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Abbaszadeh F, Javadpour P, Mousavi Nasab MM, Jorjani M. The Role of Vitamins in Spinal Cord Injury: Mechanisms and Benefits. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2024; 2024:4293391. [PMID: 38938696 PMCID: PMC11211004 DOI: 10.1155/2024/4293391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 03/18/2024] [Accepted: 06/06/2024] [Indexed: 06/29/2024]
Abstract
Spinal cord injury (SCI) is a common neurological disease worldwide, often resulting in a substantial decrease in quality of life, disability, and in severe cases, even death. Unfortunately, there is currently no effective treatment for this disease. Nevertheless, current basic and clinical evidence suggests that vitamins, with their antioxidant properties and biological functions, may play a valuable role in improving the quality of life for individuals with SCI. They can promote overall health and facilitate the healing process. In this review, we discuss the mechanisms and therapeutic potential of vitamins in the treatment of SCI.
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Affiliation(s)
- Fatemeh Abbaszadeh
- Neurobiology Research CenterShahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Pegah Javadpour
- Neuroscience Research CenterShahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Masoumeh Jorjani
- Neurobiology Research CenterShahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of PharmacologySchool of MedicineShahid Beheshti University of Medical Sciences, Tehran, Iran
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Lee KZ, Vinit S. Modulatory effect of trans-spinal magnetic intermittent theta burst stimulation on diaphragmatic activity following cervical spinal cord contusion in the rat. Spine J 2024; 24:352-372. [PMID: 37774983 DOI: 10.1016/j.spinee.2023.09.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 09/17/2023] [Accepted: 09/18/2023] [Indexed: 10/01/2023]
Abstract
BACKGROUND CONTEXT Magnetic stimulation can noninvasively modulate the neuronal excitability through different stimulatory patterns. PURPOSE The present study hypothesized that trans-spinal magnetic stimulation with intermittent theta burst stimulatory pattern can modulate respiratory motor outputs in a pre-clinical rat model of cervical spinal cord injury. STUDY DESIGN In vivo animal study. METHODS The effect of trans-spinal magnetic intermittent theta burst stimulation on diaphragmatic activity was assessed in adult rats with unilateral cervical spinal cord contusion at 2 weeks postinjury. RESULTS The results demonstrated that unilateral cervical spinal cord contusion significantly attenuated the inspiratory activity and motor evoked potential of the diaphragm. Trans-spinal magnetic intermittent theta burst stimulation significantly increased the inspiratory activity of the diaphragm in cervical spinal cord contused rats. Inspiratory bursting was also recruited by trans-spinal magnetic intermittent theta burst stimulation in the rats without diaphragmatic activity after cervical spinal cord injury. In addition, trans-spinal magnetic intermittent theta burst stimulation is associated with increases in oxygen consumption and carbon dioxide production. CONCLUSIONS These results suggest that trans-spinal magnetic intermittent theta burst stimulation can induce respiratory neuroplasticity. CLINICAL SIGNIFICANCE We propose that trans-spinal theta burst magnetic stimulation may be considered a potential rehabilitative strategy for improving the respiratory activity after cervical spinal cord injury. This will require future clinical study.
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Affiliation(s)
- Kun-Ze Lee
- Department of Biological Sciences, National Sun Yat-sen University, #70 Lien-Hai Rd, Kaohsiung, 804 Taiwan; Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, 9F, First Teaching Building, 100, Shih-Chuan 1st Road, Kaohsiung, 807, Taiwan.
| | - Stéphane Vinit
- END-ICAP, UVSQ, Inserm, Université Paris-Saclay, Versailles 78000, France
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Pan C, Chen Y, Zhou Y. A Fast-Track Respiratory Protocol for High Cervical Spine Injury: A Case Report. J Trauma Nurs 2023; 30:357-363. [PMID: 37937878 PMCID: PMC10681283 DOI: 10.1097/jtn.0000000000000756] [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] [Indexed: 11/09/2023]
Abstract
BACKGROUND Cervical spinal cord injury can greatly affect pulmonary function, resulting in complications, including respiratory failure with prolonged mechanical ventilation, ultimately leading to increased mortality and high health care costs. Weaning from mechanical ventilation is particularly challenging in patients with complete high spinal cord injury. CASE PRESENTATION We present the case of a 42-year-old man who suffered a complete cervical 5-6 spinal cord injury following a rollover motor vehicle crash and subsequently developed postoperative pneumonia and severe hypoxemic respiratory failure. He received a novel approach to fast-track respiratory care, including early and aggressive secretion clearance management, moderate pressure level of airway pressure release ventilation, timely transition to spontaneous mode, early tracheostomy and humane care, and high-flow oxygenation via tracheotomy after weaning off the ventilator. As a result, the patient experienced significant improvement in pulmonary function and was successfully liberated from the ventilator within a 2-week period. CONCLUSION This case highlights the potential effectiveness of fast-track respiratory care in promoting lung function restoration and expediting liberation from mechanical ventilation in patients with severe hypoxemic respiratory failure following a complete cervical spinal cord injury. However, further research is warranted to validate these findings and expand our understanding in this area.
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Affiliation(s)
- Caixue Pan
- Departments of Respiratory Care (Mr Pan and Ms Zhou) and Critical Care Medicine (Dr Chen), West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Yao Chen
- Departments of Respiratory Care (Mr Pan and Ms Zhou) and Critical Care Medicine (Dr Chen), West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Yongfang Zhou
- Departments of Respiratory Care (Mr Pan and Ms Zhou) and Critical Care Medicine (Dr Chen), West China Hospital of Sichuan University, Chengdu, Sichuan, China
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Liberati C, Byrne BJ, Fuller DD, Croft C, Pitts T, Ehrbar J, Leon-Astudillo C, Smith BK. Diaphragm pacing and independent breathing in individuals with severe Pompe disease. FRONTIERS IN REHABILITATION SCIENCES 2023; 4:1184031. [PMID: 37583873 PMCID: PMC10423945 DOI: 10.3389/fresc.2023.1184031] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 07/20/2023] [Indexed: 08/17/2023]
Abstract
Introduction Pompe disease is an inherited disease characterized by a deficit in acid-α-glucosidase (GAA), an enzyme which degrades lysosomal glycogen. The phrenic-diaphragm motor system is affected preferentially, and respiratory failure often occurs despite GAA enzyme replacement therapy. We hypothesized that the continued use of diaphragm pacing (DP) might improve ventilator-dependent subjects' respiratory outcomes and increase ventilator-free time tolerance. Methods Six patients (3 pediatric) underwent clinical DP implantation and started diaphragm conditioning, which involved progressively longer periods of daily, low intensity stimulation. Longitudinal respiratory breathing pattern, diaphragm electromyography, and pulmonary function tests were completed when possible, to assess feasibility of use, as well as diaphragm and ventilatory responses to conditioning. Results All subjects were eventually able to undergo full-time conditioning via DP and increase their maximal tolerated time off-ventilator, when compared to pre-implant function. Over time, 3 of 6 subjects also demonstrated increased or stable minute ventilation throughout the day, without positive-pressure ventilation assistance. Discussion Respiratory insufficiency is one of the main causes of death in patients with Pompe disease. Our results indicate that DP in Pompe disease was feasible, led to few adverse events and stabilized breathing for up to 7 years.
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Affiliation(s)
- Cristina Liberati
- Department of Pediatrics, Boston Children’s Hospital, Boston, MA, United States
| | - Barry J. Byrne
- Department of Pediatrics, University of Florida, Gainesville, FL, United States
| | - David D. Fuller
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States
- Breathing Research and Therapeutics (BREATHE) Center, University of Florida, Gainesville, FL, United States
| | - Chasen Croft
- Department of Surgery, University of Florida, Gainesville, FL, United States
| | - Teresa Pitts
- Department of Speech, Language and Hearing Sciences, University of Missouri, Columbia, MO, United States
- Dalton Cardiovascular Center Investigator, University of Missouri, Columbia, MO, United States
| | - Jessica Ehrbar
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States
| | | | - Barbara K. Smith
- Department of Pediatrics, University of Florida, Gainesville, FL, United States
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States
- Breathing Research and Therapeutics (BREATHE) Center, University of Florida, Gainesville, FL, United States
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Locke KC, Randelman ML, Hoh DJ, Zholudeva LV, Lane MA. Respiratory plasticity following spinal cord injury: perspectives from mouse to man. Neural Regen Res 2022; 17:2141-2148. [PMID: 35259820 PMCID: PMC9083159 DOI: 10.4103/1673-5374.335839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/18/2021] [Accepted: 10/20/2021] [Indexed: 12/03/2022] Open
Abstract
The study of respiratory plasticity in animal models spans decades. At the bench, researchers use an array of techniques aimed at harnessing the power of plasticity within the central nervous system to restore respiration following spinal cord injury. This field of research is highly clinically relevant. People living with cervical spinal cord injury at or above the level of the phrenic motoneuron pool at spinal levels C3-C5 typically have significant impairments in breathing which may require assisted ventilation. Those who are ventilator dependent are at an increased risk of ventilator-associated co-morbidities and have a drastically reduced life expectancy. Pre-clinical research examining respiratory plasticity in animal models has laid the groundwork for clinical trials. Despite how widely researched this injury is in animal models, relatively few treatments have broken through the preclinical barrier. The three goals of this present review are to define plasticity as it pertains to respiratory function post-spinal cord injury, discuss plasticity models of spinal cord injury used in research, and explore the shift from preclinical to clinical research. By investigating current targets of respiratory plasticity research, we hope to illuminate preclinical work that can influence future clinical investigations and the advancement of treatments for spinal cord injury.
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Affiliation(s)
- Katherine C. Locke
- Department of Neurobiology & Anatomy, Drexel University, Philadelphia, PA, USA
- Marion Murray Spinal Cord Research Center, Philadelphia, PA, USA
| | - Margo L. Randelman
- Department of Neurobiology & Anatomy, Drexel University, Philadelphia, PA, USA
- Marion Murray Spinal Cord Research Center, Philadelphia, PA, USA
| | - Daniel J. Hoh
- Lillian S. Wells Department of Neurosurgery, University of Florida, Gainesville, FL, USA
| | - Lyandysha V. Zholudeva
- Marion Murray Spinal Cord Research Center, Philadelphia, PA, USA
- Cardiovascular Disease, Gladstone Institutes, San Francisco, CA, USA
| | - Michael A. Lane
- Department of Neurobiology & Anatomy, Drexel University, Philadelphia, PA, USA
- Marion Murray Spinal Cord Research Center, Philadelphia, PA, USA
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Laliwala A, Daverey A, Agrawal SK, Dash AK. Alpha Tocopherol Loaded Polymeric Nanoparticles: Preparation, Characterizations, and In Vitro Assessments Against Oxidative Stress in Spinal Cord Injury Treatment. AAPS PharmSciTech 2022; 23:195. [PMID: 35831684 DOI: 10.1208/s12249-022-02345-2] [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: 05/14/2022] [Accepted: 06/24/2022] [Indexed: 11/30/2022] Open
Abstract
Spinal cord injury (SCI) is characterized by mechanical injury or trauma to the spinal cord. Currently, SCI treatment requires extremely high doses of neuroprotective agents, which in turn, causes several adverse effects. To overcome these limitations, the present study focuses on delivery of a low but effective dose of a naturally occurring antioxidant, α-tocopherol (α-TP). Calcium alginate nanoparticles (CA-NP) and poly D,L-lactic-co-glycolic acid nanoparticles (PLGA-NP) prepared by ionotropic gelation and solvent evaporation technique had particle size of 21.9 ± 11.19 and 152.4 ± 10.6 nm, respectively. Surface morphology, surface charge, as well as particle size distribution of both nanoparticles were evaluated. Entrapment of α-TP into CA-NP and PLGA-NP quantified by UPLC showed entrapment efficiency of 4.00 ± 1.63% and 76.6 ± 11.4%, respectively. In vitro cytotoxicity profiles on human astrocyte-spinal cord (HA-sp) showed that blank CA-NP at high concentrations reduced the cell viability whereas blank PLGA-NP showed relatively safer cytotoxic profiles. In addition, PLGA nanoparticles encapsulated with α-TP (α-TP-PLGA-NP) in comparison to α-TP alone at high concentrations were less toxic. Pretreatment of HA-sp cells with α-TP-PLGA-NP showed two-fold higher anti-oxidative protection as compared to α-TP alone, when oxidative stress was induced by H2O2. In conclusion, CA-NP were found to be unsuitable for treatment of SCI due to their cytotoxicity. Comparatively, α-TP-PLGA-NP were safer and showed high degree of protection against oxidative stress than α-TP alone.
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Affiliation(s)
- Aayushi Laliwala
- School of Pharmacy and Health Professions, Creighton University, Omaha, Nebraska, 68178, USA
| | - Amita Daverey
- Department of Neurosurgery, University of Nebraska Medical Center, Omaha, Nebraska, 68198, USA
| | - Sandeep K Agrawal
- Department of Neurosurgery, University of Nebraska Medical Center, Omaha, Nebraska, 68198, USA
| | - Alekha K Dash
- School of Pharmacy and Health Professions, Creighton University, Omaha, Nebraska, 68178, USA.
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Palermo AE, Kirk-Sanchez NJ, Garcia KL, Nash MS, Cahalin LP. Inspiratory Muscle Performance Is Related to Seated Balance Function in People With Spinal Cord Injury: An Observational Study. Arch Phys Med Rehabil 2022; 103:1303-1310. [PMID: 34922931 DOI: 10.1016/j.apmr.2021.11.006] [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: 08/27/2021] [Revised: 11/14/2021] [Accepted: 11/16/2021] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To examine the relationship between inspiratory muscle performance (IMP) and functional sitting balance (FSB) in persons with chronic spinal cord injury (SCI). We hypothesized that a moderate correlation would be found between IMP and FSB and that individuals with better balance would have better IMP. DESIGN The SCI-specific modification of the Function in Sitting Test (FIST-SCI) measured FSB. The IMP measures included (1) maximal inspiratory pressure (MIP), (2) sustained MIP (SMIP), and (3) inspiratory duration. Upper extremity motor score (UEMS) and level of injury (LOI) were taken from International Standards for Neurological Classification of Spinal Cord Injury examinations. Spearman correlational analyses assessed relationships among these factors in the sample (N=37). Mann-Whitney U tests explored differences between 2 comparison group pairs (tetraplegia group [TG] vs paraplegia group [PG]; independent transfer group [ITG] vs assisted transfer group [ATG]). Regression analysis examined variables predictive of FSB in the TG. SETTING Research facility. PARTICIPANTS Volunteers with tetraplegia (n=21, American Spinal Injury Association Impairment Scale (AIS) A=8, B=7, C=6) and paraplegia (n=16, AIS A=9, B=4, C=3) (N=37). INTERVENTION Not applicable. MAIN OUTCOME MEASURES IMP, LOI, UEMS, FIST-SCI. RESULTS UEMS, MIP, SMIP, and LOI had moderate to high correlations with FIST-SCI scores (ρ=0.720 (P<.001), 0.480 (P=.003), 0.467 (P=.004), 0.527 (P=.001), respectively). UEMS, MIP, and FIST-SCI scores were higher in the PG and ITG than the TG and ATG, respectively (PG vs. TG P values=<.001, .008, .002, respectively, and ITG vs. ATG P values=<.001, .032, <.001, respectively). Further, SMIP and UEMS predicted FIST-SCI balance scores in the TG, accounting for 55% of total variance (P<.001) (FIST-SCI=11.88+0.03 [SMIP]+0.425 [UEMS]). CONCLUSIONS The relationship between IMP and balance appears preserved after SCI. FSB was predicted, in part, via UEMS and SMIP in the TG. Future research should focus on the effect of SCI-based breathing interventions on FSB.
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Affiliation(s)
- Anne E Palermo
- Department of Physical Therapy, University of Miami Miller School of Medicine, Miami, Florida; Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida.
| | - Neva J Kirk-Sanchez
- Department of Physical Therapy, University of Miami Miller School of Medicine, Miami, Florida
| | - Kelsey L Garcia
- Department of Physical Therapy, University of Miami Miller School of Medicine, Miami, Florida; Department of Rehabilitation, Jackson Health Systems, Miami, Florida
| | - Mark S Nash
- Department of Physical Therapy, University of Miami Miller School of Medicine, Miami, Florida; Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Lawrence P Cahalin
- Department of Physical Therapy, University of Miami Miller School of Medicine, Miami, Florida
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Graham ZA, DeBerry JJ, Cardozo CP, Bamman MM. SS-31 does not prevent or reduce muscle atrophy 7 days after a 65 kdyne contusion spinal cord injury in young male mice. Physiol Rep 2022; 10:e15266. [PMID: 35611788 PMCID: PMC9131615 DOI: 10.14814/phy2.15266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 01/22/2022] [Accepted: 01/25/2022] [Indexed: 05/02/2023] Open
Abstract
Spinal cord injury (SCI) leads to major reductions in function, independent living, and quality of life. Disuse and paralysis from SCI leads to rapid muscle atrophy, with chronic muscle loss likely playing a role in the development of the secondary metabolic disorders often seen in those with SCI. Muscle disuse is associated with mitochondrial dysfunction. Previous evidence has suggested targeting the mitochondria with the tetrapeptide SS-31 is beneficial for muscle health in preclinical models that lead to mitochondrial dysfunction, such as cast immobilization or burn injury. We gave young male mice a sham (n = 8) or 65 kdyne thoracic contusion SCI with (n = 9) or without (n = 9) daily administration of 5.0 mg/kg SS-31. Hindlimb muscle mass and muscle bundle respiration were measured at 7 days post-SCI and molecular targets were investigated using immunoblotting, RT-qPCR, and metabolomics. SS-31 did not preserve body mass or hindlimb muscle mass 7 days post-SCI. SS-31 had no effect on soleus or plantaris muscle bundle respiration. SCI was associated with elevated levels of protein carbonylation, led to reduced protein expression of activated DRP1 and reductions in markers of mitochondrial fusion. SS-31 administration did result in reduced total DRP1 expression, as well as greater expression of inhibited DRP1. Gene expression of proinflammatory cytokines and their receptors were largely stable across groups, although SS-31 treatment led to greater mRNA expression of IL1B, TNF, and TNFRSF12A. In summation, SS-31 was not an efficacious treatment acutely after a moderate thoracic contusion SCI in young male mice.
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Affiliation(s)
- Zachary A. Graham
- Research ServiceBirmingham VA Medical CenterBirminghamAlabamaUSA
- Department of Cell, Developmental, and Integrative BiologyUABBirminghamAlabamaUSA
| | - Jennifer J. DeBerry
- Department of Anesthesiology and Perioperative MedicineUABBirminghamAlabamaUSA
| | - Christopher P. Cardozo
- Center for the Medical Consequences of Spinal Cord InjuryBronxNew YorkUSA
- Medical ServiceJames J. Peters VA Medical CenterBronxNew YorkUSA
- Icahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Marcas M. Bamman
- Research ServiceBirmingham VA Medical CenterBirminghamAlabamaUSA
- Department of Cell, Developmental, and Integrative BiologyUABBirminghamAlabamaUSA
- UAB Center for Exercise MedicineBirminghamAlabamaUSA
- Florida Institute for Human and Machine CognitionPensacolaFloridaUSA
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Chiu TT, Lee KZ. Impact of cervical spinal cord injury on the relationship between the metabolism and ventilation in rats. J Appl Physiol (1985) 2021; 131:1799-1814. [PMID: 34647826 DOI: 10.1152/japplphysiol.00472.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cervical spinal cord injury typically results in respiratory impairments. Clinical and animal studies have demonstrated that respiratory function can spontaneously and partially recover over time after injury. However, it remains unclear whether respiratory recovery is associated with alterations in metabolism. The present study was designed to comprehensively examine ventilation and metabolism in a rat model of spinal cord injury. Adult male rats received sham (i.e., laminectomy) or unilateral mid-cervical contusion injury (height of impact rod: 6.25 or 12.5 mm). Breathing patterns and whole body metabolism (O2 consumption and CO2 production) were measured using a whole body plethysmography system conjugated with flow controllers and gas analyzer at the acute (1 day postinjury), subchronic (2 wk postinjury), and chronic (8 wk postinjury) injury stages. The results demonstrated that mid-cervical contusion caused a significant reduction in the tidal volume. Although the tidal volume of contused animals can gradually recover, it remains lower than that of uninjured animals at the chronic injury stage. Although O2 consumption and CO2 production were similar between uninjured and contused animals at the acute injury stage, these two metabolic parameters were significantly reduced in contused animals at the subchronic to chronic injury stages. Additionally, the relationships between ventilation, metabolism, and body temperature were altered by cervical spinal cord injury. These results suggest that cervical spinal cord injury causes a complicated reconfiguration of ventilation and metabolism that may enable injured animals to maintain a suitable homeostasis for adapting to the pathophysiological consequences of injury.NEW & NOTEWORTHY Ventilation and metabolism are tightly coupled to maintain appropriate energy expenditure under physiological conditions. Our findings demonstrate that cervical spinal cord injury results in the differential reduction of ventilation and metabolism at the various injury stages and leads to alterations in the relationship between ventilation and metabolism. These results from an animal model provide fundamental knowledge for understanding how cervical spinal cord injury impacts energy homeostasis.
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Affiliation(s)
- Tzu-Ting Chiu
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Kun-Ze Lee
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan.,Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
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Inspiratory Muscle Performance and Anthropometric Measures-Novel Assessments Related to Pulmonary Function in People with Spinal Cord Injury: A Pilot Study. Arch Phys Med Rehabil 2021; 103:441-450. [PMID: 34656550 DOI: 10.1016/j.apmr.2021.09.008] [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: 05/10/2021] [Revised: 08/04/2021] [Accepted: 09/09/2021] [Indexed: 11/21/2022]
Abstract
OBJECTIVE To investigate the feasibility and validity of using the novel axillary:umbilical (A:U) ratio and sustained maximal inspiratory pressure (SMIP) as supplementary measures in the assessment of respiratory function in people with spinal cord injury. DESIGN Pilot study with a single day of data collection. All measurements were taken with participants in their personal wheelchairs to best represent normal functioning and positioning for each individual. SETTING Research institution. PARTICIPANTS A convenience sample of 30 community dwelling volunteers with chronic spinal cord injury (C2-T12, American Spinal Injury Association Impairment Scale A-D) participated. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Participants underwent anthropometric measurements (trunk height, abdominal circumference, axillary circumference) and assessment of inspiratory muscle performance, incluidng maximal inspiratory pressure, SMIP, and inspiratory duration, as well as standard pulmonary function tests. RESULTS The A:U ratio and SMIP were recorded for all participants. The SMIP was significantly related to more respiratory performance measures than the maximal inspiratory pressure (P<.05) and the A:U ratio was significantly related to more respiratory performance measures than any other anthropometric measure (P<.05). Additionally, an A:U ratio cutoff point detected individuals with a peak expiratory flow ≥ 80% of their predicted value with a sensitivity and specificity of 85.7% and 91.3%, respectively (area under the curve: 0.92). CONCLUSIONS It is feasible to capture the A:U Ratio and SMIP in individuals with spinal cord injury. Further, the strong significant relationships of SMIP and the A:U ratio to respiratory performance measures suggests their clinical importance in the pulmonary assessment and risk stratification of people with chronic spinal cord injury.
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Randelman M, Zholudeva LV, Vinit S, Lane MA. Respiratory Training and Plasticity After Cervical Spinal Cord Injury. Front Cell Neurosci 2021; 15:700821. [PMID: 34621156 PMCID: PMC8490715 DOI: 10.3389/fncel.2021.700821] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 08/11/2021] [Indexed: 12/30/2022] Open
Abstract
While spinal cord injuries (SCIs) result in a vast array of functional deficits, many of which are life threatening, the majority of SCIs are anatomically incomplete. Spared neural pathways contribute to functional and anatomical neuroplasticity that can occur spontaneously, or can be harnessed using rehabilitative, electrophysiological, or pharmacological strategies. With a focus on respiratory networks that are affected by cervical level SCI, the present review summarizes how non-invasive respiratory treatments can be used to harness this neuroplastic potential and enhance long-term recovery. Specific attention is given to "respiratory training" strategies currently used clinically (e.g., strength training) and those being developed through pre-clinical and early clinical testing [e.g., intermittent chemical stimulation via altering inhaled oxygen (hypoxia) or carbon dioxide stimulation]. Consideration is also given to the effect of training on non-respiratory (e.g., locomotor) networks. This review highlights advances in this area of pre-clinical and translational research, with insight into future directions for enhancing plasticity and improving functional outcomes after SCI.
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Affiliation(s)
- Margo Randelman
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA, United States.,Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Lyandysha V Zholudeva
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA, United States.,Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, United States.,Gladstone Institutes, San Francisco, CA, United States
| | - Stéphane Vinit
- INSERM, END-ICAP, Université Paris-Saclay, UVSQ, Versailles, France
| | - Michael A Lane
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA, United States.,Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, United States
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Cavka K, Fuller DD, Tonuzi G, Fox EJ. Diaphragm Pacing and a Model for Respiratory Rehabilitation After Spinal Cord Injury. J Neurol Phys Ther 2021; 45:235-242. [PMID: 34049339 PMCID: PMC8711094 DOI: 10.1097/npt.0000000000000360] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND AND PURPOSE Cervical spinal cord injury (CSCI) can cause severe respiratory impairment. Although mechanical ventilation (MV) is a lifesaving standard of care for these patients, it is associated with diaphragm atrophy and dysfunction. Diaphragm pacing (DP) is a strategy now used acutely to promote MV weaning and to combat the associated negative effects. Initial reports indicate that DP also may promote neuromuscular plasticity and lead to improvements in spontaneous diaphragm activation and respiratory function. These outcomes suggest the need for reevaluation of respiratory rehabilitation for patients with CSCI using DP and consideration of new rehabilitation models for these patients and their unique care needs. SUMMARY OF KEY POINTS This article discusses the rationale for consideration of DP as a rehabilitative strategy, particularly when used in combination with established respiratory interventions. In addition, a model of respiratory rehabilitation and recovery (RRR) is presented, providing a framework for rehabilitation and consideration of DP as an adjuvant rehabilitation approach. The model promotes goals such as respiratory recovery and independence, and lifelong respiratory health, via interdisciplinary care, respiratory training, quantitative measurement, and use of adjuvant strategies such as DP. Application of the model is demonstrated through a description of an inpatient rehabilitation program that applies model components to patients with CSCI who require DP. RECOMMENDATIONS FOR CLINICAL PRACTICE As DP use increases for patients with acute CSCI, so does the need and opportunity to advance rehabilitation approaches for these patients. This perspective article is a critical step in addressing this need and motivating the advancement of rehabilitation strategies for CSCI patients. (See Video Abstract, Supplemental Digital Content, available at: http://links.lww.com/JNPT/A348).
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Affiliation(s)
- Kathryn Cavka
- Brooks Rehabilitation, Jacksonville, Florida (K.C., G.T., E.J.F.); and Department of Physical Therapy, University of Florida, Gainesville (D.D.F., E.J.F.)
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Gonzalez-Rothi EJ, Lee KZ. Intermittent hypoxia and respiratory recovery in pre-clinical rodent models of incomplete cervical spinal cord injury. Exp Neurol 2021; 342:113751. [PMID: 33974878 DOI: 10.1016/j.expneurol.2021.113751] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 04/24/2021] [Accepted: 05/06/2021] [Indexed: 10/21/2022]
Abstract
Impaired respiratory function is a common and devastating consequence of cervical spinal cord injury. Accordingly, the development of safe and effective treatments to restore breathing function is critical. Acute intermittent hypoxia has emerged as a promising therapeutic strategy to treat respiratory insufficiency in individuals with spinal cord injury. Since the original report by Bach and Mitchell (1996) concerning long-term facilitation of phrenic motor output elicited by brief, episodic exposure to reduced oxygen, a series of studies in animal models have led to the realization that acute intermittent hypoxia may have tremendous potential for inducing neuroplasticity and functional recovery in the injured spinal cord. Advances in our understanding of the neurobiology of acute intermittent hypoxia have prompted us to begin to explore its effects in human clinical studies. Here, we review the basic neurobiology of the control of breathing and the pathophysiology and respiratory consequences of two common experimental models of incomplete cervical spinal cord injury (i.e., high cervical hemisection and mid-cervical contusion). We then discuss the impact of acute intermittent hypoxia on respiratory motor function in these models: work that has laid the foundation for translation of this promising therapeutic strategy to clinical populations. Lastly, we examine the limitations of these animal models and intermittent hypoxia and discuss how future work in animal models may further advance the translation and therapeutic efficacy of this treatment.
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Affiliation(s)
- Elisa J Gonzalez-Rothi
- Breathing Research and Therapeutics Center, Department of Physical Therapy and McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Kun-Ze Lee
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan; Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan.
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Bezdudnaya T, Lane MA, Marchenko V. Pharmacological disinhibition enhances paced breathing following complete spinal cord injury in rats. Respir Physiol Neurobiol 2020; 282:103514. [PMID: 32750492 PMCID: PMC9793860 DOI: 10.1016/j.resp.2020.103514] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/12/2020] [Accepted: 07/29/2020] [Indexed: 12/30/2022]
Abstract
Respiratory dysfunction is one of the most devastating and life-threatening deficits that occurs following cervical spinal cord injury (SCI). Assisted breathing with mechanical ventilators is a necessary part of care for many cervical injured individuals, but it is also associated with increased risk of secondary complications such as infection, muscle atrophy and maladaptive plasticity. Pre-clinical studies with epidural stimulation (EDS) have identified it as an alternative/additional method to support adequate lung ventilation without mechanical assistance. The full potential of EDS, however, may be limited by spinal inhibitory mechanisms within the injured spinal cord. The goal of the present work is to assess the potential improvement for EDS in combination with pharmacological disinhibition of spinal circuits following complete high cervical SCI. All experiments were performed in decerebrate, unanesthetized, non-paralyzed (n = 13) and paralyzed (n = 8) adult Sprague-Dawley rats 6 h following a complete C1 transection. The combination of high-frequency EDS (HF-EDS) at the C4 spinal segment with intrathecal delivery of GABA and glycine receptors antagonists (GABAzine and strychnine, respectively) resulted in significantly increased phrenic motor output, tidal volume and amplitude of diaphragm electrical activity compared to HF-EDS alone. Thus, it appears that spinal fast inhibitory mechanisms limit phrenic motor output and present a new neuropharmacological target to improve paced breathing in individuals with cervical SCI.
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Affiliation(s)
- T Bezdudnaya
- Drexel University College of Medicine, Department of Neurobiology & Anatomy, 2900 W Queen Lane, Philadelphia, PA, 19129, United States
| | - M A Lane
- Drexel University College of Medicine, Department of Neurobiology & Anatomy, 2900 W Queen Lane, Philadelphia, PA, 19129, United States
| | - V Marchenko
- Drexel University College of Medicine, Department of Neurobiology & Anatomy, 2900 W Queen Lane, Philadelphia, PA, 19129, United States; Medical College of Wisconsin, Department of Anesthesiology, 8701 W Watertown Plank Rd, Wauwatosa, WI, 53226, United States.
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15
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Smuder AJ, Turner SM, Schuster CM, Morton AB, Hinkley JM, Fuller DD. Hyperbaric Oxygen Treatment Following Mid-Cervical Spinal Cord Injury Preserves Diaphragm Muscle Function. Int J Mol Sci 2020; 21:ijms21197219. [PMID: 33007822 PMCID: PMC7582297 DOI: 10.3390/ijms21197219] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 09/24/2020] [Accepted: 09/27/2020] [Indexed: 12/17/2022] Open
Abstract
Oxidative damage to the diaphragm as a result of cervical spinal cord injury (SCI) promotes muscle atrophy and weakness. Respiratory insufficiency is the leading cause of morbidity and mortality in cervical spinal cord injury (SCI) patients, emphasizing the need for strategies to maintain diaphragm function. Hyperbaric oxygen (HBO) increases the amount of oxygen dissolved into the blood, elevating the delivery of oxygen to skeletal muscle and reactive oxygen species (ROS) generation. It is proposed that enhanced ROS production due to HBO treatment stimulates adaptations to diaphragm oxidative capacity, resulting in overall reductions in oxidative stress and inflammation. Therefore, we tested the hypothesis that exposure to HBO therapy acutely following SCI would reduce oxidative damage to the diaphragm muscle, preserving muscle fiber size and contractility. Our results demonstrated that lateral contusion injury at C3/4 results in a significant reduction in diaphragm muscle-specific force production and fiber cross-sectional area, which was associated with augmented mitochondrial hydrogen peroxide emission and a reduced mitochondrial respiratory control ratio. In contrast, rats that underwent SCI followed by HBO exposure consisting of 1 h of 100% oxygen at 3 atmospheres absolute (ATA) delivered for 10 consecutive days demonstrated an improvement in diaphragm-specific force production, and an attenuation of fiber atrophy, mitochondrial dysfunction and ROS production. These beneficial adaptations in the diaphragm were related to HBO-induced increases in antioxidant capacity and a reduction in atrogene expression. These findings suggest that HBO therapy may be an effective adjunctive therapy to promote respiratory health following cervical SCI.
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Affiliation(s)
- Ashley J. Smuder
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (A.B.M.); (J.M.H.)
- Breathing Research and Therapeutics, University of Florida, Gainesville, FL 32610, USA;
- Correspondence:
| | - Sara M. Turner
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610, USA; (S.M.T.); (C.M.S.)
| | - Cassandra M. Schuster
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610, USA; (S.M.T.); (C.M.S.)
| | - Aaron B. Morton
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (A.B.M.); (J.M.H.)
| | - J. Matthew Hinkley
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (A.B.M.); (J.M.H.)
| | - David D. Fuller
- Breathing Research and Therapeutics, University of Florida, Gainesville, FL 32610, USA;
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610, USA; (S.M.T.); (C.M.S.)
- McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
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16
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Wollman LB, Streeter KA, Fusco AF, Gonzalez-Rothi EJ, Sandhu MS, Greer JJ, Fuller DD. Ampakines stimulate phrenic motor output after cervical spinal cord injury. Exp Neurol 2020; 334:113465. [PMID: 32949571 DOI: 10.1016/j.expneurol.2020.113465] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 08/31/2020] [Accepted: 09/14/2020] [Indexed: 12/21/2022]
Abstract
Activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors increases phrenic motor output. Ampakines are a class of drugs that are positive allosteric modulators of AMPA receptors. We hypothesized that 1) ampakines can stimulate phrenic activity after incomplete cervical spinal cord injury (SCI), and 2) pairing ampakines with brief hypoxia could enable sustained facilitation of phrenic bursting. Phrenic activity was recorded ipsilateral (IL) and contralateral (CL) to C2 spinal cord hemisection (C2Hx) in anesthetized adult rats. Two weeks after C2Hx, ampakine CX717 (15 mg/kg, i.v.) increased IL (61 ± 46% baseline, BL) and CL burst amplitude (47 ± 26%BL) in 8 of 8 rats. After 90 min, IL and CL bursting remained above baseline (BL) in 7 of 8 rats. Pairing ampakine with a single bout of acute hypoxia (5-min, arterial partial pressure of O2 ~ 50 mmHg) had a variable impact on phrenic bursting, with some rats showing a large facilitation that exceeded the response of the ampakine alone group. At 8 weeks post-C2Hx, 7 of 8 rats increased IL (115 ± 117%BL) and CL burst amplitude (45 ± 27%BL) after ampakine. The IL burst amplitude remained above BL for 90-min in 7 of 8 rats; CL bursting remained elevated in 6 of 8 rats. The sustained impact of ampakine at 8 weeks was not enhanced by hypoxia exposure. Intravenous vehicle (10% 2-Hydroxypropyl-β-cyclodextrin) did not increase phrenic bursting at either time point. We conclude that ampakines effectively stimulate neural drive to the diaphragm after cervical SCI. Pairing ampakines with a single hypoxic exposure did not consistently enhance phrenic motor facilitation.
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Affiliation(s)
- L B Wollman
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610, United States of America; Breathing Research and Therapeutics Center, University of Florida, Gainesville, FL 32610, United States of America
| | - K A Streeter
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610, United States of America; Breathing Research and Therapeutics Center, University of Florida, Gainesville, FL 32610, United States of America
| | - A F Fusco
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610, United States of America
| | - E J Gonzalez-Rothi
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610, United States of America; McKnight Brain Institute, University of Florida, Gainesville, Florida 32610, United States of America; Breathing Research and Therapeutics Center, University of Florida, Gainesville, FL 32610, United States of America
| | - M S Sandhu
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610, United States of America
| | - J J Greer
- Department of Physiology, University of Alberta, Edmonton, AB T6G2SE, Canada
| | - D D Fuller
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610, United States of America; McKnight Brain Institute, University of Florida, Gainesville, Florida 32610, United States of America; Breathing Research and Therapeutics Center, University of Florida, Gainesville, FL 32610, United States of America.
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17
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Upper Cervical Surgery, Increased Signal Intensity of the Spinal Cord, and Hypertension as Risk Factors for Dyspnea After Multilevel Anterior Cervical Discectomy and Fusion. Spine (Phila Pa 1976) 2020; 45:E379-E386. [PMID: 31770331 DOI: 10.1097/brs.0000000000003329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Retrospective study. OBJECTIVE To investigate the associated risk factors for acute respiratory distress after multilevel anterior cervical discectomy and fusion (ACDF) with a focus on the subjective symptom, dyspnea. SUMMARY OF BACKGROUND DATA Acute respiratory distress after ACDF is a relatively common adverse event, the cause of which is usually soft tissue swelling or hematoma. It can result in serious morbidity and requires careful, focused treatment. METHODS We reviewed the records of 532 patients (from January 2014 to August 2018) who had undergone multilevel ACDF surgery. Acute respiratory distress was defined as a complaint of dyspnea within 5 postoperative days. We investigated the patients' demographic parameters, comorbidities, and surgical procedure details. We also investigated radiologic parameters, including magnetic resonance imaging (MRI), with special attention to the prevertebral soft tissue thickness at C3 and C6. Statistical analysis was performed using the Student's t test and multiple logistic regression analysis. RESULTS Out of a total of 484 patients studied after exclusion criteria were applied, 31 patients (6.6%) experienced dyspnea after surgery. We selected 92 patients from the non-dyspnea group and compared them with 31 patients from the dyspnea group. On univariate analysis, upper cervical surgery involving C3, increased cord signal intensity on T2-weighted imaging (T2WI) magnetic resonance imaging (MRI), hypertension, smoking, and prevertebral soft tissue swelling at C3 level on postoperative day 1 were statistically significant factors associated with dyspnea. On logistic regression analysis, upper cervical surgery involving C3, increased cord signal intensity on T2WI MRI, and hypertension were found to be statistically significant variables (P < 0.05). CONCLUSION Patients undergoing upper cervical surgery involving C3, and having increased cord signal intensity on T2WI MRI and hypertension need to be monitored more carefully for acute respiratory distress after multilevel ACDF. LEVEL OF EVIDENCE 4.
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18
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Liu YY, Li LF. Ventilator-induced diaphragm dysfunction in critical illness. Exp Biol Med (Maywood) 2018; 243:1329-1337. [PMID: 30453774 DOI: 10.1177/1535370218811950] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
IMPACT STATEMENT Mechanical ventilation (MV) is life-saving for patients with acute respiratory failure but also causes difficult liberation of patients from ventilator due to rapid decrease of diaphragm muscle endurance and strength, which is termed ventilator-induced diaphragmatic damage (VIDD). Numerous studies have revealed that VIDD could increase extubation failure, ICU stay, ICU mortality, and healthcare expenditures. However, the mechanisms of VIDD, potentially involving a multistep process including muscle atrophy, oxidative loads, structural damage, and muscle fiber remodeling, are not fully elucidated. Further research is necessary to unravel mechanistic framework for understanding the molecular mechanisms underlying VIDD, especially mitochondrial dysfunction and increased mitochondrial oxidative stress, and develop better MV strategies, rehabilitative programs, and pharmacologic agents to translate this knowledge into clinical benefits.
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Affiliation(s)
- Yung-Yang Liu
- 1 Chest Department, Taipei Veterans General Hospital, Taipei 112, Taiwan.,2 Institutes of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei 112, Taiwan
| | - Li-Fu Li
- 3 Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan 333, Taiwan.,4 Department of Respiratory Therapy, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
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19
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Hyatt H, Deminice R, Yoshihara T, Powers SK. Mitochondrial dysfunction induces muscle atrophy during prolonged inactivity: A review of the causes and effects. Arch Biochem Biophys 2018; 662:49-60. [PMID: 30452895 DOI: 10.1016/j.abb.2018.11.005] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Accepted: 11/05/2018] [Indexed: 02/08/2023]
Abstract
Prolonged skeletal muscle inactivity (e.g. limb immobilization, bed rest, mechanical ventilation, spinal cord injury, etc.) results in muscle atrophy that manifests into a decreased quality of life and in select patient populations, a higher risk of morbidity and mortality. Thus, understanding the processes that contribute to muscle atrophy during prolonged periods of muscle disuse is an important area of research. In this regard, mitochondrial dysfunction has been directly linked to the muscle wasting that occurs during extended periods of skeletal muscle inactivity. While the concept that mitochondrial dysfunction contributes to disuse muscle atrophy has been contemplated for nearly 50 years, the mechanisms connecting mitochondrial signaling events to skeletal muscle atrophy remained largely unexplained until recently. Indeed, emerging evidence reveals that mitochondrial dysfunction and the associated mitochondrial signaling events are a requirement for several forms of inactivity-induced skeletal muscle atrophy. Specifically, inactivity-induced alterations in skeletal muscle mitochondria phenotype and increased ROS emission, impaired Ca2+ handling, and release of mitochondria-specific proteolytic activators are established occurrences that promote fiber atrophy during prolonged periods of muscle inactivity. This review highlights the evidence that directly connects mitochondrial dysfunction and aberrant mitochondrial signaling with skeletal muscle atrophy and discusses the mechanisms linking these interconnected phenomena.
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Affiliation(s)
- Hayden Hyatt
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA.
| | - Rafael Deminice
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA; Department of Physical Education, University of Estadual of Londrina, Londrina, Brazil
| | - Toshinori Yoshihara
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA; Department of Exercise Physiology, Juntendo University, Tokyo, Japan
| | - Scott K Powers
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
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20
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Endurance exercise protects skeletal muscle against both doxorubicin-induced and inactivity-induced muscle wasting. Pflugers Arch 2018; 471:441-453. [PMID: 30426248 DOI: 10.1007/s00424-018-2227-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 10/09/2018] [Accepted: 10/18/2018] [Indexed: 12/20/2022]
Abstract
Repeated bouts of endurance exercise promotes numerous biochemical adaptations in skeletal muscle fibers resulting in a muscle phenotype that is protected against a variety of homeostatic challenges; these exercise-induced changes in muscle phenotype are often referred to as "exercise preconditioning." Importantly, exercise preconditioning provides protection against several threats to skeletal muscle health including cancer chemotherapy (e.g., doxorubicin) and prolonged muscle inactivity. This review summarizes our current understanding of the mechanisms responsible for exercise-induced protection of skeletal muscle fibers against both doxorubicin-induced muscle wasting and a unique form of inactivity-induced muscle atrophy (i.e., ventilator-induced diaphragm atrophy). Specifically, the first section of this article will highlight the potential mechanisms responsible for exercise-induced protection of skeletal muscle fibers against doxorubicin-induced fiber atrophy. The second segment will discuss the biochemical changes that are responsible for endurance exercise-mediated protection of diaphragm muscle against ventilator-induced diaphragm wasting. In each section, we highlight gaps in our knowledge in hopes of stimulating future research in this evolving field of investigation.
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21
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Warren PM, Campanaro C, Jacono FJ, Alilain WJ. Mid-cervical spinal cord contusion causes robust deficits in respiratory parameters and pattern variability. Exp Neurol 2018; 306:122-131. [PMID: 29653187 PMCID: PMC6333202 DOI: 10.1016/j.expneurol.2018.04.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 03/24/2018] [Accepted: 04/06/2018] [Indexed: 02/08/2023]
Abstract
Mid-cervical spinal cord contusion disrupts both the pathways and motoneurons vital to the activity of inspiratory muscles. The present study was designed to determine if a rat contusion model could result in a measurable deficit to both ventilatory and respiratory motor function under “normal” breathing conditions at acute to chronic stages post trauma. Through whole body plethysmography and electromyography we assessed respiratory output from three days to twelve weeks after a cervical level 3 (C3) contusion. Contused animals showed significant deficits in both tidal and minute volumes which were sustained from acute to chronic time points. We also examined the degree to which the contusion injury impacted ventilatory pattern variability through assessment of Mutual Information and Sample Entropy. Mid-cervical contusion significantly and robustly decreased the variability of ventilatory patterns. The enduring deficit to the respiratory motor system caused by contusion was further confirmed through electromyography recordings in multiple respiratory muscles. When isolated via a lesion, these contused pathways were insufficient to maintain respiratory activity at all time points post injury. Collectively these data illustrate that, counter to the prevailing literature, a profound and lasting ventilatory and respiratory motor deficit may be modelled and measured through multiple physiological assessments at all time points after cervical contusion injury.
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Affiliation(s)
- Philippa M Warren
- Department of Neurosciences, MetroHealth Medical Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA; School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Cara Campanaro
- Division of Pulmonary Critical Care and Sleep Medicine and Louis Stokes VA Medical Center, Department of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Frank J Jacono
- Division of Pulmonary Critical Care and Sleep Medicine and Louis Stokes VA Medical Center, Department of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Warren J Alilain
- Department of Neurosciences, MetroHealth Medical Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Spinal Cord and Brain Injury Research Centre, University of Kentucky, Lexington, KY 40536, USA.
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22
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Smuder AJ, Sollanek KJ, Nelson WB, Min K, Talbert EE, Kavazis AN, Hudson MB, Sandri M, Szeto HH, Powers SK. Crosstalk between autophagy and oxidative stress regulates proteolysis in the diaphragm during mechanical ventilation. Free Radic Biol Med 2018; 115:179-190. [PMID: 29197632 PMCID: PMC5767544 DOI: 10.1016/j.freeradbiomed.2017.11.025] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 11/27/2017] [Accepted: 11/28/2017] [Indexed: 12/25/2022]
Abstract
Mechanical ventilation (MV) results in the rapid development of ventilator-induced diaphragm dysfunction (VIDD). While the mechanisms responsible for VIDD are not fully understood, recent data reveal that prolonged MV activates autophagy in the diaphragm, which may occur as a result of increased cellular reactive oxygen species (ROS) production. Therefore, we tested the hypothesis that (1) accelerated autophagy is a key contributor to VIDD; and that (2) oxidative stress is required to increase the expression of autophagy genes in the diaphragm. Our findings reveal that targeted inhibition of autophagy in the rat diaphragm prevented MV-induced muscle atrophy and contractile dysfunction. Attenuation of VIDD in these animals occurred as a result of increased diaphragm concentration of the antioxidant catalase and reduced mitochondrial ROS emission, which corresponded to reductions in the activity of calpain and caspase-3. To determine if increased ROS production is required for the upregulation of autophagy biomarkers in the diaphragm, rats that were administered the mitochondrial-targeted peptide SS-31 during MV. Results from this study demonstrated that mitochondrial ROS production in the diaphragm during MV is required for the increased expression of key autophagy genes (i.e. LC3, Atg7, Atg12, Beclin1 and p62), as well as for increased activity of cathepsin L. Together, these data reveal that autophagy is required for VIDD, and that autophagy inhibition reduces MV-induced diaphragm ROS production and prevents a positive feedback loop whereby increased autophagy is stimulated by oxidative stress, resulting in further increases in ROS and autophagy.
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Affiliation(s)
- Ashley J Smuder
- Department of Exercise Science, University of South Carolina, Room 227, 921 Assembly St, Columbia, SC 29208, United States.
| | - Kurt J Sollanek
- Department of Kinesiology, Sonoma State University, Rohnert Park, CA 94928, United States
| | - W Bradley Nelson
- Department of Natural Sciences, Ohio Dominican University, Columbus, OH 43219, United States
| | - Kisuk Min
- Department of Pharmacology, Yale University, New Haven, CT 06520, United States
| | - Erin E Talbert
- Department of Molecular Virology, Immunology and Medical Genetics, Ohio State University, Columbus, OH 43210, United States
| | - Andreas N Kavazis
- School of Kinesiology, Auburn University, Auburn, AL 36849, United States
| | - Matthew B Hudson
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE 19716, United States
| | - Marco Sandri
- Department of Biomedical Science, University of Padova, Padova, Italy
| | - Hazel H Szeto
- Department of Pharmacology, Weill Cornell Medical College, New York, NY 10021, United States
| | - Scott K Powers
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, United States
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23
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Sunshine MD, Ganji CN, Reier PJ, Fuller DD, Moritz CT. Intraspinal microstimulation for respiratory muscle activation. Exp Neurol 2018; 302:93-103. [PMID: 29305050 DOI: 10.1016/j.expneurol.2017.12.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 12/20/2017] [Accepted: 12/26/2017] [Indexed: 11/17/2022]
Abstract
A complex propriospinal network is synaptically coupled to phrenic and intercostal motoneurons, and this makes it difficult to predict how gray matter intraspinal microstimulation (ISMS) will recruit respiratory motor units. We therefore mapped the cervical and high thoracic gray matter at locations which ISMS activates diaphragm (DIA) and external intercostal (EIC) motor units. Respiratory muscle electromyography (EMG) was recorded in anesthetized female spinally intact adult rats while a stimulating electrode was advanced ventrally into the spinal cord in 600μm increments. At each depth, single biphasic stimuli were delivered at 10-90μA during both the inspiratory and expiratory phase independently. Twenty electrode tracks were made from C2-T1 at medial and lateral gray matter locations. During inspiration, ISMS evoked DIA and EIC activity throughout C2-T1 gray matter locations, with mutual activation occurring at 17±9% of sites. During inspiratory phase ISMS the average latency for DIA activation was 4.40±0.70ms. During the expiratory phase, ISMS-induced DIA activation required electrodes to be in close proximity to the phrenic motoneuron pool, and average activation latency was 3.30±0.50ms. We conclude that appropriately targeted ISMS can co-activate DIA and EIC motor units, and endogenous respiratory drive has a powerful impact on ISMS-induced respiratory motor unit activation. The long latency diaphragm motor unit activation suggests the presence of a complex propriospinal network that can modulate phrenic motor output.
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Affiliation(s)
- Michael D Sunshine
- Rehabilitation Medicine, University of Washington, Seattle, WA, United States; Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, United States; Physical Therapy and McKnight Brain Institute, University of Florida, Gainesville, FL, United States.
| | - Comron N Ganji
- Rehabilitation Medicine, University of Washington, Seattle, WA, United States; Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, United States
| | - Paul J Reier
- Neuroscience, University of Florida, Gainesville, FL, United States
| | - David D Fuller
- Physical Therapy and McKnight Brain Institute, University of Florida, Gainesville, FL, United States; Center for Respiratory Research and Rehabilitation, University of Florida, Gainesville, FL, United States
| | - Chet T Moritz
- Rehabilitation Medicine, University of Washington, Seattle, WA, United States; Center for Sensorimotor Neural Engineering (CSNE), Seattle, WA, United States; Physiology & Biophysics, University of Washington, Seattle, WA, United States; University of Washington Institute for Neuroengineering (UWIN), University of Washington, Seattle, WA, United States
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24
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Lin CC, Lai SR, Shao YH, Chen CL, Lee KZ. The Therapeutic Effectiveness of Delayed Fetal Spinal Cord Tissue Transplantation on Respiratory Function Following Mid-Cervical Spinal Cord Injury. Neurotherapeutics 2017; 14:792-809. [PMID: 28097486 PMCID: PMC5509620 DOI: 10.1007/s13311-016-0509-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Respiratory impairment due to damage of the spinal respiratory motoneurons and interruption of the descending drives from brainstem premotor neurons to spinal respiratory motoneurons is the leading cause of morbidity and mortality following cervical spinal cord injury. The present study was designed to evaluate the therapeutic effectiveness of delayed transplantation of fetal spinal cord (FSC) tissue on respiratory function in rats with mid-cervical spinal cord injury. Embryonic day-14 rat FSC tissue was transplanted into a C4 spinal cord hemilesion cavity in adult male rats at 1 week postinjury. The histological results showed that FSC-derived grafts can survive, fill the lesion cavity, and differentiate into neurons and astrocytes at 8 weeks post-transplantation. Some FSC-derived graft neurons exhibited specific neurochemical markers of neurotransmitter (e.g., serotonin, noradrenalin, or acetylcholine). Moreover, a robust expression of glutamatergic and γ-aminobutyric acid-ergic fibers was observed within FSC-derived grafts. Retrograde tracing results indicated that there was a connection between FSC-derived grafts and host phrenic nucleus. Neurophysiological recording of the phrenic nerve demonstrated that phrenic burst amplitude ipsilateral to the lesion was significantly greater in injured animals that received FSC transplantation than in those that received buffer transplantation under high respiratory drives. These results suggest that delayed FSC transplantation may have the potential to repair the injured spinal cord and promote respiratory functional recovery after mid-cervical spinal cord injury.
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Affiliation(s)
- Chia-Ching Lin
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Sih-Rong Lai
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Yu-Han Shao
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Chun-Lin Chen
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University and Academia Sinica, Kaohsiung, Taiwan
| | - Kun-Ze Lee
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan.
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University and Academia Sinica, Kaohsiung, Taiwan.
- Center for Neuroscience, National Sun Yat-sen University, Kaohsiung, Taiwan.
- Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung, Taiwan.
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan.
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25
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Powers SK. Exercise: Teaching myocytes new tricks. J Appl Physiol (1985) 2017; 123:460-472. [PMID: 28572498 DOI: 10.1152/japplphysiol.00418.2017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 05/26/2017] [Accepted: 05/28/2017] [Indexed: 12/31/2022] Open
Abstract
Endurance exercise training promotes numerous cellular adaptations in both cardiac myocytes and skeletal muscle fibers. For example, exercise training fosters changes in mitochondrial function due to increased mitochondrial protein expression and accelerated mitochondrial turnover. Additionally, endurance exercise training alters the abundance of numerous cytosolic and mitochondrial proteins in both cardiac and skeletal muscle myocytes, resulting in a protective phenotype in the active fibers; this exercise-induced protection of cardiac and skeletal muscle fibers is often referred to as "exercise preconditioning." As few as 3-5 consecutive days of endurance exercise training result in a preconditioned cardiac phenotype that is sheltered against ischemia-reperfusion-induced injury. Similarly, endurance exercise training results in preconditioned skeletal muscle fibers that are resistant to a variety of stresses (e.g., heat stress, exercise-induced oxidative stress, and inactivity-induced atrophy). Many studies have probed the mechanisms responsible for exercise-induced preconditioning of cardiac and skeletal muscle fibers; these studies are important, because they provide an improved understanding of the biochemical mechanisms responsible for exercise-induced preconditioning, which has the potential to lead to innovative pharmacological therapies aimed at minimizing stress-induced injury to cardiac and skeletal muscle. This review summarizes the development of exercise-induced protection of cardiac myocytes and skeletal muscle fibers and highlights the putative mechanisms responsible for exercise-induced protection in the heart and skeletal muscles.
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Affiliation(s)
- Scott K Powers
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
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26
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Vagal Control of Breathing Pattern after Midcervical Contusion in Rats. J Neurotrauma 2017; 34:734-745. [DOI: 10.1089/neu.2016.4645] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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Lee KZ, Chiang SC, Li YJ. Mild Acute Intermittent Hypoxia Improves Respiratory Function in Unanesthetized Rats With Midcervical Contusion. Neurorehabil Neural Repair 2016; 31:364-375. [DOI: 10.1177/1545968316680494] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Background. Mild intermittent hypoxia has been considered a potential approach to induce respiratory neuroplasticity. Objective. The purpose of the present study was to investigate whether mild acute intermittent hypoxia can improve breathing function in a clinically relevant spinal cord injury animal model. Methods. Adult male rats received laminectomy or unilateral contusion at the C3-C4 spinal cord using a MASCIS Impactor (height: 6.25 or 12.5 mm). At 4 weeks postinjury, the breathing patterns of unanesthetized rats were measured by whole body plethysmography before, during and after 10 episodes of 5 minutes of hypoxia (10% O2, 4% CO2, balance N2) with 5 minutes of normoxia intervals. Results. The results demonstrated that cervical contusion resulted in reduction in breathing capacity and number of phrenic motoneurons. Acute hypoxia induced significant increases in frequency and tidal volume in sham surgery and contused animals. In addition, there was a progressive decline in the magnitude of hypoxic ventilatory response during intermittent hypoxia. Further, the tidal volume was significantly enhanced in contused but not sham surgery rats at 15 and 30 minutes postintermittent hypoxia, suggesting intermittent hypoxia can bring about long-term facilitation of tidal volume following cervical spinal contusion. Conclusions. These results suggest that mild acute intermittent hypoxia can elicit differential forms of respiratory plasticity in sham surgery versus contused animals, and may be a promising neurorehabilitation approach to improve respiratory function after cervical spinal cord injury.
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Affiliation(s)
- Kun-Ze Lee
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
- Center for Neuroscience, National Sun Yat-sen University, Kaohsiung, Taiwan
- Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung, Taiwan
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University and Academia Sinica, Taiwan
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Shu-Chi Chiang
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Yu-Jie Li
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
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28
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Mercier LM, Gonzalez-Rothi EJ, Streeter KA, Posgai SS, Poirier AS, Fuller DD, Reier PJ, Baekey DM. Intraspinal microstimulation and diaphragm activation after cervical spinal cord injury. J Neurophysiol 2016; 117:767-776. [PMID: 27881723 DOI: 10.1152/jn.00721.2016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 11/21/2016] [Indexed: 12/15/2022] Open
Abstract
Intraspinal microstimulation (ISMS) using implanted electrodes can evoke locomotor movements after spinal cord injury (SCI) but has not been explored in the context of respiratory motor output. An advantage over epidural and direct muscle stimulation is the potential of ISMS to selectively stimulate components of the spinal respiratory network. The present study tested the hypothesis that medullary respiratory activity could be used to trigger midcervical ISMS and diaphragm motor unit activation in rats with cervical SCI. Studies were conducted after acute (hours) and subacute (5-21 days) C2 hemisection (C2Hx) injury in adult rats. Inspiratory bursting in the genioglossus (tongue) muscle was used to trigger a 250-ms train stimulus (100 Hz, 100-200 μA) to the ventral C4 spinal cord, targeting the phrenic motor nucleus. After both acute and subacute injury, genioglossus EMG activity effectively triggered ISMS and activated diaphragm motor units during the inspiratory phase. The ISMS paradigm also evoked short-term potentiation of spontaneous inspiratory activity in the previously paralyzed hemidiaphragm (i.e., bursting persisting beyond the stimulus period) in ∼70% of the C2Hx animals. We conclude that medullary inspiratory output can be used to trigger cervical ISMS and diaphragm activity after SCI. Further refinement of this method may enable "closed-loop-like" ISMS approaches to sustain ventilation after severe SCI.NEW & NOTEWORTHY We examined the feasibility of using intraspinal microstimulation (ISMS) of the cervical spinal cord to evoke diaphragm activity ipsilateral to acute and subacute hemisection of the upper cervical spinal cord of the rat. This proof-of-concept study demonstrated the efficacy of diaphragm activation, using an upper airway respiratory EMG signal to trigger ISMS at the level of the ipsilesional phrenic nucleus during acute and advanced postinjury intervals.
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Affiliation(s)
- L M Mercier
- Department of Neuroscience, University of Florida, Gainesville, Florida
| | - E J Gonzalez-Rothi
- Department of Physical Therapy, University of Florida, Gainesville, Florida; and
| | - K A Streeter
- Department of Physical Therapy, University of Florida, Gainesville, Florida; and
| | - S S Posgai
- Department of Neuroscience, University of Florida, Gainesville, Florida
| | - A S Poirier
- Department of Physical Therapy, University of Florida, Gainesville, Florida; and
| | - D D Fuller
- Department of Physical Therapy, University of Florida, Gainesville, Florida; and
| | - P J Reier
- Department of Neuroscience, University of Florida, Gainesville, Florida
| | - D M Baekey
- Department of Physiological Sciences, University of Florida, Gainesville, Florida
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Wang K, Wang WT, Wang J, Chen Z, Song QX, Chen SY, Hao Q, He DW, Shen HX. Compared study of routine magnetic resonance imaging and diffusion tensor tractography on the predictive value of diagnosis and prognosis in acute cervical spinal cord injury. JOURNAL OF ACUTE DISEASE 2016. [DOI: 10.1016/j.joad.2016.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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