1
|
Malong L, Napoli I, Casal G, White IJ, Stierli S, Vaughan A, Cattin AL, Burden JJ, Hng KI, Bossio A, Flanagan A, Zhao HT, Lloyd AC. Characterization of the structure and control of the blood-nerve barrier identifies avenues for therapeutic delivery. Dev Cell 2023; 58:174-191.e8. [PMID: 36706755 DOI: 10.1016/j.devcel.2023.01.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 10/26/2022] [Accepted: 01/04/2023] [Indexed: 01/27/2023]
Abstract
The blood barriers of the nervous system protect neural environments but can hinder therapeutic accessibility. The blood-brain barrier (BBB) is well characterized, consisting of endothelial cells with specialized tight junctions and low levels of transcytosis, properties conferred by contacting pericytes and astrocytes. In contrast, the blood-nerve barrier (BNB) of the peripheral nervous system is poorly defined. Here, we characterize the structure of the mammalian BNB, identify the processes that confer barrier function, and demonstrate how the barrier can be opened in response to injury. The homeostatic BNB is leakier than the BBB, which we show is due to higher levels of transcytosis. However, the barrier is reinforced by macrophages that specifically engulf leaked materials, identifying a role for resident macrophages as an important component of the BNB. Finally, we demonstrate the exploitation of these processes to effectively deliver RNA-targeting therapeutics to peripheral nerves, indicating new treatment approaches for nervous system pathologies.
Collapse
Affiliation(s)
- Liza Malong
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Ilaria Napoli
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Giulia Casal
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Ian J White
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Salome Stierli
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Andrew Vaughan
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Anne-Laure Cattin
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Jemima J Burden
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Keng I Hng
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Alessandro Bossio
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Adrienne Flanagan
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK
| | - Hien T Zhao
- IONIS, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Alison C Lloyd
- UCL Laboratory for Molecular Cell Biology and UCL Cancer Institute, University College London, Gower Street, London, WC1E 6BT, UK.
| |
Collapse
|
2
|
IWANAGA T, TAKAHASHI-IWANAGA H, NIO-KOBAYASHI J, EBARA S. Structure and barrier functions of the perineurium and its relationship with associated sensory corpuscles: A review. Biomed Res 2022; 43:145-159. [DOI: 10.2220/biomedres.43.145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Toshihiko IWANAGA
- Department of Anatomy, Hokkaido University Graduate School of Medicine
| | | | | | | |
Collapse
|
3
|
Petrova ES, Kolos EA. Current Views on Perineurial Cells: Unique Origin, Structure, Functions. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s002209302201001x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
4
|
Zotter B, Dagan O, Brady J, Baloui H, Samanta J, Salzer JL. Gli1 Regulates the Postnatal Acquisition of Peripheral Nerve Architecture. J Neurosci 2022; 42:183-201. [PMID: 34772739 PMCID: PMC8802940 DOI: 10.1523/jneurosci.3096-20.2021] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 10/17/2021] [Accepted: 10/19/2021] [Indexed: 11/21/2022] Open
Abstract
Peripheral nerves are organized into discrete compartments. Axons, Schwann cells (SCs), and endoneurial fibroblasts (EFs) reside within the endoneurium and are surrounded by the perineurium, a cellular sheath comprised of layers of perineurial glia (PNG). SC secretion of Desert Hedgehog (Dhh) regulates this organization. In Dhh nulls, the perineurium is deficient and the endoneurium is subdivided into small compartments termed minifascicles. Human Dhh mutations cause a neuropathy with similar defects. Here we examine the role of Gli1, a canonical transcriptional effector of hedgehog signaling, in regulating peripheral nerve organization in mice of both genders. We identify PNG, EFs, and pericytes as Gli1-expressing cells by genetic fate mapping. Although expression of Dhh by SCs and Gli1 in target cells is coordinately regulated with myelination, Gli1 expression unexpectedly persists in Dhh null EFs. Thus, Gli1 is expressed in EFs noncanonically (i.e., independent of hedgehog signaling). Gli1 and Dhh also have nonredundant activities. Unlike Dhh nulls, Gli1 nulls have a normal perineurium. Like Dhh nulls, Gli1 nulls form minifascicles, which we show likely arise from EFs. Thus, Dhh and Gli1 are independent signals: Gli1 is dispensable for perineurial development but functions cooperatively with Dhh to drive normal endoneurial development. During development, Gli1 also regulates endoneurial extracellular matrix production, nerve vascular organization, and has modest, nonautonomous effects on SC sorting and myelination of axons. Finally, in adult nerves, induced deletion of Gli1 is sufficient to drive minifascicle formation. Thus, Gli1 regulates the development and is required to maintain the endoneurial architecture of peripheral nerves.SIGNIFICANCE STATEMENT Peripheral nerves are organized into distinct cellular/ECM compartments: the epineurium, perineurium, and endoneurium. This organization, with its associated cellular constituents, is critical for the structural and metabolic support of nerves and their response to injury. Here, we show that Gli1, a transcription factor normally expressed downstream of hedgehog signaling, is required for the proper organization of the endoneurium but not the perineurium. Unexpectedly, Gli1 expression by endoneurial cells is independent of, and functions nonredundantly with, Schwann Cell-derived Desert Hedgehog in regulating peripheral nerve architecture. These results further delineate how peripheral nerves acquire their distinctive organization during normal development, and highlight mechanisms that may regulate their reorganization in pathologic settings, including peripheral neuropathies and nerve injury.
Collapse
Affiliation(s)
- Brendan Zotter
- Department of Neuroscience and Physiology, Neuroscience Institute, NYU Langone Medical Center, New York, New York 10016
| | - Or Dagan
- Department of Neuroscience and Physiology, Neuroscience Institute, NYU Langone Medical Center, New York, New York 10016
| | - Jacob Brady
- Department of Neuroscience and Physiology, Neuroscience Institute, NYU Langone Medical Center, New York, New York 10016
| | - Hasna Baloui
- Departments of Neuroscience and Clinical Neuroscience, Karolinska Institutet, Stockholm, 17177, Sweden
| | - Jayshree Samanta
- Department of Comparative Biosciences, School of Veterinary Medicine, Stem Cell and Regenerative Medicine Center, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - James L Salzer
- Department of Neuroscience and Physiology, Neuroscience Institute, NYU Langone Medical Center, New York, New York 10016
| |
Collapse
|
5
|
Yamada A, Nishida Y, Wake K, Nakamura A, Sakamaki Y, Kuwahara H, Uchihara T, Yokota T. OUP accepted manuscript. Microscopy (Oxf) 2022; 71:124-131. [PMID: 35157050 PMCID: PMC8973401 DOI: 10.1093/jmicro/dfac005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 01/10/2022] [Accepted: 02/04/2022] [Indexed: 11/16/2022] Open
Abstract
Precise immunolocalization of molecules in relation to ultrastructural features is challenging, especially when the target is small and not frequent enough to be included in tiny ultrathin sections randomly selected for electron microscopy (EM). Glucose transporter 1 (GLUT1) is in charge of transporting glucose across brain capillary endothelial cells (BCECs). Paraformaldehyde-fixed floating sections (50 μm thick) of mouse brain were immunolabeled with anti-GLUT1 antibody and visualized with fluoronanogold. Fluorescent images encompassing the entire hemisphere were tiled to enable selection of GLUT1-positive BCECs suitable for subsequent EM and landmark placement with laser microdissection to guide trimming. Sections were then fixed with glutaraldehyde, gold enhanced to intensify the labeling and fixed with osmium tetroxide to facilitate ultrastructural recognition. Even though a region that contained target BCECs was successfully trimmed in the resin block, it was only after observation of serial ultrathin sections that GLUT1 signals in coated vesicles on the same cross section corresponding to the cross section preidentified by confocal laser microscope. This is the first ultrastructural demonstration of GLUT1 molecules in coated vesicles, which may well explain its functional relevance to transport glucose across BCECs. Successful ultrastructural localization of molecules in relation to well-preserved target structure in native tissue samples, as achieved in this study, will pave the way to understand the functional relevance of molecules and their relation to ultrastructural details.
Collapse
Affiliation(s)
- Akane Yamada
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Yoichiro Nishida
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Kenjiro Wake
- Liver Research Unit, Minophagen Pharmaceutical Co., Ltd., 3F., Shinjuku Mitsui Building No. 2, 3-2-11, Nishi-Shinjuku Shinjuku-ku, Tokyo 160-0023, Japan
| | - Ayako Nakamura
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Yuriko Sakamaki
- Microscopy Research Support Unit Research Core, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Hiroya Kuwahara
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | | | - Takanori Yokota
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| |
Collapse
|
6
|
Ballard JE, Pall PS, Vardigan J, Zhao F, Holahan MA, Zhou X, Jochnowitz N, Kraus RL, Klein RM, Henze DA, Houghton AK, Burgey CS, Gibson C, Struyk A. Translational Pharmacokinetic–Pharmacodynamic Modeling of NaV1.7 Inhibitor MK-2075 to Inform Human Efficacious Dose. Front Pharmacol 2021; 12:786078. [PMID: 35002718 PMCID: PMC8740778 DOI: 10.3389/fphar.2021.786078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 11/17/2021] [Indexed: 11/21/2022] Open
Abstract
MK-2075 is a small-molecule selective inhibitor of the NaV1.7 channel investigated for the treatment of postoperative pain. A translational strategy was developed for MK-2075 to quantitatively interrelate drug exposure, target modulation, and the desired pharmacological response in preclinical animal models for the purpose of human translation. Analgesics used as a standard of care in postoperative pain were evaluated in preclinical animal models of nociceptive behavior (mouse tail flick latency and rhesus thermode heat withdrawal) to determine the magnitude of pharmacodynamic (PD) response at plasma concentrations associated with efficacy in the clinic. MK-2075 was evaluated in those same animal models to determine the concentration of MK-2075 required to achieve the desired level of response. Translation of MK-2075 efficacious concentrations in preclinical animal models to a clinical PKPD target in humans was achieved by accounting for species differences in plasma protein binding and in vitro potency against the NaV1.7 channel. Estimates of human pharmacokinetic (PK) parameters were obtained from allometric scaling of a PK model from preclinical species and used to predict the dose required to achieve the clinical exposure. MK-2075 exposure–response in a preclinical target modulation assay (rhesus olfaction) was characterized using a computational PKPD model which included a biophase compartment to account for the observed hysteresis. Translation of this model to humans was accomplished by correcting for species differences in PK NaV1.7 potency, and plasma protein binding while assuming that the kinetics of distribution to the target site is the same between humans and rhesus monkeys. This enabled prediction of the level of target modulation anticipated to be achieved over the dosing interval at the projected clinical efficacious human dose. Integration of these efforts into the early development plan informed clinical study design and decision criteria.
Collapse
Affiliation(s)
- Jeanine E. Ballard
- Pharmacokinetics Pharmacodynamics and Drug Metabolism, Merck & Co. Inc., Kenilworth, NJ, United States
- *Correspondence: Jeanine E. Ballard,
| | - Parul S. Pall
- Neuroscience Pharmacology, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Joshua Vardigan
- Neuroscience Pharmacology, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Fuqiang Zhao
- Translational Imaging Biomarkers, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Marie A. Holahan
- Translational Imaging Biomarkers, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Xiaoping Zhou
- Neuroscience Pharmacology, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Nina Jochnowitz
- Neuroscience Pharmacology, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Richard L. Kraus
- Neuroscience Pharmacology, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Rebecca M. Klein
- Neuroscience Pharmacology, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Darrell A. Henze
- Neuroscience Pharmacology, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Andrea K. Houghton
- Neuroscience Pharmacology, Merck & Co. Inc., Kenilworth, NJ, United States
| | | | - Christopher Gibson
- Pharmacokinetics Pharmacodynamics and Drug Metabolism, Merck & Co. Inc., Kenilworth, NJ, United States
| | - Arie Struyk
- Translational Medicine, Merck & Co. Inc., Kenilworth, NJ, United States
| |
Collapse
|
7
|
Gerber D, Pereira JA, Gerber J, Tan G, Dimitrieva S, Yángüez E, Suter U. Transcriptional profiling of mouse peripheral nerves to the single-cell level to build a sciatic nerve ATlas (SNAT). eLife 2021; 10:e58591. [PMID: 33890853 PMCID: PMC8064760 DOI: 10.7554/elife.58591] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 04/13/2021] [Indexed: 12/11/2022] Open
Abstract
Peripheral nerves are organ-like structures containing diverse cell types to optimize function. This interactive assembly includes mostly axon-associated Schwann cells, but also endothelial cells of supporting blood vessels, immune system-associated cells, barrier-forming cells of the perineurium surrounding and protecting nerve fascicles, and connective tissue-resident cells within the intra-fascicular endoneurium and inter-fascicular epineurium. We have established transcriptional profiles of mouse sciatic nerve-inhabitant cells to foster the fundamental understanding of peripheral nerves. To achieve this goal, we have combined bulk RNA sequencing of developing sciatic nerves up to the adult with focused bulk and single-cell RNA sequencing of Schwann cells throughout postnatal development, extended by single-cell transcriptome analysis of the full sciatic nerve both perinatally and in the adult. The results were merged in the transcriptome resource Sciatic Nerve ATlas (SNAT: https://www.snat.ethz.ch). We anticipate that insights gained from our multi-layered analysis will serve as valuable interactive reference point to guide future studies.
Collapse
Affiliation(s)
- Daniel Gerber
- Department of Biology, Institute of Molecular Health Sciences, Swiss Federal Institute of Technology, ETH ZurichZurichSwitzerland
| | - Jorge A Pereira
- Department of Biology, Institute of Molecular Health Sciences, Swiss Federal Institute of Technology, ETH ZurichZurichSwitzerland
| | - Joanne Gerber
- Department of Biology, Institute of Molecular Health Sciences, Swiss Federal Institute of Technology, ETH ZurichZurichSwitzerland
| | - Ge Tan
- Functional Genomics Center Zurich, ETH Zurich/University of ZurichZurichSwitzerland
| | - Slavica Dimitrieva
- Functional Genomics Center Zurich, ETH Zurich/University of ZurichZurichSwitzerland
| | - Emilio Yángüez
- Functional Genomics Center Zurich, ETH Zurich/University of ZurichZurichSwitzerland
| | - Ueli Suter
- Department of Biology, Institute of Molecular Health Sciences, Swiss Federal Institute of Technology, ETH ZurichZurichSwitzerland
| |
Collapse
|
8
|
Mahan MA, Warner WS, Yeoh S, Light A. Rapid-stretch injury to peripheral nerves: implications from an animal model. J Neurosurg 2020; 133:1537-1547. [PMID: 31585426 DOI: 10.3171/2019.6.jns19511] [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: 02/22/2019] [Accepted: 06/13/2019] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Rapid-stretch nerve injuries are among the most devastating lesions to peripheral nerves, yielding unsatisfactory functional outcomes. No animal model has yet been developed that uses only stretch injury for investigation of the pathophysiology of clinical traction injuries. The authors' objective was to define the behavioral and histopathological recovery after graded rapid-stretch nerve injury. METHODS Four groups of male B6.Cg-Tg(Thy1-YFP)HJrs/J mice were tested: sham injury (n = 11); stretch within elastic limits (elastic group, n = 14); stretch beyond elastic limits but before nerve rupture (inelastic group, n = 14); and stretch-ruptured nerves placed in continuity (rupture group, n = 16). Mice were injured at 8 weeks of age, comparable with human late adolescence. Behavioral outcomes were assessed using the sciatic functional index (SFI), tapered-beam dexterity, Von Frey monofilament testing, and the Hargreaves method. Nerve regeneration outcomes were assessed by wet muscle weight and detailed nerve histology after 48 days. RESULTS Post hoc biomechanical assessment of strain and deformation confirmed that the differences between the elastic and inelastic cohorts were statistically significant. After elastic injury, there was a temporary increase in foot faults on the tapered beam (p < 0.01) and mild reduction in monofilament sensitivity, but no meaningful change in SFI, muscle weight, or nerve histology. For inelastic injuries, there was a profound and maintained decrease in SFI (p < 0.001), but recovery of impairment was observed in tapered-beam and monofilament testing by days 15 and 9, respectively. Histologically, axon counts were reduced (p = 0.04), muscle atrophy was present (p < 0.01), and there was moderate neuroma formation on trichrome and immunofluorescent imaging. Stretch-ruptured nerves healed in continuity but without evidence of regeneration. Substantial and continuous impairment was observed in SFI (p < 0.001), tapered beam (p < 0.01), and monofilament (p < 0.01 until day 48). Axon counts (p < 0.001) and muscle weight (p < 0.0001) were significantly reduced, with little evidence of axonal or myelin regeneration concurrent with neuroma formation on immunofluorescent imaging. CONCLUSIONS The 3 biomechanical grades of rapid-stretch nerve injuries displayed consistent and distinct behavioral and histopathological outcomes. Stretch within elastic limits resembled neurapraxic injuries, whereas injuries beyond elastic limits demonstrated axonotmesis coupled with impoverished regeneration and recovery. Rupture injuries uniquely failed to regenerate, despite physical continuity of the nerve. This is the first experimental evidence to correlate stretch severity with functional and histological outcomes. Future studies should focus on the pathophysiological mechanisms that reduce regenerative capacity after stretch injury.
Collapse
Affiliation(s)
- Mark A Mahan
- 1Department of Neurosurgery, Clinical Neurosciences Center, and
| | - Wesley S Warner
- 1Department of Neurosurgery, Clinical Neurosciences Center, and
| | - Stewart Yeoh
- 1Department of Neurosurgery, Clinical Neurosciences Center, and
| | - Alan Light
- 2Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| |
Collapse
|
9
|
Application of Pharmacokinetic-Pharmacodynamic Modeling to Inform Translation of In Vitro NaV1.7 Inhibition to In Vivo Pharmacological Response in Non-human Primate. Pharm Res 2020; 37:181. [PMID: 32888082 PMCID: PMC7473964 DOI: 10.1007/s11095-020-02914-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 08/18/2020] [Indexed: 12/25/2022]
Abstract
Purpose This work describes a staged approach to the application of pharmacokinetic-pharmacodynamic (PK-PD) modeling in the voltage-gated sodium ion channel (NaV1.7) inhibitor drug discovery effort to address strategic questions regarding in vitro to in vivo translation of target modulation. Methods PK-PD analysis was applied to data from a functional magnetic resonance imaging (fMRI) technique to non-invasively measure treatment mediated inhibition of olfaction signaling in non-human primates (NHPs). Initial exposure-response was evaluated using single time point data pooled across 27 compounds to inform on in vitro to in vivo correlation (IVIVC). More robust effect compartment PK-PD modeling was conducted for a subset of 10 compounds with additional PD and PK data to characterize hysteresis. Results The pooled compound exposure-response facilitated an early exploration of IVIVC with a limited dataset for each individual compound, and it suggested a 2.4-fold in vitro to in vivo scaling factor for the NaV1.7 target. Accounting for hysteresis with an effect compartment PK-PD model as compounds advanced towards preclinical development provided a more robust determination of in vivo potency values, which resulted in a statistically significant positive IVIVC with a slope of 1.057 ± 0.210, R-squared of 0.7831, and p value of 0.006. Subsequent simulations with the PK-PD model informed the design of anti-nociception efficacy studies in NHPs. Conclusions A staged approach to PK-PD modeling and simulation enabled integration of in vitro NaV1.7 potency, plasma protein binding, and pharmacokinetics to describe the exposure-response profile and inform future study design as the NaV1.7 inhibitor effort progressed through drug discovery. Electronic supplementary material The online version of this article (10.1007/s11095-020-02914-9) contains supplementary material, which is available to authorized users.
Collapse
|
10
|
Kolarcik CL, Castro CA, Lesniak A, Demetris AJ, Fisher LE, Gaunt RA, Weber DJ, Cui XT. Host tissue response to floating microelectrode arrays chronically implanted in the feline spinal nerve. J Neural Eng 2020; 17:046012. [PMID: 32434161 DOI: 10.1088/1741-2552/ab94d7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Neural interfacing technologies could significantly improve quality of life for people living with the loss of a limb. Both motor commands and sensory feedback must be considered; these complementary systems are segregated from one another in the spinal nerve. APPROACH The dorsal root ganglion-ventral root (DRG-VR) complex was targeted chronically with floating microelectrode arrays designed to record from motor neuron axons in the VR or stimulate sensory neurons in the DRG. Hematoxylin and eosin and Nissl/Luxol fast blue staining were performed. Characterization of the tissue response in regions of interest and pixel-based image analyses were used to quantify MAC387 (monocytes/macrophages), NF200 (axons), S100 (Schwann cells), vimentin (fibroblasts, endothelial cells, astrocytes), and GLUT1 (glucose transport proteins) reactivity. Implanted roots were compared to non-implanted roots and differences between the VR and DRG examined. MAIN RESULTS The tissue response associated with chronic array implantation in this peripheral location is similar to that observed in central nervous system locations. Markers of inflammation were increased in implanted roots relative to control roots with MAC387 positive cells distributed throughout the region corresponding to the device footprint. Significant decreases in neuronal density and myelination were observed in both the VR, which contains only neuronal axons, and the DRG, which contains both neuronal axons and cell bodies. Notably, decreases in NF200 in the VR were observed only at implant times less than ten weeks. Observations related to the blood-nerve barrier and tissue integrity suggest that tissue remodeling occurs, particularly in the VR. SIGNIFICANCE This study was designed to assess the viability of the DRG-VR complex as a site for neural interfacing applications and suggests that continued efforts to mitigate the tissue response will be critical to achieve the overall goal of a long-term, reliable neural interface.
Collapse
Affiliation(s)
- Christi L Kolarcik
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America. Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegic Mellon University, Pittsburgh, PA, United States of America. McGowan Institute for Regenerative Medicine, Pittsburgh, PA, United States of America. Systems Neuroscience Center, Pittsburgh, PA, United States of America. Live Like Lou Center for ALS Research, Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States of America
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Baldauf C, Sondhi M, Shin BC, Ko YE, Ye X, Lee KW, Devaskar SU. Murine maternal dietary restriction affects neural Humanin expression and cellular profile. J Neurosci Res 2019; 98:902-920. [PMID: 31840315 DOI: 10.1002/jnr.24568] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/06/2019] [Accepted: 11/15/2019] [Indexed: 11/10/2022]
Abstract
To understand the cellular basis for the neurodevelopmental effects of intrauterine growth restriction (IUGR), we examined the global and regional expression of various cell types within murine (Mus musculus) fetal brain. Our model employed maternal calorie restriction to 50% daily food intake from gestation day 10-19, producing IUGR offspring. Offspring had smaller head sizes with larger head:body ratios indicating a head sparing IUGR effect. IUGR fetuses at embryonic day 19 (E19) had reduced nestin (progenitors), β-III tubulin (immature neurons), Glial fibrillary acidic protein (astrocytes), and O4 (oligodendrocytes) cell lineages via immunofluorescence quantification and a 30% reduction in cortical thickness. No difference was found in Bcl-2 or Bax (apoptosis) between controls and IUGR, though qualitatively, immunoreactivity of doublecortin (migration) and Ki67 (proliferation) was decreased. In the interest of examining a potential therapeutic peptide, we next investigated a novel pro-survival peptide, mouse Humanin (mHN). Ontogeny examination revealed highest mHN expression at E19, diminishing by postnatal day 15 (P15), and nearly absent in adult (3 months). Subanalysis by sex at E19 yielded higher mHN expression among males during fetal life, without significant difference between sexes postnatally. Furthermore, female IUGR mice at E19 had a greater increase in cortical mHN versus the male fetus over their respective controls. We conclude that maternal dietary restriction-associated IUGR interferes with neural progenitors differentiating into the various cellular components populating the cerebral cortex, and reduces cerebral cortical size. mHN expression is developmental stage and sex specific, with IUGR, particularly in the females, adaptively increasing its expression toward mediating a pro-survival approach against nutritional adversity.
Collapse
Affiliation(s)
- Claire Baldauf
- Department of Pediatrics, Division of Neonatology & Developmental Biology, UCLA Children's Discovery and Innovation Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA, USA
| | - Monica Sondhi
- Department of Pediatrics, Division of Neonatology & Developmental Biology, UCLA Children's Discovery and Innovation Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA, USA
| | - Bo-Chul Shin
- Department of Pediatrics, Division of Neonatology & Developmental Biology, UCLA Children's Discovery and Innovation Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA, USA
| | - Young Eun Ko
- Department of Pediatrics, Division of Neonatology & Developmental Biology, UCLA Children's Discovery and Innovation Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA, USA
| | - Xin Ye
- Department of Pediatrics, Division of Neonatology & Developmental Biology, UCLA Children's Discovery and Innovation Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA, USA
| | - Kuk-Wha Lee
- Department of Pediatrics, Division of Endocrinology, Neonatal Research Center of the UCLA Children's Discovery and Innovation Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA, USA
| | - Sherin U Devaskar
- Department of Pediatrics, Division of Neonatology & Developmental Biology, UCLA Children's Discovery and Innovation Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA, USA
| |
Collapse
|
12
|
Mahan MA, Abou-Al-Shaar H, Karsy M, Warner W, Yeoh S, Palmer CA. Pathologic remodeling in human neuromas: insights from clinical specimens. Acta Neurochir (Wien) 2019; 161:2453-2466. [PMID: 31612277 DOI: 10.1007/s00701-019-04052-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 08/22/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND Neuroma pathology is commonly described as lacking a clear internal structure, but we observed evidence that there are consistent architectural elements. Using human neuroma samples, we sought to identify molecular features that characterize neuroma pathophysiology. METHODS Thirty specimens-12 neuromas-in-continuity (NICs), 11 stump neuromas, two brachial plexus avulsions, and five controls-were immunohistochemically analyzed with antibodies against various components of normal nerve substructures. RESULTS There were no substantial histopathologic differences between stump neuromas and NICs, except that NICs had intact fascicle(s) in the specimen. These intact fascicles showed evidence of injury and fibrosis. On immunohistochemical analysis of the neuromas, laminin demonstrated a consistent double-lumen configuration. The outer lumen stained with GLUT1 antibodies, consistent with perineurium and microfascicle formation. Antibodies to NF200 revealed small clusters of small-diameter axons within the inner lumen, and the anti-S100 antibody showed a relatively regular pattern of non-myelinating Schwann cells. CD68+ cells were only seen in a limited temporal window after injury. T-cells were seen in neuroma specimens, with both a temporal evolution as well as persistence long after injury. Avulsion injury specimens had similar architecture to control nerves. Seven pediatric specimens were not qualitatively different from adult specimens. NICs demonstrated intact but abnormal fascicles that may account for the neurologically impoverished outcomes from untreated NICs. CONCLUSIONS We propose that there is consistent pathophysiologic remodeling after fascicle disruption. Particular features, such as predominance of small caliber axons and persistence of numerous T-cells long after injury, suggest a potential role in chronic pain associated with neuromas.
Collapse
Affiliation(s)
- Mark A Mahan
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA.
| | - Hussam Abou-Al-Shaar
- Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Michael Karsy
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
| | - Wesley Warner
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
| | - Stewart Yeoh
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
| | - Cheryl A Palmer
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| |
Collapse
|
13
|
Jha MK, Morrison BM. Glia-neuron energy metabolism in health and diseases: New insights into the role of nervous system metabolic transporters. Exp Neurol 2018; 309:23-31. [PMID: 30044944 DOI: 10.1016/j.expneurol.2018.07.009] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 07/19/2018] [Accepted: 07/20/2018] [Indexed: 12/16/2022]
Abstract
The brain is, by weight, only 2% the volume of the body and yet it consumes about 20% of the total glucose, suggesting that the energy requirements of the brain are high and that glucose is the primary energy source for the nervous system. Due to this dependence on glucose, brain physiology critically depends on the tight regulation of glucose transport and its metabolism. Glucose transporters ensure efficient glucose uptake by neural cells and contribute to the physiology and pathology of the nervous system. Despite this, a growing body of evidence demonstrates that for the maintenance of several neuronal functions, lactate, rather than glucose, is the preferred energy metabolite in the nervous system. Monocarboxylate transporters play a crucial role in providing metabolic support to axons by functioning as the principal transporters for lactate in the nervous system. Monocarboxylate transporters are also critical for axonal myelination and regeneration. Most importantly, recent studies have demonstrated the central role of glial cells in brain energy metabolism. A close and regulated metabolic conversation between neurons and both astrocytes and oligodendroglia in the central nervous system, or Schwann cells in the peripheral nervous system, has recently been shown to be an important determinant of the metabolism and function of the nervous system. This article reviews the current understanding of the long existing controversies regarding energy substrate and utilization in the nervous system and discusses the role of metabolic transporters in health and diseases of the nervous system.
Collapse
Affiliation(s)
- Mithilesh Kumar Jha
- Department of Neurology, The Johns Hopkins University, Baltimore, MD 21205, United States
| | - Brett M Morrison
- Department of Neurology, The Johns Hopkins University, Baltimore, MD 21205, United States.
| |
Collapse
|
14
|
Gugala Z, Olmsted-Davis EA, Xiong Y, Davis EL, Davis AR. Trauma-Induced Heterotopic Ossification Regulates the Blood-Nerve Barrier. Front Neurol 2018; 9:408. [PMID: 29922221 PMCID: PMC5996108 DOI: 10.3389/fneur.2018.00408] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 05/17/2018] [Indexed: 01/12/2023] Open
Abstract
De novo bone formation can occur in soft tissues as a result of traumatic injury. This process, known as heterotopic ossification (HO), has recently been linked to the peripheral nervous system. Studies suggest that HO may resemble neural crest-derived bone formation and is activated through the release of key bone matrix proteins leading to opening of the blood-nerve barrier (BNB). One of the first steps in this process is the activation of a neuro-inflammatory cascade, which results in migration of chondro-osseous progenitors, and other cells from both the endoneurial and perineurial regions of the peripheral nerves. The perineurial cells undergo brown adipogenesis, to form essential support cells, which regulate expression and activation of matrix metallopeptidase 9 (MMP9) an essential regulatory protein involved in opening the BNB. However, recent studies suggest that, in mice, a key bone matrix protein, bone morphogenetic protein 2 (BMP2) is able to immediately cross the BNB to activate signaling in specific cells within the endoneurial compartment. BMP signaling correlates with bone formation and appears critical for the induction of HO. Surprisingly, several other bone matrix proteins have also been reported to regulate the BNB, leading us to question whether these matrix proteins are important in regulating the BNB. However, this temporary regulation of the BNB does not appear to result in degeneration of the peripheral nerve, but rather may represent one of the first steps in innervation of the newly forming bone.
Collapse
Affiliation(s)
- Zbigniew Gugala
- Department of Orthopedic Surgery and Rehabilitation, University of Texas Medical Branch, Galveston, TX, United States
| | - Elizabeth A. Olmsted-Davis
- Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital and Houston Methodist Hospital, Houston, TX, United States
- Department of Pediatrics – Section Hematology/Oncology, Baylor College of Medicine, Houston, TX, United States
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, United States
| | - Yuqing Xiong
- Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital and Houston Methodist Hospital, Houston, TX, United States
| | - Eleanor L. Davis
- Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital and Houston Methodist Hospital, Houston, TX, United States
| | - Alan R. Davis
- Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital and Houston Methodist Hospital, Houston, TX, United States
- Department of Pediatrics – Section Hematology/Oncology, Baylor College of Medicine, Houston, TX, United States
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, United States
| |
Collapse
|
15
|
Stecker M, Stevenson M. Effects of insulin on peripheral nerves. J Diabetes Complications 2016; 30:770-7. [PMID: 27134033 DOI: 10.1016/j.jdiacomp.2016.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 03/08/2016] [Accepted: 03/14/2016] [Indexed: 12/14/2022]
Abstract
AIMS To assess the effects of insulin on peripheral nerve under normoglycemic and hyperglycemic conditions in the presence and absence of anoxia. METHODS This study uses the in-vitro sciatic nerve model to assess the effect of insulin on peripheral nerve with the nerve action potential (NAP) as an index of nerve function. RESULTS Under normoglycemic conditions, low concentrations of regular insulin (0.01nM) reduced the conduction velocity of oxygenated nerves. Hyperglycemia increased the duration of the NAP and this increase was nearly completely eliminated by insulin in the 0.1nM-100nM concentration range. Insulin (1nM) also had effects on normoglycemic nerves exposed to intermittent anoxia, producing a decrease in the paired-pulse response and NAP amplitude and an increase in peak duration. This was associated with a reduced time to anoxia-induced conduction block. Similar effects were seen when regular insulin was replaced by insulin detemir, but the latter required much higher concentrations. CONCLUSIONS Insulin has concentration dependent effects on the peripheral nerve that are dependent on glucose and anoxia. These effects may be important in modulating neuropathic consequences of diabetes.
Collapse
Affiliation(s)
- Mark Stecker
- Department of Neuroscience, Winthrop University Hospital, Mineola NY 11530.
| | - Matthew Stevenson
- Department of Neuroscience, Winthrop University Hospital, Mineola NY 11530
| |
Collapse
|
16
|
Nerve regeneration: Specific metabolic demands? Exp Neurol 2015; 269:90-2. [DOI: 10.1016/j.expneurol.2015.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 04/01/2015] [Indexed: 10/23/2022]
|
17
|
Morrison BM, Tsingalia A, Vidensky S, Lee Y, Jin L, Farah MH, Lengacher S, Magistretti PJ, Pellerin L, Rothstein JD. Deficiency in monocarboxylate transporter 1 (MCT1) in mice delays regeneration of peripheral nerves following sciatic nerve crush. Exp Neurol 2014; 263:325-38. [PMID: 25447940 DOI: 10.1016/j.expneurol.2014.10.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 10/16/2014] [Accepted: 10/22/2014] [Indexed: 12/20/2022]
Abstract
Peripheral nerve regeneration following injury occurs spontaneously, but many of the processes require metabolic energy. The mechanism of energy supply to axons has not previously been determined. In the central nervous system, monocarboxylate transporter 1 (MCT1), expressed in oligodendroglia, is critical for supplying lactate or other energy metabolites to axons. In the current study, MCT1 is shown to localize within the peripheral nervous system to perineurial cells, dorsal root ganglion neurons, and Schwann cells by MCT1 immunofluorescence in wild-type mice and tdTomato fluorescence in MCT1 BAC reporter mice. To investigate whether MCT1 is necessary for peripheral nerve regeneration, sciatic nerves of MCT1 heterozygous null mice are crushed and peripheral nerve regeneration was quantified electrophysiologically and anatomically. Compound muscle action potential (CMAP) recovery is delayed from a median of 21 days in wild-type mice to greater than 38 days in MCT1 heterozygote null mice. In fact, half of the MCT1 heterozygote null mice have no recovery of CMAP at 42 days, while all of the wild-type mice recovered. In addition, muscle fibers remain 40% more atrophic and neuromuscular junctions 40% more denervated at 42 days post-crush in the MCT1 heterozygote null mice than wild-type mice. The delay in nerve regeneration is not only in motor axons, as the number of regenerated axons in the sural sensory nerve of MCT1 heterozygote null mice at 4 weeks and tibial mixed sensory and motor nerve at 3 weeks is also significantly reduced compared to wild-type mice. This delay in regeneration may be partly due to failed Schwann cell function, as there is reduced early phagocytosis of myelin debris and remyelination of axon segments. These data for the first time demonstrate that MCT1 is critical for regeneration of both sensory and motor axons in mice following sciatic nerve crush.
Collapse
Affiliation(s)
- Brett M Morrison
- Department of Neurology, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA.
| | - Akivaga Tsingalia
- Department of Neurology, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA.
| | - Svetlana Vidensky
- Department of Neurology, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA; Brain Science Institute, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA.
| | - Youngjin Lee
- Department of Neurology, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA; Brain Science Institute, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA.
| | - Lin Jin
- Department of Neurology, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA; Brain Science Institute, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA.
| | - Mohamed H Farah
- Department of Neurology, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA.
| | - Sylvain Lengacher
- Laboratory of Neuroenergetics and Cellular Dynamics, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland.
| | - Pierre J Magistretti
- Division of Biological and Environmental Sciences and Engineering, KAUST, Thuwal, Saudi Arabia; Brain Mind Institute, Ecole Polytechnique Federale de Lausanne, SV2511, Station 19, CH-1015 Lausanne, Switzerland.
| | - Luc Pellerin
- Department of Fundamental Neurosciences, University of Lausanne, 7 Rue du Bugnon, 1005 Lausanne, Switzerland.
| | - Jeffrey D Rothstein
- Department of Neurology, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA; Brain Science Institute, School of Medicine, The Johns Hopkins University, 855 North Wolfe Street, Baltimore, MD 21205, USA.
| |
Collapse
|
18
|
Jensen VFH, Mølck AM, Bøgh IB, Lykkesfeldt J. Effect of insulin-induced hypoglycaemia on the peripheral nervous system: focus on adaptive mechanisms, pathogenesis and histopathological changes. J Neuroendocrinol 2014; 26:482-96. [PMID: 24921897 DOI: 10.1111/jne.12170] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 05/22/2014] [Accepted: 06/05/2014] [Indexed: 12/31/2022]
Abstract
Insulin-induced hypoglycaemia (IIH) is a common acute side effect in type 1 and type 2 diabetic patients, especially during intensive insulin therapy. The peripheral nervous system (PNS) depends on glucose as its primary energy source during normoglycaemia and, consequently, it may be particularly susceptible to IIH damage. Possible mechanisms for adaption of the PNS to IIH include increased glucose uptake, utilisation of alternative energy substrates and the use of Schwann cell glycogen as a local glucose reserve. However, these potential adaptive mechanisms become insufficient when the hypoglycaemic state exceeds a certain level of severity and duration, resulting in a sensory-motor neuropathy with associated skeletal muscle atrophy. Large myelinated motor fibres appear to be particularly vulnerable. Thus, although the PNS is not an obligate glucose consumer, as is the brain, it appears to be more prone to IIH than the central nervous system when hypoglycaemia is not severe (blood glucose level ≤ 2 mm), possibly reflecting a preferential protection of the brain during periods of inadequate glucose availability. With a primary focus on evidence from experimental animal studies investigating nondiabetic IIH, the present review discusses the effect of IIH on the PNS with a focus on adaptive mechanisms, pathogenesis and histological changes.
Collapse
Affiliation(s)
- V F H Jensen
- Department of Veterinary Disease, Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Diabetes Toxicology and Safety Pharmacology, Novo Nordisk A/S, Maaloev, Denmark
| | | | | | | |
Collapse
|
19
|
Abd-El-Hafez AA. Effect of leflunomide on sciatic nerve of adult albino rats. THE EGYPTIAN JOURNAL OF HISTOLOGY 2014; 37:258-268. [DOI: 10.1097/01.ehx.0000446588.04196.df] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
|
20
|
Blood-nerve barrier dysfunction contributes to the generation of neuropathic pain and allows targeting of injured nerves for pain relief. Pain 2014; 155:954-967. [DOI: 10.1016/j.pain.2014.01.026] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 01/15/2014] [Accepted: 01/28/2014] [Indexed: 01/09/2023]
|
21
|
Cura AJ, Carruthers A. Role of monosaccharide transport proteins in carbohydrate assimilation, distribution, metabolism, and homeostasis. Compr Physiol 2013; 2:863-914. [PMID: 22943001 DOI: 10.1002/cphy.c110024] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The facilitated diffusion of glucose, galactose, fructose, urate, myoinositol, and dehydroascorbicacid in mammals is catalyzed by a family of 14 monosaccharide transport proteins called GLUTs. These transporters may be divided into three classes according to sequence similarity and function/substrate specificity. GLUT1 appears to be highly expressed in glycolytically active cells and has been coopted in vitamin C auxotrophs to maintain the redox state of the blood through transport of dehydroascorbate. Several GLUTs are definitive glucose/galactose transporters, GLUT2 and GLUT5 are physiologically important fructose transporters, GLUT9 appears to be a urate transporter while GLUT13 is a proton/myoinositol cotransporter. The physiologic substrates of some GLUTs remain to be established. The GLUTs are expressed in a tissue specific manner where affinity, specificity, and capacity for substrate transport are paramount for tissue function. Although great strides have been made in characterizing GLUT-catalyzed monosaccharide transport and mapping GLUT membrane topography and determinants of substrate specificity, a unifying model for GLUT structure and function remains elusive. The GLUTs play a major role in carbohydrate homeostasis and the redistribution of sugar-derived carbons among the various organ systems. This is accomplished through a multiplicity of GLUT-dependent glucose sensing and effector mechanisms that regulate monosaccharide ingestion, absorption,distribution, cellular transport and metabolism, and recovery/retention. Glucose transport and metabolism have coevolved in mammals to support cerebral glucose utilization.
Collapse
Affiliation(s)
- Anthony J Cura
- Department of Biochemistry & Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | | |
Collapse
|
22
|
|
23
|
Hackel D, Brack A, Fromm M, Rittner H. Modulation of tight junction proteins in the perineurium for regional pain control. Ann N Y Acad Sci 2012; 1257:199-206. [DOI: 10.1111/j.1749-6632.2012.06499.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
24
|
Homeostatic regulation of the endoneurial microenvironment during development, aging and in response to trauma, disease and toxic insult. Acta Neuropathol 2011; 121:291-312. [PMID: 21136068 PMCID: PMC3038236 DOI: 10.1007/s00401-010-0783-x] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 11/15/2010] [Accepted: 11/16/2010] [Indexed: 02/04/2023]
Abstract
The endoneurial microenvironment, delimited by the endothelium of endoneurial vessels and a multi-layered ensheathing perineurium, is a specialized milieu intérieur within which axons, associated Schwann cells and other resident cells of peripheral nerves function. The endothelium and perineurium restricts as well as regulates exchange of material between the endoneurial microenvironment and the surrounding extracellular space and thus is more appropriately described as a blood-nerve interface (BNI) rather than a blood-nerve barrier (BNB). Input to and output from the endoneurial microenvironment occurs via blood-nerve exchange and convective endoneurial fluid flow driven by a proximo-distal hydrostatic pressure gradient. The independent regulation of the endothelial and perineurial components of the BNI during development, aging and in response to trauma is consistent with homeostatic regulation of the endoneurial microenvironment. Pathophysiological alterations of the endoneurium in experimental allergic neuritis (EAN), and diabetic and lead neuropathy are considered to be perturbations of endoneurial homeostasis. The interactions of Schwann cells, axons, macrophages, and mast cells via cell-cell and cell-matrix signaling regulate the permeability of this interface. A greater knowledge of the dynamic nature of tight junctions and the factors that induce and/or modulate these key elements of the BNI will increase our understanding of peripheral nerve disorders as well as stimulate the development of therapeutic strategies to treat these disorders.
Collapse
|
25
|
Abstract
The blood-nerve barrier (BNB) defines the physiological space within which the axons, Schwann cells, and other associated cells of a peripheral nerve function. The BNB consists of the endoneurial microvessels within the nerve fascicle and the investing perineurium. The restricted permeability of these two barriers protects the endoneurial microenvironment from drastic concentration changes in the vascular and other extracellular spaces. It is postulated that endoneurial homeostatic mechanisms regulate the milieu intérieur of peripheral axons and associated Schwann cells. These mechanisms are discussed in relation to nerve development, Wallerian degeneration and nerve regeneration, and lead neuropathy. Finally, the putative factors responsible for the cellular and molecular control of BNB permeability are discussed. Given the dynamic nature of the regulation of the permeability of the perineurium and endoneurial capillaries, it is suggested that the term blood-nerve interface (BNI) better reflects the functional significance of these structures in the maintenance of homeostasis within the endoneurial microenvironment.
Collapse
Affiliation(s)
- Ananda Weerasuriya
- Division of Basic Medical Sciences, School of Medicine, Mercer University, Macon, GA, USA
| | | |
Collapse
|
26
|
Piña-Oviedo S, Del Valle L, Baquera-Heredia J, Ortiz-Hidalgo C. Immunohistochemical characterization of Renaut bodies in superficial digital nerves: further evidence supporting their perineurial cell origin. J Peripher Nerv Syst 2009; 14:22-6. [PMID: 19335536 DOI: 10.1111/j.1529-8027.2009.00202.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Renaut bodies are well-demarcated cylindrical (circular in cross section) hyaline structures attached to the inner layer of the perineurium that can be found in normal and pathological nerves of various animals and humans. They are composed of spidery fibroblasts and perineurial cells immersed in an extracellular matrix that contains randomly oriented collagen fibers and elastin precursors but not axons or Schwann cells. Frequently, they are associated with thickened subperineurial capillaries. As Renaut bodies are mainly located at sites of nerve compression, it is hypothesized they may act as 'protective cushions' for endoneurial components, and that they may be formed as a secondary reaction to trauma. Herein, we report the presence of Renaut bodies within numerous small dermal nerve trunks in an amputated finger. By immunohistochemistry, Renaut bodies expressed markers identical to those of perineurial cells (epithelial membrane antigen, Glut-1, and claudin-1), supporting the concept of a closely associated perineurial but not endoneurial origin. In addition, expression of hypoxia-inducible factor 1 alpha (which has been shown to increase Glut-1 transcription), neurofibromatosis 1 gene related product and NF-2, were also detected in these peripheral nerve structures.
Collapse
Affiliation(s)
- Sergio Piña-Oviedo
- Department of Neuroscience, Neuropathology Core, Temple University School of Medicine, Philadelphia, PA, USA
| | | | | | | |
Collapse
|
27
|
Abstract
Peripheral nerves consist of 3 layers with differing characteristics: the endoneurium, perineurium, and epineurium. The perineurium represents a continuum with the pia-arachnoid from the central nervous system and extends distally with the sheath of capsular cells of peripheral sensorial organs and propioceptive receptors. It is made of layers of flattened cells surrounded by a basement membrane and collagen fibers, forming concentrically laminated structures around single nerve fascicles. Functionally, the perineurium modulates external stretching forces (that could be potentially harmful for nerve fibers), and along with endoneurial vessels, forms the blood-nerve barrier. Multiple pathologic conditions associated with the perineurium have been described. Perineurial invasion is considered an important prognostic factor in several malignant neoplasms. Perineuriomas are true benign infrequent perineurial cell neoplasms that have been divided in 2 categories: those with intraneural localization and a more common extraneural (soft tissue) group, including sclerosing and reticular variants. Sporadic cases of malignant perineuromas have been reported. Interestingly, neurofibromas and malignant peripheral nerve sheath tumors may also display perineurial cell differentiation. The histologic appearance of perineuriomas may overlap with other soft tissue spindle cell neoplasms. Immunohistochemistry is imperative for the diagnosis, although in certain cases ultrastructural studies may be needed. Typical perineuriomas are positive for epithelial membrane antigen, glucose transporter-1-1, and claudin-1, and negative for S-100 protein and neurofilaments. Perineuriomas have mostly simple karyotypes, with one or few chromosomal rearrangements or numerical changes and it seems that specific cytogenetic aberrations may correlate with perineurioma subtype.
Collapse
|
28
|
Takebe K, Nio-Kobayashi J, Takahashi-Iwanaga H, Iwanaga T. Histochemical demonstration of a monocarboxylate transporter in the mouse perineurium with special reference to GLUT1. Biomed Res 2008; 29:297-306. [DOI: 10.2220/biomedres.29.297] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
29
|
Cai Z, Blumbergs PC, Finnie JW, Manavis J, Thompson PD. Novel fibroblastic onion bulbs in a demyelinating avian peripheral neuropathy produced by riboflavin deficiency. Acta Neuropathol 2007; 114:187-94. [PMID: 17357800 DOI: 10.1007/s00401-007-0215-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Revised: 02/20/2007] [Accepted: 02/23/2007] [Indexed: 10/23/2022]
Abstract
The finding of novel fibroblastic onion bulb-like structures in peripheral nerves is reported for the first time in avian riboflavin deficiency. Day old broiler meat chickens were fed a riboflavin deficient diet (1.8 mg/kg) and were killed on postnatal days 6, 11, 16, 21 and 31, whereas control chickens were fed a conventional diet containing 5.0 mg/kg riboflavin. The fibroblastic onion bulb-like structures were found in sciatic and brachial nerves from day 11 onwards and consisted of long cytoplasmic processes of hypertrophied fibroblasts surrounding demyelinated, remyelinated and normally myelinated axons. The fibroblast cytoplasmic processes often enveloped more than one nerve fibre to produce a unique compound-like onion bulb structure. These onion bulb-like structures occurred early in the course of segmental demyelination at the same time as tomacula formation and became increasingly more prominent in the later stages of demyelination and remyelination. The molecular basis of formation of these unique structures requires further study as to the basis of the attraction of the fibroblast processes to nerve fibres associated with myelinating Schwann cells. The model may also be useful in investigating the role of endoneurial fibroblasts in endoneurial fibrosis as the early fibroblastic response in the onion bulbs is distinct from the more usual fibroblastic deposition of collagen in end-stage peripheral nerve disease.
Collapse
Affiliation(s)
- Z Cai
- Hanson Institute Centre for Neurological Diseases, Institute of Medical and Veterinary Science, Adelaide, SA, 5000, Australia
| | | | | | | | | |
Collapse
|
30
|
Matsuzaki T, Ablimit A, Tajika Y, Suzuki T, Aoki T, Hagiwara H, Takata K. Water Channel Aquaporin 1 (AQP1) Is Present in the Perineurium and Perichondrium. Acta Histochem Cytochem 2005. [DOI: 10.1267/ahc.38.37] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Toshiyuki Matsuzaki
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine
| | - Abdushukur Ablimit
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine
| | - Yuki Tajika
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine
| | - Takeshi Suzuki
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine
| | - Takeo Aoki
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine
| | - Haruo Hagiwara
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine
| | - Kuniaki Takata
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine
| |
Collapse
|
31
|
Pummi KP, Heape AM, Grénman RA, Peltonen JTK, Peltonen SA. Tight junction proteins ZO-1, occludin, and claudins in developing and adult human perineurium. J Histochem Cytochem 2004; 52:1037-46. [PMID: 15258179 DOI: 10.1369/jhc.3a6217.2004] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In peripheral nerves, groups of Schwann cell-axon units are isolated from the adjacent tissues by the perineurium, which creates a diffusion barrier responsible for the maintenance of endoneurial homeostasis. The perineurium is formed by concentric layers of overlapping, polygonal perineurial cells that form tight junctions at their interdigitating cell borders. In this study, employing indirect immunofluorescence and immunoelectron microscopy, we demonstrate that claudin-1 and -3, ZO-1, and occludin, but not claudin-2, -4, and -5, are expressed in the perineurium of adult human peripheral nerve. We also describe the expression of occludin, ZO-1, claudin-1, -3, and -5 in the developing human perineurium, showing that the expressions of claudin-1 and -3, ZO-1, and occludin follow similar spatial developmental expression patterns but follow different timetables in achieving their respective adult distributions. Specifically, claudin-1 is already largely restricted to perineurium-derived structures at 11 fetal weeks, whereas claudin-3 and occludin are weakly expressed in the perineurial structures at this age and acquire a well-defined perineurial distribution only between 22 and 35 fetal weeks. ZO-1 appears to acquire its mature profile even later during the third trimester. The results of the present and previous studies show that the perineurial diffusion barrier matures relatively late during human peripheral nerve development.
Collapse
Affiliation(s)
- Kati P Pummi
- Department of Medical Biochemistry and Molecular Biology, University of Turku, Kiinamyllynkatu 10, 20520 Turku, Finland
| | | | | | | | | |
Collapse
|
32
|
Matsuzaki T, Tajika Y, Suzuki T, Aoki T, Hagiwara H, Takata K. Immunolocalization of the water channel, aquaporin-5 (AQP5), in the rat digestive system. ACTA ACUST UNITED AC 2004; 66:307-15. [PMID: 14692686 DOI: 10.1679/aohc.66.307] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Aquaporin-5 (AQP5), an isoform of membrane water channel aquaporins, is expressed in the salivary and lacrimal glands. We surveyed the expression and immunohistochemical localization of AQP5 in the rat digestive system. RT-PCR analysis revealed that AQP5 is expressed in the submandibular gland, tongue, gastric corpus, pyloric region, duodenum, and liver. Immunofluorescence microscopy using AQP5-specific antibodies showed that AQP5 protein is present in the minor salivary glands of the tongue, the pyloric glands, and duodenal glands. To distinguish apical and basolateral domains of the plasma membrane of epithelial cells, double-immunofluorescence staining for AQP5 and tight junction protein occludin was performed. In the minor salivary gland, AQP5 was present in both the serous and mixed secretory end portions. AQP5 was found in the apical membrane of the secretory cells including intercellular secretory canaliculi demarcated with occludin. At higher magnifications, omega-shaped indentations of AQP5 labeling were seen along the apical membrane, suggesting a dynamic process for the apical membrane in exocytosis. Only weak labeling for AQP5 was detected in the basolateral domain. In the stomach, AQP5 was detected in the apical membrane of the pyloric gland secretory cells. In the duodenum, AQP5 was restricted to duodenal glands, where it was localized to the apical membrane. AQP5 was not detected in the intestinal glands or cells in the villi. These observations show that AQP5 is localized mainly in the apical membrane, including intercellular secretory canaliculi of secretory cells in the minor salivary glands, pyloric glands, and duodenal glands. AQP5 appears to play an important role in water transfer in these glands.
Collapse
Affiliation(s)
- Toshiyuki Matsuzaki
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Maebashi, Japan
| | | | | | | | | | | |
Collapse
|