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Nheu D, Petratos S. How does Nogo-A signalling influence mitochondrial function during multiple sclerosis pathogenesis? Neurosci Biobehav Rev 2024; 163:105767. [PMID: 38885889 DOI: 10.1016/j.neubiorev.2024.105767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 05/30/2024] [Accepted: 06/08/2024] [Indexed: 06/20/2024]
Abstract
Multiple sclerosis (MS) is a severe neurological disorder that involves inflammation in the brain, spinal cord and optic nerve with key disabling neuropathological outcomes being axonal damage and demyelination. When degeneration of the axo-glial union occurs, a consequence of inflammatory damage to central nervous system (CNS) myelin, dystrophy and death can lead to large membranous structures from dead oligodendrocytes and degenerative myelin deposited in the extracellular milieu. For the first time, this review covers mitochondrial mechanisms that may be operative during MS-related neurodegenerative changes directly activated during accumulating extracellular deposits of myelin associated inhibitory factors (MAIFs), that include the potent inhibitor of neurite outgrowth, Nogo-A. Axonal damage may occur when Nogo-A binds to and signals through its cognate receptor, NgR1, a multimeric complex, to initially stall axonal transport and limit the delivery of important growth-dependent cargo and subcellular organelles such as mitochondria for metabolic efficiency at sites of axo-glial disintegration as a consequence of inflammation. Metabolic efficiency in axons fails during active demyelination and progressive neurodegeneration, preceded by stalled transport of functional mitochondria to fuel axo-glial integrity.
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Affiliation(s)
- Danica Nheu
- Department of Neuroscience, School of Translational Medicine, Monash University, Prahran, VIC 3004, Australia
| | - Steven Petratos
- Department of Neuroscience, School of Translational Medicine, Monash University, Prahran, VIC 3004, Australia.
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2
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Ames S, Adams K, Geisen ME, Stirling DP. Ca 2+-induced myelin pathology precedes axonal spheroid formation and is mediated in part by store-operated Ca 2+ entry after spinal cord injury. Neural Regen Res 2023; 18:2720-2726. [PMID: 37449636 DOI: 10.4103/1673-5374.373656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023] Open
Abstract
The formation of axonal spheroid is a common feature following spinal cord injury. To further understand the source of Ca2+ that mediates axonal spheroid formation, we used our previously characterized ex vivo mouse spinal cord model that allows precise perturbation of extracellular Ca2+. We performed two-photon excitation imaging of spinal cords isolated from Thy1YFP+ transgenic mice and applied the lipophilic dye, Nile red, to record dynamic changes in dorsal column axons and their myelin sheaths respectively. We selectively released Ca2+ from internal stores using the Ca2+ ionophore ionomycin in the presence or absence of external Ca2+. We reported that ionomycin dose-dependently induces pathological changes in myelin and pronounced axonal spheroid formation in the presence of normal 2 mM Ca2+ artificial cerebrospinal fluid. In contrast, removal of external Ca2+ significantly decreased ionomycin-induced myelin and axonal spheroid formation at 2 hours but not at 1 hour after treatment. Using mice that express a neuron-specific Ca2+ indicator in spinal cord axons, we confirmed that ionomycin induced significant increases in intra-axonal Ca2+, but not in the absence of external Ca2+. Periaxonal swelling and the resultant disruption in the axo-myelinic interface often precedes and is negatively correlated with axonal spheroid formation. Pretreatment with YM58483 (500 nM), a well-established blocker of store-operated Ca2+ entry, significantly decreased myelin injury and axonal spheroid formation. Collectively, these data reveal that ionomycin-induced depletion of internal Ca2+ stores and subsequent external Ca2+ entry through store-operated Ca2+ entry contributes to pathological changes in myelin and axonal spheroid formation, providing new targets to protect central myelinated fibers.
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Affiliation(s)
- Spencer Ames
- Kentucky Spinal Cord Injury Research Center; Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY, USA
| | - Kia Adams
- Kentucky Spinal Cord Injury Research Center; Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY, USA
| | - Mariah E Geisen
- Kentucky Spinal Cord Injury Research Center; Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY, USA
| | - David P Stirling
- Kentucky Spinal Cord Injury Research Center; Department of Neurological Surgery; Anatomical Sciences and Neurobiology; Microbiology and Immunology, University of Louisville, School of Medicine, Louisville, KY, USA
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3
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Aydın MŞ, Bay S, Yiğit EN, Özgül C, Oğuz EK, Konuk EY, Ayşit N, Cengiz N, Erdoğan E, Him A, Koçak M, Eroglu E, Öztürk G. Active shrinkage protects neurons following axonal transection. iScience 2023; 26:107715. [PMID: 37701578 PMCID: PMC10493506 DOI: 10.1016/j.isci.2023.107715] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 07/31/2023] [Accepted: 08/22/2023] [Indexed: 09/14/2023] Open
Abstract
Trauma, vascular events, or neurodegenerative processes can lead to axonal injury and eventual transection (axotomy). Neurons can survive axotomy, yet the underlying mechanisms are not fully understood. Excessive water entry into injured neurons poses a particular risk due to swelling and subsequent death. Using in vitro and in vivo neurotrauma model systems based on laser transection and surgical nerve cut, we demonstrated that axotomy triggers actomyosin contraction coupled with calpain activity. As a consequence, neurons shrink acutely to force water out through aquaporin channels preventing swelling and bursting. Inhibiting shrinkage increased the probability of neuronal cell death by about 3-fold. These studies reveal a previously unrecognized cytoprotective response mechanism to neurotrauma and offer a fresh perspective on pathophysiological processes in the nervous system.
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Affiliation(s)
- Mehmet Şerif Aydın
- Regenerative and Restorative Medicine Research Center (REMER), Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul 34810, Türkiye
| | - Sadık Bay
- Regenerative and Restorative Medicine Research Center (REMER), Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul 34810, Türkiye
| | - Esra Nur Yiğit
- Regenerative and Restorative Medicine Research Center (REMER), Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul 34810, Türkiye
| | - Cemil Özgül
- Regenerative and Restorative Medicine Research Center (REMER), Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul 34810, Türkiye
| | - Elif Kaval Oğuz
- Department of Science Education, Faculty of Education, Yüzüncü Yıl University, Van 65080, Türkiye
| | - Elçin Yenidünya Konuk
- Department of Medical Biology, School of Medicine, Bakırçay University, İzmir 35665, Türkiye
| | - Neşe Ayşit
- Regenerative and Restorative Medicine Research Center (REMER), Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul 34810, Türkiye
- Department of Medical Biology and Genetics, School of Medicine, Istanbul Medipol University, Istanbul 34810, Türkiye
| | - Nureddin Cengiz
- Department of Histology and Embryology, School of Medicine, Bandırma Onyedi Eylül University, Bandırma, Balıkesir 10200, Türkiye
| | - Ender Erdoğan
- Department of Histology and Embryology, School of Medicine, Selçuk University, Konya 42130, Türkiye
| | - Aydın Him
- Department of Physiology, School of Medicine, Bolu Abant İzzet Baysal University, Bolu 14030, Türkiye
| | - Mehmet Koçak
- Biostatistics and Bioinformatics Analysis Unit, Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul 34810, Türkiye
- Department of Biostatistics and Medical Informatics, International School of Medicine, Istanbul Medipol University, Istanbul 34810, Türkiye
| | - Emrah Eroglu
- Regenerative and Restorative Medicine Research Center (REMER), Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul 34810, Türkiye
| | - Gürkan Öztürk
- Regenerative and Restorative Medicine Research Center (REMER), Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul 34810, Türkiye
- Department of Physiology, International School of Medicine, Istanbul Medipol University, Istanbul 34810, Türkiye
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4
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Placek LM, Keenan TJ, Coughlan A, Wren AW. Synthesis, Processing and the Effect of Thermal Treatment on the Solubility, Antioxidant Potential and Cytocompatibility of Y2O3 and CeO2 doped SiO2-SrO-Na2O Glass-Ceramics. J Biomater Appl 2022; 37:102-117. [PMID: 35442110 DOI: 10.1177/08853282221078448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Thermal treatment of a 0.52SiO2-0.24SrO-0.24-xNa2O-xMO glass-ceramic series (where x = 0.08 and MO = Y2O3 or CeO2) was conducted in order to synthesize yttrium (Y3+) and cerium (Ce3+) crystalline species that may act as radical oxygen specie (ROS) scavengers. The prominent phase for the Control is a sodium-strontium-silicate while the experimental glass-ceramics (HY, YCe, and HCe) present sodium-Y/Ce-silicate and oxide phases. Disk shrinkage during thermal processing ranges from 1-7% for Control, HY, YCe, and HCe in both diameter and thickness. Solubility studies determined that the release of Si4+ and Na+ are greatest from the Control disks which peaks at 1550 µg/mL. Release from the Y3+ and Ce3+ glass-ceramics reached 320 µg/mL for Si4+ and 630 µg/mL for Na+. The range of antioxidant capacity (ABTS assay) for all samples was 0.31-3.9 mMTE. No significant reduction in MC 3T3 Osteoblast cell viability was observed for any composition tested.
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Affiliation(s)
- Lana M Placek
- Inamori School of Engineering, 1132Alfred University, Alfred, NY, USA
| | - Timothy J Keenan
- Inamori School of Engineering, 1132Alfred University, Alfred, NY, USA
| | - Aisling Coughlan
- Department of Bioengineering, University of Toledo, Toledo, OH, USA
| | - Anthony W Wren
- Inamori School of Engineering, 1132Alfred University, Alfred, NY, USA
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5
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Orem BC, Rajaee A, Stirling DP. Inhibiting Calcium Release from Ryanodine Receptors Protects Axons after Spinal Cord Injury. J Neurotrauma 2022; 39:311-319. [PMID: 34913747 PMCID: PMC8817717 DOI: 10.1089/neu.2021.0350] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Ryanodine receptors (RyRs) mediate calcium release from calcium stores and have been implicated in axonal degeneration. Here, we use an intravital imaging approach to determine axonal fate after spinal cord injury (SCI) in real-time and assess the efficacy of ryanodine receptor inhibition as a potential therapeutic approach to prevent intra-axonal calcium-mediated axonal degeneration. Adult 6-8 week old Thy1YFP transgenic mice that express YFP in axons, as well as triple transgenic Avil-Cre:Ai9:Ai95 mice that express the genetically-encoded calcium indicator GCaMP6f in tdTomato positive axons, were used to visualize axons and calcium changes in axons, respectively. Mice received a mild SCI at the T12 level of the spinal cord. Ryanodine, a RyR antagonist, was given at a concentration of 50 μM intrathecally within 15 min of SCI or delayed 3 h after injury and compared with vehicle-treated mice. RyR inhibition within 15 min of SCI significantly reduced axonal spheroid formation from 1 h to 24 h after SCI and increased axonal survival compared with vehicle controls. Delayed ryanodine treatment increased axonal survival and reduced intra-axonal calcium levels at 24 h after SCI but had no effect on axonal spheroid formation. Together, our results support a role for RyR in secondary axonal degeneration.
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Affiliation(s)
- Ben C. Orem
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Anatomical Sciences and Neurobiology, University of Louisville, School of Medicine, Louisville, Kentucky, USA
| | - Arezoo Rajaee
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, Kentucky, USA
| | - David P. Stirling
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Anatomical Sciences and Neurobiology, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Microbiology and Immunology, University of Louisville, School of Medicine, Louisville, Kentucky, USA
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6
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Ramburrun P, Kumar P, Ndobe E, Choonara YE. Gellan-Xanthan Hydrogel Conduits with Intraluminal Electrospun Nanofibers as Physical, Chemical and Therapeutic Cues for Peripheral Nerve Repair. Int J Mol Sci 2021; 22:ijms222111555. [PMID: 34768986 PMCID: PMC8583980 DOI: 10.3390/ijms222111555] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 10/21/2021] [Indexed: 12/24/2022] Open
Abstract
Optimal levels of functional recovery in peripheral nerve injuries remain elusive due to the architectural complexity of the neuronal environment. Commercial nerve repair conduits lack essential guidance cues for the regenerating axons. In this study, the regenerative potential of a biosimulated nerve repair system providing three types of regenerative cues was evaluated in a 10 mm sciatic nerve-gap model over 4 weeks. A thermo-ionically crosslinked gellan-xanthan hydrogel conduit loaded with electrospun PHBV-magnesium oleate-N-acetyl-cysteine (PHBV-MgOl-NAC) nanofibers was assessed for mechanical properties, nerve growth factor (NGF) release kinetics and PC12 viability. In vivo functional recovery was based on walking track analysis, gastrocnemius muscle mass and histological analysis. As an intraluminal filler, PHBV-MgOl-NAC nanofibers improved matrix resilience, deformation and fracture of the hydrogel conduit. NGF release was sustained over 4 weeks, governed by Fickian diffusion and Case-II relaxational release for the hollow conduit and the nanofiber-loaded conduit, respectively. The intraluminal fibers supported PC12 proliferation by 49% compared to the control, preserved up to 43% muscle mass and gradually improved functional recovery. The combined elements of physical guidance (nanofibrous scaffolding), chemical cues (N-acetyl-cysteine and magnesium oleate) and therapeutic cues (NGF and diclofenac sodium) offers a promising strategy for the regeneration of severed peripheral nerves.
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Affiliation(s)
- Poornima Ramburrun
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, Faculty of Health Sciences, School of Therapeutic Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa; (P.R.); (P.K.)
| | - Pradeep Kumar
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, Faculty of Health Sciences, School of Therapeutic Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa; (P.R.); (P.K.)
| | - Elias Ndobe
- Department of Plastic and Reconstructive Surgery, Faculty of Health Sciences, School of Clinical Medicine, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa;
| | - Yahya E. Choonara
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, Faculty of Health Sciences, School of Therapeutic Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa; (P.R.); (P.K.)
- Correspondence: ; Tel.: +27-11-717-2052
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7
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High Dietary Fat Consumption Impairs Axonal Mitochondrial Function In Vivo. J Neurosci 2021; 41:4321-4334. [PMID: 33785643 DOI: 10.1523/jneurosci.1852-20.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 02/11/2021] [Accepted: 03/15/2021] [Indexed: 01/25/2023] Open
Abstract
Peripheral neuropathy (PN) is the most common complication of prediabetes and diabetes. PN causes severe morbidity for Type 2 diabetes (T2D) and prediabetes patients, including limb pain followed by numbness resulting from peripheral nerve damage. PN in T2D and prediabetes is associated with dyslipidemia and elevated circulating lipids; however, the molecular mechanisms underlying PN development in prediabetes and T2D are unknown. Peripheral nerve sensory neurons rely on axonal mitochondria to provide energy for nerve impulse conduction under homeostatic conditions. Models of dyslipidemia in vitro demonstrate mitochondrial dysfunction in sensory neurons exposed to elevated levels of exogenous fatty acids. Herein, we evaluated the effect of dyslipidemia on mitochondrial function and dynamics in sensory axons of the saphenous nerve of a male high-fat diet (HFD)-fed murine model of prediabetes to identify mitochondrial alterations that correlate with PN pathogenesis in vivo We found that the HFD decreased mitochondrial membrane potential (MMP) in axonal mitochondria and reduced the ability of sensory neurons to conduct at physiological frequencies. Unlike mitochondria in control axons, which dissipated their MMP in response to increased impulse frequency (from 1 to 50 Hz), HFD mitochondria dissipated less MMP in response to axonal energy demand, suggesting a lack of reserve capacity. The HFD also decreased sensory axonal Ca2+ levels and increased mitochondrial lengthening and expression of PGC1α, a master regulator of mitochondrial biogenesis. Together, these results suggest that mitochondrial dysfunction underlies an imbalance of axonal energy and Ca2+ levels and impairs impulse conduction within the saphenous nerve in prediabetic PN.SIGNIFICANCE STATEMENT Diabetes and prediabetes are leading causes of peripheral neuropathy (PN) worldwide. PN has no cure, but development in diabetes and prediabetes is associated with dyslipidemia, including elevated levels of saturated fatty acids. Saturated fatty acids impair mitochondrial dynamics and function in cultured neurons, indicating a role for mitochondrial dysfunction in PN progression; however, the effect of elevated circulating fatty acids on the peripheral nervous system in vivo is unknown. In this study, we identify early pathogenic events in sensory nerve axons of mice with high-fat diet-induced PN, including alterations in mitochondrial function, axonal conduction, and intra-axonal calcium, that provide important insight into potential PN mechanisms associated with prediabetes and dyslipidemia in vivo.
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8
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Changes in the Neurochemical Coding of the Anterior Pelvic Ganglion Neurons Supplying the Male Pig Urinary Bladder Trigone after One-Sided Axotomy of Their Nerve Fibers. Int J Mol Sci 2021; 22:ijms22052231. [PMID: 33668086 PMCID: PMC7956190 DOI: 10.3390/ijms22052231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/15/2021] [Accepted: 02/19/2021] [Indexed: 12/11/2022] Open
Abstract
The present study investigated the effect of unilateral axotomy of urinary bladder trigone (UBT)-projecting nerve fibers from the right anterior pelvic ganglion (APG) on changes in the chemical coding of their neuronal bodies. The study was performed using male pigs with immunohistochemistry and quantitative real-time PCR (qPCR). The animals were divided into a control (C), a morphological (MG) or a molecular biology group (MBG). APG neurons supplying UBT were revealed using the retrograde tracing technique with Fast Blue (FB). Unilateral axotomy resulted in an over 50% decrease in the number of FB+ neurons in both APG ganglia. Immunohistochemistry revealed significant changes in the chemical coding of FB+ cells only in the right ganglion: decreased expression of dopamine-B-hydroxylase (DBH)/tyrosine hydroxylase (TH) and up-regulation of the vesicular acetylcholine transporter (VAChT)/choline acetyltransferase (ChAT), galanin (GAL), vasoactive intestinal polypeptide (VIP) and brain nitric oxide synthase (bNOS). The qPCR results partly corresponded with immunofluorescence findings. In the APGs, genes for VAChT and ChAT, TH and DBH, VIP, and NOS were distinctly down-regulated, while the expression of GAL was up-regulated. Such data may be the basis for further studies concerning the plasticity of these ganglia under experimental or pathological conditions.
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9
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Orem BC, Rajaee A, Stirling DP. IP 3R-mediated intra-axonal Ca 2+ release contributes to secondary axonal degeneration following contusive spinal cord injury. Neurobiol Dis 2020; 146:105123. [PMID: 33011333 DOI: 10.1016/j.nbd.2020.105123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/15/2020] [Accepted: 09/28/2020] [Indexed: 01/11/2023] Open
Abstract
Secondary axonal loss contributes to the persistent functional disability following trauma. Consequently, preserving axons following spinal cord injury (SCI) is a major therapeutic goal to improve neurological outcome; however, the complex molecular mechanisms that mediate secondary axonal degeneration remain unclear. We previously showed that IP3R-mediated Ca2+ release contributes to axonal dieback and axonal loss following an ex vivo laser-induced SCI. Nevertheless, targeting IP3R in a clinically relevant in vivo model of SCI and determining its contribution to secondary axonal degeneration has yet to be explored. Here we used intravital two-photon excitation microscopy to assess the role of IP3R in secondary axonal degeneration in real-time after a contusive-SCI in vivo. To visualize Ca2+ changes specifically in spinal axons over time, adult 6-8 week-old triple transgenic Avil-Cre:Ai9:Ai95 (sensory neuron-specific expression of tdTomato and the genetic calcium indicator GCaMP6f) mice were subjected to a mild (30 kdyn) T12 contusive-SCI and received delayed treatment with the IP3R blocker 2-APB (100 μM, intrathecal delivery at 3, and 24 h following injury) or vehicle control. To determine the IP3R subtype involved, we knocked-down IP3R3 using capped phosphodiester oligonucleotides. Delayed treatment with 2-APB significantly reduced axonal spheroids, increased axonal survival, and reduced intra-axonal Ca2+ accumulation within dorsal column axons at 24 h following SCI in vivo. Additionally, knockdown of IP3R3 yielded increased axon survival 24 h post-SCI. These results suggest that IP3R-mediated Ca2+ release contributes to secondary axonal degeneration in vivo following SCI.
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Affiliation(s)
- Ben C Orem
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Anatomical Sciences and Neurobiology, University of Louisville, School of Medicine, Louisville, KY 40202, USA
| | - Arezoo Rajaee
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Departments of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY 40202, USA
| | - David P Stirling
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Departments of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Anatomical Sciences and Neurobiology, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Microbiology and Immunology, University of Louisville, School of Medicine, Louisville, KY 40202, USA.
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10
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Zhai X, Li J, Li L, Sun Y, Zhang X, Xue Y, Lv J, Gao Y, Li S, Yan W, Yin S, Xiao Z. L-lactate preconditioning promotes plasticity-related proteins expression and reduces neurological deficits by potentiating GPR81 signaling in rat traumatic brain injury model. Brain Res 2020; 1746:146945. [PMID: 32531223 DOI: 10.1016/j.brainres.2020.146945] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/02/2020] [Accepted: 06/03/2020] [Indexed: 01/16/2023]
Abstract
Currently, there is no efficacious pharmacological treatment for traumatic brain injury (TBI). Previous studies revealed that L-lactate preconditioning has shown rich neuroprotective effects against cerebral ischemia, and therefore has the potential to improve neurological outcomes after TBI. L-lactate played a neuroprotective role by activating GPR81 in diseases of the central nervous system (CNS) such as TBI and cerebral ischemia. In this study we investigated the effects of L-lactate preconditioning on TBI and explored the underlying mechanisms. In this study, the mNSS test revealed that L-lactate preconditioning alleviates the neurological deficit caused by TBI in rats. L-lactate preconditioning significantly increased the expression of GPR81, PSD95, GAP43, BDNF, and MCT2 24 h after TBI in the cortex and hippocampus compared with the sham group. Taken together, these data suggested that L-lactate preconditioning is an effective method with which to recover neurological function after TBI. This reveals the mechanism of L-lactate preconditioning on TBI and provides a potential therapeutic method for TBI in humans.
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Affiliation(s)
- Xiuli Zhai
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, China
| | - Jinying Li
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, China
| | - Liya Li
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, China
| | - Ye Sun
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, China
| | - Xiaonan Zhang
- Department of Physiology, Dalian Medical University, Dalian 116044, China
| | - Ying Xue
- Department of Physiology, Dalian Medical University, Dalian 116044, China
| | - Jiaxin Lv
- Department of Anesthesiology, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Ye Gao
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, China
| | - Shouxin Li
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, China
| | - Wei Yan
- Department of Physiology, Dalian Medical University, Dalian 116044, China
| | - Shengming Yin
- Department of Physiology, Dalian Medical University, Dalian 116044, China.
| | - Zhaoyang Xiao
- Department of Anesthesiology, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, China.
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11
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Kangiser MM, Thomas AM, Kaiver CM, Lisdahl KM. Nicotine Effects on White Matter Microstructure in Young Adults. Arch Clin Neuropsychol 2020; 35:10-21. [PMID: 31009035 DOI: 10.1093/arclin/acy101] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 03/11/2018] [Accepted: 12/06/2018] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE Nicotine use is widely prevalent among youth, and is associated with white matter microstructural changes as measured by diffusion tensor imaging (DTI). In adults, nicotine use is generally associated with lower fractional anisotropy (FA), but in adolescents/young adults (≤30 years), microstructure appears healthier, indicated by higher FA. This cross-sectional study examined associations between nicotine use and white matter microstructure using fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) in young adults. METHODS Fifty-three participants (18 nicotine users [10 female]/35 controls [17 female]) ages 18-25 underwent MRI scan, neuropsychological battery, toxicology screening, and drug use interview. Nicotine group associations with FA and MD were examined in various white matter tracts. In significant tracts, AD and RD were measured. Exploratory correlations were conducted between significant tracts and verbal memory and sustained attention/working memory performance. RESULTS Nicotine users exhibited significantly lower FA than controls in the left anterior thalamic radiation, left inferior longitudinal fasciculus, left superior longitudinal fasciculus-temporal, and left uncinate fasciculus. In these tracts, AD and RD did not differ, nor did MD differ in any tract. White matter quality was positively correlated with sustained attention/working memory performance. CONCLUSIONS Cigarette smoking may disrupt white matter microstructure. These results are consistent with adult studies, but inconsistent with adolescent/young adult studies, likely due to methodological and sample age differences. Further studies should examine longitudinal effects of nicotine use on white matter microstructure in a larger sample.
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Affiliation(s)
- Megan M Kangiser
- University of Wisconsin-Milwaukee, Department of Psychology, Milwaukee, WI, USA
| | - Alicia M Thomas
- University of Wisconsin-Milwaukee, Department of Psychology, Milwaukee, WI, USA
| | - Christine M Kaiver
- University of Wisconsin-Milwaukee, Department of Psychology, Milwaukee, WI, USA
| | - Krista M Lisdahl
- University of Wisconsin-Milwaukee, Department of Psychology, Milwaukee, WI, USA
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12
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Rajaee A, Geisen ME, Sellers AK, Stirling DP. Repeat intravital imaging of the murine spinal cord reveals degenerative and reparative responses of spinal axons in real-time following a contusive SCI. Exp Neurol 2020; 327:113258. [PMID: 32105708 DOI: 10.1016/j.expneurol.2020.113258] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 02/06/2020] [Accepted: 02/22/2020] [Indexed: 12/18/2022]
Abstract
Spinal cord injury (SCI) induces a secondary degenerative response that causes the loss of spared axons and worsens neurological outcome. The complex molecular mechanisms that mediate secondary axonal degeneration remain poorly understood. To further our understanding of secondary axonal degeneration following SCI, we assessed the spatiotemporal dynamics of axonal spheroid and terminal bulb formation following a contusive SCI in real-time in vivo. Adult 6-8 week old Thy1YFP transgenic mice underwent a T12 laminectomy for acute imaging sessions or were implanted with a custom spinal cord imaging chamber for chronic imaging of the spinal cord. Two-photon excitation time-lapse microscopy was performed prior to a mild contusion SCI (30 kilodyne, IH Impactor) and at 1-4 h and 1-14 days post-SCI. We quantified the number of axonal spheroids, their size and distribution, the number of endbulbs, and axonal survival from 1 h to 14 days post-SCI. Our data reveal that the majority of axons underwent swelling and axonal spheroid formation acutely after SCI resulting in the loss of ~70% of axons by 1 day after injury. In agreement, the number of axonal spheroids rapidly increased at 1 h after SCI and remained significantly elevated up to 14 days after SCI. Furthermore, the distribution of axonal spheroids spread mediolaterally over time indicative of delayed secondary degenerative processes. In contrast, axonal endbulbs were relatively sparse and their numbers peaked at 1 day after injury. Intriguingly, axonal survival significantly increased at 7 and 14 days compared to 3 days after SCI revealing a potential endogenous axonal repair process that mirrors the known spontaneous functional recovery after SCI. In support, ~43% of tracked axonal spheroids resolved over the course of observation revealing their dynamic nature. Furthermore, axonal spheroids and endbulbs accumulated mitochondria and excessive tubulin polyglutamylation suggestive of disrupted axonal transport as a shared mechanism. Collectively, this study provides important insight into both degenerative and recoverable responses of axons following contusive SCI in real-time. Understanding how axons spontaneously recover after SCI will be an important avenue for future SCI research and may help guide future clinical trials.
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Affiliation(s)
- Arezoo Rajaee
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY 40202, USA
| | - Mariah E Geisen
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY 40202, USA
| | - Alexandra K Sellers
- Department of Bioengineering, University of Louisville, School of Medicine, Louisville, KY 40202, USA
| | - David P Stirling
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Department of Anatomical Sciences and Neurobiology, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Department of Microbiology and Immunology, University of Louisville, School of Medicine, Louisville, KY 40202, USA.
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Mariano V, Domínguez-Iturza N, Neukomm LJ, Bagni C. Maintenance mechanisms of circuit-integrated axons. Curr Opin Neurobiol 2018; 53:162-173. [PMID: 30241058 DOI: 10.1016/j.conb.2018.08.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 08/14/2018] [Indexed: 12/21/2022]
Abstract
Adult, circuit-integrated neurons must be maintained and supported for the life span of their host. The attenuation of either maintenance or plasticity leads to impaired circuit function and ultimately to neurodegenerative disorders. Over the last few years, significant discoveries of molecular mechanisms were made that mediate the formation and maintenance of axons. Here, we highlight intrinsic and extrinsic mechanisms that ensure the health and survival of axons. We also briefly discuss examples of mutations associated with impaired axonal maintenance identified in specific neurological conditions. A better understanding of these mechanisms will therefore help to define targets for therapeutic interventions.
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Affiliation(s)
- Vittoria Mariano
- Department of Fundamental Neurosciences, University of Lausanne, Switzerland; Department of Neurosciences KU Leuven, VIB Center for Brain and Disease Research, Leuven, Belgium
| | - Nuria Domínguez-Iturza
- Department of Fundamental Neurosciences, University of Lausanne, Switzerland; Department of Neurosciences KU Leuven, VIB Center for Brain and Disease Research, Leuven, Belgium
| | - Lukas J Neukomm
- Department of Fundamental Neurosciences, University of Lausanne, Switzerland.
| | - Claudia Bagni
- Department of Fundamental Neurosciences, University of Lausanne, Switzerland; Department of Biomedicine and Prevention, University of Rome Tor Vergata, Italy.
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14
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Definition of Traumatic Brain Injury, Neurosurgery, Trauma Orthopedics, Neuroimaging, Psychology, and Psychiatry in Mild Traumatic Brain Injury. Neuroimaging Clin N Am 2018; 28:1-13. [DOI: 10.1016/j.nic.2017.09.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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15
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Orem BC, Pelisch N, Williams J, Nally JM, Stirling DP. Intracellular calcium release through IP 3 R or RyR contributes to secondary axonal degeneration. Neurobiol Dis 2017; 106:235-243. [DOI: 10.1016/j.nbd.2017.07.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 06/28/2017] [Accepted: 07/10/2017] [Indexed: 11/27/2022] Open
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16
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Pelisch N, Gomes C, Nally JM, Petruska JC, Stirling DP. Differential expression of ryanodine receptor isoforms after spinal cord injury. Neurosci Lett 2017; 660:51-56. [PMID: 28899787 DOI: 10.1016/j.neulet.2017.09.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 09/07/2017] [Accepted: 09/08/2017] [Indexed: 11/24/2022]
Abstract
Ryanodine receptors (RyRs) are highly conductive intracellular Ca2+ release channels and are widely expressed in many tissues, including the central nervous system. RyRs have been implicated in intracellular Ca2+ overload which can drive secondary damage following traumatic injury to the spinal cord (SCI), but the spatiotemporal expression of the three isoforms of RyRs (RyR1-3) after SCI remains unknown. Here, we analyzed the gene and protein expression of RyR isoforms in the murine lumbar dorsal root ganglion (DRG) and the spinal cord lesion site at 1, 2 and 7 d after a mild contusion SCI. Quantitative RT PCR analysis revealed that RyR3 was significantly increased in lumbar DRGs and at the lesion site at 1 and 2 d post contusion compared to sham (laminectomy only) controls. Additionally, RyR2 expression was increased at 1 d post injury within the lesion site. RyR2 and -3 protein expression was localized to lumbar DRG neurons and their spinal projections within the lesion site acutely after SCI. In contrast, RyR1 expression within the DRG and lesion site remained unaltered following trauma. Our study shows that SCI initiates acute differential expression of RyR isoforms in DRG and spinal cord.
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Affiliation(s)
- Nicolas Pelisch
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA; Department of Neurological Surgery, University of Louisville, Louisville, KY, USA
| | - Cynthia Gomes
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA; Department of Neurological Surgery, University of Louisville, Louisville, KY, USA; Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY, USA
| | - Jacqueline M Nally
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA; Department of Neurological Surgery, University of Louisville, Louisville, KY, USA
| | - Jeffrey C Petruska
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA; Department of Neurological Surgery, University of Louisville, Louisville, KY, USA; Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY, USA
| | - David P Stirling
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA; Department of Neurological Surgery, University of Louisville, Louisville, KY, USA; Department of Microbiology and Immunology, University of Louisville, Louisville, KY, USA; Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY, USA.
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Yan J, Zhang L, Agresti MA, Shen F, Matloub HS, Yan Y, Li J, Gu Y, Logiudice JA, Havlik R. Effect of calcitonin on cultured schwann cells. Muscle Nerve 2017; 56:768-772. [DOI: 10.1002/mus.25519] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 12/07/2016] [Accepted: 12/09/2016] [Indexed: 02/01/2023]
Affiliation(s)
- Ji‐Geng Yan
- Department of Plastic SurgeryMedical College of Wisconsin8700 Watertown Plank Road, Milwaukee Wisconsin53226 USA
| | - Lin‐Ling Zhang
- Department of Plastic SurgeryMedical College of Wisconsin8700 Watertown Plank Road, Milwaukee Wisconsin53226 USA
| | - Michael A. Agresti
- Department of Plastic SurgeryMedical College of Wisconsin8700 Watertown Plank Road, Milwaukee Wisconsin53226 USA
| | - Fengyi Shen
- Department of Plastic SurgeryMedical College of Wisconsin8700 Watertown Plank Road, Milwaukee Wisconsin53226 USA
| | - Hani S. Matloub
- Department of Plastic SurgeryMedical College of Wisconsin8700 Watertown Plank Road, Milwaukee Wisconsin53226 USA
| | - Yuhui Yan
- Department of Plastic SurgeryMedical College of Wisconsin8700 Watertown Plank Road, Milwaukee Wisconsin53226 USA
| | - Jifeng Li
- Department of Hand SurgeryHuashan Hospital, Fudan University and Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai Key Laboratory of Peripheral Nerve and MicrosurgeryShanghai China
| | - Yu‐Dong Gu
- Department of Hand SurgeryHuashan Hospital, Fudan University and Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai Key Laboratory of Peripheral Nerve and MicrosurgeryShanghai China
| | - John A. Logiudice
- Department of Plastic SurgeryMedical College of Wisconsin8700 Watertown Plank Road, Milwaukee Wisconsin53226 USA
| | - Robert Havlik
- Department of Plastic SurgeryMedical College of Wisconsin8700 Watertown Plank Road, Milwaukee Wisconsin53226 USA
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Yan Y, Shen FY, Agresti M, Zhang LL, Matloub HS, LoGiudice JA, Havlik R, Li J, Gu YD, Yan JG. Best time window for the use of calcium-modulating agents to improve functional recovery in injured peripheral nerves-An experiment in rats. J Neurosci Res 2017; 95:1786-1795. [PMID: 28052373 DOI: 10.1002/jnr.24009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 11/23/2016] [Accepted: 11/30/2016] [Indexed: 11/08/2022]
Abstract
Peripheral nerve injury can have a devastating effect on daily life. Calcium concentrations in nerve fibers drastically increase after nerve injury, and this activates downstream processes leading to neuron death. Our previous studies showed that calcium-modulating agents decrease calcium accumulation, which aids in regeneration of injured peripheral nerves; however, the optimal therapeutic window for this application has not yet been identified. In this study, we show that calcium clearance after nerve injury is positively correlated with functional recovery in rats suffering from a crushed sciatic nerve injury. After the nerve injury, calcium accumulation increased. Peak volume is from 2 to 8 weeks post injury; calcium accumulation then gradually decreased over the following 24-week period. The compound muscle action potential (CMAP) measurement from the extensor digitorum longus muscle recovered to nearly normal levels in 24 weeks. Simultaneously, real-time polymerase chain reaction results showed that upregulation of calcium-ATPase (a membrane protein that transports calcium out of nerve fibers) mRNA peaked at 12 weeks. These results suggest that without intervention, the peak in calcium-ATPase mRNA expression in the injured nerve occurs after the peak in calcium accumulation, and CMAP recovery continues beyond 24 weeks. Immediately using calcium-modulating agents after crushed nerve injury improved functional recovery. These studies suggest that a crucial time frame in which to initiate effective clinical approaches to accelerate calcium clearance and nerve regeneration would be prior to 2 weeks post injury. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Yuhui Yan
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Feng-Yi Shen
- Froedtert Health-Community Memorial Hospital, Medical College of Wisconsin, Milwaukee
| | - Michael Agresti
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Lin-Ling Zhang
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Hani S Matloub
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - John A LoGiudice
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Robert Havlik
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Jifeng Li
- Department of Hand Surgery, Huashan Hospital, Fudan University and Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Yu-Dong Gu
- Department of Hand Surgery, Huashan Hospital, Fudan University and Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Ji-Geng Yan
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
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19
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Placek LM, Keenan TJ, Wren AW. Bioactivity of Y2O3 and CeO2 doped SiO2-SrO-Na2O glass-ceramics. J Biomater Appl 2016; 31:165-80. [DOI: 10.1177/0885328216651392] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The bioactivity of yttrium and cerium are investigated when substituted for Sodium (Na) in a 0.52SiO2-0.24SrO-0.24 -xNa2O- xMO glass-ceramics (where x = 0.08 and MO = Y2O3 or CeO2). Bioactivity is monitored through pH and inductively coupled plasma-optical emission spectrometry where pH of simulated body fluid ranged from 7.5 to 7.6 and increased between 8.2 and 10.0 after 14-day incubation with the glass-ceramic disks. Calcium (Ca) and phosphorus (P) levels in simulated body fluid after incubation with yttrium and cerium containing disks show a continual decline over the 14-day period. In contrast, Con disks (not containing yttrium or cerium) caused the elimination of Ca in solution after 1 day and throughout the incubation period, and initially showed a decline in P levels followed by an increase at 14 days. Scanning electron microscopy and energy dispersive spectroscopy confirmed the presence of Ca and P on the surface of the simulated body fluid-incubated disks and showed precipitates on Con and HCe (8 mol% cerium) samples. Cell viability of MC3T3 osteoblasts was not significantly affected at a 9% extract concentration. Optical microscopy after 24 h cell incubation with disks showed that Con samples do not support osteoblast or Schwann cell growth, while all yttrium and cerium containing disks have direct contact with osteoblasts spread across the wells. Schwann cells attached in all wells, but only showed spreading with the HY-S (8 mol% yttrium, heated to sintering temperature) and YCe (4 mol% yttrium and cerium) disks. Scanning electron microscopy of the compatible disks shows osteoblast and sNF96.2 Schwann cells attachment and spreading directly on the disk surfaces.
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Affiliation(s)
- LM Placek
- Inamori School of Engineering, Alfred University, Alfred, NY, USA
| | - TJ Keenan
- Inamori School of Engineering, Alfred University, Alfred, NY, USA
| | - AW Wren
- Inamori School of Engineering, Alfred University, Alfred, NY, USA
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Lafrenaye AD, Todani M, Walker SA, Povlishock JT. Microglia processes associate with diffusely injured axons following mild traumatic brain injury in the micro pig. J Neuroinflammation 2015; 12:186. [PMID: 26438203 PMCID: PMC4595283 DOI: 10.1186/s12974-015-0405-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 09/23/2015] [Indexed: 01/08/2023] Open
Abstract
Background Mild traumatic brain injury (mTBI) is an all too common occurrence that exacts significant personal and societal costs. The pathophysiology of mTBI is complex, with reports routinely correlating diffuse axonal injury (DAI) with prolonged morbidity. Progressive chronic neuroinflammation has also recently been correlated to morbidity, however, the potential association between neuroinflammatory microglia and DAI is not well understood. The majority of studies exploring neuroinflammatory responses to TBI have focused on more chronic phases of injury involving phagocytosis associated with Wallerian change. Little, however, is known regarding the neuroinflammatory response seen acutely following diffuse mTBI and its potential relationship to early DAI. Additionally, while inflammation is drastically different in rodents compared to humans, pigs and humans share very similar inflammatory profiles and responses. Methods In the current study, we employed a modified central fluid percussion model in micro pigs. Using this model of diffuse mTBI, paired with various immunohistological endpoints, we assessed the potential association between acute thalamic DAI and neuroinflammation 6 h following injury. Results Injured micro pigs displayed substantial axonal damage reflected in the presence of APP+ proximal axonal swellings, which were particularly prominent in the thalamus. In companion, the same thalamic sites displayed extensive neuroinflammation, which was observed using Iba-1 immunohistochemistry. The physical relationship between microglia and DAI, assessed via confocal 3D analysis, revealed a dramatic increase in the number of Iba-1+ microglial processes that contacted APP+ proximal axonal swellings compared to uninjured myelinated thalamic axons in sham animals. Conclusions In aggregate, these studies reveal acute microglial process convergence on proximal axonal swellings undergoing DAI, an interaction not previously recognized in the literature. These findings transform our understanding of acute neuroinflammation following mTBI and may suggest its potential as a diagnostic and/or a therapeutic target. Electronic supplementary material The online version of this article (doi:10.1186/s12974-015-0405-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Audrey D Lafrenaye
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, P.O. Box 980709, Richmond, VA, 23298, USA.
| | - Masaki Todani
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, P.O. Box 980709, Richmond, VA, 23298, USA. .,Advanced Medical Emergency and Critical Care Center, Yamaguchi University Hospital, Yamaguchi, Japan.
| | - Susan A Walker
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, P.O. Box 980709, Richmond, VA, 23298, USA.
| | - John T Povlishock
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, P.O. Box 980709, Richmond, VA, 23298, USA.
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Beijers AJM, Mols F, Tjan-Heijnen VCG, Faber CG, van de Poll-Franse LV, Vreugdenhil G. Peripheral neuropathy in colorectal cancer survivors: the influence of oxaliplatin administration. Results from the population-based PROFILES registry. Acta Oncol 2015; 54:463-9. [PMID: 25417732 DOI: 10.3109/0284186x.2014.980912] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Chemotherapy-induced peripheral neuropathy (CIPN) is a dose-limiting side effect of oxaliplatin which can negatively influence quality of life. We aimed to study the influence of cumulative dose, dose schedule and dose reductions of adjuvant oxaliplatin on long-term severity and prevalence of CIPN among colorectal cancer (CRC) survivors. MATERIAL AND METHODS In total 207 patients, diagnosed with CRC between 2000 and 2009 who underwent adjuvant treatment with oxaliplatin, were included. They completed the EORTC QLQ-CIPN20 2-11 years after diagnosis. Data on oxaliplatin administration and acute neuropathy during treatment were extracted from the medical files. Subscales were analyzed with analysis of covariance and neuropathy symptoms with logistic regression analysis. RESULTS Patients who received cumulative oxaliplatin dose of ≥ 842 mg/m(2) had a significantly worse EORTC QLQ-CIPN20 sensory score compared to those who received a low cumulative dose of < 421 mg/m(2) (mean 19 vs. 8; p = 0.02). They more often reported tingling toes/feet (13% vs. 2%, respectively; p = 0.01). Dose intensity and time delay did not influence the occurrence of CIPN. Patients receiving a dose reduction because of neuropathy (N = 50) reported a significantly worse sensory score at very similar cumulative doses, than those who did not receive a dose reduction because of neuropathy (N = 96) (mean 21 vs. 15; p = 0.01). CONCLUSION Cumulative dose of oxaliplatin is associated with long-term CIPN. The risk of developing long-term CIPN could only be reduced by decreasing the cumulative dose, whereas delay probably is not beneficial. Patients receiving a dose reduction because of acute neuropathy are still at risk of developing long-term CIPN. Future studies should focus on identifying patients who are at risk of developing CIPN.
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Affiliation(s)
- Antoinetta J M Beijers
- Department of Internal Medicine, Máxima Medical Centre , Eindhoven and Veldhoven , The Netherlands
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Placek LM, Keenan TJ, Laffir F, Coughlan A, Wren AW. Characterization of Y2O3 and CeO2 doped SiO2-SrO-Na2O glasses. BIOMEDICAL GLASSES 2015. [DOI: 10.1515/bglass-2015-0016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThe structural effects of yttrium (Y) and cerium (Ce) are investigated when substituted for sodium (Na) in a 0.52SiO2–0.24SrO–(0.24−x)Na2O–xMO (where x = 0.08; MO = Y2O3 and CeO2) glass series. Network connectivity (NC) was calculated assuming both Y and Ce can act as a network modifier (NC = 2.2) or as a network former (NC up to 2.9). Thermal analysis showed an increase in glass transition temperature (Tg) with increasing Y and Ce content, Y causing the greater increase from the control (Con) at 493∘C to 8 mol% Y (HY) at 660∘C. Vickers hardness (HV) was not significantly different between glasses. 29Si Magic Angle Spinning-Nuclear Magnetic Resonance (MAS-NMR) did not show peak shift with addition of Y, however Ce produced peak broadening and a negative shift in ppm. The addition of 4 mol% Ce in the YCe and LCe glasses shifted the peak from Con at −81.3 ppm to −82.8 ppm and −82.7 ppm respectively; while the HCe glass produced a much broader peak and a shift to −84.8 ppm. High resolution X-ray Photoelectron Spectroscopy for the O 1s spectral line showed the ratio of bridging (BO) to non-bridging oxygens (NBO), BO:NBO,was altered,where Con had a ratio of 0.7, HY decreased to 0.4 and HCe to 0.5.
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Khaitin AM, Rudkovskii MV, Uzdensky AB. The method of isolation of the crayfish abdominal stretch receptor maintaining a connection of the sensory neuron to the ventral nerve cord ganglion. INVERTEBRATE NEUROSCIENCE 2014; 15:176. [DOI: 10.1007/s10158-014-0176-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2014] [Accepted: 10/10/2014] [Indexed: 11/30/2022]
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Calcium release from intra-axonal endoplasmic reticulum leads to axon degeneration through mitochondrial dysfunction. J Neurosci 2014; 34:7179-89. [PMID: 24849352 DOI: 10.1523/jneurosci.4784-13.2014] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Axonal degeneration represents an early pathological event in neurodegeneration, constituting an important target for neuroprotection. Regardless of the initial injury, which could be toxic, mechanical, metabolic, or genetic, degeneration of axons shares a common mechanism involving mitochondrial dysfunction and production of reactive oxygen species. Critical steps in this degenerative process are still unknown. Here we show that calcium release from the axonal endoplasmic reticulum (ER) through ryanodine and IP3 channels activates the mitochondrial permeability transition pore and contributes to axonal degeneration triggered by both mechanical and toxic insults in ex vivo and in vitro mouse and rat model systems. These data reveal a critical and early ER-dependent step during axonal degeneration, providing novel targets for axonal protection in neurodegenerative conditions.
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Histological study on the possible protective action of ginseng on the injurious effect induced by acrylamide on the midbrain in adult male albino rat. ACTA ACUST UNITED AC 2014. [DOI: 10.1097/01.ehx.0000446587.04196.3b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Yan JG, Logiudice J, Davis J, Zhang LL, Agresti M, Sanger J, Matloub HS, Havlik R. Calcitonin pump improves nerve regeneration after transection injury and repair. Muscle Nerve 2014; 51:229-34. [PMID: 24809806 DOI: 10.1002/mus.24281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2014] [Indexed: 11/11/2022]
Abstract
INTRODUCTION After nerve injury, excessive calcium impedes nerve regeneration. We previously showed that calcitonin improved nerve regeneration in crush injury. We aimed to validate the direct effect of calcitonin on transected and repaired nerve. METHODS Two rat groups (n = 8) underwent sciatic nerve transection followed by direct repair. In the calcitonin group, a calcitonin-filled mini-osmotic pump was implanted subcutaneously, with a catheter parallel to the repaired nerve. The control group underwent repair only, without a pump. Evaluation and comparison between the groups included: (1) compound muscle action potential recording of the extensor digitorum longus (EDL) muscle; (2) tetanic muscle force test of EDL; (3) nerve calcium concentration; and (4) nerve fiber count and calcified spot count. RESULTS The calcitonin pump group showed superior recovery. CONCLUSIONS Calcitonin affects injured and repaired peripheral nerve directly. The calcitonin-filled mini-osmotic pump improved nerve functional recovery by accelerating calcium absorption from the repaired nerve. This finding has potential clinical applications.
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Affiliation(s)
- Ji-Geng Yan
- Department of Plastic Surgery, Medical College of Wisconsin, 8700 Watertown Plank Road, Milwaukee, Wisconsin, 53226, USA
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Yang J, Weimer RM, Kallop D, Olsen O, Wu Z, Renier N, Uryu K, Tessier-Lavigne M. Regulation of axon degeneration after injury and in development by the endogenous calpain inhibitor calpastatin. Neuron 2013; 80:1175-89. [PMID: 24210906 DOI: 10.1016/j.neuron.2013.08.034] [Citation(s) in RCA: 151] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/26/2013] [Indexed: 01/30/2023]
Abstract
Axon degeneration is widespread both in neurodegenerative disease and in normal neural development, but the molecular pathways regulating these degenerative processes and the extent to which they are distinct or overlapping remain incompletely understood. We report that calpastatin, an inhibitor of calcium-activated proteases of the calpain family, functions as a key endogenous regulator of axon degeneration. Calpastatin depletion was observed in degenerating axons after physical injury, and maintaining calpastatin inhibited degeneration of transected axons in vitro and in the optic nerve in vivo. Calpastatin depletion also occurred in a caspase-dependent manner in trophic factor-deprived sensory axons and was required for this in vitro model of developmental degeneration. In vivo, calpastatin regulated the normal pruning of retinal ganglion cell axons in their target field. These findings identify calpastatin as a key checkpoint for axonal survival after injury and during development, and demonstrate downstream convergence of these distinct pathways of axon degeneration.
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MESH Headings
- Animals
- Animals, Newborn
- Armadillo Domain Proteins/genetics
- Armadillo Domain Proteins/metabolism
- Axotomy
- Brain/cytology
- Calcium-Binding Proteins/genetics
- Calcium-Binding Proteins/metabolism
- Calpain/metabolism
- Cell Survival/genetics
- Cells, Cultured
- Cytoskeletal Proteins/genetics
- Cytoskeletal Proteins/metabolism
- Disease Models, Animal
- Embryo, Mammalian
- Enzyme Inhibitors/pharmacology
- Ganglia, Spinal/cytology
- Ganglia, Spinal/ultrastructure
- Gene Expression Regulation/physiology
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- HEK293 Cells
- Humans
- In Vitro Techniques
- Mice
- Microscopy, Electron, Transmission
- Nerve Degeneration/etiology
- Nerve Degeneration/metabolism
- Nerve Growth Factor/metabolism
- Nerve Tissue Proteins/metabolism
- Neurons/pathology
- Neurons/ultrastructure
- Nicotinamide-Nucleotide Adenylyltransferase/genetics
- Nicotinamide-Nucleotide Adenylyltransferase/metabolism
- RNA, Messenger/metabolism
- RNA, Small Interfering/metabolism
- Sciatic Neuropathy/complications
- Sciatic Neuropathy/metabolism
- Time Factors
- Transduction, Genetic
- Wallerian Degeneration/pathology
- Wallerian Degeneration/physiopathology
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Affiliation(s)
- Jing Yang
- Laboratory of Brain Development and Repair, The Rockefeller University, New York, NY 10065, USA; Research and Early Development, Genentech Inc., South San Francisco, CA 94080, USA
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28
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New insight in colistin induced neurotoxicity with the mitochondrial dysfunction in mice central nervous tissues. ACTA ACUST UNITED AC 2013; 65:941-8. [DOI: 10.1016/j.etp.2013.01.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 12/20/2012] [Accepted: 01/08/2013] [Indexed: 01/06/2023]
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29
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Axonal degeneration in the peripheral nervous system: Implications for the pathogenesis of amyotrophic lateral sclerosis. Exp Neurol 2013; 246:6-13. [DOI: 10.1016/j.expneurol.2013.05.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 04/22/2013] [Accepted: 05/02/2013] [Indexed: 12/13/2022]
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30
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Öztürk G, Cengiz N, Erdoğan E, Him A, Oğuz EK, Yenidünya E, Ayşit N. Two distinct types of dying back axonal degenerationin vitro. Neuropathol Appl Neurobiol 2013; 39:362-76. [DOI: 10.1111/j.1365-2990.2012.01295.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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31
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Axotomy-induced changes in the chemical coding pattern of colon projecting calbindin-positive neurons in the inferior mesenteric ganglia of the pig. J Mol Neurosci 2013; 51:99-108. [PMID: 23546647 PMCID: PMC3739864 DOI: 10.1007/s12031-013-0007-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 03/18/2013] [Indexed: 02/06/2023]
Abstract
The present study examines the response of colon-projecting neurons localized in the inferior mesenteric ganglia (IMG) to axotomy in the pig animal model. In all animals (n = 8), a median laparotomy was performed under anesthesia and the retrograde tracer Fast Blue was injected into the descending colon wall. In experimental animals (n = 4), the descending colon was exposed and the bilateral caudal colonic nerves were identified and severed. All animals were euthanized and the inferior mesenteric ganglia were harvested and processed for double-labeling immunofluorescence for calbindin-D28k (CB) in combination with either tyrosine hydroxylase (TH), neuropeptide Y (NPY), somatostatin (SOM), vasoactive intestinal polypeptide (VIP), nitric oxide synthase (NOS), Leu-enkephalin (LENK), substance P, vesicular acetylcholine transporter, or galanin. Immunohistochemistry revealed significant changes in the chemical coding pattern of injured inferior mesenteric ganglion neurons. In control animals, Fast Blue-positive neurons were immunoreactive to TH, NPY, SOM, VIP, NOS, LENK, and CB. In the experimental group, the numbers of TH-, NPY-, and SOM-expressing neurons were reduced, whereas the number of neurons immunoreactive to LENK was increased. Our data indicate that the colon-projecting neurons of the porcine IMG react to the axotomy in a similar, but not an identical manner in a comparison to other species, especially rodents. Further studies are needed to elucidate the detailed factors/mechanisms involved in the response to nerve injury.
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32
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Dai C, Zhang D, Li J, Li J. Effect of colistin exposure on calcium homeostasis and mitochondria functions in chick cortex neurons. Toxicol Mech Methods 2013. [DOI: 10.3109/15376516.2012.754533] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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33
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Einheber S, Bhat MA, Salzer JL. Disrupted axo-glial junctions result in accumulation of abnormal mitochondria at nodes of ranvier. ACTA ACUST UNITED AC 2012; 2:165-74. [PMID: 17460780 PMCID: PMC1855224 DOI: 10.1017/s1740925x06000275] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Mitochondria and other membranous organelles are frequently enriched in the nodes and paranodes of peripheral myelinated axons, particularly those of large caliber. The physiologic role(s) of this organelle enrichment and the rheologic factors that regulate it are not well understood. Previous studies suggest that axonal transport of organelles across the nodal/paranodal region is locally regulated. In this study, we have examined the ultrastructure of myelinated axons in the sciatic nerves of mice deficient in the contactin-associated protein (Caspr), an integral junctional component. These mice, which lack the normal septate-like junctions that promote attachment of the glial (paranodal) loops to the axon, contain aberrant mitochondria in their nodal/paranodal regions. These mitochondria are typically large and swollen and occupy prominent varicosities of the nodal axolemma. In contrast, mitochondria located outside the nodal/paranodal regions of the myelinated axons appear normal. These findings suggest that paranodal junctions regulate mitochondrial transport and function in the axoplasm of the nodal/paranodal region of myelinated axons of peripheral nerves. They further implicate the paranodal junctions in playing a role, either directly or indirectly, in the local regulation of energy metabolism in the nodal region.
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Affiliation(s)
- Steven Einheber
- Hunter College School of Health Sciences, 425 E 25th Street, New York, NY 10010, USA.
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34
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Yan JG, Agresti M, Zhang LL, Matloub HS, Sanger JR. Negative Effect of High Calcium Levels on Schwann Cell Survival. NEUROPHYSIOLOGY+ 2012. [DOI: 10.1007/s11062-012-9297-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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35
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Adalbert R, Morreale G, Paizs M, Conforti L, Walker SA, Roderick HL, Bootman MD, Siklós L, Coleman MP. Intra-axonal calcium changes after axotomy in wild-type and slow Wallerian degeneration axons. Neuroscience 2012; 225:44-54. [PMID: 22960623 DOI: 10.1016/j.neuroscience.2012.08.056] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 08/24/2012] [Accepted: 08/26/2012] [Indexed: 10/27/2022]
Abstract
Calcium accumulation induces the breakdown of cytoskeleton and axonal fragmentation in the late stages of Wallerian degeneration. In the early stages there is no evidence for any long-lasting, extensive increase in intra-axonal calcium but there does appear to be some redistribution. We hypothesized that changes in calcium distribution could have an early regulatory role in axonal degeneration in addition to the late executionary role of calcium. Schmidt-Lanterman clefts (SLCs), which allow exchange of metabolites and ions between the periaxonal and extracellular space, are likely to have an increased role when axon segments are separated from the cell body, so we used the oxalate-pyroantimonate method to study calcium at SLCs in distal stumps of transected wild-type and slow Wallerian degeneration (Wld(S)) mutant sciatic nerves, in which Wallerian degeneration is greatly delayed. In wild-type nerves most SLCs show a step gradient of calcium distribution, which is lost at around 20% of SLCs within 3mm of the lesion site by 4-24h after nerve transection. To investigate further the association with Wallerian degeneration, we studied nerves from Wld(S) rats. The step gradient of calcium distribution in Wld(S) is absent in around 20% of the intact nerves beneath SLCs but 4-24h following injury, calcium distribution in transected axons remained similar to that in uninjured nerves. We then used calcium indicators to study influx and buffering of calcium in injured neurites in primary culture. Calcium penetration and the early calcium increase in this system were indistinguishable between Wld(S) and wild-type axons. However, a significant difference was observed during the following hours, when calcium increased in wild-type neurites but not in Wld(S) neurites. We conclude that there is little relationship between calcium distribution and the early stages of Wallerian degeneration at the time points studied in vivo or in vitro but that Wld(S) neurites fail to show a later calcium rise that could be a cause or consequence of the later stages of Wallerian degeneration.
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Affiliation(s)
- R Adalbert
- The Babraham Institute, Babraham Research Campus, Babraham, Cambridge CB22 3AT, United Kingdom.
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36
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Emerick GL, DeOliveira GH, dos Santos AC, Ehrich M. Mechanisms for consideration for intervention in the development of organophosphorus-induced delayed neuropathy. Chem Biol Interact 2012; 199:177-84. [PMID: 22819951 DOI: 10.1016/j.cbi.2012.07.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 07/05/2012] [Accepted: 07/11/2012] [Indexed: 11/15/2022]
Abstract
Organophosphorus-induced delayed neuropathy (OPIDN) is a neurodegenerative disorder characterised by ataxia progressing to paralysis with concomitant central and peripheral distal axonopathy. Symptoms of OPIDN in people include tingling of the hands and feet. This tingling is followed by sensory loss, progressive muscle weakness and flaccidity of the distal skeletal muscles of the lower and upper extremities and ataxia, which appear about 8-14 days after exposure. Some organophosphorus compounds (OPs) that are still used in worldwide agriculture have potential to induce OPIDN, including methamidophos, trichlorfon, dichlorvos and chorpyrifos. This review summarizes experimental attempts to prevent and/or treat OPIDN and the different mechanisms involved in each approach. The initial mechanism associated with development of OPIDN is phosphorylation and inhibition of neuropathy target esterase (NTE). The phosphorylated enzyme undergoes a second reaction known as "aging" that results in the loss of one of the "R" groups bound to the phosphorus of the OP. A second mechanism involved in OPIDN is an imbalance in calcium homeostasis. This can lead to the activation of calcium-activated neutral protease and increases in calcium/calmodulin-dependent protein kinases. These events contribute to aberrant phosphorylation of cytoskeletal proteins and protein digestion in the terminal axon that can proceed similarly to Wallerian-type degeneration. Several experimental studies demonstrated alleviation of the signs and symptoms of OPIDN by restoring calcium balance. Other studies have used preadministration of NTE inhibitors, such as carbamates, thiocarbamates, sulfonyl fluorides and phosphinate to prevent OPIDN. Progress is being made, but there is yet no single specific treatment available for use in clinical practice to prevent or alleviate the severe effects of OPIDN.
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Affiliation(s)
- Guilherme L Emerick
- Department of Natural Active Principles and Toxicology, School of Pharmaceutical Sciences, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil.
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37
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Park SB, Lin CSY, Burke D, Kiernan MC. Activity-dependent conduction failure: molecular insights. J Peripher Nerv Syst 2012; 16:159-68. [PMID: 22003929 DOI: 10.1111/j.1529-8027.2011.00358.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Weakness and fatigue are commonly encountered symptoms in neurological disorders and significantly impair quality of life. In the case of motor axons, conduction block contributes to weakness and fatigue and may be associated with aberrant nerve activity including fasciculations and cramp. These symptoms result from dysfunction of the constituent channels and pumps of the axonal membrane. In critically conducting axons, impulse conduction can be impaired by the effects of activity or by other mechanisms that produce a significant shift in membrane potential. Conduction failure may be accentuated or relieved by maneuvers that manipulate the time course of the driving current, including the administration of agents that interfere with Na(+) channel function. In patients with inflammatory neuropathies, normal activity may be sufficient to precipitate conduction failure at sites of impaired function in multifocal motor neuropathy (MMN) and chronic inflammatory demyelinating polyneuropathy (CIDP). From a clinical perspective, these features are not assessed adequately by conventional neurophysiological techniques. As weakness and fatigue may only develop following activity or exertion, it is useful to assess the effects of impulse trains to determine the extent of conduction failure and the resulting symptoms in neurological patients. These techniques and the physiological mechanisms underlying the development of activity-dependent hyperpolarization will be critically appraised in this review, with a focus on demyelinating neuropathies, MMN and the neurodegenerative disease, and amyotrophic lateral sclerosis (ALS).
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Affiliation(s)
- Susanna B Park
- Prince of Wales Clinical School, University of New South Wales, Sydney, Australia
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38
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Motor nerve terminal destruction and regeneration following anti-ganglioside antibody and complement-mediated injury: An in and ex vivo imaging study in the mouse. Exp Neurol 2012; 233:836-48. [DOI: 10.1016/j.expneurol.2011.12.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 10/27/2011] [Accepted: 12/07/2011] [Indexed: 01/10/2023]
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39
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Clauss RP. Neurotransmitters in disorders of consciousness and brain damage. Med Hypotheses 2011; 77:209-13. [PMID: 21549512 DOI: 10.1016/j.mehy.2011.04.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 03/30/2011] [Accepted: 04/08/2011] [Indexed: 01/17/2023]
Abstract
Restorations from disorders of consciousness such as the minimally conscious state and the vegetative state have been achieved spontaneously or by pharmacological agents such as zolpidem, baclofen, dopaminergic agents and tricyclic antidepressants in some patients. Other restoration methods have included electric and magnetic nerve stimulation, oxygen, Kreb's cycle constituent substitution and axonal re-growth. Although apparently unrelated, these methods all influence neurotransmitter availability or production within the brain. This review proposes depleted neurotransmitter function as a cause for long term brain suppression and disorders of consciousness. It unifies fundamentally different treatment approaches and explores the restoration of neurotransmitter function as a common theme to improve brain function after brain damage.
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Affiliation(s)
- R P Clauss
- Nuclear Medicine Department, Royal Surrey County Hospital, Guildford, Surrey GU27XX, UK.
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40
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Liu WM, Wu JY, Li FC, Chen QX. Ion channel blockers and spinal cord injury. J Neurosci Res 2011; 89:791-801. [PMID: 21394757 DOI: 10.1002/jnr.22602] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 12/11/2010] [Accepted: 12/19/2010] [Indexed: 12/23/2022]
Abstract
The activation of a delayed secondary cascade of unsatisfactory cellular and molecular responses after a primary mechanical insult to the spinal cord causes the progressive degeneration of this structure. Disturbance of ionic homeostasis is part of the secondary injury process and plays an integral role in the early stage of spinal cord injury (SCI). The secondary pathology of SCI is complex and involves disturbance of the homeostasis of K(+) , Na(+) , and Ca(2+) . The effect of ion channel blockers on chronic SCI has also been proved. In this Mini-Review, we provide a comprehensive summary of the effects of ion channel blockers on the natural responses after SCI. Combination therapy is based on the roles of ions and disturbance of their homeostasis in SCI. The effects of ion channel blockers suggest that they have potential in the treatment of SCI, although the complexity of their effects shows that further knowledge is needed before they can be applied clinically.
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Affiliation(s)
- Wang-Mi Liu
- Department of Orthopedic Surgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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41
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Barrientos SA, Martinez NW, Yoo S, Jara JS, Zamorano S, Hetz C, Twiss JL, Alvarez J, Court FA. Axonal degeneration is mediated by the mitochondrial permeability transition pore. J Neurosci 2011; 31:966-78. [PMID: 21248121 PMCID: PMC3245862 DOI: 10.1523/jneurosci.4065-10.2011] [Citation(s) in RCA: 168] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Revised: 10/27/2010] [Accepted: 11/01/2010] [Indexed: 01/23/2023] Open
Abstract
Axonal degeneration is an active process that has been associated with neurodegenerative conditions triggered by mechanical, metabolic, infectious, toxic, hereditary and inflammatory stimuli. This degenerative process can cause permanent loss of function, so it represents a focus for neuroprotective strategies. Several signaling pathways are implicated in axonal degeneration, but identification of an integrative mechanism for this self-destructive process has remained elusive. Here, we show that rapid axonal degeneration triggered by distinct mechanical and toxic insults is dependent on the activation of the mitochondrial permeability transition pore (mPTP). Both pharmacological and genetic targeting of cyclophilin D, a functional component of the mPTP, protects severed axons and vincristine-treated neurons from axonal degeneration in ex vivo and in vitro mouse and rat model systems. These effects were observed in axons from both the peripheral and central nervous system. Our results suggest that the mPTP is a key effector of axonal degeneration, upon which several independent signaling pathways converge. Since axonal and synapse degeneration are increasingly considered early pathological events in neurodegeneration, our work identifies a potential target for therapeutic intervention in a wide variety of conditions that lead to loss of axons and subsequent functional impairment.
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Affiliation(s)
- Sebastian A. Barrientos
- Department of Physiology, Faculty of Biology, Catholic University of Chile, Santiago 8331150, Chile
| | - Nicolas W. Martinez
- Department of Physiology, Faculty of Biology, Catholic University of Chile, Santiago 8331150, Chile
| | - Soonmoon Yoo
- Nemours Biomedical Research Institute, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19716
| | - Juan S. Jara
- Department of Physiology, Faculty of Biology, Catholic University of Chile, Santiago 8331150, Chile
| | - Sebastian Zamorano
- Institute of Biomedical Sciences, Center for Molecular Studies of the Cell and Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago 8380453, Chile
| | - Claudio Hetz
- Institute of Biomedical Sciences, Center for Molecular Studies of the Cell and Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago 8380453, Chile
- Department of Immunology and Infectious Diseases, Harvard University School of Public Health, Boston, Massachusetts 02115
- NeuroUnion Biomedical Foundation, Santiago 7630614, Chile, and
| | - Jeffery L. Twiss
- Department of Biology, Drexel University, Philadelphia, Pennsylvania 19104
| | - Jaime Alvarez
- Department of Physiology, Faculty of Biology, Catholic University of Chile, Santiago 8331150, Chile
| | - Felipe A. Court
- Department of Physiology, Faculty of Biology, Catholic University of Chile, Santiago 8331150, Chile
- NeuroUnion Biomedical Foundation, Santiago 7630614, Chile, and
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42
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RamaRao G, Waghmare CK, Srivastava N, Bhattacharya BK. Regional alterations of JNK3 and CaMKIIα subunit expression in the rat brain after soman poisoning. Hum Exp Toxicol 2010; 30:448-59. [DOI: 10.1177/0960327110386814] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Calcium/calmodulin-dependent protein kinase II (CaMKII) and c-Jun N-terminal kinases (JNKs) exert numerous and diverse functions in the brain. However, their role in nerve agent poisoning is poorly understood. In the present study, rats were exposed to soman (80 µg/kg) subcutaneously to study the changes in the protein levels of calcium/calmodulin-dependent protein kinase II alpha subunit (CaMKIIα) and JNK3 and activities of acetylcholinestarase (AChE) and CaMKII in the rat brain. Western blot analysis revealed that significant changes were found in both the protein kinases expression. Immunoreactivity levels of neural specific JNK3 isoform increased from 2.5 hours to 30 days after soman exposure in cerebral cortex, hippocampus, striatum and thalamus regions and decreased in the case of cerebellum. CaMKIIα expression levels were also increased from 2.5 hours to 30 days after soman exposure in cerebral cortex, hippocampus, thalamus and down regulated in cerebellum. AChE activity remained inhibited in plasma and brain up to 3 days post exposure. CaMKII activity was increased in cerebrum and decreased in cerebellum. Results suggest that altered expression of both the protein kinases play a role in nerve agent-induced long-term neurotoxic effects.
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Affiliation(s)
- G. RamaRao
- Division of Biochemistry, Defense Research and Development Establishment, Gwalior, Madhya Pradesh, India,
| | - CK Waghmare
- Division of Biochemistry, Defense Research and Development Establishment, Gwalior, Madhya Pradesh, India
| | - Nalini Srivastava
- Division of Biochemistry, Defense Research and Development Establishment, Gwalior, Madhya Pradesh, India
| | - BK Bhattacharya
- Division of Biochemistry, Defense Research and Development Establishment, Gwalior, Madhya Pradesh, India
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43
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Xin X, Zeng T, Dou DD, Zhao S, Du JY, Pei JJ, Xie KQ, Zhao XL. Changes of mitochondrial ultrastructures and function in central nervous tissue of hens treated with tri-ortho-cresyl phosphate (TOCP). Hum Exp Toxicol 2010; 30:1062-72. [PMID: 20965953 DOI: 10.1177/0960327110386815] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Tri-ortho-cresyl phosphate (TOCP), an organophosphorus ester, is capable of producing organophosphorus ester-induced delayed neurotoxicity (OPIDN) in humans and sensitive animals. The mechanism of OPIDN has not been fully understood. The present study has been designed to evaluate the role of mitochondrial dysfunctions in the development of OPIDN. Adult hens were treated with 750 mg/kg·bw TOCP by gavage and control hens were given an equivalent volume of corn oil. On day 1, 5, 15, 21 post-dosing, respectively, hens were anesthetized by intraperitoneal injection of sodium pentobarbital and perfused with 4% paraformaldehyde. The cerebral cortex cinerea and the ventral horn of lumbar spinal cord were dissected for electron microscopy. Another batch of hens were randomly divided into three experimental groups and control group. Hens in experimental groups were, respectively, given 185, 375, 750 mg/kg·bw TOCP orally and control group received solvent. After 1, 5, 15, 21 days of administration, they were sacrificed and the cerebrum and spinal cord dissected for the determination of the mitochondrial permeability transition (MPT), membrane potential (Δψ(m)) and the activity of succinate dehydrogenase. Structural changes of mitochondria were observed in hens' nervous tissues, including vacuolation and fission, which increased with time post-dosing. MPT was increased in both the cerebrum and spinal cord, with the most noticeable increase in the spinal cord. Δψ(m) was decreased in both the cerebrum and spinal cord, although there was no significant difference in the three treated groups and control group. The activity of mitochondrial succinate dehydrogenase assayed by methyl thiazolyl tetrazolium (MTT) reduction also confirmed mitochondrial dysfunctions following development of OPIDN. The results suggested mitochondrial dysfunction might partly account for the development of OPIDN induced by TOCP.
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Affiliation(s)
- Xing Xin
- Institute of Toxicology, Shandong University, Shandong, PR China
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44
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Yan JG, Matloub HS, Yan Y, Agresti M, Zhang LL, Jaradeh SS. The correlation between calcium absorption and electrophysiological recovery in crushed rat peripheral nerves. Microsurgery 2010; 30:138-45. [PMID: 19790186 DOI: 10.1002/micr.20709] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The correlation between calcium ion (Ca2+) concentration and electrophysiological recovery in crushed peripheral nerves has not been studied. Observing and quantifying the Ca2+ intensity in live normal and crushed peripheral nerves was performed using a novel microfine tearing technique and Calcium Green-1 Acetoxymethyl ester stain, a fluorescent Ca2+ indicator. Ca2+ was shown to be homogeneously distributed in the myelinated sheaths. After a crush injury, there was significant stasis in the injured zone and the portion distal to the injury. The Ca2+ has been almost completely absorbed after 24 weeks in the injured nerve to be similar to the controls. The process of the calcium absorption was correlated with the Compound Muscle Action Potential recovery process of the injured nerves. This correlation was statistically significant (r = -0.81, P < 0.05). The better understanding of this process will help us to improve nerve regeneration after peripheral nerve injury.
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Affiliation(s)
- Ji-Geng Yan
- Department of Plastic Surgery, Medical College of Wisconsin, Milwaukee, WI, USA.
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45
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Mechanisms of Axonal Spheroid Formation in Central Nervous System Wallerian Degeneration. J Neuropathol Exp Neurol 2010; 69:455-72. [DOI: 10.1097/nen.0b013e3181da84db] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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46
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Mechanisms of axonal injury: internodal nanocomplexes and calcium deregulation. Trends Mol Med 2010; 16:160-70. [PMID: 20207196 DOI: 10.1016/j.molmed.2010.02.002] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 02/01/2010] [Accepted: 02/03/2010] [Indexed: 12/14/2022]
Abstract
Axonal degeneration causes morbidity in many neurological conditions including stroke, neurotrauma and multiple sclerosis. The limited ability of central nervous system (CNS) neurons to regenerate, combined with the observation that axonal damage causes clinical disability, has spurred efforts to investigate the mechanisms of axonal degeneration. Ca influx from outside the axon is a key mediator of injury. More recently, substantial pools of intra-axonal Ca sequestered in the 'axoplasmic reticulum' have been reported. These Ca stores are under the control of multimolecular 'nanocomplexes' located along the internodes under the myelin. The overactivation of these complexes during disease can lead to a lethal release of Ca from intra-axonal stores. Rich receptor pharmacology offers tantalizing therapeutic options targeting these nanocomplexes in the many diseases where axonal degeneration is prominent.
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47
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Shim S, Ming GL. Roles of channels and receptors in the growth cone during PNS axonal regeneration. Exp Neurol 2009; 223:38-44. [PMID: 19833126 DOI: 10.1016/j.expneurol.2009.10.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Revised: 10/01/2009] [Accepted: 10/03/2009] [Indexed: 12/18/2022]
Abstract
Neurons in the peripheral nervous system (PNS) are known to maintain a regenerative capacity and will normally regenerate their axons within a permissive growth environment. The success of regeneration in the PNS largely depends on maintenance of the supportive basal lamina membrane, efficient removal of axonal and myelin debris by macrophages and Schwann cells, expression of neurotrophic factors by Schwann cells, and up-regulation of the intrinsic growth program in PNS neurons. The PNS regenerative process is well characterized through initial Wallerian degeneration followed by axonal sprouting, formation of neuronal growth cones, active axonal growth to the target, and finally sensory and motor functional recovery. The initiation and maintenance of active growth cones during peripheral nerve regeneration recapitulate many aspects of early neural development and are achieved through the activation of complex signaling cascades, involving various receptors, channels, cytoplasmic signaling cascades, as well as transcriptional and translational programs. This review focuses on roles of cell surface ion channels and receptors in the growth cone during Wallerian degeneration and axon regeneration in the PNS.
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Affiliation(s)
- Sangwoo Shim
- Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, BRB 779, Baltimore, MD 21205, USA
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48
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Park SB, Lin CSY, Krishnan AV, Goldstein D, Friedlander ML, Kiernan MC. Oxaliplatin-induced neurotoxicity: changes in axonal excitability precede development of neuropathy. ACTA ACUST UNITED AC 2009; 132:2712-23. [PMID: 19745023 DOI: 10.1093/brain/awp219] [Citation(s) in RCA: 173] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Administration of oxaliplatin, a platinum-based chemotherapy used extensively in the treatment of colorectal cancer, is complicated by prominent dose-limiting neurotoxicity. Acute neurotoxicity develops following oxaliplatin infusion and resolves within days, while chronic neuropathy develops progressively with higher cumulative doses. To investigate the pathophysiology of oxaliplatin-induced neurotoxicity and neuropathy, clinical grading scales, nerve conduction studies and a total of 905 axonal excitability studies were undertaken in a cohort of 58 consecutive oxaliplatin-treated patients. Acutely following individual oxaliplatin infusions, significant changes were evident in both sensory and motor axons in recovery cycle parameters (P < 0.05), consistent with the development of a functional channelopathy of axonal sodium channels. Longitudinally across treatment (cumulative oxaliplatin dose 776 +/- 46 mg/m(2)), progressive abnormalities developed in sensory axons (refractoriness P < or = 0.001; superexcitability P < 0.001; hyperpolarizing threshold electrotonus 90-100 ms P < or = 0.001), while motor axonal excitability remained unchanged (P > 0.05), consistent with the purely sensory symptoms of chronic oxaliplatin-induced neuropathy. Sensory abnormalities occurred prior to significant reduction in compound sensory amplitude and the development of neuropathy (P < 0.01). Sensory excitability abnormalities that developed during early treatment cycles (cumulative dose 294 +/- 16 mg/m(2) oxaliplatin; P < 0.05) were able to predict final clinical outcome on an individual patient basis in 80% of patients. As such, sensory axonal excitability techniques may provide a means to identify pre-clinical oxaliplatin-induced nerve dysfunction prior to the onset of chronic neuropathy. Furthermore, patients with severe neurotoxicity at treatment completion demonstrated greater excitability changes (P < 0.05) than those left with mild or moderate neurotoxicity, suggesting that assessment of sensory excitability parameters may provide a sensitive biomarker of severity for oxaliplatin-induced neurotoxicity.
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Affiliation(s)
- Susanna B Park
- Prince of Wales Medical Research Institute, Barker Street, Randwick, Sydney, NSW 2031, Australia.
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Park SB, Goldstein D, Lin CSY, Krishnan AV, Friedlander ML, Kiernan MC. Acute abnormalities of sensory nerve function associated with oxaliplatin-induced neurotoxicity. J Clin Oncol 2009; 27:1243-9. [PMID: 19164207 DOI: 10.1200/jco.2008.19.3425] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
PURPOSE Neurotoxicity is becoming increasingly recognized as the major dose-limiting toxicity of oxaliplatin. Because the mechanism of oxaliplatin-induced neurotoxicity remains unclear, the present study investigated the potential of axonal excitability techniques in identifying pathophysiologic mechanisms and early markers of nerve dysfunction. PATIENTS AND METHODS Measures of sensory axonal excitability were recorded before and after infusion over 88 treatment cycles in 25 patients with colorectal cancer, who received a total oxaliplatin dose of 766 +/- 56 mg/m(2). Neurologic assessment, clinical rating scales, and routine nerve conduction studies were performed. RESULTS By completion of treatment, 16% of patients had developed severe (grade 3) neurotoxicity, and oxaliplatin dose reduction or cessation as a result of neurotoxicity was required in 40% of patients. Changes in axonal excitability occurred after infusion and could be explained on the basis of alterations in axonal membrane sodium (Na+) channel function (refractoriness: 7.6% +/- 1.7% before infusion v 4.5% +/- 1.4% after infusion; P = .03; superexcitability: -22.8% +/- 0.8% before infusion v -20.1% +/- 1.1% after infusion; P = .0002). Changes became less pronounced in later treatment cycles, suggesting that chronic nerve dysfunction and sensory loss masked acute effects at higher cumulative doses. Importantly, patients who demonstrated reductions in superexcitability in early treatment were subsequently more likely to develop moderate to severe neurotoxicity. The findings suggest that the degree of acute nerve dysfunction may relate to the development of chronic neurotoxicity. CONCLUSION Sensory axonal excitability techniques may facilitate identification of Na+ channel dysfunction in oxaliplatin-induced neurotoxicity and thereby provide a method to identify patients at risk for neurotoxicity to target those most likely to benefit from future neuroprotective strategies.
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Affiliation(s)
- Susanna B Park
- Prince of Wales Medical Research Institute, Barker St, Randwick, Sydney, New South Wales 2031
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Wang QS, Hou LY, Zhang CL, Zhao XL, Yu SF, Xie KQ. 2,5-hexanedione (HD) treatment alters calmodulin, Ca2+/calmodulin-dependent protein kinase II, and protein kinase C in rats' nerve tissues. Toxicol Appl Pharmacol 2008; 232:60-8. [DOI: 10.1016/j.taap.2008.05.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2007] [Revised: 04/30/2008] [Accepted: 05/19/2008] [Indexed: 11/29/2022]
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