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Clark JM, Bednarz JM, Batchelor PE, Skeers P, Freeman BJC. Prehospital Cardiovascular Autoregulatory Disturbances Correlate With the Functional Neuroanatomy of Acute Spinal Cord Injury. Spine (Phila Pa 1976) 2023; 48:428-435. [PMID: 36577080 DOI: 10.1097/brs.0000000000004571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/19/2022] [Indexed: 12/30/2022]
Abstract
STUDY DESIGN Retrospective study. OBJECTIVE The importance of attenuating the cardiovascular autoregulatory disturbances accompanying acute spinal cord injury (SCI) has long been recognized. This report assembles SCI emergency service data and correlates cardiovascular parameters to preserved functional neuroanatomy. SUMMARY OF BACKGROUND DATA The nascent nature of evidence-based reporting of prehospital cardiovascular autoregulatory disturbances in SCI indicates the need to assemble more information. MATERIALS AND METHODS SCI data for <24 hours were extracted from ambulance and hospital records. The mean arterial pressure (MAP) was calculated. The International Standard for Neurological Classification of SCI (ISNCSCI) evaluates the primary outcome of motor incomplete injury (grades C/D) at acute presentation. Logistic regression was adjusted for multiple confounders that were expected to influence the odds of grade C/D. RESULTS A cohort of 99 acute SCI cases was retained; mean (SD) age 40.7±20.5 years, 88 male, 84 tetraplegic, 65 grades A/B (motor complete injury), triage time 2±1.6 hours. The lowest recorded prehospital MAP [mean (SD): 77.9±19, range: 45-145 mm Hg] approached the nadir for adequate organ perfusion. Thirty-four (52%) grade A/B and 10 (30%) C/D cases had MAP readings <85 mm Hg. In data adjusted for age, injury level, and triage time a 5 mm Hg increase in the lowest MAP value was associated with a 34% increase in the odds of having motor incomplete injury at acute presentation (adjusted odds ratio=1.34; 95% CI: 1.11-1.61; P =0.002). CONCLUSION An important observation with implications for timely and selective cardiovascular resuscitation during SCI prehospital care involves significant negative associations between the depth of systemic hypotension and preserved functional neuroanatomy. Regardless of the mechanism, our confounder-adjusted logistic regression model extends in-hospital evidence and provides a conceptual bedside-bench framework for future investigations.
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Affiliation(s)
- Jillian M Clark
- Centre for Orthopaedics and Trauma Research, School of Medicine
| | - Jana M Bednarz
- Data, Design and Statistics Service, Adelaide Health Technology Assessment, School of Public Health
| | - Peter E Batchelor
- Department of Neurology, University Hospital Geelong, Geelong, Victoria
| | - Peta Skeers
- NHMRC Clinical Trial Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Brian J C Freeman
- Royal Adelaide Hospital, Centre for Orthopaedic and Trauma Research, University of Adelaide, Adelaide, South Australia
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Agostinello J, Battistuzzo CR, Batchelor PE. Early clinical predictors of pneumonia in critically ill spinal cord injured individuals: a retrospective cohort study. Spinal Cord 2018; 57:41-48. [PMID: 30262877 DOI: 10.1038/s41393-018-0196-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 08/18/2018] [Accepted: 08/29/2018] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN Retrospective cohort. OBJECTIVES Pneumonia is the dominant complication following traumatic spinal cord injury (SCI) and profoundly impacts morbidity by prolonging length of stay and worsening neurological outcome. The aims of this study were to determine the key predictors of clinically important pneumonia (CIP); and to examine the impact of CIP on resource utilisation in critically ill acute traumatic SCI individuals between 2010 and 2015. SETTING Alfred and Austin Hospitals (Melbourne, Australia). METHODS Data were extracted from the medical records of 93 cases of acute traumatic SCI resulting in ISNCSCI C3-L1 level of injury requiring admission to the intensive care unit and aged between 15 and 70 years. Patients with life-threatening injuries, not requiring spinal surgery, palliated within 7 days of injury, diagnosis of traumatic central cord syndrome or with poor general health, were excluded. RESULTS A total of 33 episodes of CIP were observed. Median time to CIP diagnosis was 65 h (IQR: 42-93) and median time to spinal surgery was 22 h (IQR: 12-32). Four key predictors were identified; male gender (OR: 18.3, CI: 1.9-174.9, p = 0.001), motor complete injury (OR: 10.1, CI: 1.1-92.1, p = 0.011), presence of chest trauma (OR: 4.5, CI: 1.4-14.4, p = 0.007) and delayed intubation (HR: 6.8, CI: 1.6-28.6, p = 0.009). CONCLUSIONS This study identifies four key predictors involved in elevated pneumonia risk; male gender, motor complete injury, presence of chest trauma and delayed intubation, enabling the future synthesis of a pneumonia prediction tool for use in the acute postinjury period.
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Affiliation(s)
- Jacqui Agostinello
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, VIC, Australia.
| | - Camila R Battistuzzo
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, VIC, Australia
| | - Peter E Batchelor
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Royal Parade, VIC, Australia
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Skeers P, Battistuzzo CR, Clark JM, Bernard S, Freeman BJC, Batchelor PE. Acute Thoracolumbar Spinal Cord Injury: Relationship of Cord Compression to Neurological Outcome. J Bone Joint Surg Am 2018; 100:305-315. [PMID: 29462034 DOI: 10.2106/jbjs.16.00995] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Spinal cord injury in the cervical spine is commonly accompanied by cord compression and urgent surgical decompression may improve neurological recovery. However, the extent of spinal cord compression and its relationship to neurological recovery following traumatic thoracolumbar spinal cord injury is unclear. The purpose of this study was to quantify maximum cord compression following thoracolumbar spinal cord injury and to assess the relationship among cord compression, cord swelling, and eventual clinical outcome. METHODS The medical records of patients who were 15 to 70 years of age, were admitted with a traumatic thoracolumbar spinal cord injury (T1 to L1), and underwent a spinal surgical procedure were examined. Patients with penetrating injuries and multitrauma were excluded. Maximal osseous canal compromise and maximal spinal cord compression were measured on preoperative mid-sagittal computed tomography (CT) scans and T2-weighted magnetic resonance imaging (MRI) by observers blinded to patient outcome. The American Spinal Injury Association (ASIA) Impairment Scale (AIS) grades from acute hospital admission (≤24 hours of injury) and rehabilitation discharge were used to measure clinical outcome. Relationships among spinal cord compression, canal compromise, and initial and final AIS grades were assessed via univariate and multivariate analyses. RESULTS Fifty-three patients with thoracolumbar spinal cord injury were included in this study. The overall mean maximal spinal cord compression (and standard deviation) was 40% ± 21%. There was a significant relationship between median spinal cord compression and final AIS grade, with grade-A patients (complete injury) exhibiting greater compression than grade-C and D patients (incomplete injury) (p < 0.05). Multivariate logistic regression identified mean spinal cord compression as independently influencing the likelihood of complete spinal cord injury (p < 0.01). CONCLUSIONS Traumatic thoracolumbar spinal cord injury is commonly accompanied by substantial cord compression. Greater cord compression is associated with an increased likelihood of severe neurological deficits (complete injury) following thoracolumbar spinal cord injury. LEVEL OF EVIDENCE Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
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Affiliation(s)
- Peta Skeers
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Melbourne, Victoria, Australia
| | - Camila R Battistuzzo
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Melbourne, Victoria, Australia
| | - Jillian M Clark
- Centre for Orthopaedic and Trauma Research, Faculty of Health Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Stephen Bernard
- Intensive Care Unit, The Alfred Hospital, Melbourne, Victoria, Australia
| | - Brian J C Freeman
- Centre for Orthopaedic and Trauma Research, Faculty of Health Sciences, The University of Adelaide, Adelaide, South Australia, Australia.,Spinal Injuries Unit, Department of Orthopaedics and Trauma, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Peter E Batchelor
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Melbourne, Victoria, Australia
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Battistuzzo CR, Smith K, Skeers P, Armstrong A, Clark J, Agostinello J, Cox S, Bernard S, Freeman BJ, Dunlop SA, Batchelor PE. Early Rapid Neurological Assessment for Acute Spinal Cord Injury Trials. J Neurotrauma 2016; 33:1936-1945. [DOI: 10.1089/neu.2015.4360] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- Camila R. Battistuzzo
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, VIC, Australia
| | - Karen Smith
- Department of Epidemiology and Preventive Medicine, Monash University and Ambulance Victoria, Melbourne VIC, Australia
| | - Peta Skeers
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, VIC, Australia
| | - Alex Armstrong
- School of Animal Biology, The University of Western Australia, Perth, WA, Australia
| | - Jillian Clark
- Centre for Orthopaedic and Trauma Research, Faculty of Health Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Jacqui Agostinello
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, VIC, Australia
| | - Shelley Cox
- Department of Epidemiology and Preventive Medicine, Monash University and Ambulance Victoria, Melbourne VIC, Australia
| | - Stephen Bernard
- Department of Epidemiology and Preventive Medicine, Monash University and Ambulance Victoria, Melbourne VIC, Australia
| | - Brian J.C. Freeman
- Centre for Orthopaedic and Trauma Research, Faculty of Health Sciences, The University of Adelaide, Adelaide, SA, Australia
- Department of Orthopaedics and Trauma, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Sarah A. Dunlop
- School of Animal Biology, The University of Western Australia, Perth, WA, Australia
| | - Peter E. Batchelor
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, VIC, Australia
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Battistuzzo CR, Armstrong A, Clark J, Worley L, Sharwood L, Lin P, Rooke G, Skeers P, Nolan S, Geraghty T, Nunn A, Brown DJ, Hill S, Alexander J, Millard M, Cox SF, Rao S, Watts A, Goods L, Allison GT, Agostinello J, Cameron PA, Mosley I, Liew SM, Geddes T, Middleton J, Buchanan J, Rosenfeld JV, Bernard S, Atresh S, Patel A, Schouten R, Freeman BJ, Dunlop SA, Batchelor PE. Early Decompression following Cervical Spinal Cord Injury: Examining the Process of Care from Accident Scene to Surgery. J Neurotrauma 2016; 33:1161-9. [DOI: 10.1089/neu.2015.4207] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Affiliation(s)
- Camila R. Battistuzzo
- Department of Medicine (Royal Melbourne Hospital), the University of Melbourne, Melbourne, Australia
| | - Alex Armstrong
- School of Animal Biology, the University of Western Australia, Perth Australia
| | - Jillian Clark
- Center for Orthopedic and Trauma Research, the University of Adelaide, Adelaide, Australia
| | - Laura Worley
- Queensland Spinal Injuries Service, Princess Alexandra Hospital, Woolloongabba, Australia
| | - Lisa Sharwood
- John Walsh Center for Rehabilitation Research, the University of Sydney, Sydney, Australia
| | - Peny Lin
- Orthopedic Department, Middlemore Hospital, Auckland, New Zealand
| | - Gareth Rooke
- Orthopedic Department, Christchurch Hospital, Christchurch, New Zealand
| | - Peta Skeers
- Department of Medicine (Royal Melbourne Hospital), the University of Melbourne, Melbourne, Australia
| | - Sherilyn Nolan
- School of Animal Biology, the University of Western Australia, Perth Australia
| | - Timothy Geraghty
- Queensland Spinal Injuries Service, Princess Alexandra Hospital, Woolloongabba, Australia
| | - Andrew Nunn
- Victorian Spinal Cord Service, Austin Hospital, Melbourne, Australia
| | | | - Steven Hill
- Victorian Spinal Cord Service, Austin Hospital, Melbourne, Australia
| | - Janette Alexander
- Victorian Spinal Cord Service, Austin Hospital, Melbourne, Australia
| | - Melinda Millard
- Victorian Spinal Cord Service, Austin Hospital, Melbourne, Australia
| | - Susan F. Cox
- Neuroscience Trials Australia, the Florey Institute of Neuroscience, Melbourne, Australia
| | - Sudhakar Rao
- Trauma Service, Royal Perth Hospital, Perth, Australia
| | - Ann Watts
- Spinal Unit, Royal Perth Hospital, Perth, Australia
| | - Louise Goods
- School of Animal Biology, the University of Western Australia, Perth Australia
| | - Garry T. Allison
- School of Physiotherapy and Exercise Science, Curtin University, Bentley, Australia
| | - Jacqui Agostinello
- Department of Medicine (Royal Melbourne Hospital), the University of Melbourne, Melbourne, Australia
| | - Peter A. Cameron
- Emergency and Trauma Center, the Alfred Hospital, Melbourne, Australia
| | - Ian Mosley
- College of Science, Health and Engineering, La Trobe University, Melbourne, Australia
| | - Susan M. Liew
- Department of Orthopedic Surgery, the Alfred Hospital, Melbourne, Australia
| | - Tom Geddes
- Orthopedic Department, Middlemore Hospital, Auckland, New Zealand
| | - James Middleton
- John Walsh Center for Rehabilitation Research, the University of Sydney, Sydney, Australia
| | - John Buchanan
- Department of Physiotherapy, Royal Perth Hospital, Perth, Australia
| | | | - Stephen Bernard
- Intensive Care Unit, the Alfred Hospital, Melbourne, Australia
| | - Sridhar Atresh
- Queensland Spinal Injuries Service, Princess Alexandra Hospital, Woolloongabba, Australia
| | - Alpesh Patel
- Orthopedic Department, Middlemore Hospital, Auckland, New Zealand
| | - Rowan Schouten
- Orthopedic Department, Christchurch Hospital, Christchurch, New Zealand
| | - Brian J.C. Freeman
- Department of Orthopedics and Trauma, the University of Adelaide, Adelaide, Australia
| | - Sarah A. Dunlop
- School of Animal Biology, the University of Western Australia, Perth Australia
| | - Peter E. Batchelor
- Department of Medicine (Royal Melbourne Hospital), the University of Melbourne, Melbourne, Australia
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Middleton JW, Piccenna L, Lindsay Gruen R, Williams S, Creasey G, Dunlop S, Brown D, Batchelor PE, Berlowitz DJ, Coates S, Dunn JA, Furness JB, Galea MP, Geraghty T, Kwon BK, Urquhart S, Yates D, Bragge P. Developing a spinal cord injury research strategy using a structured process of evidence review and stakeholder dialogue. Part III: outcomes. Spinal Cord 2015; 53:729-37. [DOI: 10.1038/sc.2015.87] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 04/16/2015] [Accepted: 04/17/2015] [Indexed: 11/09/2022]
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Antonic A, Dottori M, Leung J, Sidon K, Batchelor PE, Wilson W, Macleod MR, Howells DW. Hypothermia protects human neurons. Int J Stroke 2014; 9:544-52. [PMID: 24393199 PMCID: PMC4235397 DOI: 10.1111/ijs.12224] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 10/14/2013] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND AIMS Hypothermia provides neuroprotection after cardiac arrest, hypoxic-ischemic encephalopathy, and in animal models of ischemic stroke. However, as drug development for stroke has been beset by translational failure, we sought additional evidence that hypothermia protects human neurons against ischemic injury. METHODS Human embryonic stem cells were cultured and differentiated to provide a source of neurons expressing β III tubulin, microtubule-associated protein 2, and the Neuronal Nuclei antigen. Oxygen deprivation, oxygen-glucose deprivation, and H2 O2 -induced oxidative stress were used to induce relevant injury. RESULTS Hypothermia to 33°C protected these human neurons against H2 O2 -induced oxidative stress reducing lactate dehydrogenase release and Terminal deoxynucleotidyl transferase dUTP nick end labeling-staining by 53% (P ≤ 0·0001; 95% confidence interval 34·8-71·04) and 42% (P ≤ 0·0001; 95% confidence interval 27·5-56·6), respectively, after 24 h in culture. Hypothermia provided similar protection against oxygen-glucose deprivation (42%, P ≤ 0·001, 95% confidence interval 18·3-71·3 and 26%, P ≤ 0·001; 95% confidence interval 12·4-52·2, respectively) but provided no protection against oxygen deprivation alone. Protection (21%) persisted against H2 O2 -induced oxidative stress even when hypothermia was initiated six-hours after onset of injury (P ≤ 0·05; 95% confidence interval 0·57-43·1). CONCLUSION We conclude that hypothermia protects stem cell-derived human neurons against insults relevant to stroke over a clinically relevant time frame. Protection against H2 O2 -induced injury and combined oxygen and glucose deprivation but not against oxygen deprivation alone suggests an interaction in which protection benefits from reduction in available glucose under some but not all circumstances.
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Affiliation(s)
- Ana Antonic
- Florey Institute of Neuroscience and Mental HealthHeidelberg, Vic, Australia
- Department of Medicine, University of MelbourneHeidelberg, Vic, Australia
| | - Mirella Dottori
- Centre for Neuroscience Research, Department of Anatomy and Neuroscience, University of MelbourneMelbourne, Vic, Australia
| | - Jessie Leung
- Centre for Neuroscience Research, Department of Anatomy and Neuroscience, University of MelbourneMelbourne, Vic, Australia
| | - Kate Sidon
- Florey Institute of Neuroscience and Mental HealthHeidelberg, Vic, Australia
- Department of Medicine, University of MelbourneHeidelberg, Vic, Australia
| | - Peter E Batchelor
- Department of Medicine, University of MelbourneHeidelberg, Vic, Australia
| | - William Wilson
- CSIRO Mathematics, Informatics and Statistics, Riverside Life Sciences PrecinctNorth Ryde, NSW, Australia
| | - Malcolm R Macleod
- Department of Clinical Neurosciences, Western General Hospital, University of EdinburghEdinburgh, UK
| | - David W Howells
- Florey Institute of Neuroscience and Mental HealthHeidelberg, Vic, Australia
- Department of Medicine, University of MelbourneHeidelberg, Vic, Australia
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Antonic A, Sena ES, Lees JS, Wills TE, Skeers P, Batchelor PE, Macleod MR, Howells DW. Stem cell transplantation in traumatic spinal cord injury: a systematic review and meta-analysis of animal studies. PLoS Biol 2013; 11:e1001738. [PMID: 24358022 PMCID: PMC3866091 DOI: 10.1371/journal.pbio.1001738] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 11/01/2013] [Indexed: 12/18/2022] Open
Abstract
Spinal cord injury (SCI) is a devastating condition that causes substantial morbidity and mortality and for which no treatments are available. Stem cells offer some promise in the restoration of neurological function. We used systematic review, meta-analysis, and meta-regression to study the impact of stem cell biology and experimental design on motor and sensory outcomes following stem cell treatments in animal models of SCI. One hundred and fifty-six publications using 45 different stem cell preparations met our prespecified inclusion criteria. Only one publication used autologous stem cells. Overall, allogeneic stem cell treatment appears to improve both motor (effect size, 27.2%; 95% Confidence Interval [CI], 25.0%-29.4%; 312 comparisons in 5,628 animals) and sensory (effect size, 26.3%; 95% CI, 7.9%-44.7%; 23 comparisons in 473 animals) outcome. For sensory outcome, most heterogeneity between experiments was accounted for by facets of stem cell biology. Differentiation before implantation and intravenous route of delivery favoured better outcome. Stem cell implantation did not appear to improve sensory outcome in female animals and appeared to be enhanced by isoflurane anaesthesia. Biological plausibility was supported by the presence of a dose-response relationship. For motor outcome, facets of stem cell biology had little detectable effect. Instead most heterogeneity could be explained by the experimental modelling and the outcome measure used. The location of injury, method of injury induction, and presence of immunosuppression all had an impact. Reporting of measures to reduce bias was higher than has been seen in other neuroscience domains but were still suboptimal. Motor outcomes studies that did not report the blinded assessment of outcome gave inflated estimates of efficacy. Extensive recent preclinical literature suggests that stem-cell-based therapies may offer promise, however the impact of compromised internal validity and publication bias mean that efficacy is likely to be somewhat lower than reported here.
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Affiliation(s)
- Ana Antonic
- Department of Medicine, University of Melbourne Lance Townsend Building, Austin Hospital, Heidelberg, Victoria, Australia
| | - Emily S. Sena
- Florey Institute of Neuroscience and Mental Health, Victoria, Australia
- Division of Clinical Neurosciences, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Jennifer S. Lees
- Division of Clinical Neurosciences, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Taryn E. Wills
- Department of Medicine, University of Melbourne Lance Townsend Building, Austin Hospital, Heidelberg, Victoria, Australia
- Florey Institute of Neuroscience and Mental Health, Victoria, Australia
| | - Peta Skeers
- Department of Medicine, University of Melbourne Lance Townsend Building, Austin Hospital, Heidelberg, Victoria, Australia
| | - Peter E. Batchelor
- Department of Medicine, University of Melbourne Lance Townsend Building, Austin Hospital, Heidelberg, Victoria, Australia
- Florey Institute of Neuroscience and Mental Health, Victoria, Australia
| | - Malcolm R. Macleod
- Division of Clinical Neurosciences, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - David W. Howells
- Florey Institute of Neuroscience and Mental Health, Victoria, Australia
- * E-mail:
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Wills TE, Batchelor PE, Kerr NF, Sidon K, Katz M, Loy C, Howells DW. Corticospinal tract sprouting in the injured rat spinal cord stimulated by Schwann cell preconditioning of the motor cortex. Neurol Res 2013; 35:763-72. [DOI: 10.1179/1743132813y.0000000199] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Affiliation(s)
- Taryn E Wills
- Florey Institute of Neuroscience & Mental HealthUniversity of Melbourne, Australia
| | - Peter E Batchelor
- Florey Institute of Neuroscience & Mental HealthUniversity of Melbourne, Australia
| | - Nicole F Kerr
- Florey Institute of Neuroscience & Mental HealthUniversity of Melbourne, Australia
| | - Kate Sidon
- Florey Institute of Neuroscience & Mental HealthUniversity of Melbourne, Australia
| | - Melissa Katz
- Florey Institute of Neuroscience & Mental HealthUniversity of Melbourne, Australia
| | - Candace Loy
- Florey Institute of Neuroscience & Mental HealthUniversity of Melbourne, Australia
| | - David W Howells
- Florey Institute of Neuroscience & Mental HealthUniversity of Melbourne, Australia
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Batchelor PE, Wills TE, Skeers P, Battistuzzo CR, Macleod MR, Howells DW, Sena ES. Meta-analysis of pre-clinical studies of early decompression in acute spinal cord injury: a battle of time and pressure. PLoS One 2013; 8:e72659. [PMID: 24009695 PMCID: PMC3751840 DOI: 10.1371/journal.pone.0072659] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 07/12/2013] [Indexed: 12/05/2022] Open
Abstract
Background The use of early decompression in the management of acute spinal cord injury (SCI) remains contentious despite many pre-clinical studies demonstrating benefits and a small number of supportive clinical studies. Although the pre-clinical literature favours the concept of early decompression, translation is hindered by uncertainties regarding overall treatment efficacy and timing of decompression. Methods We performed meta-analysis to examine the pre-clinical literature on acute decompression of the injured spinal cord. Three databases were utilised; PubMed, ISI Web of Science and Embase. Our inclusion criteria consisted of (i) the reporting of efficacy of decompression at various time intervals (ii) number of animals and (iii) the mean outcome and variance in each group. Random effects meta-analysis was used and the impact of study design characteristics assessed with meta-regression. Results Overall, decompression improved behavioural outcome by 35.1% (95%CI 27.4-42.8; I2=94%, p<0.001). Measures to minimise bias were not routinely reported with blinding associated with a smaller but still significant benefit. Publication bias likely also contributed to an overestimation of efficacy. Meta-regression demonstrated a number of factors affecting outcome, notably compressive pressure and duration (adjusted r2=0.204, p<0.002), with increased pressure and longer durations of compression associated with smaller treatment effects. Plotting the compressive pressure against the duration of compression resulting in paraplegia in individual studies revealed a power law relationship; high compressive forces quickly resulted in paraplegia, while low compressive forces accompanying canal narrowing resulted in paresis over many hours. Conclusion These data suggest early decompression improves neurobehavioural deficits in animal models of SCI. Although much of the literature had limited internal validity, benefit was maintained across high quality studies. The close relationship of compressive pressure to the rate of development of severe neurological injury suggests that pressure local to the site of injury might be a useful parameter determining the urgency of decompression.
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Affiliation(s)
- Peter E. Batchelor
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
- Department of Medicine, University of Melbourne, Heidelberg, Victoria, Australia
- * E-mail:
| | - Taryn E. Wills
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
- Department of Medicine, University of Melbourne, Heidelberg, Victoria, Australia
| | - Peta Skeers
- Department of Medicine, University of Melbourne, Heidelberg, Victoria, Australia
| | | | - Malcolm R. Macleod
- Division of Clinical Neurosciences, University of Edinburgh, Edinburgh, United Kingdom
| | - David W. Howells
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
| | - Emily S. Sena
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
- Division of Clinical Neurosciences, University of Edinburgh, Edinburgh, United Kingdom
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Sena ES, Jeffreys AL, Cox SF, Sastra SA, Churilov L, Rewell S, Batchelor PE, van der Worp HB, Macleod MR, Howells DW. The Benefit of Hypothermia in Experimental Ischemic Stroke is Not Affected by Pethidine. Int J Stroke 2012; 8:180-5. [DOI: 10.1111/j.1747-4949.2012.00834.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Background Hypothermia is a promising experimental treatment for acute ischemic stroke. Human trials are still at an early stage, with the focus now on using hypothermia in awake patients. Pethidine (meperidine) is the principle agent used to control shivering in humans; however, whether it has any modulating effects on the neuroprotective efficacy of hypothermia is unknown. Aim The aim of this study was to determine if pethidine influences the neuroprotective effect of hypothermia in experimental stroke. Methods Seventy-two male spontaneously hypertensive rats were anesthetized with isoflurane and randomly assigned to either normothermia (37·4°C rectal temperature); hypothermia (33°C maintained for 130 mins); normothermia plus pethidine (2·5 mg/kg); or hypothermia plus pethidine. Temporary (90 mins) endovascular occlusion of the middle cerebral artery was induced blinded to treatment allocation and was confirmed with laser Doppler flowmetry. Pethidine and cooling were started immediately after vessel occlusion. Animals in the normothermia group had active temperature management using a heat lamp and fan. Assessments of outcome were carried out 24 after the induction of injury. Results Thirteen animals met our prespecified criteria for exclusion, and data for 59 rats were presented here. Hypothermia was associated with a 63% reduction in infarct size, and pethidine had no significant impact on the efficacy of hypothermia. No effects were observed in neurobehavioral outcome or edema volume across experimental groups. Conclusions The effects of hypothermia in a model of focal ischemia are not affected by administration of pethidine.
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Affiliation(s)
- Emily S. Sena
- Centre for Clinical Brain Sciences, Division of Clinical Neurosciences, University of Edinburgh, Edinburgh, UK
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
- National Stroke Research Institute & Florey Neurosciences Institute, Heidelberg, Victoria, Australia
| | - Amy L. Jeffreys
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Susan F. Cox
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Stephen A. Sastra
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Leonid Churilov
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
- National Stroke Research Institute & Florey Neurosciences Institute, Heidelberg, Victoria, Australia
- Department of Mathematics and Statistics, University of Melbourne, Melbourne, Victoria, Australia
| | - Sarah Rewell
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
- National Stroke Research Institute & Florey Neurosciences Institute, Heidelberg, Victoria, Australia
| | - Peter E. Batchelor
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - H. Bart van der Worp
- Department of Neurology, Rudolf Magnus Institute of Neuroscience, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Malcolm R. Macleod
- Centre for Clinical Brain Sciences, Division of Clinical Neurosciences, University of Edinburgh, Edinburgh, UK
| | - David W. Howells
- National Stroke Research Institute & Florey Neurosciences Institute, Heidelberg, Victoria, Australia
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12
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Batchelor PE, Kerr NF, Gatt AM, Cox SF, Ghasem-Zadeh A, Wills TE, Sidon TK, Howells DW. Intracanal pressure in compressive spinal cord injury: reduction with hypothermia. J Neurotrauma 2011; 28:809-20. [PMID: 21250916 DOI: 10.1089/neu.2010.1622] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Most cases of human spinal cord injury (SCI) are accompanied by continuing cord compression. Experimentally, compression results in rapid neurological decline over hours, suggesting a rise in intracanal pressure local to the site of injury. The aim of this study was to measure the rise in local intracanal pressure accompanying progressive canal occlusion and to determine the relationship between raised intracanal pressure and neurological outcome. We also aimed to establish whether hypothermia was able to reduce raised intracanal pressure. We demonstrate that, following SCI in F344 rats, local intracanal pressure remains near normal until canal occlusion exceeds 30% of diameter, whereupon a rapid increase in pressure occurs. Intracanal pressure appears to be an important determinant of neurological recovery, with poor long-term behavioural and histological outcomes in animals subject to 8 h of 45% canal occlusion, in which intracanal pressure is significantly elevated. In contrast, good neurological recovery occurs in animals with near normal intracanal pressure (animals undergoing 8 h of 30% canal occlusion or those undergoing immediate decompression). We further demonstrate that hypothermia is an effective therapy to control raised intracanal pressure, rapidly reducing elevated intracanal pressure accompanying critical (45%) canal occlusion to near normal. Overall these data indicate that following SCI only limited canal narrowing is tolerated before local intracanal pressure rapidly rises, inducing a sharp decline in neurological outcome. Raised intracanal pressure can be controlled with hypothermia, which may be a useful therapy to emergently decompress the spinal cord prior to surgical decompression.
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Affiliation(s)
- Peter E Batchelor
- Department of Medicine, National Stroke Research Institute and University of Melbourne, Austin Health, Heidelberg, Victoria, Australia.
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13
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Batchelor PE, Kerr NF, Gatt AM, Aleksoska E, Cox SF, Ghasem-Zadeh A, Wills TE, Howells DW. Hypothermia Prior to Decompression: Buying Time for Treatment of Acute Spinal Cord Injury. J Neurotrauma 2010; 27:1357-68. [DOI: 10.1089/neu.2010.1360] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Affiliation(s)
- Peter E. Batchelor
- National Stroke Research Institute and University of Melbourne, Department of Medicine, Heidelberg, Victoria, Australia
| | - Nicole F. Kerr
- National Stroke Research Institute and University of Melbourne, Department of Medicine, Heidelberg, Victoria, Australia
| | - Amy M. Gatt
- National Stroke Research Institute and University of Melbourne, Department of Medicine, Heidelberg, Victoria, Australia
| | - Elena Aleksoska
- National Stroke Research Institute and University of Melbourne, Department of Medicine, Heidelberg, Victoria, Australia
| | - Susan F. Cox
- National Stroke Research Institute and University of Melbourne, Department of Medicine, Heidelberg, Victoria, Australia
| | - Ali Ghasem-Zadeh
- Endocrinology Centre of Excellence, Austin Health, Heidelberg, Victoria, Australia
| | - Taryn E. Wills
- National Stroke Research Institute and University of Melbourne, Department of Medicine, Heidelberg, Victoria, Australia
| | - David W. Howells
- National Stroke Research Institute and University of Melbourne, Department of Medicine, Heidelberg, Victoria, Australia
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14
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Rewell SSJ, Fernandez JA, Cox SF, Spratt NJ, Hogan L, Aleksoska E, van Raay L, Liberatore GT, Batchelor PE, Howells DW. Inducing stroke in aged, hypertensive, diabetic rats. J Cereb Blood Flow Metab 2010; 30:729-33. [PMID: 20068574 PMCID: PMC2949155 DOI: 10.1038/jcbfm.2009.273] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Animal models of ischemic stroke often neglect comorbidities common in patients. This study shows the feasibility of inducing stroke by 2 h of thread occlusion of the middle cerebral artery in aged (56 week old) spontaneously hypertensive rats (SHRs) with both acute (2 weeks) and chronic (36 weeks) diabetes. After modifying the streptozotocin dosing regimen to ensure that old SHRs survived the induction of diabetes, few died after induction of stroke. Induction of stroke is feasible in rats with multiple comorbidities. Inclusion of such comorbid animals may improve translation from the research laboratory to the clinic.
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Affiliation(s)
- Sarah S J Rewell
- National Stroke Research Institute and University of Melbourne Department of Medicine, Austin Health, Heidelberg, Victoria, Australia
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15
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Batchelor PE, Tan S, Wills TE, Porritt MJ, Howells DW. Comparison of inflammation in the brain and spinal cord following mechanical injury. J Neurotrauma 2009; 25:1217-25. [PMID: 18986223 DOI: 10.1089/neu.2007.0308] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Inflammation in the CNS predominantly involves microglia and macrophages, and is believed to be a significant cause of secondary injury following trauma. This study compares the microglial and macrophage response in the rat brain and spinal cord following discrete mechanical injury to better appreciate the degree to which these cells could contribute to secondary damage in these areas. We find that, 1 week after injury, the microglial and macrophage response is significantly greater in the spinal cord compared to the brain. This is the case for injuries to both gray and white matter. In addition, we observed a greater inflammatory response in white matter compared to gray matter within both the brain and spinal cord. Because activated microglia and macrophages appear to be effectors of secondary damage, a greater degree of inflammation in the spinal cord is likely to result in more extensive secondary damage. Tissue saving strategies utilizing anti-inflammatory treatments may therefore be more useful in traumatic spinal cord than brain injury.
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Affiliation(s)
- Peter E Batchelor
- Department of Medicine, University of Melbourne, Austin Health, Victoria, Australia
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16
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Porritt MJ, Batchelor PE, Howells DW. Inhibiting BDNF expression by antisense oligonucleotide infusion causes loss of nigral dopaminergic neurons. Exp Neurol 2005; 192:226-34. [PMID: 15698637 DOI: 10.1016/j.expneurol.2004.11.030] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Revised: 10/27/2004] [Accepted: 11/10/2004] [Indexed: 01/09/2023]
Abstract
Brain derived neurotrophic factor (BDNF) expression is significantly reduced in the Parkinson's disease substantia nigra. This neurotrophin has potent affects on dopaminergic neuron survival protecting them from the neurotoxins MPTP and 6-hydroxydopamine (6-OHDA) commonly used to create animal models of Parkinson's disease and also promoting dopaminergic axonal sprouting. In this study, we demonstrate that an antisense oligonucleotide infusion (200 nM for 28 days) to prevent BDNF production in the substantia nigra of rats mimics many features of the classical animal models of Parkinson's disease. 62% of antisense treated rats rotate (P < or = 0.05) in response to dopaminergic receptor stimulation by apomorphine. 40% of substantia nigra pars compacta tyrosine hydroxylase immunoreactive neurons are lost (P < or = 0.00001) and dopamine uptake site density measured by (3)H-mazindol autoradiography is reduced by 34% (P < or = 0.005). Loss of haematoxylin and eosin stained nigral neurons is significant (P < or = 0.0001) but less extensive (34%). These observations indicate that loss of BDNF expression leads both to down regulation of the dopaminergic phenotype and to dopaminergic neuronal death. Therefore, reduced BDNF mRNA expression in Parkinson's disease substantia nigra may contribute directly to the death of nigral dopaminergic neurons and the development of Parkinson's disease.
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Affiliation(s)
- M J Porritt
- Department of Medicine, University of Melbourne, Level 7, Lance Townsend Building, Austin Health, Studley Road, Heidelberg, Vic 3084 Australia
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17
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Abstract
Following injury to the CNS, severed axons undergo a phase of abortive sprouting in the vicinity of the wound, but do not spontaneously re-grow or regenerate. From a long history of attempts to stimulate regeneraion, a major strategy that has been developed clinically is the implantation of tissue into denervated target regions. Unfortunately trials have so far not borne out the promise that this would prove a useful therapy for disorders such as Parkinson's disease. Many strategies have also been developed to stimulate the regeneration of axons across sites of injury, particularly in the spinal cord. Animal data have demonstrated that some of these approaches hold promise and that the spinal cord has a remarkable degree of intrinsic plasticity. Attempts are now being made to utilize experimental techniques in spinal patients.
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Affiliation(s)
- Peter E Batchelor
- Departments of Medicine and Neurology, University of Melbourne, Austin and Repatriation Medical Centre, Vic. 3084, Heidelberg, Australia
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18
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Batchelor PE, Porritt MJ, Martinello P, Parish CL, Liberatore GT, Donnan GA, Howells DW. Macrophages and Microglia Produce Local Trophic Gradients That Stimulate Axonal Sprouting Toward but Not beyond the Wound Edge. Mol Cell Neurosci 2002; 21:436-53. [PMID: 12498785 DOI: 10.1006/mcne.2002.1185] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Following injury to the mammalian CNS, axons sprout in the vicinity of the wound margin. Growth then ceases and axons fail to cross the lesion site. In this study, using dopaminergic sprouting in the injured striatum as a model system, we have examined the relationship of periwound sprouting fibers to reactive glia and macrophages. In the first week after injury we find that sprouting fibers form intimate relationships with activated microglia as they traverse toward the wound edge. Once at the wound edge, complicated plexuses of fibers form around individual macrophages. Axons, however, fail to grow further into the interior of the wound despite the presence of many macrophages in this location. We find that the expression of BDNF by activated microglia progressively increases as the wound edge is approached, while GDNF expression by macrophages is highest at the immediate wound margin. In contrast, the expression of both factors is substantially reduced within the macrophage-filled interior of the wound. Our data suggest that periwound sprouting fibers grow toward the wound margin along an increasing trophic gradient generated by progressively microglial and macrophage activation. Once at the wound edge, sprouting ceases over macrophages at the point of maximal neurotrophic factor expression and further axonal growth into the relatively poor trophic environment of the wound core fails to occur.
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Affiliation(s)
- P E Batchelor
- Departments of Medicine, Neurology, The University of Melbourne, Austin and Repatriation Medical Centre, Heidelberg, Victoria, 3084, Australia
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Batchelor PE, Porritt MJ, Nilsson SK, Bertoncello I, Donnan GA, Howells DW. Periwound dopaminergic sprouting is dependent on numbers of wound macrophages. Eur J Neurosci 2002; 15:826-32. [PMID: 11906524 DOI: 10.1046/j.1460-9568.2002.01914.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Injury to many regions of the central nervous system, including the striatum, results in a periwound or 'abortive' sprouting response. In order to directly evaluate whether macrophages play an important role in stimulating periwound sprouting, osteopetrotic (op/op) mice, which when young are deficient in a variety of macrophage subtypes, were given striatal wounds and the degree of dopaminergic sprouting subsequently assessed. Two weeks postinjury, significantly fewer wound macrophages were present in the striata of op/op mice compared with controls (144 +/- 30.1 in op/op mice vs. 416.6 +/- 82.3 in controls, P < 0.005, analysis performed on a section transecting the middle of the wound). Dopamine transporter immunohistochemistry revealed a marked decrease in the intensity of periwound sprouting in the op/op group of animals. Quantification of this effect using [H3]-mazindol autoradiography confirmed that periwound sprouting was reduced significantly in the op/op mice compared with controls (71.4 +/- 21.7 fmol/mg protein in op/op mice vs. 210.7 +/- 27.1 fmol/mg protein in controls, P < 0.0005). In the two groups of animals the magnitude of the sprouting response in individuals was closely correlated with the number of wound macrophages (R = 0.83, R2 = 0.69). Our findings provide strong support for the crucial involvement of macrophages in inducing dopaminergic sprouting after striatal injury.
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Affiliation(s)
- P E Batchelor
- Departments of Medicine and Neurology, University of Melbourne, Austin and Repatriation Medical Centre, Heidelberg Victoria 3084, Australia
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20
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Howells DW, Porritt MJ, Wong JY, Batchelor PE, Kalnins R, Hughes AJ, Donnan GA. Reduced BDNF mRNA expression in the Parkinson's disease substantia nigra. Exp Neurol 2000; 166:127-35. [PMID: 11031089 DOI: 10.1006/exnr.2000.7483] [Citation(s) in RCA: 351] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Brain-derived neurotrophic factor (BDNF) has potent effects on survival and morphology of dopaminergic neurons and thus its loss could contribute to death of these cells in Parkinson's disease (PD). In situ hybridization revealed that BDNF mRNA is strongly expressed by dopaminergic neurons in control substantia nigra pars compacta (SNpc). In clinically and neuropathologically typical PD, SNpc BDNF mRNA expression is reduced by 70% (P = 0.001). This reduction is due, in part, to loss of dopaminergic neurons which express BDNF. However, surviving dopaminergic neurons in the PD SNpc also expressed less BDNF mRNA (20%, P = 0.02) than their normal counterparts. Moreover, while 15% of control neurons had BDNF mRNA expression >1 SD below the control mean, twice as many (28%) of the surviving PD SNpc dopaminergic neurons had BDNF mRNA expression below this value. This 13% difference in proportions (95% CI 8-17%, P < or = 0.000001) indicates the presence of a subset of neurons in PD with particularly low BDNF mRNA expression. Moreover, both control and PD neurons displayed a direct relationship between the density of BDNF mRNA expression per square micrometer of cell surface and neuronal size (r(2) = 0.93, P </= 0.00001) which was lost only in PD neurons expressing the lowest levels of BDNF mRNA. If BDNF is an autocrine/paracrine factor for SNpc dopaminergic neurons, loss of BDNF-expressing neurons may compromise the well-being of their surviving neighbors. Moreover, neurons expressing particularly low levels of BDNF mRNA may be those at greatest risk of injury in PD and possibly the trigger for the degeneration itself.
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Affiliation(s)
- D W Howells
- Department of Medicine, University of Melbourne, Heidelberg, Victoria, 3084, Australia
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21
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Batchelor PE, Liberatore GT, Porritt MJ, Donnan GA, Howells DW. Inhibition of brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor expression reduces dopaminergic sprouting in the injured striatum. Eur J Neurosci 2000; 12:3462-8. [PMID: 11029615 DOI: 10.1046/j.1460-9568.2000.00239.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
After striatal injury, sprouting dopaminergic fibres grow towards and intimately surround wound macrophages which, together with microglia, express the dopaminergic neurotrophic factors glial cell line-derived neurotrophic factor (GDNF) and brain derived neurotrophic factor (BDNF). To evaluate the importance of these endogenously secreted neurotrophic factors in generating striatal peri-wound dopaminergic sprouting, the peri-wound expression of BDNF or GDNF was inhibited by intrastriatal infusion of antisense oligonucleotides for 2 weeks in mice. Knock-down of both BDNF and GDNF mRNA and protein levels in the wounded striatum were confirmed by in situ hybridization and enzyme-linked immunosorbent assay, respectively. Dopamine transporter immunohisto-chemistry revealed that inhibition of either BDNF or GDNF expression resulted in a marked decrease in the intensity of peri-wound sprouting. Quantification of this effect using [H3]-mazindol autoradiography confirmed that peri-wound sprouting was significantly reduced in mice receiving BDNF or GDNF antisense infusions whilst control infusions of buffered saline or sense oligonucleotides resulted in the pronounced peri-wound sprouting response normally associated with striatal injury. BDNF and GDNF thus appear to be important neurotrophic factors inducing dopaminergic sprouting after striatal injury.
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Affiliation(s)
- P E Batchelor
- Department of Medicine, University of Melbourne, Austin, Australia
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Abstract
A new population of dopaminergic neurons has been identified in Parkinson's disease striatum. These neurons are sufficiently numerous to have an important effect on dopaminergic function in the striatum.
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Batchelor PE, Liberatore GT, Wong JY, Porritt MJ, Frerichs F, Donnan GA, Howells DW. Activated macrophages and microglia induce dopaminergic sprouting in the injured striatum and express brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor. J Neurosci 1999; 19:1708-16. [PMID: 10024357 PMCID: PMC6782182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
Nigrostriatal dopaminergic neurons undergo sprouting around the margins of a striatal wound. The mechanism of this periwound sprouting has been unclear. In this study, we have examined the role played by the macrophage and microglial response that follows striatal injury. Macrophages and activated microglia quickly accumulate after injury and reach their greatest numbers in the first week. Subsequently, the number of both cell types declines rapidly in the first month and thereafter more slowly. Macrophage numbers eventually cease to decline, and a sizable group of these cells remains at the wound site and forms a long-term, highly activated resident population. This population of macrophages expresses increasing amounts of glial cell line-derived neurotrophic factor mRNA with time. Brain-derived neurotrophic factor mRNA is also expressed in and around the wound site. Production of this factor is by both activated microglia and, to a lesser extent, macrophages. The production of these potent dopaminergic neurotrophic factors occurs in a similar spatial distribution to sprouting dopaminergic fibers. Moreover, dopamine transporter-positive dopaminergic neurites can be seen growing toward and embracing hemosiderin-filled wound macrophages. The dopaminergic sprouting that accompanies striatal injury thus appears to result from neurotrophic factor secretion by activated macrophages and microglia at the wound site.
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Affiliation(s)
- P E Batchelor
- Department of Medicine, University of Melbourne, Austin and Repatriation Medical Centre, Heidelberg, Victoria 3084, Australia
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Batchelor PE, Armstrong DM, Blaker SN, Gage FH. Nerve growth factor receptor and choline acetyltransferase colocalization in neurons within the rat forebrain: response to fimbria-fornix transection. J Comp Neurol 1989; 284:187-204. [PMID: 2546981 DOI: 10.1002/cne.902840204] [Citation(s) in RCA: 220] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Although it is well known that magnocellular cholinergic basal forebrain neurons are trophically responsive to nerve growth factor (NGF) and contain NGF receptors (NGFr), the exact distribution of forebrain NGFr-immunoreactive neurons and the degree to which cholinergic neurons are colocalized with them have remained in question. In this study we employed a very sensitive double-labelling method and examined in the same tissue section the distribution and cellular features of NGFr-positive and choline acetyltransferase (ChAT)-immunolabelled neurons within the rat basal forebrain. Throughout this region the majority of magnocellular basal forebrain neurons were immunoreactive for both NGFr and ChAT. However, a small percentage of neurons in the ventral portion of the vertical limb of the diagonal band of Broca were immunoreactive only for NGFr, whereas a larger population of magnocellular neurons in the substantia innominata exhibited only ChAT immunoreactivity. No NGFr-immunoreactive cells were found associated with ChAT-positive neurons in the striatum, neocortex, or hippocampus, and no single-labelled NGFr-immunoreactive neurons were found outside the basal forebrain area, except for a large number of positive-labelled cells along the ventricular walls of the third ventricle. In addition to its function in maintaining the normal integrity of the basal forebrain and cholinergic, peripheral sympathetic, and neural-crest-derived sensory neurons, NGF may also have a role in the growth of these neurons after damage to the nervous system. To examine this postulate the hippocampus was denervated of its septal input and examined 8 weeks later. Two populations of neurons were found to have undergone collateral sprouting--namely, the midline magnocellular cholinergic neurons of the dorsal hippocampus and the sympathetic noradrenergic neurons of the superior cervical ganglion. Both of these neuronal populations also stained strongly for NGFr. In contrast, the small intrinsic cholinergic neurons of the hippocampus exhibited neither sprouting response nor staining for NGFr. In view of these results, we suggest that the differing sprouting responses demonstrated by these three neuronal populations may be due to their responsiveness to NGF, as indicated by the presence or absence of NGF receptors.
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Affiliation(s)
- P E Batchelor
- Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla 92093
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