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Hannigan IP, Nham B, Wang C, Rosengren SM, Kwok BYC, McGarvie LA, Reid NM, Curthoys IS, Halmágyi GM, Welgampola MS. The Relationship between the Subjective Visual Horizontal and Ocular Vestibular Evoked Myogenic Potentials in Acute Vestibular Neuritis. Otol Neurotol 2023; 44:e419-e427. [PMID: 37254257 DOI: 10.1097/mao.0000000000003909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
OBJECT Vestibular evoked myogenic potentials (VEMPs) and the subjective visual horizontal (SVH) (or vertical [SVV]) have both been considered tests of otolith function: ocular-VEMPs (oVEMPs) utricular function, cervical VEMPs (cVEMPs) saccular function. Some studies have reported association between decreased oVEMPs and SVH, whereas others have not. DESIGN A retrospective study of test results. SETTING A tertiary, neuro-otology clinic, Royal Prince Alfred Hospital, Sydney, Australia. METHOD We analyzed results in 130 patients with acute vestibular neuritis tested within 5 days of onset. We sought correlations between the SVH, oVEMPs, and cVEMPs to air-conducted (AC) and bone-conducted (BC) stimulation. RESULTS The SVH deviated to the side of lesion, in 123 of the 130 AVN patients, by 2.5 to 26.7 degrees. Ninety of the AVN patients (70%) had abnormal oVEMPs to AC, BC or both stimuli, on the AVN side (mean asymmetry ratio ± SD [SE]): (64 ± 45.0% [3.9]). Forty-three of the patients (35%) had impaired cVEMPs to AC, BC or both stimuli, on the AVN side, [22 ± 41.6% (4.1)]. The 90 patients with abnormal oVEMP values also had abnormal SVH. Correlations revealed a significant relationship between SVH offset and oVEMP asymmetry (r = 0.80, p < 0.001) and a weaker relationship between SVH offset and cVEMP asymmetry (r = 0.56, p < 0.001). CONCLUSIONS These results indicate that after an acute unilateral vestibular lesion, before there has been a chance for vestibular compensation to occur, there is a significant correlation between the SVH, and oVEMP results. The relationship between SVH offset and oVEMP amplitude suggests that both tests measure utricular function.
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Affiliation(s)
- Imelda P Hannigan
- Central Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | | | | | | | | | | | - Nicole M Reid
- Neurology Department, Royal Prince Alfred Hospital, Sydney, Australia
| | - Ian S Curthoys
- Vestibular Research Laboratory, School of Psychology, University of Sydney, Sydney, Australia
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Silva Santos Ribeiro P, Willemen HLDM, Eijkelkamp N. Mitochondria and sensory processing in inflammatory and neuropathic pain. FRONTIERS IN PAIN RESEARCH 2022; 3:1013577. [PMID: 36324872 PMCID: PMC9619239 DOI: 10.3389/fpain.2022.1013577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 09/26/2022] [Indexed: 01/24/2023] Open
Abstract
Rheumatic diseases, such as osteoarthritis and rheumatoid arthritis, affect over 750 million people worldwide and contribute to approximately 40% of chronic pain cases. Inflammation and tissue damage contribute to pain in rheumatic diseases, but pain often persists even when inflammation/damage is resolved. Mechanisms that cause this persistent pain are still unclear. Mitochondria are essential for a myriad of cellular processes and regulate neuronal functions. Mitochondrial dysfunction has been implicated in multiple neurological disorders, but its role in sensory processing and pain in rheumatic diseases is relatively unexplored. This review provides a comprehensive understanding of how mitochondrial dysfunction connects inflammation and damage-associated pathways to neuronal sensitization and persistent pain. To provide an overall framework on how mitochondria control pain, we explored recent evidence in inflammatory and neuropathic pain conditions. Mitochondria have intrinsic quality control mechanisms to prevent functional deficits and cellular damage. We will discuss the link between neuronal activity, mitochondrial dysfunction and chronic pain. Lastly, pharmacological strategies aimed at reestablishing mitochondrial functions or boosting mitochondrial dynamics as therapeutic interventions for chronic pain are discussed. The evidence presented in this review shows that mitochondria dysfunction may play a role in rheumatic pain. The dysfunction is not restricted to neuronal cells in the peripheral and central nervous system, but also includes blood cells and cells at the joint level that may affect pain pathways indirectly. Pre-clinical and clinical data suggest that modulation of mitochondrial functions can be used to attenuate or eliminate pain, which could be beneficial for multiple rheumatic diseases.
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Affiliation(s)
| | | | - Niels Eijkelkamp
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
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Cardoso de Oliveira M, Naville Watanabe R, Kohn AF. Electrophysiological and functional signs of Guillain-Barré syndrome predicted by a multiscale neuromuscular computational model. J Neural Eng 2022; 19. [DOI: 10.1088/1741-2552/ac91f8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 09/14/2022] [Indexed: 11/11/2022]
Abstract
Abstract
Objective. The diagnosis of nerve disorders in humans has relied heavily on the measurement of electrical signals from nerves or muscles in response to electrical stimuli applied at appropriate locations on the body surface. The present study investigated the demyelinating subtype of Guillain-Barré syndrome using multiscale computational model simulations to verify how demyelination of peripheral axons may affect plantar flexion torque as well as the ongoing electromyogram (EMG) during voluntary isometric or isotonic contractions. Approach. Changes in axonal conduction velocities, mimicking those found in patients with the disease at different stages, were imposed on a multiscale computational neuromusculoskeletal model to simulate subjects performing unipodal plantar flexion force and position tasks. Main results. The simulated results indicated changes in the torque signal during the early phase of the disease while performing isotonic tasks, as well as in torque variability after partial conduction block while performing both isometric and isotonic tasks. Our results also indicated changes in the root mean square values and in the power spectrum of the soleus EMG signal as well as changes in the synchronisation index computed from the firing times of the active motor units. All these quantitative changes in functional indicators suggest that the adoption of such additional measurements, such as torques and ongoing EMG, could be used with advantage in the diagnosis and be relevant in providing extra information for the neurologist about the level of the disease. Significance. Our findings enrich the knowledge of the possible ways demyelination affects force generation and position control during plantarflexion. Moreover, this work extends computational neuroscience to computational neurology and shows the potential of biologically compatible neuromuscular computational models in providing relevant quantitative signs that may be useful for diagnosis in the clinic, complementing the tools traditionally used in neurological electrodiagnosis.
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English K, Barton MC. HDAC6: A Key Link Between Mitochondria and Development of Peripheral Neuropathy. Front Mol Neurosci 2021; 14:684714. [PMID: 34531721 PMCID: PMC8438325 DOI: 10.3389/fnmol.2021.684714] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 07/30/2021] [Indexed: 01/21/2023] Open
Abstract
Peripheral neuropathy, which is the result of nerve damage from lesions or disease, continues to be a major health concern due to the common manifestation of neuropathic pain. Most investigations into the development of peripheral neuropathy focus on key players such as voltage-gated ion channels or glutamate receptors. However, emerging evidence points to mitochondrial dysfunction as a major player in the development of peripheral neuropathy and resulting neuropathic pain. Mitochondrial dysfunction in neuropathy includes altered mitochondrial transport, mitochondrial metabolism, as well as mitochondrial dynamics. The mechanisms that lead to mitochondrial dysfunction in peripheral neuropathy are poorly understood, however, the Class IIb histone deacetylase (HDAC6), may play an important role in the process. HDAC6 is a key regulator in multiple mechanisms of mitochondrial dynamics and may contribute to mitochondrial dysregulation in peripheral neuropathy. Accumulating evidence shows that HDAC6 inhibition is strongly associated with alleviating peripheral neuropathy and neuropathic pain, as well as mitochondrial dysfunction, in in vivo and in vitro models of peripheral neuropathy. Thus, HDAC6 inhibitors are being investigated as potential therapies for multiple peripheral neuropathic disorders. Here, we review emerging studies and integrate recent advances in understanding the unique connection between peripheral neuropathy and mitochondrial dysfunction through HDAC6-mediated interactions.
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Affiliation(s)
- Krystal English
- UTHealth Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
- UTHealth McGovern Medical School, Houston, TX, United States
| | - Michelle Craig Barton
- UTHealth Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
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Sajic M, Rumora AE, Kanhai AA, Dentoni G, Varatharajah S, Casey C, Brown RDR, Peters F, Hinder LM, Savelieff MG, Feldman EL, Smith KJ. High Dietary Fat Consumption Impairs Axonal Mitochondrial Function In Vivo. J Neurosci 2021; 41:4321-4334. [PMID: 33785643 PMCID: PMC8143198 DOI: 10.1523/jneurosci.1852-20.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [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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Affiliation(s)
- Marija Sajic
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, WC1N 3BG, United Kingdom
| | - Amy E Rumora
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109
| | - Anish A Kanhai
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, WC1N 3BG, United Kingdom
| | - Giacomo Dentoni
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, WC1N 3BG, United Kingdom
| | - Sharlini Varatharajah
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, WC1N 3BG, United Kingdom
| | - Caroline Casey
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, WC1N 3BG, United Kingdom
| | - Ryan D R Brown
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, WC1N 3BG, United Kingdom
| | - Fabian Peters
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, WC1N 3BG, United Kingdom
| | - Lucy M Hinder
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109
| | - Masha G Savelieff
- NeuroNetwork for Emerging Therapies, University of Michigan, Ann Arbor, Michigan 48109
| | - Eva L Feldman
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109
| | - Kenneth J Smith
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, WC1N 3BG, United Kingdom
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Imaging Diagnosis of Central Nervous System Damage in Patients with T2DM. Neurosci Lett 2020; 733:135092. [PMID: 32454146 DOI: 10.1016/j.neulet.2020.135092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/12/2020] [Accepted: 05/21/2020] [Indexed: 11/23/2022]
Abstract
This paper uses resting-state functional magnetic resonance imaging (rs-FMRI) to construct a whole-brain binary functional network through a complex brain network analysis theory based on graph theory to explore the functional network of patients with type 2 diabetes (T2DM). Changes in topological properties and their potential relationships with fasting blood glucose (FBG), glycated haemoglobin (HbAlc), and cognitive function scale, and further explore the diagnostic value of rs-FMRI technology for central nervous system damage in T2DM patients, for clinical diagnosis and treatment Provide objective radiological evidence. In the range of sparsity (Sp) of 0.05 to 0.50 and a step size of 0.01, compared with the random network, the resting brain functional networks in the T2DM group and the HC group have larger clustering coefficients and similar shortest paths. Length and small world index greater than 1, that is, both groups of resting brain functional networks have small world characteristics. The MoCA score of the T2DM group was positively correlated with the node degree (r = 0.400, p = 0.043) and the node efficiency (r = 0.452, p = 0.021) of the right straight back. FBG is positively correlated with the node degree of the left occipital gyrus (r = 0.422, p = 0.023); HbAlc is related to the node degree of the left occipital gyrus (r = 0.372, p = 0.043) and the node degree of the left occipital gyrus (r = 0.382, p = 0.037) was positively correlated with the node intermediary (r = 0.388, p = 0.034) at the back of the right cingulate gyrus. The topological properties of the resting brain function network of T2DM patients with negative MRI findings have changed compared with normal people, indicating that T2DM is an important factor leading to brain function damage, further explaining the rs-fMRI technology and complex brain networks based on graph theory Analysis theory can be used as an effective method to study the changes of brain function in T2DM patients.
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Dai CQ, Guo Y, Chu XY. Neuropathic Pain: the Dysfunction of Drp1, Mitochondria, and ROS Homeostasis. Neurotox Res 2020; 38:553-563. [PMID: 32696439 DOI: 10.1007/s12640-020-00257-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/09/2020] [Accepted: 07/13/2020] [Indexed: 12/17/2022]
Abstract
Neuropathic pain affects the physical and mental health status of patients. Due to its complex pathogenesis and the adverse reactions to medicines, its treatment remains challenging. Among all the etiologies, increasing evidence has pointed to mitochondrial dysfunction. Dynamin-related protein 1 (Drp1)-mediated mitochondrial fragmentation leads to excess ROS generation, which is implicated in the pathogenesis of neuropathic pain. However, the exact mechanism remains unclear. Studies aiming to clarify the possible pathway and relationship between Drp1, mitochondria, ROS, and neuropathic pain may identify a good treatment for neuropathic pain in the clinic. As shown in this review, dysfunction of Drp1 and ROS homeostasis plays essential roles in neuropathic pain. We summarized a Drp1-mitochondrial fission-ROS cycle that potentially functions in neuropathic pain and is regulated by posttranslational modifications and Ca2+. Additionally, we further enumerated six Drp1 inhibitors, including Mdivi-1, P110, Drp1 antisense oligodeoxynucleotides, hyperbaric oxygen, melatonin, and β-hydroxybutyrate, as potential treatments, with the aim of providing guidance for novel molecules to be used in the clinic.
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Affiliation(s)
- Chun-Qiu Dai
- Third Medical District, Lintong Rehabilitation and Convalescent Centre, Xi'an, 710600, People's Republic of China
| | - Yu Guo
- Third Medical District, Lintong Rehabilitation and Convalescent Centre, Xi'an, 710600, People's Republic of China
| | - Xue-Yan Chu
- Third Medical District, Lintong Rehabilitation and Convalescent Centre, Xi'an, 710600, People's Republic of China.
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8
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Muke I, Sprenger A, Bobylev I, Wiemer V, Barham M, Neiss WF, Lehmann HC. Ultrastructural characterization of mitochondrial damage in experimental autoimmune neuritis. J Neuroimmunol 2020; 343:577218. [PMID: 32251941 DOI: 10.1016/j.jneuroim.2020.577218] [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: 03/05/2020] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 12/11/2022]
Abstract
Data are sparse about mitochondrial damage in GBS and in its most frequently employed animal model, experimental autoimmune neuritis (EAN). We here characterized changes in mitochondrial content and morphology at different time points during EAN by use of ultrastructural imaging and immunofluorescent labelling. Histological examination revealed that demyelinated axons and their adjacent Schwann cells showed reduced mitochondrial content and remaining mitochondria appeared swollen with greater diameter in Schwann cells and unmyelinated axons. Our findings indicate that in EAN, particularly mitochondria in Schwann cells are damaged. Further studies are warranted to address whether these changes are amenable to novel, mitoprotective treatments.
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Affiliation(s)
- Ines Muke
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Germany
| | - Alina Sprenger
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Germany
| | - Ilja Bobylev
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Germany
| | - Valerie Wiemer
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, Germany
| | - Mohammed Barham
- Department of Anatomy I, Faculty of Medicine, University of Cologne, Germany
| | | | - Helmar Christoph Lehmann
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Germany.
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Krajnak K. Frequency-dependent changes in mitochondrial number and generation of reactive oxygen species in a rat model of vibration-induced injury. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2020; 83:20-35. [PMID: 31971087 PMCID: PMC7737659 DOI: 10.1080/15287394.2020.1718043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Regular use of vibrating hand tools results in cold-induced vasoconstriction, finger blanching, and a reduction in tactile sensitivity and manual dexterity. Depending upon the length and frequency, vibration induces regeneration, or dysfunction and apoptosis, inflammation and an increase in reactive oxygen species (ROS) levels. These changes may be associated with mitochondria, this study examined the effects of vibration on total and functional mitochondria number. Male rats were exposed to restraint or tail vibration at 62.5, 125, or 250 Hz. The frequency-dependent effects of vibration on mitochondrial number and generation of oxidative stress were examined. After 10 days of exposure at 125 Hz, ventral tail arteries (VTA) were constricted and there was an increase in mitochondrial number and intensity of ROS staining. In the skin, the influence of vibration on arterioles displayed a similar but insignificant response in VTA. There was also a reduction in the number of small nerves with exposure to vibration at 250 Hz, and a reduction in mitochondrial number in nerves in restrained and all vibrated conditions. There was a significant rise in the size of the sensory receptors with vibration at 125 Hz, and an elevation in ROS levels. Based upon these results, mitochondria number and activity are affected by vibration, especially at frequencies at or near resonance. The influence of vibration on the vascular system may either be adaptive or maladaptive. However, the effects on cutaneous nerves might be a precursor to loss of innervation and sensory function noted in workers exposed to vibration.
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Affiliation(s)
- Kristine Krajnak
- Physical Effects Research Branch, National Institute for Occupational Safety and Health, Morgantown, WV, USA
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Andrabi SS, Yang J, Gao Y, Kuang Y, Labhasetwar V. Nanoparticles with antioxidant enzymes protect injured spinal cord from neuronal cell apoptosis by attenuating mitochondrial dysfunction. J Control Release 2019; 317:300-311. [PMID: 31805339 DOI: 10.1016/j.jconrel.2019.12.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 11/26/2019] [Accepted: 12/01/2019] [Indexed: 02/03/2023]
Abstract
In spinal cord injury (SCI), the initial damage leads to a rapidly escalating cascade of degenerative events, known as secondary injury. Loss of mitochondrial homeostasis after SCI, mediated primarily by oxidative stress, is considered to play a crucial role in the proliferation of secondary injury cascade. We hypothesized that effective exogenous delivery of antioxidant enzymes - superoxide dismutase (SOD) and catalase (CAT), encapsulated in biodegradable nanoparticles (nano-SOD/CAT) - at the lesion site would protect mitochondria from oxidative stress, and hence the spinal cord from secondary injury. Previously, in a rat contusion model of severe SCI, we demonstrated extravasation and retention of intravenously administered nanoparticles specifically at the lesion site. To test our hypothesis, a single dose of nano-SOD/CAT in saline was administered intravenously 6 h post-injury, and the spinal cords were analyzed one week post-treatment. Mitochondria isolated from the affected region of the spinal cord of nano-SOD/CAT-treated animals demonstrated significantly reduced mitochondrial reactive oxygen species (ROS) activities, increased mitochondrial membrane potential, reduced calcium levels, and also higher adenosine triphosphate (ATP) production capacity than those isolated from the spinal cords of untreated control or SOD/CAT solution treated animals. Although the treatment did not achieve the same mitochondrial function as in the spinal cords of sham control animals, it significantly attenuated mitochondrial dysfunction following SCI. Further, immunohistochemical analyses of the spinal cords of treated animals showed significantly lower ROS, cleaved caspase-3, and cytochrome c activities, leading to reduced spinal cord neuronal cell apoptosis and smaller lesion area than in untreated animals. These results imply that the treatment significantly attenuated progression of secondary injury that was also reflected from less weight loss and improved locomotive recovery of treated vs. untreated animals. In conclusion, nano-SOD/CAT mitigated activation of cascade of degenerating factors by protecting mitochondria and hence the spinal cord from secondary injury. An effective treatment during the acute phase following SCI could potentially have a positive long-term impact on neurological and functional recovery.
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Affiliation(s)
- Syed Suhail Andrabi
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Jun Yang
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Yue Gao
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Youzhi Kuang
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Vinod Labhasetwar
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
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Roda RH, Hoke A. Mitochondrial dysfunction in HIV-induced peripheral neuropathy. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2019; 145:67-82. [PMID: 31208527 DOI: 10.1016/bs.irn.2019.04.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Mitochondria play an essential role in cellular energy production and calcium homeostasis. Abnormalities in mitochondrial homeostasis and function are seen in several acquired as well as genetic neuropathies, emphasizing their prominent role in neuronal cell activities. Chronic infection with HIV, even when appropriately treated, is a risk factor for developing peripheral neuropathy. In this chapter, we discuss the way in which HIV infection, the resultant toxic viral products that are generated, and some of the viral inhibitors used in its treatment may lead to abnormal mitochondrial function. Of importance are the effects on mitochondrial DNA replication and the neurotoxic effects of the viral gp120 protein. One aspect of mitochondrial dysfunction that remains unexplored is the role of the interaction between mitochondria and the endoplasmic reticulum as a possible target of disruption in HIV neuropathy.
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Affiliation(s)
- Ricardo H Roda
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.
| | - Ahmet Hoke
- Solomon H. Snyder Department of Neuroscience and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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