1
|
Wang L, Zhang R, Jiang L, Gao S, Wu J, Jiao Y. Biomaterials as a new option for treating sensorineural hearing loss. Biomater Sci 2024; 12:4006-4023. [PMID: 38979939 DOI: 10.1039/d4bm00518j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Sensorineural hearing loss (SNHL) usually involves damage to complex auditory pathways such as inner ear cells and auditory nerves. The highly intricate and nuanced characteristics of these cells render their repair and regeneration extremely challenging, making it difficult to restore hearing to normal levels once it has been compromised. The effectiveness of traditional drugs is so minimal that they provide little help with the treatment. Fortunately, extensive experiments have demonstrated that combining biomaterials with conventional techniques significantly enhances drug effectiveness. This article reviews the research progress of biomaterials in protecting hair cells and the auditory nerve, repairing genes related to hearing, and developing artificial cochlear materials. By organizing the knowledge presented in this article, perhaps new insights can be provided for the clinical management of SNHL.
Collapse
Affiliation(s)
- Liwen Wang
- Department of Otorhinolaryngology Head and Neck Surgery, Guangzhou Twelfth People's Hospital (The Affiliated Twelfth People's Hospital of Guangzhou Medical University), Guangzhou 510620, China
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
| | - Ruhe Zhang
- Department of Hematology, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen 518107, China
| | - Linlan Jiang
- Department of Otorhinolaryngology Head and Neck Surgery, Guangzhou Twelfth People's Hospital (The Affiliated Twelfth People's Hospital of Guangzhou Medical University), Guangzhou 510620, China
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
| | - Shuyi Gao
- Department of Otorhinolaryngology Head and Neck Surgery, Guangzhou Twelfth People's Hospital (The Affiliated Twelfth People's Hospital of Guangzhou Medical University), Guangzhou 510620, China
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
| | - Jun Wu
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
- Bioscience and Biomedical Engineering Thrust, The Hong Kong University of Science and Technology (Guangzhou), Nansha, Guangzhou 511400, China.
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yuenong Jiao
- Department of Otorhinolaryngology Head and Neck Surgery, Guangzhou Twelfth People's Hospital (The Affiliated Twelfth People's Hospital of Guangzhou Medical University), Guangzhou 510620, China
- Institute of Otorhinolaryngology, Head and Neck Surgery, Guangzhou Medical University, Guangzhou 510620, China.
| |
Collapse
|
2
|
Moya-Alvarado G, Valero-Peña X, Aguirre-Soto A, Bustos FJ, Lazo OM, Bronfman FC. PLC-γ-Ca 2+ pathway regulates axonal TrkB endocytosis and is required for long-distance propagation of BDNF signaling. Front Mol Neurosci 2024; 17:1009404. [PMID: 38660384 PMCID: PMC11040097 DOI: 10.3389/fnmol.2024.1009404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 03/25/2024] [Indexed: 04/26/2024] Open
Abstract
Brain-derived neurotrophic factor (BDNF) and its tropomyosin receptor kinase B (TrkB) are important signaling proteins that regulate dendritic growth and maintenance in the central nervous system (CNS). After binding of BDNF, TrkB is endocytosed into endosomes and continues signaling within the cell soma, dendrites, and axon. In previous studies, we showed that BDNF signaling initiated in axons triggers long-distance signaling, inducing dendritic arborization in a CREB-dependent manner in cell bodies, processes that depend on axonal dynein and TrkB activities. The binding of BDNF to TrkB triggers the activation of different signaling pathways, including the ERK, PLC-γ and PI3K-mTOR pathways, to induce dendritic growth and synaptic plasticity. How TrkB downstream pathways regulate long-distance signaling is unclear. Here, we studied the role of PLC-γ-Ca2+ in BDNF-induced long-distance signaling using compartmentalized microfluidic cultures. We found that dendritic branching and CREB phosphorylation induced by axonal BDNF stimulation require the activation of PLC-γ in the axons of cortical neurons. Locally, in axons, BDNF increases PLC-γ phosphorylation and induces intracellular Ca2+ waves in a PLC-γ-dependent manner. In parallel, we observed that BDNF-containing signaling endosomes transport to the cell body was dependent on PLC-γ activity and intracellular Ca2+ stores. Furthermore, the activity of PLC-γ is required for BDNF-dependent TrkB endocytosis, suggesting a role for the TrkB/PLC-γ signaling pathway in axonal signaling endosome formation.
Collapse
Affiliation(s)
- Guillermo Moya-Alvarado
- Faculty of Biological Sciences, Pontificia Universidad Catolica de Chile (UC), Santiago, Chile
| | - Xavier Valero-Peña
- NeuroSignaling Laboratory, Institute of Biomedical Sciences (ICB), Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Alejandro Aguirre-Soto
- NeuroSignaling Laboratory, Institute of Biomedical Sciences (ICB), Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Fernando J. Bustos
- Constantin-Paton Research Laboratory, Institute of Biomedical Sciences (ICB), Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Oscar M. Lazo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Francisca C. Bronfman
- NeuroSignaling Laboratory, Institute of Biomedical Sciences (ICB), Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| |
Collapse
|
3
|
Finkelstein DS, Du Bois J. Trifunctional Saxitoxin Conjugates for Covalent Labeling of Voltage-Gated Sodium Channels. Chembiochem 2023; 24:e202300493. [PMID: 37746898 PMCID: PMC10863845 DOI: 10.1002/cbic.202300493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/24/2023] [Indexed: 09/26/2023]
Abstract
Voltage-gated sodium ion channels (NaV s) are integral membrane protein complexes responsible for electrical signal conduction in excitable cells. Methods that enable selective labeling of NaV s hold potential value for understanding how channel regulation and post-translational modification are influenced during development and in response to diseases and disorders of the nervous system. We have developed chemical reagents patterned after (+)-saxitoxin (STX) - a potent and reversible inhibitor of multiple NaV isoforms - and affixed with a reactive electrophile and either a biotin cofactor, fluorophore, or 'click' functional group for labeling wild-type channels. Our studies reveal enigmatic structural effects of the probes on the potency and efficiency of covalent protein modification. Among the compounds analyzed, a STX-maleimide-coumarin derivative is most effective at irreversibly blocking Na+ conductance when applied to recombinant NaV s and endogenous channels expressed in hippocampal neurons. Mechanistic analysis supports the conclusion that high-affinity toxin binding is a prerequisite for covalent protein modification. Results from these studies are guiding the development of next-generation tool compounds for selective modification of NaV s expressed in the plasma membranes of cells.
Collapse
Affiliation(s)
- Darren S Finkelstein
- Department of Chemistry, Stanford University, 337 Campus Dr., Stanford, CA 94305, USA
- Present address: Pliant Therapeutics, 260 Littlefield Avenue, South San Francisco, CA 94080, USA
| | - J Du Bois
- Department of Chemistry, Stanford University, 337 Campus Dr., Stanford, CA 94305, USA
| |
Collapse
|
4
|
Vermehren-Schmaedick A, Olah MJ, Ramunno-Johnson D, Lidke KA, Cohen MS, Vu TQ. Molecular-Scale Dynamics of Long Range Retrograde Brain-Derived Neurotrophic Factor Transport Shaped by Cellular Spatial Context. Front Neurosci 2022; 16:835815. [PMID: 35431786 PMCID: PMC9008462 DOI: 10.3389/fnins.2022.835815] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/03/2022] [Indexed: 12/11/2022] Open
Abstract
Retrograde neurotrophin (NT) transport is a specialized form of signal transduction used to conduct information from axons to the cell bodies of central and peripheral nervous system neurons. It is activated upon NT-Trk receptor binding, NT-Trk internalization into signaling endosomes, and their motion along the axon toward the cell body. Brain-derived neurotrophic factor (BDNF) is an abundant NT that modulates key brain and spinal cord functions, and defects in BDNF trafficking are associated with neuronal death, neurodegenerative diseases and in nerve injury. Decades of study have yielded impressive progress in elucidating NT retrograde transport; however, much information remains unclear. For example, while it is known that NT function is dependent on tight control of NT-receptor intracellular trafficking, data describing the precise spatiotemporal molecular dynamics of their axonal to somatic transport are lacking. In past work, we showed the use of discrete, photo-bleaching-resistant quantum dot (QD)-BNDF probes to activate and track BDNF-TrkB receptor internalization; this revealed a rich diversity of molecular motions that intracellular BDNF signaling endosomes undergo within the soma of nodose ganglia sensory neurons. Here, we used combined techniques of discrete QD-BDNF tracking with compartmented microfluidic chambers to characterize retrograde BDNF-TrkB transport over long-ranging distances of primary dorsal root ganglion sensory neuronal axons. Our new findings show that axonal retrograde motion is comprised of heterogeneous mixtures of diffusive behaviors, pauses, and variations in net molecular-motor-dependent transport speeds. Notably, specific molecular dynamic features such as NT speed were dependent on spatial context that could be categorized in distance from distal axons and proximity to the soma and were not entirely dictated by active motor transport speed. The important implication is recognition that NT-receptor retrograde transport is comprised of molecular dynamics, which change over the course of long-range trafficking to shape overall transport and possibly signaling.
Collapse
Affiliation(s)
- Anke Vermehren-Schmaedick
- Department of Biomedical Engineering, Knight Cancer Institute, Oregon Health and Science University, Portland, OR, United States
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Mark J. Olah
- Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM, United States
| | - Damien Ramunno-Johnson
- Department of Biomedical Engineering, Knight Cancer Institute, Oregon Health and Science University, Portland, OR, United States
| | - Keith A. Lidke
- Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM, United States
| | - Michael S. Cohen
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Tania Q. Vu
- Department of Biomedical Engineering, Knight Cancer Institute, Oregon Health and Science University, Portland, OR, United States
- *Correspondence: Tania Q. Vu,
| |
Collapse
|
5
|
Wille I, Harre J, Oehmichen S, Lindemann M, Menzel H, Ehlert N, Lenarz T, Warnecke A, Behrens P. Development of Neuronal Guidance Fibers for Stimulating Electrodes: Basic Construction and Delivery of a Growth Factor. Front Bioeng Biotechnol 2022; 10:776890. [PMID: 35141211 PMCID: PMC8819688 DOI: 10.3389/fbioe.2022.776890] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 01/05/2022] [Indexed: 12/03/2022] Open
Abstract
State-of-the-art treatment for sensorineural hearing loss is based on electrical stimulation of residual spiral ganglion neurons (SGNs) with cochlear implants (CIs). Due to the anatomical gap between the electrode contacts of the CI and the residual afferent fibers of the SGNs, spatial spreading of the stimulation signal hampers focused neuronal stimulation. Also, the efficiency of a CI is limited because SGNs degenerate over time due to loss of trophic support. A promising option to close the anatomical gap is to install fibers as artificial nerve guidance structures on the surface of the implant and install on these fibers drug delivery systems releasing neuroprotective agents. Here, we describe the first steps in this direction. In the present study, suture yarns made of biodegradable polymers (polyglycolide/poly-ε-caprolactone) serve as the basic fiber material. In addition to the unmodified fiber, also fibers modified with amine groups were employed. Cell culture investigations with NIH 3T3 fibroblasts attested good cytocompatibility to both types of fibers. The fibers were then coated with the extracellular matrix component heparan sulfate (HS) as a biomimetic of the extracellular matrix. HS is known to bind, stabilize, modulate, and sustainably release growth factors. Here, we loaded the HS-carrying fibers with the brain-derived neurotrophic factor (BDNF) which is known to act neuroprotectively. Release of this neurotrophic factor from the fibers was followed over a period of 110 days. Cell culture investigations with spiral ganglion cells, using the supernatants from the release studies, showed that the BDNF delivered from the fibers drastically increased the survival rate of SGNs in vitro. Thus, biodegradable polymer fibers with attached HS and loaded with BDNF are suitable for the protection and support of SGNs. Moreover, they present a promising base material for the further development towards a future neuronal guiding scaffold.
Collapse
Affiliation(s)
- Inga Wille
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
- Cluster of Excellence Hearing4all, Hannover, Germany
| | - Jennifer Harre
- Cluster of Excellence Hearing4all, Hannover, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Sarah Oehmichen
- Institut für Technische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Maren Lindemann
- Institut für Technische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Henning Menzel
- Institut für Technische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Nina Ehlert
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
- Cluster of Excellence Hearing4all, Hannover, Germany
| | - Thomas Lenarz
- Cluster of Excellence Hearing4all, Hannover, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Athanasia Warnecke
- Cluster of Excellence Hearing4all, Hannover, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Peter Behrens
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
- Cluster of Excellence Hearing4all, Hannover, Germany
- Cluster of Excellence PhoenixD, Hannover, Germany
| |
Collapse
|
6
|
Surana S, Villarroel‐Campos D, Lazo OM, Moretto E, Tosolini AP, Rhymes ER, Richter S, Sleigh JN, Schiavo G. The evolution of the axonal transport toolkit. Traffic 2019; 21:13-33. [DOI: 10.1111/tra.12710] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/16/2019] [Accepted: 10/17/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Sunaina Surana
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - David Villarroel‐Campos
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - Oscar M. Lazo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
- UK Dementia Research InstituteUniversity College London London UK
| | - Edoardo Moretto
- UK Dementia Research InstituteUniversity College London London UK
| | - Andrew P. Tosolini
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - Elena R. Rhymes
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - Sandy Richter
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - James N. Sleigh
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
- UK Dementia Research InstituteUniversity College London London UK
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
- UK Dementia Research InstituteUniversity College London London UK
- Discoveries Centre for Regenerative and Precision MedicineUniversity College London London UK
| |
Collapse
|
7
|
Killinger BA, Kordower JH. Spreading of alpha-synuclein - relevant or epiphenomenon? J Neurochem 2019; 150:605-611. [PMID: 31152606 DOI: 10.1111/jnc.14779] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/23/2019] [Accepted: 05/27/2019] [Indexed: 01/10/2023]
Abstract
The intracellular accumulation of misfolded alpha-synuclein pathology, termed Lewy pathology, throughout the brain is a phenomenon central to Parkinson's disease pathogenesis. In recent years it has become apparent that Lewy pathology can spread from neuron-to-neuron and between interconnected brain regions. Understanding the phenomenon of Lewy pathology propagation holds great promise in its explanatory power to determine the etiology of Parkinson's disease and related synucleinopathies. However, it remains to be seen if the spread of Lewy pathology is critical for driving this disease. Here we discuss the spreading of Lewy pathology while highlighting some important concepts and experimental observations. We conclude that further studies are required to determine if, and how, the spreading behavior of Lewy pathology is involved in Parkinson's disease. "This article is part of the Special Issue Synuclein".
Collapse
Affiliation(s)
- Bryan A Killinger
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois, USA
| | - Jeffrey H Kordower
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois, USA
| |
Collapse
|
8
|
Growth Factor Delivery Systems for Tissue Engineering and Regenerative Medicine. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1078:245-269. [PMID: 30357627 DOI: 10.1007/978-981-13-0950-2_13] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Growth factors (GFs) are often a key component in tissue engineering and regenerative medicine approaches. In order to fully exploit the therapeutic potential of GFs, GF delivery vehicles have to meet a number of key design criteria such as providing localized delivery and mimicking the dynamic native GF expression levels and patterns. The use of biomaterials as delivery systems is the most successful strategy for controlled delivery and has been translated into different commercially available systems. However, the risk of side effects remains an issue, which is mainly attributed to insufficient control over the release profile. This book chapter reviews the current strategies, chemistries, materials and delivery vehicles employed to overcome the current limitations associated with GF therapies.
Collapse
|
9
|
Vermehren-Schmaedick A, Jacob T, Vu TQ. Methodology for Detecting and Tracking Brain-Derived Neurotrophic Factor Complexes in Neurons Using Single Quantum Dots. BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) 2018. [DOI: 10.1007/7657_2018_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
10
|
Chang TY, Chen C, Lee M, Chang YC, Lu CH, Lu ST, Wang DY, Wang A, Guo CL, Cheng PL. Paxillin facilitates timely neurite initiation on soft-substrate environments by interacting with the endocytic machinery. eLife 2017; 6:31101. [PMID: 29271742 PMCID: PMC5768420 DOI: 10.7554/elife.31101] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 12/20/2017] [Indexed: 12/15/2022] Open
Abstract
Neurite initiation is the first step in neuronal development and occurs spontaneously in soft tissue environments. Although the mechanisms regulating the morphology of migratory cells on rigid substrates in cell culture are widely known, how soft environments modulate neurite initiation remains elusive. Using hydrogel cultures, pharmacologic inhibition, and genetic approaches, we reveal that paxillin-linked endocytosis and adhesion are components of a bistable switch controlling neurite initiation in a substrate modulus-dependent manner. On soft substrates, most paxillin binds to endocytic factors and facilitates vesicle invagination, elevating neuritogenic Rac1 activity and expression of genes encoding the endocytic machinery. By contrast, on rigid substrates, cells develop extensive adhesions, increase RhoA activity and sequester paxillin from the endocytic machinery, thereby delaying neurite initiation. Our results highlight paxillin as a core molecule in substrate modulus-controlled morphogenesis and define a mechanism whereby neuronal cells respond to environments exhibiting varying mechanical properties.
Collapse
Affiliation(s)
- Ting-Ya Chang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Chen Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Min Lee
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Ya-Chu Chang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Chi-Huan Lu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Shao-Tzu Lu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - De-Yao Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Aijun Wang
- Surgical Bioengineering Laboratory, Department of Surgery, University of California, Davis, Davis, United States
| | - Chin-Lin Guo
- Institute of Physics, Academia Sinica, Taipei, Taiwan
| | - Pei-Lin Cheng
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| |
Collapse
|
11
|
Nanotechnological strategies for nerve growth factor delivery: Therapeutic implications in Alzheimer’s disease. Pharmacol Res 2017; 120:68-87. [DOI: 10.1016/j.phrs.2017.03.020] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 02/23/2017] [Accepted: 03/22/2017] [Indexed: 12/30/2022]
|
12
|
Jadhav AD, Wei L, Shi P. Compartmentalized Platforms for Neuro-Pharmacological Research. Curr Neuropharmacol 2016; 14:72-86. [PMID: 26813122 PMCID: PMC4787287 DOI: 10.2174/1570159x13666150516000957] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 04/09/2015] [Accepted: 05/12/2015] [Indexed: 01/09/2023] Open
Abstract
Dissociated primary neuronal cell culture remains an indispensable approach for neurobiology research in order to investigate basic mechanisms underlying diverse neuronal functions, drug screening and pharmacological investigation. Compartmentalization, a widely adopted technique since its emergence in 1970s enables spatial segregation of neuronal segments and detailed investigation that is otherwise limited with traditional culture methods. Although these compartmental chambers (e.g. Campenot chamber) have been proven valuable for the investigation of Peripheral Nervous System (PNS) neurons and to some extent within Central Nervous System (CNS) neurons, their utility has remained limited given the arduous manufacturing process, incompatibility with high-resolution optical imaging and limited throughput. The development in the area of microfabrication and microfluidics has enabled creation of next generation compartmentalized devices that are cheap, easy to manufacture, require reduced sample volumes, enable precise control over the cellular microenvironment both spatially as well as temporally, and permit highthroughput testing. In this review we briefly evaluate the various compartmentalization tools used for neurobiological research, and highlight application of the emerging microfluidic platforms towards in vitro single cell neurobiology.
Collapse
Affiliation(s)
| | | | - Peng Shi
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR.
| |
Collapse
|
13
|
Flux of signalling endosomes undergoing axonal retrograde transport is encoded by presynaptic activity and TrkB. Nat Commun 2016; 7:12976. [PMID: 27687129 PMCID: PMC5427517 DOI: 10.1038/ncomms12976] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 08/23/2016] [Indexed: 01/01/2023] Open
Abstract
Axonal retrograde transport of signalling endosomes from the nerve terminal to the soma underpins survival. As each signalling endosome carries a quantal amount of activated receptors, we hypothesized that it is the frequency of endosomes reaching the soma that determines the scale of the trophic signal. Here we show that upregulating synaptic activity markedly increased the flux of plasma membrane-derived retrograde endosomes (labelled using cholera toxin subunit-B: CTB) in hippocampal neurons cultured in microfluidic devices, and live Drosophila larval motor neurons. Electron and super-resolution microscopy analyses revealed that the fast-moving sub-diffraction-limited CTB carriers contained the TrkB neurotrophin receptor, transiently activated by synaptic activity in a BDNF-independent manner. Pharmacological and genetic inhibition of TrkB activation selectively prevented the coupling between synaptic activity and the retrograde flux of signalling endosomes. TrkB activity therefore controls the encoding of synaptic activity experienced by nerve terminals, digitalized as the flux of retrogradely transported signalling endosomes. Signalling endosomes are known to be essential for neuronal survival. Here the authors show that, in cultured hippocampal neurons and live Drosophila larval motor neurons, neuronal activity increases the retrograde flux of signalling endosomes, and this coupling depends on TrkB activation.
Collapse
|
14
|
Quantum Dot-Based Nanotools for Bioimaging, Diagnostics, and Drug Delivery. Chembiochem 2016; 17:2103-2114. [DOI: 10.1002/cbic.201600357] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Indexed: 12/12/2022]
|
15
|
Gluska S, Chein M, Rotem N, Ionescu A, Perlson E. Tracking Quantum-Dot labeled neurotropic factors transport along primary neuronal axons in compartmental microfluidic chambers. Methods Cell Biol 2016; 131:365-87. [DOI: 10.1016/bs.mcb.2015.06.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
16
|
Maysinger D, Ji J, Hutter E, Cooper E. Nanoparticle-Based and Bioengineered Probes and Sensors to Detect Physiological and Pathological Biomarkers in Neural Cells. Front Neurosci 2015; 9:480. [PMID: 26733793 PMCID: PMC4683200 DOI: 10.3389/fnins.2015.00480] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 11/30/2015] [Indexed: 01/11/2023] Open
Abstract
Nanotechnology, a rapidly evolving field, provides simple and practical tools to investigate the nervous system in health and disease. Among these tools are nanoparticle-based probes and sensors that detect biochemical and physiological properties of neurons and glia, and generate signals proportionate to physical, chemical, and/or electrical changes in these cells. In this context, quantum dots (QDs), carbon-based structures (C-dots, grapheme, and nanodiamonds) and gold nanoparticles are the most commonly used nanostructures. They can detect and measure enzymatic activities of proteases (metalloproteinases, caspases), ions, metabolites, and other biomolecules under physiological or pathological conditions in neural cells. Here, we provide some examples of nanoparticle-based and genetically engineered probes and sensors that are used to reveal changes in protease activities and calcium ion concentrations. Although significant progress in developing these tools has been made for probing neural cells, several challenges remain. We review many common hurdles in sensor development, while highlighting certain advances. In the end, we propose some future directions and ideas for developing practical tools for neural cell investigations, based on the maxim "Measure what is measurable, and make measurable what is not so" (Galileo Galilei).
Collapse
Affiliation(s)
- Dusica Maysinger
- Department of Pharmacology and Therapeutics, McGill University Montreal, QC, Canada
| | - Jeff Ji
- Department of Pharmacology and Therapeutics, McGill University Montreal, QC, Canada
| | - Eliza Hutter
- Department of Pharmacology and Therapeutics, McGill University Montreal, QC, Canada
| | - Elis Cooper
- Department of Physiology, McGill University Montreal, QC, Canada
| |
Collapse
|
17
|
Gibbs KL, Kalmar B, Sleigh JN, Greensmith L, Schiavo G. In vivo imaging of axonal transport in murine motor and sensory neurons. J Neurosci Methods 2015; 257:26-33. [PMID: 26424507 PMCID: PMC4666412 DOI: 10.1016/j.jneumeth.2015.09.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 09/11/2015] [Accepted: 09/16/2015] [Indexed: 12/12/2022]
Abstract
BACKGROUND Axonal transport is essential for neuronal function and survival. Defects in axonal transport have been identified as an early pathological feature in several disorders of the nervous system. The visualisation and quantitative analysis of axonal transport in vivo in rodent models of neurological disease is therefore crucial to improve our understanding of disease pathogenesis and for the identification of novel therapeutics. NEW METHOD Here, we describe a method for the in vivo imaging of axonal transport of signalling endosomes in the sciatic nerve of live, anaesthetised mice. RESULTS This method allows the multiparametric, quantitative analysis of in vivo axonal transport in motor and sensory neurons of adult mice in control conditions and during disease progression. COMPARISON WITH EXISTING METHODS Previous in vivo imaging of the axonal transport of signalling endosomes has been limited to studies in nerve explant preparations or non-invasive approaches using magnetic resonance imaging; techniques that are hampered by major drawbacks such as tissue damage and low temporal and spatial resolution. This new method allows live imaging of the axonal transport of single endosomes in the sciatic nerve in situ and a more sensitive analysis of axonal transport kinetics than previous approaches. CONCLUSIONS The method described in this paper allows an in-depth analysis of the characteristics of axonal transport in both motor and sensory neurons in vivo. It enables the detailed study of alterations in axonal transport in rodent models of neurological diseases and can be used to identify novel pharmacological modifiers of axonal transport.
Collapse
Affiliation(s)
- Katherine L Gibbs
- Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1 N 3BG, UK.
| | - Bernadett Kalmar
- Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1 N 3BG, UK.
| | - James N Sleigh
- Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1 N 3BG, UK; Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK.
| | - Linda Greensmith
- Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1 N 3BG, UK.
| | - Giampietro Schiavo
- Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1 N 3BG, UK.
| |
Collapse
|
18
|
Polak P, Shefi O. Nanometric agents in the service of neuroscience: Manipulation of neuronal growth and activity using nanoparticles. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2015; 11:1467-79. [DOI: 10.1016/j.nano.2015.03.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 03/05/2015] [Accepted: 03/15/2015] [Indexed: 11/29/2022]
|
19
|
Activity-dependent BDNF release via endocytic pathways is regulated by synaptotagmin-6 and complexin. Proc Natl Acad Sci U S A 2015. [PMID: 26216953 DOI: 10.1073/pnas.1511830112] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Brain-derived neurotrophic factor (BDNF) is known to modulate synapse development and plasticity, but the source of synaptic BDNF and molecular mechanisms regulating BDNF release remain unclear. Using exogenous BDNF tagged with quantum dots (BDNF-QDs), we found that endocytosed BDNF-QDs were preferentially localized to postsynaptic sites in the dendrite of cultured hippocampal neurons. Repetitive neuronal spiking induced the release of BDNF-QDs at these sites, and this process required activation of glutamate receptors. Down-regulating complexin 1/2 (Cpx1/2) expression eliminated activity-induced BDNF-QD secretion, although the overall activity-independent secretion was elevated. Among eight synaptotagmin (Syt) isoforms examined, down-regulation of only Syt6 impaired activity-induced BDNF-QD secretion. In contrast, activity-induced release of endogenously synthesized BDNF did not depend on Syt6. Thus, neuronal activity could trigger the release of endosomal BDNF from postsynaptic dendrites in a Cpx- and Syt6-dependent manner, and endosomes containing BDNF may serve as a source of BDNF for activity-dependent synaptic modulation.
Collapse
|
20
|
Weissmiller AM, Natera-Naranjo O, Reyna SM, Pearn ML, Zhao X, Nguyen P, Cheng S, Goldstein LSB, Tanzi RE, Wagner SL, Mobley WC, Wu C. A γ-secretase inhibitor, but not a γ-secretase modulator, induced defects in BDNF axonal trafficking and signaling: evidence for a role for APP. PLoS One 2015; 10:e0118379. [PMID: 25710492 PMCID: PMC4339551 DOI: 10.1371/journal.pone.0118379] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 01/14/2015] [Indexed: 11/19/2022] Open
Abstract
Clues to Alzheimer disease (AD) pathogenesis come from a variety of different sources including studies of clinical and neuropathological features, biomarkers, genomics and animal and cellular models. An important role for amyloid precursor protein (APP) and its processing has emerged and considerable interest has been directed at the hypothesis that Aβ peptides induce changes central to pathogenesis. Accordingly, molecules that reduce the levels of Aβ peptides have been discovered such as γ-secretase inhibitors (GSIs) and modulators (GSMs). GSIs and GSMs reduce Aβ levels through very different mechanisms. However, GSIs, but not GSMs, markedly increase the levels of APP CTFs that are increasingly viewed as disrupting neuronal function. Here, we evaluated the effects of GSIs and GSMs on a number of neuronal phenotypes possibly relevant to their use in treatment of AD. We report that GSI disrupted retrograde axonal trafficking of brain-derived neurotrophic factor (BDNF), suppressed BDNF-induced downstream signaling pathways and induced changes in the distribution within neuronal processes of mitochondria and synaptic vesicles. In contrast, treatment with a novel class of GSMs had no significant effect on these measures. Since knockdown of APP by specific siRNA prevented GSI-induced changes in BDNF axonal trafficking and signaling, we concluded that GSI effects on APP processing were responsible, at least in part, for BDNF trafficking and signaling deficits. Our findings argue that with respect to anti-amyloid treatments, even an APP-specific GSI may have deleterious effects and GSMs may serve as a better alternative.
Collapse
Affiliation(s)
- April M. Weissmiller
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Orlangie Natera-Naranjo
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Sol M. Reyna
- Department of Cellular and Molecular Medicine, University of California San Diego, San Diego, California, United States of America
| | - Matthew L. Pearn
- Department of Anesthesiology, University of California San Diego, San Diego, California, United States of America
- V.A. San Diego Healthcare System, San Diego, California, United States of America
| | - Xiaobei Zhao
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Phuong Nguyen
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Soan Cheng
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Lawrence S. B. Goldstein
- Department of Cellular and Molecular Medicine, University of California San Diego, San Diego, California, United States of America
| | - Rudolph E. Tanzi
- Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts, United States of America
| | - Steven L. Wagner
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - William C. Mobley
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Chengbiao Wu
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| |
Collapse
|
21
|
Marchetti L, Luin S, Bonsignore F, de Nadai T, Beltram F, Cattaneo A. Ligand-induced dynamics of neurotrophin receptors investigated by single-molecule imaging approaches. Int J Mol Sci 2015; 16:1949-79. [PMID: 25603178 PMCID: PMC4307343 DOI: 10.3390/ijms16011949] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 01/05/2015] [Indexed: 01/14/2023] Open
Abstract
Neurotrophins are secreted proteins that regulate neuronal development and survival, as well as maintenance and plasticity of the adult nervous system. The biological activity of neurotrophins stems from their binding to two membrane receptor types, the tropomyosin receptor kinase and the p75 neurotrophin receptors (NRs). The intracellular signalling cascades thereby activated have been extensively investigated. Nevertheless, a comprehensive description of the ligand-induced nanoscale details of NRs dynamics and interactions spanning from the initial lateral movements triggered at the plasma membrane to the internalization and transport processes is still missing. Recent advances in high spatio-temporal resolution imaging techniques have yielded new insight on the dynamics of NRs upon ligand binding. Here we discuss requirements, potential and practical implementation of these novel approaches for the study of neurotrophin trafficking and signalling, in the framework of current knowledge available also for other ligand-receptor systems. We shall especially highlight the correlation between the receptor dynamics activated by different neurotrophins and the respective signalling outcome, as recently revealed by single-molecule tracking of NRs in living neuronal cells.
Collapse
Affiliation(s)
- Laura Marchetti
- National Enterprise for nanoScience and nanoTechnology (NEST) Laboratory, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, Pisa I-56127, Italy.
| | - Stefano Luin
- National Enterprise for nanoScience and nanoTechnology (NEST) Laboratory, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, Pisa I-56127, Italy.
| | - Fulvio Bonsignore
- National Enterprise for nanoScience and nanoTechnology (NEST) Laboratory, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, Pisa I-56127, Italy.
| | - Teresa de Nadai
- Biology Laboratory (BioSNS), Scuola Normale Superiore and Istituto di Neuroscienze-CNR, via Moruzzi 1, Pisa I-56100, Italy.
| | - Fabio Beltram
- National Enterprise for nanoScience and nanoTechnology (NEST) Laboratory, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, Pisa I-56127, Italy.
| | - Antonino Cattaneo
- Biology Laboratory (BioSNS), Scuola Normale Superiore and Istituto di Neuroscienze-CNR, via Moruzzi 1, Pisa I-56100, Italy.
| |
Collapse
|
22
|
Leal G, Afonso PM, Salazar IL, Duarte CB. Regulation of hippocampal synaptic plasticity by BDNF. Brain Res 2014; 1621:82-101. [PMID: 25451089 DOI: 10.1016/j.brainres.2014.10.019] [Citation(s) in RCA: 286] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 10/10/2014] [Accepted: 10/13/2014] [Indexed: 01/01/2023]
Abstract
The neurotrophin brain-derived neurotrophic factor (BDNF) has emerged as a major regulator of activity-dependent plasticity at excitatory synapses in the mammalian central nervous system. In particular, much attention has been given to the role of the neurotrophin in the regulation of hippocampal long-term potentiation (LTP), a sustained enhancement of excitatory synaptic strength believed to underlie learning and memory processes. In this review we summarize the evidence pointing to a role for BDNF in generating functional and structural changes at synapses required for both early- and late phases of LTP in the hippocampus. The available information regarding the pre- and/or postsynaptic release of BDNF and action of the neurotrophin during LTP will be also reviewed. Finally, we discuss the effects of BDNF on the synaptic proteome, either by acting on the protein synthesis machinery and/or by regulating protein degradation by calpains and possibly by the ubiquitin-proteasome system (UPS). This fine-tuned control of the synaptic proteome rather than a simple upregulation of the protein synthesis may play a key role in BDNF-mediated synaptic potentiation. This article is part of a Special Issue entitled SI: Brain and Memory.
Collapse
Affiliation(s)
- Graciano Leal
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Pedro M Afonso
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal; Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Ivan L Salazar
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal; PhD Programme in Experimental Biology and Biomedicine (PDBEB) and Institute for Interdisciplinary Research, University of Coimbra (IIIUC), 3030-789 Coimbra, Portugal
| | - Carlos B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3004-517 Coimbra, Portugal.
| |
Collapse
|
23
|
Zhao X, Zhou Y, Weissmiller AM, Pearn ML, Mobley WC, Wu C. Real-time imaging of axonal transport of quantum dot-labeled BDNF in primary neurons. J Vis Exp 2014:51899. [PMID: 25286194 PMCID: PMC4828072 DOI: 10.3791/51899] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BDNF plays an important role in several facets of neuronal survival, differentiation, and function. Structural and functional deficits in axons are increasingly viewed as an early feature of neurodegenerative diseases, including Alzheimer's disease (AD) and Huntington's disease (HD). As yet unclear is the mechanism(s) by which axonal injury is induced. We reported the development of a novel technique to produce biologically active, monobiotinylated BDNF (mBtBDNF) that can be used to trace axonal transport of BDNF. Quantum dot-labeled BDNF (QD-BDNF) was produced by conjugating quantum dot 655 to mBtBDNF. A microfluidic device was used to isolate axons from neuron cell bodies. Addition of QD-BDNF to the axonal compartment allowed live imaging of BDNF transport in axons. We demonstrated that QD-BDNF moved essentially exclusively retrogradely, with very few pauses, at a moving velocity of around 1.06 μm/sec. This system can be used to investigate mechanisms of disrupted axonal function in AD or HD, as well as other degenerative disorders.
Collapse
Affiliation(s)
- Xiaobei Zhao
- Department of Neurosciences, University of California, San Diego
| | - Yue Zhou
- School of Biomedical Engineering and Med-X Research Institute, Shanghai Jiao Tong University
| | | | - Matthew L Pearn
- Department of Anesthesiology, University of California, San Diego; VA San Diego Healthcare System
| | - William C Mobley
- Department of Neurosciences, University of California, San Diego
| | - Chengbiao Wu
- Department of Neurosciences, University of California, San Diego;
| |
Collapse
|
24
|
Mattei TA, Rehman AA. "Extremely minimally invasive": recent advances in nanotechnology research and future applications in neurosurgery. Neurosurg Rev 2014; 38:27-37; discussion 37. [PMID: 25173621 DOI: 10.1007/s10143-014-0566-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Revised: 05/20/2014] [Accepted: 06/22/2014] [Indexed: 12/25/2022]
Abstract
The term "nanotechnology" refers to the development of materials and devices that have been designed with specific properties at the nanometer scale (10(-9) m), usually being less than 100 nm in size. Recent advances in nanotechnology have promised to enable visualization and intervention at the subcellular level, and its incorporation to future medical therapeutics is expected to bring new avenues for molecular imaging, targeted drug delivery, and personalized interventions. Although the central nervous system presents unique challenges to the implementation of new therapeutic strategies involving nanotechnology (such as the heterogeneous molecular environment of different CNS regions, the existence of multiple processing centers with different cytoarchitecture, and the presence of the blood-brain barrier), numerous studies have demonstrated that the incorporation of nanotechnology resources into the armamentarium of neurosurgery may lead to breakthrough advances in the near future. In this article, the authors present a critical review on the current 'state-of-the-art' of basic research in nanotechnology with special attention to those issues which present the greatest potential to generate major therapeutic progresses in the neurosurgical field, including nanoelectromechanical systems, nano-scaffolds for neural regeneration, sutureless anastomosis, molecular imaging, targeted drug delivery, and theranostic strategies.
Collapse
Affiliation(s)
- Tobias A Mattei
- Department of Neurosurgery, Brain & Spine Center-InvisionHealth/Buffalo-NY, 400 International Dr., Buffalo, NY, ZIP 14221, USA,
| | | |
Collapse
|
25
|
Vermehren-Schmaedick A, Krueger W, Jacob T, Ramunno-Johnson D, Balkowiec A, Lidke KA, Vu TQ. Heterogeneous intracellular trafficking dynamics of brain-derived neurotrophic factor complexes in the neuronal soma revealed by single quantum dot tracking. PLoS One 2014; 9:e95113. [PMID: 24732948 PMCID: PMC3986401 DOI: 10.1371/journal.pone.0095113] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 03/23/2014] [Indexed: 01/19/2023] Open
Abstract
Accumulating evidence underscores the importance of ligand-receptor dynamics in shaping cellular signaling. In the nervous system, growth factor-activated Trk receptor trafficking serves to convey biochemical signaling that underlies fundamental neural functions. Focus has been placed on axonal trafficking but little is known about growth factor-activated Trk dynamics in the neuronal soma, particularly at the molecular scale, due in large part to technical hurdles in observing individual growth factor-Trk complexes for long periods of time inside live cells. Quantum dots (QDs) are intensely fluorescent nanoparticles that have been used to study the dynamics of ligand-receptor complexes at the plasma membrane but the value of QDs for investigating ligand-receptor intracellular dynamics has not been well exploited. The current study establishes that QD conjugated brain-derived neurotrophic factor (QD-BDNF) binds to TrkB receptors with high specificity, activates TrkB downstream signaling, and allows single QD tracking capability for long recording durations deep within the soma of live neurons. QD-BDNF complexes undergo internalization, recycling, and intracellular trafficking in the neuronal soma. These trafficking events exhibit little time-synchrony and diverse heterogeneity in underlying dynamics that include phases of sustained rapid motor transport without pause as well as immobility of surprisingly long-lasting duration (several minutes). Moreover, the trajectories formed by dynamic individual BDNF complexes show no apparent end destination; BDNF complexes can be found meandering over long distances of several microns throughout the expanse of the neuronal soma in a circuitous fashion. The complex, heterogeneous nature of neuronal soma trafficking dynamics contrasts the reported linear nature of axonal transport data and calls for models that surpass our generally limited notions of nuclear-directed transport in the soma. QD-ligand probes are poised to provide understanding of how the molecular mechanisms underlying intracellular ligand-receptor trafficking shape cell signaling under conditions of both healthy and dysfunctional neurological disease models.
Collapse
Affiliation(s)
- Anke Vermehren-Schmaedick
- Department of Biomedical Engineering and Center for Spatial Systems Biomedicine, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Wesley Krueger
- Department of Physics & Astronomy, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Thomas Jacob
- Department of Biomedical Engineering and Center for Spatial Systems Biomedicine, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Damien Ramunno-Johnson
- Department of Biomedical Engineering and Center for Spatial Systems Biomedicine, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Agnieszka Balkowiec
- Department of Integrative Biosciences, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Keith A. Lidke
- Department of Physics & Astronomy, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Tania Q. Vu
- Department of Biomedical Engineering and Center for Spatial Systems Biomedicine, Oregon Health & Science University, Portland, Oregon, United States of America
- * E-mail:
| |
Collapse
|
26
|
Leal G, Comprido D, Duarte CB. BDNF-induced local protein synthesis and synaptic plasticity. Neuropharmacology 2013; 76 Pt C:639-56. [PMID: 23602987 DOI: 10.1016/j.neuropharm.2013.04.005] [Citation(s) in RCA: 442] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Revised: 03/25/2013] [Accepted: 04/03/2013] [Indexed: 12/16/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) is an important regulator of synaptic transmission and long-term potentiation (LTP) in the hippocampus and in other brain regions, playing a role in the formation of certain forms of memory. The effects of BDNF in LTP are mediated by TrkB (tropomyosin-related kinase B) receptors, which are known to be coupled to the activation of the Ras/ERK, phosphatidylinositol 3-kinase/Akt and phospholipase C-γ (PLC-γ) pathways. The role of BDNF in LTP is best studied in the hippocampus, where the neurotrophin acts at pre- and post-synaptic levels. Recent studies have shown that BDNF regulates the transport of mRNAs along dendrites and their translation at the synapse, by modulating the initiation and elongation phases of protein synthesis, and by acting on specific miRNAs. Furthermore, the effect of BDNF on transcription regulation may further contribute to long-term changes in the synaptic proteome. In this review we discuss the recent progress in understanding the mechanisms contributing to the short- and long-term regulation of the synaptic proteome by BDNF, and the role in synaptic plasticity, which is likely to influence learning and memory formation. This article is part of the Special Issue entitled 'BDNF Regulation of Synaptic Structure, Function, and Plasticity'.
Collapse
Affiliation(s)
- Graciano Leal
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3004-517 Coimbra, Portugal
| | | | | |
Collapse
|