroscience in Cooperation with Max Planck Society, Frankfurt am Main D-60528, Germany
- Frankfurt Institute for Advanced Studies (FIAS), Frankfurt am Main D-60438, Germany
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64
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Heuer K, Toro R. Role of mechanical morphogenesis in the development and evolution of the neocortex. Phys Life Rev 2019; 31:233-239. [DOI: 10.1016/j.plrev.2019.01.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 12/20/2018] [Accepted: 01/15/2019] [Indexed: 01/05/2023]
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Nichol RH, Catlett TS, Onesto MM, Hollender D, Gómez TM. Environmental Elasticity Regulates Cell-type Specific RHOA Signaling and Neuritogenesis of Human Neurons. Stem Cell Reports 2019; 13:1006-1021. [PMID: 31708476 PMCID: PMC6915847 DOI: 10.1016/j.stemcr.2019.10.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 02/08/2023] Open
Abstract
The microenvironment of developing neurons is a dynamic landscape of both chemical and mechanical cues that regulate cell proliferation, differentiation, migration, and axon extension. While the regulatory roles of chemical ligands in neuronal morphogenesis have been described, little is known about how mechanical forces influence neurite development. Here, we tested how substratum elasticity regulates neurite development of human forebrain (hFB) neurons and human motor neurons (hMNs), two populations of neurons that naturally extend axons into distinct elastic environments. Using polyacrylamide and collagen hydrogels of varying compliance, we find that hMNs preferred rigid conditions that approximate the elasticity of muscle, whereas hFB neurons preferred softer conditions that approximate brain tissue elasticity. More stable leading-edge protrusions, increased peripheral adhesions, and elevated RHOA signaling of hMN growth cones contributed to faster neurite outgrowth on rigid substrata. Our data suggest that RHOA balances contractile and adhesive forces in response to substratum elasticity. Motor neurons derived from hiPSCs are tuned to grow optimally on rigid substrata hiPSCs derived forebrain neurons prefer softer substrata RHOA-dependent adhesion contributes to elasticity preferences Modulating RHOA affects axon development depending on substrata elasticity
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Affiliation(s)
- Robert H Nichol
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA; Neuroscience Training Program, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA
| | - Timothy S Catlett
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA; Graduate Program in Cellular and Molecular Biology, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA
| | - Massimo M Onesto
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA
| | - Drew Hollender
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA
| | - Timothy M Gómez
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA; Neuroscience Training Program, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA; Graduate Program in Cellular and Molecular Biology, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA.
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Saito K, Okamoto M, Watanabe Y, Noguchi N, Nagasaka A, Nishina Y, Shinoda T, Sakakibara A, Miyata T. Dorsal-to-Ventral Cortical Expansion Is Physically Primed by Ventral Streaming of Early Embryonic Preplate Neurons. Cell Rep 2019; 29:1555-1567.e5. [DOI: 10.1016/j.celrep.2019.09.075] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/11/2019] [Accepted: 09/25/2019] [Indexed: 01/08/2023] Open
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Tatic N, Rose FRAJ, des Rieux A, White LJ. Stem cells from the dental apical papilla in extracellular matrix hydrogels mitigate inflammation of microglial cells. Sci Rep 2019; 9:14015. [PMID: 31570730 PMCID: PMC6768850 DOI: 10.1038/s41598-019-50367-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 09/06/2019] [Indexed: 12/15/2022] Open
Abstract
After spinal cord injury (SCI) chronic inflammation hampers regeneration. Influencing the local microenvironment after SCI may provide a strategy to modulate inflammation and the immune response. The objectives of this work were to determine whether bone or spinal cord derived ECM hydrogels can deliver human mesenchymal stem cells from the apical papilla (SCAP) to reduce local inflammation and provide a regenerative microenvironment. Bone hydrogels (8 and 10 mg/ml, B8 and B10) and spinal cord hydrogels (8 mg/ml, S8) supplemented with fibrin possessed a gelation rate and a storage modulus compatible with spinal cord implantation. S8 and B8 impact on the expression of anti and pro-inflammatory cytokines (Arg1, Nos2, Tnf) in LPS treated microglial cells were assessed using solubilised and solid hydrogel forms. S8 significantly reduced the Nos2/Arg1 ratio and solubilised B8 significantly reduced Tnf and increased Arg1 whereas solid S8 and B8 did not impact inflammation in microglial cells. SCAP incorporation within ECM hydrogels did not impact upon SCAP immunoregulatory properties, with significant downregulation of Nos2/Arg1 ratio observed for all SCAP embedded hydrogels. Tnf expression was reduced with SCAP embedded in B8, reflecting the gene expression observed with the innate hydrogel. Thus, ECM hydrogels are suitable vehicles to deliver SCAP due to their physical properties, preservation of SCAP viability and immunomodulatory capacity.
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Affiliation(s)
- Natalija Tatic
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom
- Université catholique de Louvain, Louvain Drug Research Institute, Advanced Drug Delivery and Biomaterials, Brussels, 1200, Belgium
| | - Felicity R A J Rose
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Anne des Rieux
- Université catholique de Louvain, Louvain Drug Research Institute, Advanced Drug Delivery and Biomaterials, Brussels, 1200, Belgium
| | - Lisa J White
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom.
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68
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Suar ZM, Fabris G, Kurt M. Isolation and Immunofluorescent Staining of Fresh Rat Pia-Arachnoid Complex Tissue for Micromechanical Characterization. ACTA ACUST UNITED AC 2019; 89:e83. [PMID: 31532920 DOI: 10.1002/cpns.83] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In this article, we describe a protocol for the isolation and staining of fresh tissue of the inner rat meningeal layers, or pia-arachnoid complex (PAC). The PAC is believed to act as a mechanical damper offering a fundamental layer of protection against brain injury; however, its overall mechanical properties are still rather unexplored. In order to perform micromechanical measurements on the PAC, the tissue must be extracted and characterized while maintaining its native mechanical properties (i.e., avoiding any chemical or physical modification that could alter it). In light of this need, we developed a protocol for the immunofluorescent staining of fresh PAC tissue that does not require any fixation or permeabilization step. This approach will allow researchers to investigate important properties of the anatomy of ex vivo PAC tissue while at the same time offering a platform for the mechanical analysis of this complex material. © 2019 by John Wiley & Sons, Inc. Basic Protocol 1: Isolation of fresh rat pia-arachnoid complex tissue Basic Protocol 2: Fresh immunofluorescent staining of rat pia-arachnoid complex tissue Alternate Protocol: Adhesion of pia-arachnoid complex tissue to glass slides for micromechanical characterization.
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Affiliation(s)
- Zeynep M Suar
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, New Jersey
| | - Gloria Fabris
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, New Jersey
| | - Mehmet Kurt
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, New Jersey.,Translational and Molecular Imaging Institute (TMII), Mount Sinai Hospital, New York, New York
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69
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Mahajan G, Lee MY, Kothapalli C. Biophysical and biomechanical properties of neural progenitor cells as indicators of developmental neurotoxicity. Arch Toxicol 2019; 93:2979-2992. [PMID: 31428840 DOI: 10.1007/s00204-019-02549-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Accepted: 08/14/2019] [Indexed: 11/24/2022]
Abstract
Conventional in vitro toxicity studies have focused on identifying IC50 and the underlying mechanisms, but how toxicants influence biophysical and biomechanical changes in human cells, especially during developmental stages, remain understudied. Here, using an atomic force microscope, we characterized changes in biophysical (cell area, actin organization) and biomechanical (Young's modulus, force of adhesion, tether force, membrane tension, tether radius) aspects of human fetal brain-derived neural progenitor cells (NPCs) induced by four classes of widely used toxic compounds, including rotenone, digoxin, N-arachidonoylethanolamide (AEA), and chlorpyrifos, under exposure up to 36 h. The sub-cellular mechanisms (apoptosis, mitochondria membrane potential, DNA damage, glutathione levels) by which these toxicants induced biochemical changes in NPCs were assessed. Results suggest a significant compromise in cell viability with increasing toxicant concentration (p < 0.01), and biophysical and biomechanical characteristics with increasing exposure time (p < 0.01) as well as toxicant concentration (p < 0.01). Impairment of mitochondrial membrane potential appears to be the most sensitive mechanism of neurotoxicity for rotenone, AEA and chlorpyrifos exposure, but compromise in plasma membrane integrity for digoxin exposure. The surviving NPCs remarkably retained stemness (SOX2 expression) even at high toxicant concentrations. A negative linear correlation (R2 = 0.92) exists between the elastic modulus of surviving cells and the number of living cells in that environment. We propose that even subtle compromise in cell mechanics could serve as a crucial marker of developmental neurotoxicity (mechanotoxicology) and therefore should be included as part of toxicology assessment repertoire to characterize as well as predict developmental outcomes.
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Affiliation(s)
- Gautam Mahajan
- Department of Chemical and Biomedical Engineering, Washkewicz College of Engineering, Cleveland State University, 2121 Euclid Ave, FH 460, Cleveland, OH, 44115, USA
| | - Moo-Yeal Lee
- Department of Chemical and Biomedical Engineering, Washkewicz College of Engineering, Cleveland State University, 2121 Euclid Ave, FH 460, Cleveland, OH, 44115, USA
| | - Chandrasekhar Kothapalli
- Department of Chemical and Biomedical Engineering, Washkewicz College of Engineering, Cleveland State University, 2121 Euclid Ave, FH 460, Cleveland, OH, 44115, USA.
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70
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Krukiewicz K, Fernandez J, Skorupa M, Więcławska D, Poudel A, Sarasua JR, Quinlan LR, Biggs MJP. Analysis of a poly(ε-decalactone)/silver nanowire composite as an electrically conducting neural interface biomaterial. BMC Biomed Eng 2019; 1:9. [PMID: 32903306 PMCID: PMC7422568 DOI: 10.1186/s42490-019-0010-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 03/22/2019] [Indexed: 11/10/2022] Open
Abstract
Background Advancement in polymer technologies, facilitated predominantly through chemical engineering approaches or through the identification and utilization of novel renewable resources, has been a steady focus of biomaterials research for the past 50 years. Aliphatic polyesters have been exploited in numerous biomedical applications including the formulation of soft-tissue sutures, bone fixation devices, cardiovascular stents etc. Biomimetic ‘soft’ polymer formulations are of interest in the design of biological interfaces and specifically, in the development of implantable neuroelectrode systems intended to interface with neural tissues. Critically, soft polymer formulations have been shown to address the challenges associated with the disregulation of mechanotransductive processes and micro-motion induced inflammation at the electrode/tissue interface. In this study, a polyester-based poly(ε-decalactone)/silver nanowire (EDL:Ag) composite was investigated as a novel electrically active biomaterial with neural applications. Neural interfaces were formulated through spin coating of a polymer/nanowire formulation onto the surface of a Pt electrode to form a biocompatible EDL matrix supported by a percolated network of silver nanowires. As-formed EDL:Ag composites were characterized by means of infrared spectroscopy, scanning electron microscopy and electrochemical methods, with their cytocompatibility assessed using primary cultures of a mixed neural population obtained from the ventral mesencephalon of Sprague-Dawley rat embryos. Results Electrochemical characterization of various EDL:Ag composites indicated EDL:Ag 10:1 as the most favourable formulation, exhibiting high charge storage capacity (8.7 ± 1.0 mC/cm2), charge injection capacity (84.3 ± 1.4 μC/cm2) and low impedance at 1 kHz (194 ± 28 Ω), outperforming both pristine EDL and bare Pt electrodes. The in vitro biological evaluation showed that EDL:Ag supported significant neuron viability in culture and to promote neurite outgrowth, which had the average length of 2300 ± 6 μm following 14 days in culture, 60% longer than pristine EDL and 120% longer than bare Pt control substrates. Conclusions EDL:Ag nanocomposites are shown to serve as robust neural interface materials, possessing favourable electrochemical characteristics together with high neural cytocompatibility.
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Affiliation(s)
- Katarzyna Krukiewicz
- Centre for Research in Medical Devices (CURAM), Galway Biosciences Research Building, 118 Corrib Village, Newcastle, Galway, Ireland.,Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, M.Strzody 9, 44-100 Gliwice, Poland
| | - Jorge Fernandez
- Polimerbio, S.L, Paseo Mikeletegi 83, 20009 Donostia-San Sebastian, Spain
| | - Małgorzata Skorupa
- Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, M.Strzody 9, 44-100 Gliwice, Poland
| | - Daria Więcławska
- Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, M.Strzody 9, 44-100 Gliwice, Poland
| | - Anup Poudel
- Centre for Research in Medical Devices (CURAM), Galway Biosciences Research Building, 118 Corrib Village, Newcastle, Galway, Ireland
| | - Jose-Ramon Sarasua
- Department of Mining-Metallurgy Engineering and Materials Science, POLYMAT, University of the Basque Country (UPV/EHU), School of Engineering, Alameda de Urquijo s/n, 48013 Bilbao, Spain
| | - Leo R Quinlan
- Department of Physiology, National University of Ireland, Galway, University Road, Galway, Ireland
| | - Manus J P Biggs
- Centre for Research in Medical Devices (CURAM), Galway Biosciences Research Building, 118 Corrib Village, Newcastle, Galway, Ireland
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O'Donnell JC, Browne KD, Kilbaugh TJ, Chen HI, Whyte J, Cullen DK. Challenges and demand for modeling disorders of consciousness following traumatic brain injury. Neurosci Biobehav Rev 2019; 98:336-346. [PMID: 30550859 PMCID: PMC7847278 DOI: 10.1016/j.neubiorev.2018.12.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 11/02/2018] [Accepted: 12/11/2018] [Indexed: 12/29/2022]
Abstract
Following severe traumatic brain injury (TBI), many patients experience coma - an unresponsive state lacking wakefulness or awareness. Coma rarely lasts more than two weeks, and emergence involves passing through a state of wakefulness without awareness of self or environment. Patients that linger in these Disorders of Consciousness (DoC) undergo clinical assessments of awareness for diagnosis into Unresponsive Wakefulness Syndrome (no awareness, also called vegetative state) or Minimally Conscious State (periodic increases in awareness). These diagnoses are notoriously inaccurate, offering little prognostic value. Recovery of awareness is unpredictable, returning within weeks, years, or never. This leaves patients' families with difficult decisions and little information on which to base them. Clinical studies have made significant advancements, but remain encumbered by high variability, limited data output, and a lack of necessary controls. Herein we discuss the clear and present need to establish a preclinical model of TBI-induced DoC, the significant challenges involved, and how such a model can be applied to support DoC research.
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Affiliation(s)
- John C O'Donnell
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - Kevin D Browne
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - Todd J Kilbaugh
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine, University of Pennsylvania, The Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - H Isaac Chen
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - John Whyte
- Moss Rehabilitation Research Institute, Elkins Park, PA, United States
| | - D Kacy Cullen
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States; Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States.
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72
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Gong Z, Fang C, You R, Shao X, Wei X, Chang RCC, Lin Y. Distinct relaxation timescales of neurites revealed by rate-dependent indentation, relaxation and micro-rheology tests. SOFT MATTER 2019; 15:166-174. [PMID: 30420982 DOI: 10.1039/c8sm01747f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Although the dynamic response of neurites is believed to play crucial roles in processes like axon outgrowth and formation of the neural network, the dynamic mechanical properties of such protrusions remain poorly understood. In this study, by using AFM (atomic force microscopy) indentation, we systematically examined the dynamic behavior of well-developed neurites on primary neurons under different loading modes (step loading, oscillating loading and ramp loading). Interestingly, the response was found to be strongly rate-dependent, with an apparent initial and long-term elastic modulus around 800 and 80 Pa, respectively. To better analyze the measurement data and extract information of key interest, the finite element simulation method (FEM) was also conducted where the neurite was treated as a viscoelastic solid consisting of multiple characteristic relaxation times. It was found that a minimum of three relaxation timescales, i.e. ∼0.01, 0.1 and 1 seconds, are needed to explain the observed relaxation curve as well as fit simulation results to the indentation and rheology data under different loading rates and driving frequencies. We further demonstrated that these three characteristic relaxation times likely originate from the thermal fluctuations of the microtubule, membrane relaxation and cytosol viscosity, respectively. By identifying key parameters describing the time-dependent behavior of neurites, as well as revealing possible physical mechanisms behind, this study could greatly help us understand how neural cells perform their biological duties over a wide spectrum of timescales.
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Affiliation(s)
- Ze Gong
- Department of Mechanical Engineering, University of Hong Kong, Hong Kong SAR, China.
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73
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Fouquet C, Trembleau A. Preparation and Manipulation of Olfactory Epithelium Explant Cultures for Measurement of the Mechanical Tension of Individual Axons Using the Biomembrane Force Probe. Bio Protoc 2019; 9:e3213. [PMID: 31131294 DOI: 10.21769/bioprotoc.3213] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In this paper, we describe a protocol allowing measurement of the mechanical tension of individual axons grown ex vivo from neural tissue explants. This protocol was developed with primary cultures of olfactory epithelium explants from embryonic (E13.5) mice. It includes a detailed description of explant dissection and culture, as well as the main steps of the procedure for axon tension measurement using the previously established Biomembrane Force Probe.
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Affiliation(s)
- Coralie Fouquet
- Sorbonne Université, CNRS, INSERM, Institut de Biologie Paris Seine, Laboratoire Neuroscience Paris Seine, F-75005 Paris, France
| | - Alain Trembleau
- Sorbonne Université, CNRS, INSERM, Institut de Biologie Paris Seine, Laboratoire Neuroscience Paris Seine, F-75005 Paris, France
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Tropomyosin Tpm 2.1 loss induces glioblastoma spreading in soft brain-like environments. J Neurooncol 2018; 141:303-313. [PMID: 30535593 DOI: 10.1007/s11060-018-03049-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 11/12/2018] [Indexed: 12/25/2022]
Abstract
INTRODUCTION The brain is a very soft tissue. Glioblastoma (GBM) brain tumours are highly infiltrative into the surrounding healthy brain tissue and invasion mechanisms that have been defined using rigid substrates therefore may not apply to GBM dissemination. GBMs characteristically lose expression of the high molecular weight tropomyosins, a class of actin-associating proteins and essential regulators of the actin stress fibres and focal adhesions that underpin cell migration on rigid substrates. METHODS Here, we investigated how loss of the high molecular weight tropomyosins affects GBM on soft matrices that recapitulate the biomechanical architecture of the brain. RESULTS We find that Tpm 2.1 is down-regulated in GBM grown on soft substrates. We demonstrate that Tpm 2.1 depletion by siRNA induces cell spreading and elongation in soft 3D hydrogels, irrespective of matrix composition. Tpm 1.7, a second high molecular weight tropomyosin is also down-regulated when cells are cultured on soft brain-like surfaces and we show that effects of this isoform are matrix dependent, with Tpm 1.7 inducing cell rounding in 3D collagen gels. Finally, we show that the absence of Tpm 2.1 from primary patient-derived GBMs correlates with elongated, mesenchymal invasion. CONCLUSIONS We propose that Tpm 2.1 down-regulation facilitates GBM colonisation of the soft brain environment. This specialisation of the GBM actin cytoskeleton organisation that is highly suited to the soft brain-like environment may provide novel therapeutic targets for arresting GBM invasion.
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75
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Kilinc D. The Emerging Role of Mechanics in Synapse Formation and Plasticity. Front Cell Neurosci 2018; 12:483. [PMID: 30574071 PMCID: PMC6291423 DOI: 10.3389/fncel.2018.00483] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 11/27/2018] [Indexed: 12/26/2022] Open
Abstract
The regulation of synaptic strength forms the basis of learning and memory, and is a key factor in understanding neuropathological processes that lead to cognitive decline and dementia. While the mechanical aspects of neuronal development, particularly during axon growth and guidance, have been extensively studied, relatively little is known about the mechanical aspects of synapse formation and plasticity. It is established that a filamentous actin network with complex spatiotemporal behavior controls the dendritic spine shape and size, which is thought to be crucial for activity-dependent synapse plasticity. Accordingly, a number of actin binding proteins have been identified as regulators of synapse plasticity. On the other hand, a number of cell adhesion molecules (CAMs) are found in synapses, some of which form transsynaptic bonds to align the presynaptic active zone (PAZ) with the postsynaptic density (PSD). Considering that these CAMs are key components of cellular mechanotransduction, two critical questions emerge: (i) are synapses mechanically regulated? and (ii) does disrupting the transsynaptic force balance lead to (or exacerbate) synaptic failure? In this mini review article, I will highlight the mechanical aspects of synaptic structures-focusing mainly on cytoskeletal dynamics and CAMs-and discuss potential mechanoregulation of synapses and its relevance to neurodegenerative diseases.
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Affiliation(s)
- Devrim Kilinc
- INSERM U1167, Institut Pasteur de Lille, Lille, France
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76
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Razetti A, Medioni C, Malandain G, Besse F, Descombes X. A stochastic framework to model axon interactions within growing neuronal populations. PLoS Comput Biol 2018; 14:e1006627. [PMID: 30507939 PMCID: PMC6292646 DOI: 10.1371/journal.pcbi.1006627] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 12/13/2018] [Accepted: 11/09/2018] [Indexed: 12/16/2022] Open
Abstract
The confined and crowded environment of developing brains imposes spatial constraints on neuronal cells that have evolved individual and collective strategies to optimize their growth. These include organizing neurons into populations extending their axons to common target territories. How individual axons interact with each other within such populations to optimize innervation is currently unclear and difficult to analyze experimentally in vivo. Here, we developed a stochastic model of 3D axon growth that takes into account spatial environmental constraints, physical interactions between neighboring axons, and branch formation. This general, predictive and robust model, when fed with parameters estimated on real neurons from the Drosophila brain, enabled the study of the mechanistic principles underlying the growth of axonal populations. First, it provided a novel explanation for the diversity of growth and branching patterns observed in vivo within populations of genetically identical neurons. Second, it uncovered that axon branching could be a strategy optimizing the overall growth of axons competing with others in contexts of high axonal density. The flexibility of this framework will make it possible to investigate the rules underlying axon growth and regeneration in the context of various neuronal populations. Understanding how neuronal cells establish complex circuits with specific functions within a developing brain is a major current challenge. Over the last past years, enormous progress has been done to precisely resolve brain anatomy and to dissect the mechanisms controlling the establishment of precise neuronal networks. However, due to the extreme complexity of the brain, it is still experimentally difficult to investigate in vivo how neurons interact with each other and with their physical environments to innervate target territories during development. Here, we have developed a framework that integrates a dynamic 3D mathematical model of single axonal growth with parameters estimated from neurons grown in vivo and simulations of entire populations of growing axons. The emergent properties of our model enable the study of the mechanistic principles underlying the growth of axonal population in developing brains. Specifically, our results highlight the impact of mechanical interactions on both individual and collective axon growth, and uncover how branching regulate this process.
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77
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Goodhill GJ. Theoretical Models of Neural Development. iScience 2018; 8:183-199. [PMID: 30321813 PMCID: PMC6197653 DOI: 10.1016/j.isci.2018.09.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 08/06/2018] [Accepted: 09/19/2018] [Indexed: 12/22/2022] Open
Abstract
Constructing a functioning nervous system requires the precise orchestration of a vast array of mechanical, molecular, and neural-activity-dependent cues. Theoretical models can play a vital role in helping to frame quantitative issues, reveal mathematical commonalities between apparently diverse systems, identify what is and what is not possible in principle, and test the abilities of specific mechanisms to explain the data. This review focuses on the progress that has been made over the last decade in our theoretical understanding of neural development.
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Affiliation(s)
- Geoffrey J Goodhill
- Queensland Brain Institute and School of Mathematics and Physics, The University of Queensland, St Lucia, QLD 4072, Australia.
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78
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Mair DB, Ames HM, Li R. Mechanisms of invasion and motility of high-grade gliomas in the brain. Mol Biol Cell 2018; 29:2509-2515. [PMID: 30325290 PMCID: PMC6254577 DOI: 10.1091/mbc.e18-02-0123] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 06/04/2018] [Accepted: 08/10/2018] [Indexed: 11/30/2022] Open
Abstract
High-grade gliomas are especially difficult tumors to treat due to their invasive behavior. This has led to extensive research focusing on arresting glioma cell migration. Cell migration involves the sensing of a migratory cue, followed by polarization in the direction of the cue, and reorganization of the actin cytoskeleton to allow for a protrusive leading edge and a contractile trailing edge. Transmission of these forces to produce motility also requires adhesive interactions of the cell with the extracellular microenvironment. In glioma cells, transmembrane receptors such as CD44 and integrins bind the cell to the surrounding extracellular matrix that provides a substrate on which the cell can exert the requisite forces for cell motility. These various essential parts of the migratory machinery are potential targets to halt glioma cell invasion. In this review, we discuss the mechanisms of glioma cell migration and how they may be targeted in anti-invasion therapies.
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Affiliation(s)
- Devin B. Mair
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Heather M. Ames
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Rong Li
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218
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79
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Garcia KE, Kroenke CD, Bayly PV. Mechanics of cortical folding: stress, growth and stability. Philos Trans R Soc Lond B Biol Sci 2018; 373:rstb.2017.0321. [PMID: 30249772 DOI: 10.1098/rstb.2017.0321] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/28/2018] [Indexed: 12/17/2022] Open
Abstract
Cortical folding, or gyrification, coincides with several important developmental processes. The folded shape of the human brain allows the cerebral cortex, the thin outer layer of neurons and their associated projections, to attain a large surface area relative to brain volume. Abnormal cortical folding has been associated with severe neurological, cognitive and behavioural disorders, such as epilepsy, autism and schizophrenia. However, despite decades of study, the mechanical forces that lead to cortical folding remain incompletely understood. Leading hypotheses have focused on the roles of (i) tangential growth of the outer cortex, (ii) spatio-temporal patterns in the birth and migration of neurons, and (iii) internal tension in axons. Recent experimental studies have illuminated not only the fundamental cellular and molecular processes underlying cortical development, but also the stress state, mechanical properties and spatio-temporal patterns of growth in the developing brain. The combination of mathematical modelling and physical measurements has allowed researchers to evaluate hypothesized mechanisms of folding, to determine whether each is consistent with physical laws. This review summarizes what physical scientists have learned from models and recent experimental observations, in the context of recent neurobiological discoveries regarding cortical development. Here, we highlight evidence of a combined mechanism, in which spatio-temporal patterns bias the locations of primary folds (i), but tangential growth of the cortical plate induces mechanical instability (ii) to propagate primary and higher-order folds.This article is part of the Theo Murphy meeting issue 'Mechanics of development'.
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Affiliation(s)
- K E Garcia
- Mechanical Engineering and Materials Science, Washington University in Saint Louis, Saint Louis, MO, USA.,Engineering, University of Southern Indiana, Evansville, IN, USA
| | - C D Kroenke
- Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, USA
| | - P V Bayly
- Mechanical Engineering and Materials Science, Washington University in Saint Louis, Saint Louis, MO, USA
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80
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Regional variations in stiffness in live mouse brain tissue determined by depth-controlled indentation mapping. Sci Rep 2018; 8:12517. [PMID: 30131608 PMCID: PMC6104037 DOI: 10.1038/s41598-018-31035-y] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 08/10/2018] [Indexed: 11/08/2022] Open
Abstract
The mechanical properties of brain tissue play a pivotal role in neurodevelopment and neurological disorders. Yet, at present, there is no consensus on how the different structural parts of the tissue contribute to its stiffness variations. Here, we have gathered depth-controlled indentation viscoelasticity maps of the hippocampus of acute horizontal live mouse brain slices. Our results confirm the highly viscoelestic nature of brain tissue. We further show that the mechanical properties are non-uniform and at least related to differences in morphological composition. Interestingly, areas with higher nuclear density appear to be softer than areas with lower nuclear density.
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81
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Culture of human neurospheres in 3D scaffolds for developmental neurotoxicity testing. Toxicol In Vitro 2018; 52:106-115. [PMID: 29883730 DOI: 10.1016/j.tiv.2018.06.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 05/28/2018] [Accepted: 06/01/2018] [Indexed: 11/24/2022]
Abstract
Human neural progenitor cells cultured as neurospheres are a promising tool for developmental neurotoxicity testing in vitro. In order to obtain a human cell-based tissue culture system as close to the organ as possible, it is desirable to improve the spatial organization of the "Neurosphere Assay" and use 3D scaffolds to better mimic the in vivo three dimensional cell microenvironment. For this reason we have established the conditions for short-term culture (up to 6 days) in matrigel or in IKVAV-3 peptide-functionalized hydrogels, and for long-term culture (>25 days) in IKVAV-3 peptide-functionalized hydrogels showing that these conditions support human neural progenitor cells' migration, differentiation to neurons and formation of neuronal networks. Moreover, we assessed if neurospheres grown in 3D scaffolds allow for developmental neurotoxicity compound testing. At concentrations not affecting cell viability the known developmental neurotoxic compound MeHgCl inhibits migration of human neural progenitor cells grown in 3D scaffolds with a higher potency than when the same cells are cultured on a laminin-coated surface as secondary 3D structures. Thus, this work opens the door to functional assessment of compound effects on short- and long-term cultured human neurospheres embedded in 3D scaffolds for developmental neurotoxicity testing.
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82
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Gahl TJ, Kunze A. Force-Mediating Magnetic Nanoparticles to Engineer Neuronal Cell Function. Front Neurosci 2018; 12:299. [PMID: 29867315 PMCID: PMC5962660 DOI: 10.3389/fnins.2018.00299] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 04/18/2018] [Indexed: 12/12/2022] Open
Abstract
Cellular processes like membrane deformation, cell migration, and transport of organelles are sensitive to mechanical forces. Technically, these cellular processes can be manipulated through operating forces at a spatial precision in the range of nanometers up to a few micrometers through chaperoning force-mediating nanoparticles in electrical, magnetic, or optical field gradients. But which force-mediating tool is more suitable to manipulate cell migration, and which, to manipulate cell signaling? We review here the differences in forces sensation to control and engineer cellular processes inside and outside the cell, with a special focus on neuronal cells. In addition, we discuss technical details and limitations of different force-mediating approaches and highlight recent advancements of nanomagnetics in cell organization, communication, signaling, and intracellular trafficking. Finally, we give suggestions about how force-mediating nanoparticles can be used to our advantage in next-generation neurotherapeutic devices.
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Affiliation(s)
| | - Anja Kunze
- Department of Electrical and Computer Engineering, Montana State University, Bozeman, MT, United States
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83
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Gangatharan G, Schneider-Maunoury S, Breau MA. Role of mechanical cues in shaping neuronal morphology and connectivity. Biol Cell 2018; 110:125-136. [PMID: 29698566 DOI: 10.1111/boc.201800003] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 04/09/2018] [Indexed: 02/06/2023]
Abstract
Neuronal circuits, the functional building blocks of the nervous system, assemble during development through a series of dynamic processes including the migration of neurons to their final position, the growth and navigation of axons and their synaptic connection with target cells. While the role of chemical cues in guiding neuronal migration and axonal development has been extensively analysed, the contribution of mechanical inputs, such as forces and stiffness, has received far less attention. In this article, we review the in vitro and more recent in vivo studies supporting the notion that mechanical signals are critical for multiple aspects of neuronal circuit assembly, from the emergence of axons to the formation of functional synapses. By combining live imaging approaches with tools designed to measure and manipulate the mechanical environment of neurons, the emerging field of neuromechanics will add a new paradigm in our understanding of neuronal development and potentially inspire novel regenerative therapies.
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Affiliation(s)
- Girisaran Gangatharan
- Sorbonne Université, CNRS UMR 7622, Laboratoire de Biologie du Développement-Institut de Biologie Paris Seine (LBD-IBPS), INSERM, Paris, 75005, France
| | - Sylvie Schneider-Maunoury
- Sorbonne Université, CNRS UMR 7622, Laboratoire de Biologie du Développement-Institut de Biologie Paris Seine (LBD-IBPS), INSERM, Paris, 75005, France
| | - Marie Anne Breau
- Sorbonne Université, CNRS UMR 7622, Laboratoire de Biologie du Développement-Institut de Biologie Paris Seine (LBD-IBPS), INSERM, Paris, 75005, France.,Sorbonne Université, CNRS UMR 8237, Laboratoire Jean Perrin, Paris, 75005, France
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84
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Tanner K. Perspective: The role of mechanobiology in the etiology of brain metastasis. APL Bioeng 2018; 2:031801. [PMID: 31069312 PMCID: PMC6324204 DOI: 10.1063/1.5024394] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/18/2018] [Indexed: 12/11/2022] Open
Abstract
Tumor latency and dormancy are obstacles to effective cancer treatment. In brain
metastases, emergence of a lesion can occur at varying intervals from diagnosis
and in some cases following successful treatment of the primary tumor. Genetic
factors that drive brain metastases have been identified, such as those involved
in cell adhesion, signaling, extravasation, and metabolism. From this wealth of
knowledge, vexing questions still remain; why is there a difference in strategy
to facilitate outgrowth and why is there a difference in latency? One missing
link may be the role of tissue biophysics of the brain microenvironment in
infiltrating cells. Here, I discuss the mechanical cues that may influence
disseminated tumor cells in the brain, as a function of age and disease. I
further discuss in vitro and in vivo
preclinical models such as 3D culture systems and zebrafish to study the role of
the mechanical environment in brain metastasis in an effort of providing novel
targeted therapeutics.
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Affiliation(s)
- Kandice Tanner
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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85
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Local traction force in the proximal leading process triggers nuclear translocation during neuronal migration. Neurosci Res 2018; 142:38-48. [PMID: 29627503 DOI: 10.1016/j.neures.2018.04.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 03/31/2018] [Accepted: 04/02/2018] [Indexed: 11/22/2022]
Abstract
Somal translocation in long bipolar neurons is regulated by actomyosin contractile forces, yet the precise spatiotemporal sites of force generation are unknown. Here we investigate the force dynamics generated during somal translocation using traction force microscopy. Neurons with a short leading process generated a traction force in the growth cone and counteracting forces in the leading and trailing processes. In contrast, neurons with a long leading process generated a force dipole with opposing traction forces in the proximal leading process during nuclear translocation. Transient accumulation of actin filaments was observed at the dipole center of the two opposing forces, which was abolished by inhibition of myosin II activity. A swelling in the leading process emerged and generated a traction force that pulled the nucleus when nuclear translocation was physically hampered. The traction force in the leading process swelling was uncoupled from somal translocation in neurons expressing a dominant negative mutant of the KASH protein, which disrupts the interaction between cytoskeletal components and the nuclear envelope. Our results suggest that the leading process is the site of generation of actomyosin-dependent traction force in long bipolar neurons, and that the traction force is transmitted to the nucleus via KASH proteins.
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86
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Foubet O, Trejo M, Toro R. Mechanical morphogenesis and the development of neocortical organisation. Cortex 2018; 118:315-326. [PMID: 30503630 DOI: 10.1016/j.cortex.2018.03.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 02/07/2018] [Accepted: 03/07/2018] [Indexed: 12/27/2022]
Abstract
The development of complex neocortical organisations is thought to result from the interaction of genetic and activity-dependent processes. We propose that a third type of process - mechanical morphogenesis - may also play an important role. We review theoretical and experimental results in physics showing how even homogeneous growth can produce a variety of forms, in particular neocortical folding. The mechanical instabilities that produce these forms induce heterogeneous patterns of stress at the scale of the organ. We review the evidence showing how these stresses can influence cell proliferation, migration and apoptosis, cell differentiation and shape, migration and axonal guidance, and could thus be able to influence regional neocortical identity and connectivity.
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Affiliation(s)
- Ophélie Foubet
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France; CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France; Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - Miguel Trejo
- Laboratoire de Physique et Mécanique des Milieux Hétérogènes (PMMH), CNRS UMR 7636, ESPCI-ParisTech, Paris Cedex 05, France
| | - Roberto Toro
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France; CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France; Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France.
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87
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Chen WS, Guo LY, Tang CC, Tsai CK, Huang HH, Chin TY, Yang ML, Chen-Yang YW. The Effect of Laminin Surface Modification of Electrospun Silica Nanofiber Substrate on Neuronal Tissue Engineering. NANOMATERIALS 2018. [PMID: 29538349 PMCID: PMC5869656 DOI: 10.3390/nano8030165] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In this study, we first synthesized a slow-degrading silica nanofiber (SNF2) through an electrospun solution with an optimized tetraethyl orthosilicate (TEOS) to polyvinyl pyrrolidone (PVP) ratio. Then, laminin-modified SNF2, namely SNF2-AP-S-L, was obtained through a series of chemical reactions to attach the extracellular matrix protein, laminin, to its surface. The SNF2-AP-S-L substrate was characterized by a combination of scanning electron microscopy (SEM), Fourier transform–infrared (FTIR) spectroscopy, nitrogen adsorption/desorption isotherms, and contact angle measurements. The results of further functional assays show that this substrate is a biocompatible, bioactive and biodegradable scaffold with good structural integrity that persisted beyond 18 days. Moreover, a synergistic effect of sustained structure support and prolonged biochemical stimulation for cell differentiation on SNF2-AP-S-L was found when neuron-like PC12 cells were seeded onto its surface. Specifically, neurite extensions on the covalently modified SNF2-AP-S-L were significantly longer than those observed on unmodified SNF and SNF subjected to physical adsorption of laminin. Together, these results indicate that the SNF2-AP-S-L substrate prepared in this study is a promising 3D biocompatible substrate capable of sustaining longer neuronal growth for tissue-engineering applications.
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Affiliation(s)
- Wen Shuo Chen
- Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Taoyuan 32023, Taiwan.
| | - Ling Yu Guo
- Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Taoyuan 32023, Taiwan.
| | - Chia Chun Tang
- Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Taoyuan 32023, Taiwan.
| | - Cheng Kang Tsai
- Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Taoyuan 32023, Taiwan.
| | - Hui Hua Huang
- Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Taoyuan 32023, Taiwan.
| | - Ting Yu Chin
- Department of Bioscience Technology, Chung Yuan Christian University, Taoyuan 32023, Taiwan.
| | - Mong-Lin Yang
- Department of Science, Concordia University Saint Paul, Saint Paul, MN 55104, USA.
| | - Yui Whei Chen-Yang
- Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Taoyuan 32023, Taiwan.
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88
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Makhija E, Jagielska A, Zhu L, Bost AC, Ong W, Chew SY, Shivashankar GV, Van Vliet KJ. Mechanical Strain Alters Cellular and Nuclear Dynamics at Early Stages of Oligodendrocyte Differentiation. Front Cell Neurosci 2018; 12:59. [PMID: 29559894 PMCID: PMC5845683 DOI: 10.3389/fncel.2018.00059] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 02/19/2018] [Indexed: 11/13/2022] Open
Abstract
Mechanical and physical stimuli including material stiffness and topography or applied mechanical strain have been demonstrated to modulate differentiation of glial progenitor and neural stem cells. Recent studies probing such mechanotransduction in oligodendrocytes have focused chiefly on the biomolecular components. However, the cell-level biophysical changes associated with such responses remain largely unknown. Here, we explored mechanotransduction in oligodendrocyte progenitor cells (OPCs) during the first 48 h of differentiation induction by quantifying the biophysical state in terms of nuclear dynamics, cytoskeleton organization, and cell migration. We compared these mechanophenotypic changes in OPCs exposed to both chemical cues (differentiation factors) and mechanical cues (static tensile strain of 10%) with those exposed to only those chemical cues. We observed that mechanical strain significantly hastened the dampening of nuclear fluctuations and decreased OPC migration, consistent with the progression of differentiation. Those biophysical changes were accompanied by increased production of the intracellular microtubule network. These observations provide insights into mechanisms by which mechanical strain of physiological magnitude could promote differentiation of progenitor cells to oligodendrocytes via inducing intracellular biophysical responses over hours to days post induction.
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Affiliation(s)
- Ekta Makhija
- BioSystems and Micromechanics Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, CREATE, Singapore, Singapore
| | - Anna Jagielska
- BioSystems and Micromechanics Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, CREATE, Singapore, Singapore.,Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Lena Zhu
- BioSystems and Micromechanics Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, CREATE, Singapore, Singapore.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Alexander C Bost
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States.,Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - William Ong
- NTU Institute for Health Technologies (Health Tech NTU), Interdisciplinary Graduate School, Nanyang Technological University, Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Sing Y Chew
- BioSystems and Micromechanics Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, CREATE, Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - G V Shivashankar
- BioSystems and Micromechanics Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, CREATE, Singapore, Singapore.,Mechanobiology Institute, Singapore, Singapore.,The FIRC Institute of Molecular Oncology, Milan, Italy
| | - Krystyn J Van Vliet
- BioSystems and Micromechanics Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, CREATE, Singapore, Singapore.,Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
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89
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Tanaka A, Fujii Y, Kasai N, Okajima T, Nakashima H. Regulation of neuritogenesis in hippocampal neurons using stiffness of extracellular microenvironment. PLoS One 2018; 13:e0191928. [PMID: 29408940 PMCID: PMC5800654 DOI: 10.1371/journal.pone.0191928] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 01/15/2018] [Indexed: 11/19/2022] Open
Abstract
The mechanosensitivity of neurons in the central nervous system (CNS) is an interesting issue as regards understanding neuronal development and designing compliant materials as neural interfaces between neurons and external devices for treating CNS injuries and disorders. Although neurite initiation from a cell body is known to be the first step towards forming a functional nervous network during development or regeneration, less is known about how the mechanical properties of the extracellular microenvironment affect neuritogenesis. Here, we investigated the filamentous actin (F-actin) cytoskeletal structures of neurons, which are a key factor in neuritogenesis, on gel substrates with a stiffness-controlled substrate, to reveal the relationship between substrate stiffness and neuritogenesis. We found that neuritogenesis was significantly suppressed on a gel substrate with an elastic modulus higher than the stiffness of in vivo brain. Fluorescent images of the F-actin cytoskeletal structures showed that the F-actin organization depended on the substrate stiffness. Circumferential actin meshworks and arcs were formed at the edge of the cell body on the stiff gel substrates unlike with soft substrates. The suppression of F-actin cytoskeleton formation improved neuritogenesis. The results indicate that the organization of neuronal F-actin cytoskeletons is strongly regulated by the mechanical properties of the surrounding environment, and the mechanically-induced F-actin cytoskeletons regulate neuritogenesis.
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Affiliation(s)
- Aya Tanaka
- NTT Basic Research Laboratories NTT Corporation, Atsugi, Kanagawa, Japan
- * E-mail:
| | - Yuki Fujii
- Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Nahoko Kasai
- NTT Basic Research Laboratories NTT Corporation, Atsugi, Kanagawa, Japan
| | - Takaharu Okajima
- Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Hiroshi Nakashima
- NTT Basic Research Laboratories NTT Corporation, Atsugi, Kanagawa, Japan
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90
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Tan Z, Parisi C, Di Silvio L, Dini D, Forte AE. Cryogenic 3D Printing of Super Soft Hydrogels. Sci Rep 2017; 7:16293. [PMID: 29176756 PMCID: PMC5701203 DOI: 10.1038/s41598-017-16668-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 11/16/2017] [Indexed: 01/17/2023] Open
Abstract
Conventional 3D bioprinting allows fabrication of 3D scaffolds for biomedical applications. In this contribution we present a cryogenic 3D printing method able to produce stable 3D structures by utilising the liquid to solid phase change of a composite hydrogel (CH) ink. This is achieved by rapidly cooling the ink solution below its freezing point using solid carbon dioxide (CO2) in an isopropanol bath. The setup was able to successfully create 3D complex geometrical structures, with an average compressive stiffness of O(1) kPa (0.49 ± 0.04 kPa stress at 30% compressive strain) and therefore mimics the mechanical properties of the softest tissues found in the human body (e.g. brain and lung). The method was further validated by showing that the 3D printed material was well matched to the cast-moulded equivalent in terms of mechanical properties and microstructure. A preliminary biological evaluation on the 3D printed material, coated with collagen type I, poly-L-lysine and gelatine, was performed by seeding human dermal fibroblasts. Cells showed good attachment and viability on the collagen-coated 3D printed CH. This greatly widens the range of applications for the cryogenically 3D printed CH structures, from soft tissue phantoms for surgical training and simulations to mechanobiology and tissue engineering.
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Affiliation(s)
- Zhengchu Tan
- Department of Mechanical Engineering, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, United Kingdom
| | - Cristian Parisi
- Tissue Engineering and Biophotonics Division, King's College London, Guy's Hospital, Great Maze Pond, London, SE1 9RT, United Kingdom
| | - Lucy Di Silvio
- Tissue Engineering and Biophotonics Division, King's College London, Guy's Hospital, Great Maze Pond, London, SE1 9RT, United Kingdom
| | - Daniele Dini
- Department of Mechanical Engineering, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, United Kingdom
| | - Antonio Elia Forte
- Department of Bioengineering, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, United Kingdom.
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91
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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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92
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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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93
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Mikulska-Ruminska K, Kulik AJ, Benadiba C, Bahar I, Dietler G, Nowak W. Nanomechanics of multidomain neuronal cell adhesion protein contactin revealed by single molecule AFM and SMD. Sci Rep 2017; 7:8852. [PMID: 28821864 PMCID: PMC5562865 DOI: 10.1038/s41598-017-09482-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 07/27/2017] [Indexed: 01/06/2023] Open
Abstract
Contactin-4 (CNTN4) is a complex cell adhesion molecule (CAM) localized at neuronal membranes, playing a key role in maintaining the mechanical integrity and signaling properties of the synapse. CNTN4 consists of six immunoglobulin C2 type (IgC2) domains and four fibronectin type III (FnIII) domains that are shared with many other CAMs. Mutations in CNTN4 gene have been linked to various psychiatric disorders. Toward elucidating the response of this modular protein to mechanical stress, we studied its force-induced unfolding using single molecule atomic force microscopy (smAFM) and steered molecular dynamics (SMD) simulations. Extensive smAFM and SMD data both indicate the distinctive mechanical behavior of the two types of modules distinguished by unique force-extension signatures. The data also reveal the heterogeneity of the response of the individual FNIII and IgC2 modules, which presumably plays a role in the adaptability of CNTN4 to maintaining cell-cell communication and adhesion properties under different conditions. Results show that extensive sampling of force spectra, facilitated by robot-enhanced AFM, can help reveal the existence of weak stabilizing interactions between the domains of multidomain proteins, and provide insights into the nanomechanics of such multidomain or heteromeric proteins.
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Affiliation(s)
- Karolina Mikulska-Ruminska
- Laboratory of Physics of Living Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland. .,Institute of Physics, Faculty of Physics, Astronomy and Applied Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100, Torun, Poland. .,Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Ave, Biomedical Science Tower 3, Pittsburgh, PA, 15213, USA.
| | - Andrej J Kulik
- Laboratory of Physics of Living Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Carine Benadiba
- Laboratory of Physics of Living Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Ivet Bahar
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Ave, Biomedical Science Tower 3, Pittsburgh, PA, 15213, USA.
| | - Giovanni Dietler
- Laboratory of Physics of Living Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Wieslaw Nowak
- Institute of Physics, Faculty of Physics, Astronomy and Applied Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100, Torun, Poland
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94
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Extrinsic mechanical forces mediate retrograde axon extension in a developing neuronal circuit. Nat Commun 2017; 8:282. [PMID: 28819208 PMCID: PMC5561127 DOI: 10.1038/s41467-017-00283-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 06/19/2017] [Indexed: 12/26/2022] Open
Abstract
To form functional neural circuits, neurons migrate to their final destination and extend axons towards their targets. Whether and how these two processes are coordinated in vivo remains elusive. We use the zebrafish olfactory placode as a system to address the underlying mechanisms. Quantitative live imaging uncovers a choreography of directed cell movements that shapes the placode neuronal cluster: convergence of cells towards the centre of the placodal domain and lateral cell movements away from the brain. Axon formation is concomitant with lateral movements and occurs through an unexpected, retrograde mode of extension, where cell bodies move away from axon tips attached to the brain surface. Convergence movements are active, whereas cell body lateral displacements are of mainly passive nature, likely triggered by compression forces from converging neighbouring cells. These findings unravel a previously unknown mechanism of neuronal circuit formation, whereby extrinsic mechanical forces drive the retrograde extension of axons.How neuronal migration and axon growth coordinate during development is only partially understood. Here the authors use quantitative imaging to characterise the morphogenesis of the zebrafish olfactory placode and report an unexpected phenomenon, whereby axons extend through the passive movement of neuron cell bodies away from tethered axon tips.
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95
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Gautam V, Naureen S, Shahid N, Gao Q, Wang Y, Nisbet D, Jagadish C, Daria VR. Engineering Highly Interconnected Neuronal Networks on Nanowire Scaffolds. NANO LETTERS 2017; 17:3369-3375. [PMID: 28437614 DOI: 10.1021/acs.nanolett.6b05288] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Identifying the specific role of physical guidance cues in the growth of neurons is crucial for understanding the fundamental biology of brain development and for designing scaffolds for tissue engineering. Here, we investigate the structural significance of nanoscale topographies as physical cues for neurite outgrowth and circuit formation by growing neurons on semiconductor nanowires. We monitored neurite growth using optical and scanning electron microscopy and evaluated the spontaneous neuronal network activity using functional calcium imaging. We show, for the first time, that an isotropic arrangement of indium phosphide (InP) nanowires can serve as physical cues for guiding neurite growth and aid in forming a network with neighboring neurons. Most importantly, we confirm that multiple neurons, with neurites guided by the topography of the InP nanowire scaffolds, exhibit synchronized calcium activity, implying intercellular communications via synaptic connections. Our study imparts new fundamental insights on the role of nanotopographical cues in the formation of functional neuronal circuits in the brain and will therefore advance the development of neuroprosthetic scaffolds.
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Affiliation(s)
- Vini Gautam
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, ‡Department of Electronic Materials Engineering, Research School of Physics and Engineering, §Laboratory of Advanced Biomaterials, Research School of Engineering, ∥Australian National Fabrication Facility, Research School of Physics and Engineering, Australian National University , Canberra, ACT 2601, Australia
| | - Shagufta Naureen
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, ‡Department of Electronic Materials Engineering, Research School of Physics and Engineering, §Laboratory of Advanced Biomaterials, Research School of Engineering, ∥Australian National Fabrication Facility, Research School of Physics and Engineering, Australian National University , Canberra, ACT 2601, Australia
| | - Naeem Shahid
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, ‡Department of Electronic Materials Engineering, Research School of Physics and Engineering, §Laboratory of Advanced Biomaterials, Research School of Engineering, ∥Australian National Fabrication Facility, Research School of Physics and Engineering, Australian National University , Canberra, ACT 2601, Australia
| | - Qian Gao
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, ‡Department of Electronic Materials Engineering, Research School of Physics and Engineering, §Laboratory of Advanced Biomaterials, Research School of Engineering, ∥Australian National Fabrication Facility, Research School of Physics and Engineering, Australian National University , Canberra, ACT 2601, Australia
| | - Yi Wang
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, ‡Department of Electronic Materials Engineering, Research School of Physics and Engineering, §Laboratory of Advanced Biomaterials, Research School of Engineering, ∥Australian National Fabrication Facility, Research School of Physics and Engineering, Australian National University , Canberra, ACT 2601, Australia
| | - David Nisbet
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, ‡Department of Electronic Materials Engineering, Research School of Physics and Engineering, §Laboratory of Advanced Biomaterials, Research School of Engineering, ∥Australian National Fabrication Facility, Research School of Physics and Engineering, Australian National University , Canberra, ACT 2601, Australia
| | - Chennupati Jagadish
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, ‡Department of Electronic Materials Engineering, Research School of Physics and Engineering, §Laboratory of Advanced Biomaterials, Research School of Engineering, ∥Australian National Fabrication Facility, Research School of Physics and Engineering, Australian National University , Canberra, ACT 2601, Australia
| | - Vincent R Daria
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, ‡Department of Electronic Materials Engineering, Research School of Physics and Engineering, §Laboratory of Advanced Biomaterials, Research School of Engineering, ∥Australian National Fabrication Facility, Research School of Physics and Engineering, Australian National University , Canberra, ACT 2601, Australia
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96
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Kaiser M. Mechanisms of Connectome Development. Trends Cogn Sci 2017; 21:703-717. [PMID: 28610804 DOI: 10.1016/j.tics.2017.05.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 05/12/2017] [Accepted: 05/16/2017] [Indexed: 12/17/2022]
Abstract
At the centenary of D'Arcy Thompson's seminal work 'On Growth and Form', pioneering the description of principles of morphological changes during development and evolution, recent experimental advances allow us to study change in anatomical brain networks. Here, we outline potential principles for connectome development. We will describe recent results on how spatial and temporal factors shape connectome development in health and disease. Understanding the developmental origins of brain diseases in individuals will be crucial for deciding on personalized treatment options. We argue that longitudinal studies, experimentally derived parameters for connection formation, and biologically realistic computational models are needed to better understand the link between brain network development, network structure, and network function.
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Affiliation(s)
- Marcus Kaiser
- ICOS Research Group, School of Computing Science, Newcastle University, Newcastle upon Tyne, UK; Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK.
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97
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Jagielska A, Lowe AL, Makhija E, Wroblewska L, Guck J, Franklin RJM, Shivashankar GV, Van Vliet KJ. Mechanical Strain Promotes Oligodendrocyte Differentiation by Global Changes of Gene Expression. Front Cell Neurosci 2017; 11:93. [PMID: 28473753 PMCID: PMC5397481 DOI: 10.3389/fncel.2017.00093] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 03/20/2017] [Indexed: 11/13/2022] Open
Abstract
Differentiation of oligodendrocyte progenitor cells (OPC) to oligodendrocytes and subsequent axon myelination are critical steps in vertebrate central nervous system (CNS) development and regeneration. Growing evidence supports the significance of mechanical factors in oligodendrocyte biology. Here, we explore the effect of mechanical strains within physiological range on OPC proliferation and differentiation, and strain-associated changes in chromatin structure, epigenetics, and gene expression. Sustained tensile strain of 10-15% inhibited OPC proliferation and promoted differentiation into oligodendrocytes. This response to strain required specific interactions of OPCs with extracellular matrix ligands. Applied strain induced changes in nuclear shape, chromatin organization, and resulted in enhanced histone deacetylation, consistent with increased oligodendrocyte differentiation. This response was concurrent with increased mRNA levels of the epigenetic modifier histone deacetylase Hdac11. Inhibition of HDAC proteins eliminated the strain-mediated increase of OPC differentiation, demonstrating a role of HDACs in mechanotransduction of strain to chromatin. RNA sequencing revealed global changes in gene expression associated with strain. Specifically, expression of multiple genes associated with oligodendrocyte differentiation and axon-oligodendrocyte interactions was increased, including cell surface ligands (Ncam, ephrins), cyto- and nucleo-skeleton genes (Fyn, actinins, myosin, nesprin, Sun1), transcription factors (Sox10, Zfp191, Nkx2.2), and myelin genes (Cnp, Plp, Mag). These findings show how mechanical strain can be transmitted to the nucleus to promote oligodendrocyte differentiation, and identify the global landscape of signaling pathways involved in mechanotransduction. These data provide a source of potential new therapeutic avenues to enhance OPC differentiation in vivo.
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Affiliation(s)
- Anna Jagielska
- Department of Materials Science and Engineering, Massachusetts Institute of TechnologyCambridge, MA, USA
| | - Alexis L Lowe
- Department of Neuroscience, Wellesley CollegeWellesley, MA, USA
| | - Ekta Makhija
- Mechanobiology Institute, National University of SingaporeSingapore, Singapore
| | - Liliana Wroblewska
- Department of Biological Engineering, Massachusetts Institute of TechnologyCambridge, MA, USA
| | - Jochen Guck
- Biotechnology Center, Technische Universität DresdenDresden, Germany
| | - Robin J M Franklin
- Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute and Department of Clinical Neurosciences, University of CambridgeCambridge, UK
| | - G V Shivashankar
- Mechanobiology Institute, National University of SingaporeSingapore, Singapore
| | - Krystyn J Van Vliet
- Department of Materials Science and Engineering, Massachusetts Institute of TechnologyCambridge, MA, USA.,Department of Biological Engineering, Massachusetts Institute of TechnologyCambridge, MA, USA.,BioSystems and Micromechanics Inter-Disciplinary Research Group, Singapore-MIT Alliance for Research and TechnologySingapore, Singapore
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98
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Šmít D, Fouquet C, Pincet F, Zapotocky M, Trembleau A. Axon tension regulates fasciculation/defasciculation through the control of axon shaft zippering. eLife 2017; 6:19907. [PMID: 28422009 PMCID: PMC5478281 DOI: 10.7554/elife.19907] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 04/04/2017] [Indexed: 01/16/2023] Open
Abstract
While axon fasciculation plays a key role in the development of neural networks, very little is known about its dynamics and the underlying biophysical mechanisms. In a model system composed of neurons grown ex vivo from explants of embryonic mouse olfactory epithelia, we observed that axons dynamically interact with each other through their shafts, leading to zippering and unzippering behavior that regulates their fasciculation. Taking advantage of this new preparation suitable for studying such interactions, we carried out a detailed biophysical analysis of zippering, occurring either spontaneously or induced by micromanipulations and pharmacological treatments. We show that zippering arises from the competition of axon-axon adhesion and mechanical tension in the axons, and provide the first quantification of the force of axon-axon adhesion. Furthermore, we introduce a biophysical model of the zippering dynamics, and we quantitatively relate the individual zipper properties to global characteristics of the developing axon network. Our study uncovers a new role of mechanical tension in neural development: the regulation of axon fasciculation.
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Affiliation(s)
- Daniel Šmít
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Coralie Fouquet
- Neuroscience Paris Seine - Institute of Biology Paris Seine, Sorbonne Université, UPMC Univ Paris 06, INSERM, CNRS, Paris, France
| | - Frédéric Pincet
- Laboratoire de Physique Statistique, Ecole Normale Superieure, PSL Research University, Paris, France
| | - Martin Zapotocky
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Alain Trembleau
- Neuroscience Paris Seine - Institute of Biology Paris Seine, Sorbonne Université, UPMC Univ Paris 06, INSERM, CNRS, Paris, France
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99
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Kolesov S, Panteleyev A, Sazhnev M, Kazmin A. DEVELOPING NEW METHODS OF SPINAL CORD INJURY TREATMENT USING MAGNETIC NANOPARTICLES IN COMBINATION WITH ELECTROMAGNETIC FIELD. COLUNA/COLUMNA 2017. [DOI: 10.1590/s1808-185120171602172206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
ABSTRACT Objective: To determine the amount of loss of function after spinal cord transection of varying extents, and whether magnetic iron oxide nanoparticles, in combination with an external magnetic field, improve the rate of subsequent functional recovery in rats. Methods: The animals were divided into groups with 50%, 80% and complete spinal cord transection. The animals of all three study groups were administered magnetic iron oxide nanoparticle suspension to the area of injury. The three control groups were not administered magnetic nanoparticles, but had corresponding transection levels. All animals were exposed to a magnetic field for 4 weeks. Loss of postoperative function and subsequent recovery were assessed using the BBB motor function scale and somatosensory evoked potential monitoring on the first day after surgery, and then weekly. Terminal histological analysis was also conducted in all the groups. Results: The animals in the control or complete transection groups did not demonstrate statistically significant improvement in either the BBB scores or evoked potential amplitude over the four-week period. In the group with 50% transection, however, a statistically significant increase in evoked potential amplitude and BBB scores was observed four weeks after surgery, with the highest increase during the second week of the study. In the group with 80% transection, only improvement in evoked potential amplitude was statistically significant, although less pronounced than in the 50% transection group. Conclusion: The use of magnetic iron oxide nanoparticles in combination with a magnetic field leads to higher rates of functional recovery after spinal cord injury in laboratory animals. The mechanism of this functional improvement needs further investigation.
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Affiliation(s)
- Sergey Kolesov
- N.N. Priorov Federal Scientific Research Institute of Traumatology and Orthopedics, Russia
| | - Andrey Panteleyev
- N.N. Priorov Federal Scientific Research Institute of Traumatology and Orthopedics, Russia
| | - Maxim Sazhnev
- N.N. Priorov Federal Scientific Research Institute of Traumatology and Orthopedics, Russia
| | - Arkadiy Kazmin
- N.N. Priorov Federal Scientific Research Institute of Traumatology and Orthopedics, Russia
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100
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Abstract
Nerves in the mouth of the rorqual whale can double in length during feeding, without incurring damage. Several clever structural features underlie this amazing phenomenon. Such neuroprotective architectural strategies may be conserved, to a lesser extreme, across the organismal spectrum.
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Affiliation(s)
- Sameer B Shah
- Departments of Orthopaedic Surgery and Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA. Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA.
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