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Münz F, Datzmann T, Hoffmann A, Gröger M, Mathieu R, Mayer S, Zink F, Gässler H, Wolfschmitt EM, Hogg M, Calzia E, Asfar P, Radermacher P, Kapapa T, Merz T. The Effect of Targeted Hyperoxemia on Brain Immunohistochemistry after Long-Term, Resuscitated Porcine Acute Subdural Hematoma and Hemorrhagic Shock. Int J Mol Sci 2024; 25:6574. [PMID: 38928283 PMCID: PMC11204264 DOI: 10.3390/ijms25126574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Revised: 06/06/2024] [Accepted: 06/11/2024] [Indexed: 06/28/2024] Open
Abstract
Epidemiological data suggest that moderate hyperoxemia may be associated with an improved outcome after traumatic brain injury. In a prospective, randomized investigation of long-term, resuscitated acute subdural hematoma plus hemorrhagic shock (ASDH + HS) in 14 adult, human-sized pigs, targeted hyperoxemia (200 < PaO2 < 250 mmHg vs. normoxemia 80 < PaO2 < 120 mmHg) coincided with improved neurological function. Since brain perfusion, oxygenation and metabolism did not differ, this post hoc study analyzed the available material for the effects of targeted hyperoxemia on cerebral tissue markers of oxidative/nitrosative stress (nitrotyrosine expression), blood-brain barrier integrity (extravascular albumin accumulation) and fluid homeostasis (oxytocin, its receptor and the H2S-producing enzymes cystathionine-β-synthase and cystathionine-γ-lyase). After 2 h of ASDH + HS (0.1 mL/kgBW autologous blood injected into the subdural space and passive removal of 30% of the blood volume), animals were resuscitated for up to 53 h by re-transfusion of shed blood, noradrenaline infusion to maintain cerebral perfusion pressure at baseline levels and hyper-/normoxemia during the first 24 h. Immediate postmortem, bi-hemispheric (i.e., blood-injected and contra-lateral) prefrontal cortex specimens from the base of the sulci underwent immunohistochemistry (% positive tissue staining) analysis of oxidative/nitrosative stress, blood-brain barrier integrity and fluid homeostasis. None of these tissue markers explained any differences in hyperoxemia-related neurological function. Likewise, hyperoxemia exerted no deleterious effects.
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Affiliation(s)
- Franziska Münz
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Ulm, 89081 Ulm, Germany
| | - Thomas Datzmann
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
| | - Andrea Hoffmann
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
| | - Michael Gröger
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
| | - René Mathieu
- Department of Neurosurgery, German Federal Armed Forces Hospital Ulm, 89081 Ulm, Germany
| | - Simon Mayer
- Department of Neurosurgery, German Federal Armed Forces Hospital Ulm, 89081 Ulm, Germany
| | - Fabian Zink
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
| | - Holger Gässler
- Department of Anesthesiology, Intensive Care Medicine, Emergency Medicine and Pain Therapy, German Armed Forces Hospital Ulm, 89081 Ulm, Germany
| | - Eva-Maria Wolfschmitt
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
| | - Melanie Hogg
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
| | - Enrico Calzia
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
| | - Pierre Asfar
- Department of Intensive Care and Hyperbaric Medicine, University Hospital Angers, 49045 Angers, France
| | - Peter Radermacher
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
| | - Thomas Kapapa
- Department of Neurosurgery, University Hospital Ulm, 89081 Ulm, Germany
| | - Tamara Merz
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, 89081 Ulm, Germany (P.R.)
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Ulm, 89081 Ulm, Germany
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Datzmann T, Münz F, Hoffmann A, Moehrke E, Binzenhöfer M, Gröger M, Kapapa T, Mathieu R, Mayer S, Zink F, Gässler H, Wolfschmitt EM, Hogg M, Merz T, Calzia E, Radermacher P, Messerer DAC. An exploratory study investigating the effect of targeted hyperoxemia in a randomized controlled trial in a long-term resuscitated model of combined acute subdural hematoma and hemorrhagic shock in cardiovascular healthy pigs. Front Immunol 2023; 14:1123196. [PMID: 37114041 PMCID: PMC10126345 DOI: 10.3389/fimmu.2023.1123196] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 03/14/2023] [Indexed: 04/29/2023] Open
Abstract
Severe physical injuries and associated traumatic brain injury and/or hemorrhagic shock (HS) remain leading causes of death worldwide, aggravated by accompanying extensive inflammation. Retrospective clinical data indicated an association between mild hyperoxemia and improved survival and outcome. However, corresponding prospective clinical data, including long-term resuscutation, are scarce. Therefore, the present study explored the effect of mild hyperoxemia for 24 hours in a prospective randomized controlled trial in a long-term resuscitated model of combined acute subdural hematoma (ASDH) and HS. ASDH was induced by injecting 0.1 ml × kg-1 autologous blood into the subdural space and HS was triggered by passive removal of blood. After 2 hours, the animals received full resuscitation, including retransfusion of the shed blood and vasopressor support. During the first 24 hours, the animals underwent targeted hyperoxemia (PaO2 = 200 - 250 mmHg) or normoxemia (PaO2 = 80 - 120 mmHg) with a total observation period of 55 hours after the initiation of ASDH and HS. Survival, cardiocirculatory stability, and demand for vasopressor support were comparable between both groups. Likewise, humoral markers of brain injury and systemic inflammation were similar. Multimodal brain monitoring, including microdialysis and partial pressure of O2 in brain tissue, did not show significant differences either, despite a significantly better outcome regarding the modified Glasgow Coma Scale 24 hours after shock that favors hyperoxemia. In summary, the present study reports no deleterious and few beneficial effects of mild targeted hyperoxemia in a clinically relevant model of ASDH and HS with long-term resuscitation in otherwise healthy pigs. Further beneficial effects on neurological function were probably missed due to the high mortality in both experimental groups. The present study remains exploratory due to the unavailability of an a priori power calculation resulting from the lack of necessary data.
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Affiliation(s)
- Thomas Datzmann
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - Franziska Münz
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Ulm, Ulm, Germany
| | - Andrea Hoffmann
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - Elena Moehrke
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - Martha Binzenhöfer
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - Michael Gröger
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - Thomas Kapapa
- Department of Neurosurgery, University Hospital Ulm, Ulm, Germany
| | - René Mathieu
- Department of Neurosurgery, German Federal Armed Forces Hospital Ulm, Ulm, Germany
| | - Simon Mayer
- Department of Neurosurgery, German Federal Armed Forces Hospital Ulm, Ulm, Germany
| | - Fabian Zink
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - Holger Gässler
- Department of Anesthesiology, Intensive Care Medicine, Emergency Medicine and Pain Therapy, German Armed Forces Hospital Ulm, Ulm, Germany
| | - Eva-Maria Wolfschmitt
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - Melanie Hogg
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - Tamara Merz
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Ulm, Ulm, Germany
| | - Enrico Calzia
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - Peter Radermacher
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
| | - David Alexander Christian Messerer
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University, Ulm, Germany
- Department of Transfusion Medicine and Hemostaseology, Friedrich-Alexander University Erlangen-Nuremberg, University Hospital Erlangen, Erlangen, Germany
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Gomaa AA, Farghaly HSM, Ahmed AM, Hemida FK. Intermittent treatment with Apremilast, a phosphodiesterase-4 inhibitor, ameliorates Alzheimer's-like pathology and symptoms through multiple targeting actions in aged T2D rats. Int Immunopharmacol 2023; 117:109927. [PMID: 36848793 DOI: 10.1016/j.intimp.2023.109927] [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: 11/18/2022] [Revised: 01/26/2023] [Accepted: 02/18/2023] [Indexed: 03/01/2023]
Abstract
BACKGROUND Apremilast (Apre), a novel phosphodiesterase-4 (PDE4) inhibitor, has been shown to have anti-inflammatory, immunomodulator, neuroprotective and senolytic properties, therefore, Apre like other PDE4 inhibitors may be a promising candidate for treatment of Alzheimer's disease (AD). OBJECTIVE To evaluate the effectiveness of Apre on Alzheimer's like pathology and symptoms in an animal model. METHODS The effects of Apre and cilostazol, a reference drug, on the behavioral, biochemical, and pathological features of Alzheimer's disease induced by a high-fat/high-fructose diet combined with low-dose streptozotocin (HF/HFr/l-STZ) were investigated. RESULT Apre 5 mg/kg IP/day for 3 consecutive days per week for 8 weeks attenuated memory and learning deficits tested by novel object recognition, Morris water maze and passive avoidance tests. Apre treatment significantly decreased the number of degenerating cells, and abnormal suppression of gene expression of AMPA and NMDA receptor subunits in the cortex and hippocampus of the AD rat model compared to rats that received vehicle. A significant decrease in elevated levels of hippocampal amyloid beta, tau-positive cell count, cholinesterase activity, and hippocampal caspase-3, a biomarker of neurodegeneration, was also observed after treatment with Apre in AD rats compared to rats that received placebo. Furthermore, a significant decrease in pro-inflammatory cytokines, oxidative stress, insulin resistance and GSK-3 was demonstrated in AD aged rats treated by Apre. CONCLUSION Our findings demonstrate that intermittent treatment with Apre can enhance cognitive function in HF/HFr/l-STZ rats which may be related to decreased pro-inflammatory cytokines, oxidative stress, insulin resistance and GSK-3β.
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Affiliation(s)
- Adel A Gomaa
- Department of Pharmacology, Faculty of Medicine, Assiut University, Assiut, Egypt.
| | - Hanan S M Farghaly
- Department of Pharmacology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Asmaa M Ahmed
- Department of Pathology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Fahmy K Hemida
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Assiut University, Assiut, Egypt
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Datzmann T, Messerer DAC, Münz F, Hoffmann A, Gröger M, Mathieu R, Mayer S, Gässler H, Zink F, McCook O, Merz T, Scheuerle A, Wolfschmitt EM, Thebrath T, Zuech S, Calzia E, Asfar P, Radermacher P, Kapapa T. The effect of targeted hyperoxemia in a randomized controlled trial employing a long-term resuscitated, model of combined acute subdural hematoma and hemorrhagic shock in swine with coronary artery disease: An exploratory, hypothesis-generating study. Front Med (Lausanne) 2022; 9:971882. [PMID: 36072939 PMCID: PMC9442904 DOI: 10.3389/fmed.2022.971882] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 08/04/2022] [Indexed: 11/24/2022] Open
Abstract
Controversial evidence is available regarding suitable targets for the arterial O2 tension (PaO2) after traumatic brain injury and/or hemorrhagic shock (HS). We previously demonstrated that hyperoxia during resuscitation from hemorrhagic shock attenuated cardiac injury and renal dysfunction in swine with coronary artery disease. Therefore, this study investigated the impact of targeted hyperoxemia in a long-term, resuscitated model of combined acute subdural hematoma (ASDH)-induced brain injury and HS. The prospective randomized, controlled, resuscitated animal investigation consisted of 15 adult pigs. Combined ASDH plus HS was induced by injection of 0.1 ml/kg autologous blood into the subdural space followed by controlled passive removal of blood. Two hours later, resuscitation was initiated comprising re-transfusion of shed blood, fluids, continuous i.v. noradrenaline, and either hyperoxemia (target PaO2 200 – 250 mmHg) or normoxemia (target PaO2 80 – 120 mmHg) during the first 24 h of the total of 54 h of intensive care. Systemic hemodynamics, intracranial and cerebral perfusion pressures, parameters of brain microdialysis and blood biomarkers of brain injury did not significantly differ between the two groups. According to the experimental protocol, PaO2 was significantly higher in the hyperoxemia group at the end of the intervention period, i.e., at 24 h of resuscitation, which coincided with a higher brain tissue PO2. The latter persisted until the end of observation period. While neurological function as assessed using the veterinary Modified Glasgow Coma Score progressively deteriorated in the control group, it remained unaffected in the hyperoxemia animals, however, without significant intergroup difference. Survival times did not significantly differ in the hyperoxemia and control groups either. Despite being associated with higher brain tissue PO2 levels, which were sustained beyond the intervention period, targeted hyperoxemia exerted neither significantly beneficial nor deleterious effects after combined ASDH and HS in swine with pre-existing coronary artery disease. The unavailability of a power calculation and, thus, the limited number of animals included, are the limitations of the study.
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Affiliation(s)
- Thomas Datzmann
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
- Klinik für Anästhesiologie und Intensivmedizin, Universitätsklinikum Ulm, Ulm, Germany
- *Correspondence: Thomas Datzmann,
| | - David Alexander Christian Messerer
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
- Klinik für Anästhesiologie und Intensivmedizin, Universitätsklinikum Ulm, Ulm, Germany
- Transfusionsmedizinische und Hämostaseologische Abteilung, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Franziska Münz
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
- Klinik für Anästhesiologie und Intensivmedizin, Universitätsklinikum Ulm, Ulm, Germany
| | - Andrea Hoffmann
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
| | - Michael Gröger
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
| | - René Mathieu
- Klinik fuür Neurochirurgie, Bundeswehrkrankenhaus Ulm, Ulm, Germany
| | - Simon Mayer
- Klinik fuür Neurochirurgie, Bundeswehrkrankenhaus Ulm, Ulm, Germany
| | - Holger Gässler
- Klinik fuür Anästhesiologie, Intensivmedizin, Notfallmedizin und Schmerztherapie, Bundeswehrkrankenhaus Ulm, Ulm, Germany
| | - Fabian Zink
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
| | - Oscar McCook
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
| | - Tamara Merz
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
- Klinik für Anästhesiologie und Intensivmedizin, Universitätsklinikum Ulm, Ulm, Germany
| | - Angelika Scheuerle
- Sektion Neuropathologie, Institut für Pathologie, Universitätsklinikum Ulm, Ulm, Germany
| | - Eva-Maria Wolfschmitt
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
| | - Timo Thebrath
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
| | - Stefan Zuech
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
| | - Enrico Calzia
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
| | - Pierre Asfar
- Département de Médecine Intensive – Réanimation et Médecine Hyperbare, Centre Hospitalier Universitaire, Angers, France
| | - Peter Radermacher
- Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Universitätsklinikum Ulm, Ulm, Germany
| | - Thomas Kapapa
- Klinik für Neurochirurgie, Universitätsklinikum Ulm, Ulm, Germany
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Lång M, Skrifvars MB, Siironen J, Tanskanen P, Ala-Peijari M, Koivisto T, Djafarzadeh S, Bendel S. A pilot study of hyperoxemia on neurological injury, inflammation and oxidative stress. Acta Anaesthesiol Scand 2018; 62:801-810. [PMID: 29464691 DOI: 10.1111/aas.13093] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 01/11/2018] [Accepted: 01/19/2018] [Indexed: 12/25/2022]
Abstract
BACKGROUND Normobaric hyperoxia is used to alleviate secondary brain ischaemia in patients with traumatic brain injury (TBI), but clinical evidence is limited and hyperoxia may cause adverse events. METHODS An open label, randomised controlled pilot study comparing blood concentrations of reactive oxygen species (ROS), interleukin 6 (IL-6) and neuron-specific enolase (NSE) between two different fractions of inspired oxygen in severe TBI patients on mechanical ventilation. RESULTS We enrolled 27 patients in the Fi O2 0.40 group and 38 in the Fi O2 0.70 group; 19 and 23 patients, respectively, completed biochemical analyses. In baseline, there were no differences between Fi O2 0.40 and Fi O2 0.70 groups, respectively, in ROS (64.8 nM [22.6-102.1] vs. 64.9 nM [26.8-96.3], P = 0.80), IL-6 (group 92.4 pg/ml [52.9-171.6] vs. 94.3 pg/ml [54.8-133.1], P = 0.52) or NSE (21.04 ug/l [14.0-30.7] vs. 17.8 ug/l [14.1-23.9], P = 0.35). ROS levels did not differ at Day 1 (24.2 nM [20.6-33.5] vs. 29.2 nM [22.7-69.2], P = 0.10) or at Day 2 (25.4 nM [21.7-37.4] vs. 47.3 nM [34.4-126.1], P = 0.95). IL-6 concentrations did not differ at Day 1 (112.7 pg/ml [65.9-168.9) vs. 83.9 pg/ml [51.8-144.3], P = 0.41) or at Day 3 (55.0 pg/ml [34.2-115.6] vs. 49.3 pg/ml [34.4-126.1], P = 0.95). NSE levels did not differ at Day 1 (15.9 ug/l [9.0-24.3] vs. 15.3 ug/l [12.2-26.3], P = 0.62). There were no differences between groups in the incidence of pulmonary complications. CONCLUSION Higher fraction of inspired oxygen did not increase blood concentrations of markers of oxidative stress, inflammation or neurological injury or the incidence of pulmonary complications in severe TBI patients on mechanical ventilation.
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Affiliation(s)
- M. Lång
- Department of Intensive Care Medicine; Kuopio University Hospital; Kys Finland
| | - M. B. Skrifvars
- Department of Anaesthesiology, Intensive Care and Pain Medicine; Helsinki University and Helsinki University Hospital; Helsinki Finland
| | - J. Siironen
- Department of Neurosurgery; Helsinki University and Helsinki University Hospital; Helsinki Finland
| | - P. Tanskanen
- Department of Anaesthesiology, Intensive Care and Pain Medicine; Helsinki University and Helsinki University Hospital; Helsinki Finland
| | - M. Ala-Peijari
- Department of Intensive Care Medicine; Tampere University Hospital; Tampere Finland
| | - T. Koivisto
- Department of Neurosurgery; Kuopio University Hospital; Kys Finland
| | - S. Djafarzadeh
- Department of Intensive Care Medicine, Inselspital; Bern University Hospital; Bern Switzerland
| | - S. Bendel
- Department of Intensive Care Medicine; Kuopio University Hospital; Kys Finland
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Veenith TV, Carter EL, Grossac J, Newcombe VFJ, Outtrim JG, Nallapareddy S, Lupson V, Correia MM, Mada MM, Williams GB, Menon DK, Coles JP. Normobaric hyperoxia does not improve derangements in diffusion tensor imaging found distant from visible contusions following acute traumatic brain injury. Sci Rep 2017; 7:12419. [PMID: 28963497 PMCID: PMC5622132 DOI: 10.1038/s41598-017-12590-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 09/01/2017] [Indexed: 11/09/2022] Open
Abstract
We have previously shown that normobaric hyperoxia may benefit peri-lesional brain and white matter following traumatic brain injury (TBI). This study examined the impact of brief exposure to hyperoxia using diffusion tensor imaging (DTI) to identify axonal injury distant from contusions. Fourteen patients with acute moderate/severe TBI underwent baseline DTI and following one hour of 80% oxygen. Thirty-two controls underwent DTI, with 6 undergoing imaging following graded exposure to oxygen. Visible lesions were excluded and data compared with controls. We used the 99% prediction interval (PI) for zero change from historical control reproducibility measurements to demonstrate significant change following hyperoxia. Following hyperoxia DTI was unchanged in controls. In patients following hyperoxia, mean diffusivity (MD) was unchanged despite baseline values lower than controls (p < 0.05), and fractional anisotropy (FA) was lower within the left uncinate fasciculus, right caudate and occipital regions (p < 0.05). 16% of white and 14% of mixed cortical and grey matter patient regions showed FA decreases greater than the 99% PI for zero change. The mechanistic basis for some findings are unclear, but suggest that a short period of normobaric hyperoxia is not beneficial in this context. Confirmation following a longer period of hyperoxia is required.
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Affiliation(s)
- Tonny V Veenith
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, Cambridgeshire, CB2 0QQ, UK
- Department of Critical Care Medicine, University Hospital of Birmingham NHS Trust, Queen Elizabeth Medical Centre, Birmingham, B15 2TH, UK
| | - Eleanor L Carter
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, Cambridgeshire, CB2 0QQ, UK
| | - Julia Grossac
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, Cambridgeshire, CB2 0QQ, UK
- Anesthesiology and Critical Care Department, University Hospital of Toulouse, 31000, Toulouse, France
| | - Virginia F J Newcombe
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, Cambridgeshire, CB2 0QQ, UK
| | - Joanne G Outtrim
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, Cambridgeshire, CB2 0QQ, UK
| | - Sri Nallapareddy
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, Cambridgeshire, CB2 0QQ, UK
| | - Victoria Lupson
- Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK
| | - Marta M Correia
- Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK
| | - Marius M Mada
- Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK
| | - Guy B Williams
- Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK
| | - David K Menon
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, Cambridgeshire, CB2 0QQ, UK
| | - Jonathan P Coles
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, Cambridgeshire, CB2 0QQ, UK.
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7
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Aeromedical evacuation-relevant hypobaria worsens axonal and neurologic injury in rats after underbody blast-induced hyperacceleration. J Trauma Acute Care Surg 2017; 83:S35-S42. [PMID: 28452879 DOI: 10.1097/ta.0000000000001478] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Occupants of military vehicles targeted by explosive devices often suffer from traumatic brain injury (TBI) and are typically transported by the aeromedical evacuation (AE) system to a military medical center within a few days. This study tested the hypothesis that exposure of rats to AE-relevant hypobaria worsens cerebral axonal injury and neurologic impairment caused by underbody blasts. METHODS Anesthetized adult male rats were secured within cylinders attached to a metal plate, simulating the hull of an armored vehicle. An explosive located under the plate was detonated, resulting in a peak vertical acceleration force on the plate and occupant rats of 100G. Rats remained under normobaria or were exposed to hypobaria equal to 8,000 feet in an altitude chamber for 6 hours, starting at 6 hours to 6 days after blast. At 7 days, rats were tested for vestibulomotor function using the balance beam walking task and euthanized by perfusion. The brains were then analyzed for axonal fiber injury. RESULTS The number of internal capsule silver-stained axonal fibers was greater in animals exposed to 100G blast than in shams. Animals exposed to hypobaria starting at 6 hours to 6 days after blast exhibited more silver-stained fibers than those not exposed to hypobaria. Rats exposed to 100% oxygen (O2) during hypobaria at 24 hours postblast displayed greater silver staining and more balance beam foot-faults, in comparison with rats exposed to hypobaria under 21% O2. CONCLUSION Exposure of rats to blast-induced acceleration of 100G increases cerebral axonal injury, which is significantly exacerbated by exposure to hypobaria as early as 6 hours and as late as 6 days postblast. Rats exposed to underbody blasts and then to hypobaria under 100% O2 exhibit increased axonal damage and impaired motor function compared to those subjected to blast and hypobaria under 21% O2. These findings raise concern about the effects of AE-related hypobaria on TBI victims, the timing of AE after TBI, and whether these effects can be mitigated by supplemental oxygen.
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9
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Hyperoxic resuscitation improves survival but worsens neurologic outcome in a rat polytrauma model of traumatic brain injury plus hemorrhagic shock. J Trauma Acute Care Surg 2016; 79:S101-9. [PMID: 26406421 DOI: 10.1097/ta.0000000000000742] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Many traumatic brain injury (TBI) patients experience additional injuries, including those that result in hemorrhagic shock (HS). Interactions between HS and TBI can include reduced brain O2 delivery, resulting in partial cerebral ischemia and worse neurologic outcome. This study tested the hypothesis that inspiration of 100% O2 during resuscitation following TBI and HS improves survival, reduces brain lesion volume, and improves neurologic outcome compared with resuscitation in the absence of supplemental O2. METHODS The adult male rat polytrauma model consisted of controlled cortical impact-induced TBI followed by 30 minutes of HS (mean arterial pressure, 35-40 mm Hg) induced by blood withdrawal. The HS phase was followed by a 1-hour "prehospital" Hextend fluid resuscitation phase and then a 1-hour "hospital phase" when shed blood was reinfused. Rats were randomized on the day of surgery to three groups with 10 per group: sham, polytrauma normoxic, and polytrauma hyperoxic. Normoxic animals inspired room air, and hyperoxic animals inspired 100% O2 during both resuscitation phases. Neurobehavioral tests were conducted weekly until the rats were perfused with fixative at 30 days after injury. Brain sections were stained with Fluoro Jade B and used for quantification of contusion, penumbral, and healthy cortical volumes. RESULTS Survival was greater following hyperoxic compared with normoxic resuscitation. Composite neuroscores obtained at 2 weeks to 4 weeks following hyperoxic resuscitation were lower than those of shams. Balance beam foot faults measured at 2 weeks after injury were greater following hyperoxic resuscitation compared with normoxic resuscitation and those of shams. There was no significant difference in cerebrocortical pathology between the normoxic and hyperoxic polytrauma groups. CONCLUSION The survival of rats following controlled cortical impact plus HS was greater following hyperoxic resuscitation. In contrast, neurologic outcomes were better following normoxic resuscitation.
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10
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Fidan E, Lewis J, Kline AE, Garman RH, Alexander H, Cheng JP, Bondi CO, Clark RSB, Dezfulian C, Kochanek PM, Kagan VE, Bayır H. Repetitive Mild Traumatic Brain Injury in the Developing Brain: Effects on Long-Term Functional Outcome and Neuropathology. J Neurotrauma 2015. [PMID: 26214116 DOI: 10.1089/neu.2015.3958] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Although accumulating evidence suggests that repetitive mild TBI (rmTBI) may cause long-term cognitive dysfunction in adults, whether rmTBI causes similar deficits in the immature brain is unknown. Here we used an experimental model of rmTBI in the immature brain to answer this question. Post-natal day (PND) 18 rats were subjected to either one, two, or three mild TBIs (mTBI) or an equivalent number of sham insults 24 h apart. After one or two mTBIs or sham insults, histology was evaluated at 7 days. After three mTBIs or sham insults, motor (d1-5), cognitive (d11-92), and histological (d21-92) outcome was evaluated. At 7 days, silver degeneration staining revealed axonal argyrophilia in the external capsule and corpus callosum after a single mTBI, with a second impact increasing axonal injury. Iba-1 immunohistochemistry showed amoeboid shaped microglia within the amygdalae bilaterally after mTBI. After three mTBI, there were no differences in beam balance, Morris water maze, and elevated plus maze performance versus sham. The rmTBI rats, however, showed impairment in novel object recognition and fear conditioning. Axonal silver staining was observed only in the external capsule on d21. Iba-1 staining did not reveal activated microglia on d21 or d92. In conclusion, mTBI results in traumatic axonal injury and microglial activation in the immature brain with repeated impact exacerbating axonal injury. The rmTBI in the immature brain leads to long-term associative learning deficit in adulthood. Defining the mechanisms damage from rmTBI in the developing brain could be vital for identification of therapies for children.
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Affiliation(s)
- Emin Fidan
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Jesse Lewis
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Anthony E Kline
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania.,2 Department of Physical Medicine and Rehabilitation, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Robert H Garman
- 4 Consultants in Veterinary Pathology, Inc. , Murrysville, Pennsylvania
| | - Henry Alexander
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Jeffrey P Cheng
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania.,2 Department of Physical Medicine and Rehabilitation, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Corina O Bondi
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania.,2 Department of Physical Medicine and Rehabilitation, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Robert S B Clark
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania.,5 Children's Hospital of Pittsburgh , Pittsburgh, Pennsylvania
| | - Cameron Dezfulian
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania.,5 Children's Hospital of Pittsburgh , Pittsburgh, Pennsylvania
| | - Patrick M Kochanek
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania.,5 Children's Hospital of Pittsburgh , Pittsburgh, Pennsylvania
| | - Valerian E Kagan
- 3 Center for Free Radical and Antioxidant Health, Department of Environmental and Occupational Health, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Hülya Bayır
- 1 Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania.,3 Center for Free Radical and Antioxidant Health, Department of Environmental and Occupational Health, University of Pittsburgh , Pittsburgh, Pennsylvania.,5 Children's Hospital of Pittsburgh , Pittsburgh, Pennsylvania
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11
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Veenith TV, Carter EL, Grossac J, Newcombe VF, Outtrim JG, Nallapareddy S, Lupson V, Correia MM, Mada MM, Williams GB, Menon DK, Coles JP. Use of diffusion tensor imaging to assess the impact of normobaric hyperoxia within at-risk pericontusional tissue after traumatic brain injury. J Cereb Blood Flow Metab 2014; 34:1622-7. [PMID: 25005875 PMCID: PMC4269721 DOI: 10.1038/jcbfm.2014.123] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 05/15/2014] [Accepted: 06/09/2014] [Indexed: 12/31/2022]
Abstract
Ischemia and metabolic dysfunction remain important causes of neuronal loss after head injury, and we have shown that normobaric hyperoxia may rescue such metabolic compromise. This study examines the impact of hyperoxia within injured brain using diffusion tensor imaging (DTI). Fourteen patients underwent DTI at baseline and after 1 hour of 80% oxygen. Using the apparent diffusion coefficient (ADC) we assessed the impact of hyperoxia within contusions and a 1 cm border zone of normal appearing pericontusion, and within a rim of perilesional reduced ADC consistent with cytotoxic edema and metabolic compromise. Seven healthy volunteers underwent imaging at 21%, 60%, and 100% oxygen. In volunteers there was no ADC change with hyperoxia, and contusion and pericontusion ADC values were higher than volunteers (P<0.01). There was no ADC change after hyperoxia within contusion, but an increase within pericontusion (P<0.05). We identified a rim of perilesional cytotoxic edema in 13 patients, and hyperoxia resulted in an ADC increase towards normal (P=0.02). We demonstrate that hyperoxia may result in benefit within the perilesional rim of cytotoxic edema. Future studies should address whether a longer period of hyperoxia has a favorable impact on the evolution of tissue injury.
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Affiliation(s)
- Tonny V Veenith
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Eleanor L Carter
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Julia Grossac
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Virginia F Newcombe
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Joanne G Outtrim
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Sridhar Nallapareddy
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Victoria Lupson
- Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Marta M Correia
- Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Marius M Mada
- Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Guy B Williams
- Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - David K Menon
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
| | - Jonathan P Coles
- Division of Anaesthesia, University of Cambridge, Addenbrooke's Hospital, Cambridge, Cambridgeshire, UK
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12
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Algattas H, Huang JH. Traumatic Brain Injury pathophysiology and treatments: early, intermediate, and late phases post-injury. Int J Mol Sci 2013; 15:309-41. [PMID: 24381049 PMCID: PMC3907812 DOI: 10.3390/ijms15010309] [Citation(s) in RCA: 158] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Revised: 12/02/2013] [Accepted: 12/20/2013] [Indexed: 12/25/2022] Open
Abstract
Traumatic Brain Injury (TBI) affects a large proportion and extensive array of individuals in the population. While precise pathological mechanisms are lacking, the growing base of knowledge concerning TBI has put increased emphasis on its understanding and treatment. Most treatments of TBI are aimed at ameliorating secondary insults arising from the injury; these insults can be characterized with respect to time post-injury, including early, intermediate, and late pathological changes. Early pathological responses are due to energy depletion and cell death secondary to excitotoxicity, the intermediate phase is characterized by neuroinflammation and the late stage by increased susceptibility to seizures and epilepsy. Current treatments of TBI have been tailored to these distinct pathological stages with some overlap. Many prophylactic, pharmacologic, and surgical treatments are used post-TBI to halt the progression of these pathologic reactions. In the present review, we discuss the mechanisms of the pathological hallmarks of TBI and both current and novel treatments which target the respective pathways.
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Affiliation(s)
- Hanna Algattas
- School of Medicine and Dentistry, University of Rochester Medical Center, 601 Elmwood Ave, Box 441, Rochester, NY 14642, USA.
| | - Jason H Huang
- School of Medicine and Dentistry, University of Rochester Medical Center, 601 Elmwood Ave, Box 441, Rochester, NY 14642, USA.
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13
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Balan IS, Saladino AJ, Aarabi B, Castellani RJ, Wade C, Stein DM, Eisenberg HM, Chen HH, Fiskum G. Cellular alterations in human traumatic brain injury: changes in mitochondrial morphology reflect regional levels of injury severity. J Neurotrauma 2013; 30:367-81. [PMID: 23131111 DOI: 10.1089/neu.2012.2339] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Mitochondrial dysfunction may be central to the pathophysiology of traumatic brain injury (TBI) and often can be recognized cytologically by changes in mitochondrial ultrastructure. This study is the first to broadly characterize and quantify mitochondrial morphologic alterations in surgically resected human TBI tissues from three contiguous cortical injury zones. These zones were designated as injury center (Near), periphery (Far), and Penumbra. Tissues from 22 patients with TBI with varying degrees of damage and time intervals from TBI to surgical tissue collection within the first week post-injury were rapidly fixed in the surgical suite and processed for electron microscopy. A large number of mitochondrial structural patterns were identified and divided into four survival categories: normal, normal reactive, reactive degenerating, and end-stage degenerating profiles. A tissue sample acquired at 38 hours post-injury was selected for detailed mitochondrial quantification, because it best exhibited the wide variation in cellular and mitochondrial changes consistently noted in all the other cases. The distribution of mitochondrial morphologic phenotypes varied significantly between the three injury zones and when compared with control cortical tissue obtained from an epilepsy lobectomy. This study is unique in its comparative quantification of the mitochondrial ultrastructural alterations at progressive distances from the center of injury in surviving TBI patients and in relation to control human cortex. These quantitative observations may be useful in guiding the translation of mitochondrial-based neuroprotective interventions to clinical implementation.
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Affiliation(s)
- Irina S Balan
- Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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14
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Beynon C, Kiening KL, Orakcioglu B, Unterberg AW, Sakowitz OW. Brain tissue oxygen monitoring and hyperoxic treatment in patients with traumatic brain injury. J Neurotrauma 2012; 29:2109-23. [PMID: 22616852 DOI: 10.1089/neu.2012.2365] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Cerebral ischemia is a well-recognized contributor to high morbidity and mortality after traumatic brain injury (TBI). Standard of care treatment aims to maintain a sufficient oxygen supply to the brain by avoiding increased intracranial pressure (ICP) and ensuring a sufficient cerebral perfusion pressure (CPP). Devices allowing direct assessment of brain tissue oxygenation have showed promising results in clinical studies, and their use was implemented in the Brain Trauma Foundation Guidelines for the treatment of TBI patients in 2007. Results of several studies suggest that a brain tissue oxygen-directed therapy guided by these monitors may contribute to reduced mortality and improved outcome of TBI patients. Whether increasing the oxygen supply to supraphysiological levels has beneficial or detrimental effects on TBI patients has been a matter of debate for decades. The results of trials of hyperbaric oxygenation (HBO) have failed to show a benefit, but renewed interest in normobaric hyperoxia (NBO) in the treatment of TBI patients has emerged in recent years. With the increased availability of advanced neuromonitoring devices such as brain tissue oxygen monitors, it was shown that some patients might benefit from this therapeutic approach. In this article, we review the pathophysiological rationale and technical modalities of brain tissue oxygen monitors, as well as its use in studies of brain tissue oxygen-directed therapy. Furthermore, we analyze hyperoxia as a treatment option in TBI patients, summarize the results of clinical trials, and give insights into the recent findings of hyperoxic effects on cerebral metabolism after TBI.
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Affiliation(s)
- Christopher Beynon
- Department of Neurosurgery, Heidelberg University Hospital, Heidelberg, Germany.
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15
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Günther M, Al Nimer F, Gahm C, Piehl F, Mathiesen T. iNOS-mediated secondary inflammatory response differs between rat strains following experimental brain contusion. Acta Neurochir (Wien) 2012; 154:689-97. [PMID: 22362050 DOI: 10.1007/s00701-012-1297-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 01/30/2012] [Indexed: 12/23/2022]
Abstract
BACKGROUND Nitric oxide is a key mediator of post-traumatic inflammation in the brain. We examined the expressions of iNOS, nNOS, and eNOS in inbred DA and PVGa rat strains where DA is susceptible to autoimmune neuroinflammation and PVGa-resistant. METHODS Parietal contusions using a weight drop model were produced in five rats per genotype. After 24 h, the brains were removed and analyzed using a range of immunohistochemical methods. RESULTS PVGa presented significantly increased iNOS expression in infiltrating inflammatory cells in the perilesional area compared to DA (p < 0.05). The amount of w3/13-positive infiltrating inflammatory cells did not differ between strains. eNOS and nNOS expression did not differ between strains. iNOS-positive cells coexpressed neuronal (NeuN), macrophage (ED-1), and leucocyte (w3/13) markers. MnSOD was significantly increased in PVGa (p < 0.05). 3-Nitrotyrosine, a measure of peroxynitrite levels, and fluoro-jade stained neuronal degeneration, did not differ between strains. CONCLUSIONS Two inbred rat strains with genetically determined differences in susceptibility to develop autoimmune disease displayed different levels of the inflammatory and anti-inflammatory mediators iNOS and MnSOD, indicating genetic regulation. Interestingly, the increased levels of iNOS did not lead to elevated expression of the neuronal cell-death marker fluoro-jade. The increased iNOS expression was correlated with increased expression of superoxide scavenger MnSOD. Excessive peroxynitrite formation was probably prevented by limitation of available superoxide. Subsequently, the higher expression of potentially deleterious iNOS in PVGa did not result in increased neuronal death.
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Affiliation(s)
- Mattias Günther
- Department of Clinical Neuroscience, Section of Neurosurgery and Neuroimmunology, Karolinska Institutet, Stockholm, Sweden.
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16
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Francony G, Bouzat P, Picard J, Fevre MC, Gay S, Payen JF. [Normobaric hyperoxia therapy for patients with traumatic brain injury]. ANNALES FRANCAISES D'ANESTHESIE ET DE REANIMATION 2012; 31:224-227. [PMID: 22305404 DOI: 10.1016/j.annfar.2011.11.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2011] [Accepted: 11/09/2011] [Indexed: 05/31/2023]
Abstract
Cerebral ischaemia plays a major role in the outcome of brain-injured patients. Because brain oxygenation can be assessed at bedside using intra-parenchymal devices, there has been a growing interest about whether therapeutic hyperoxia could be beneficial for severely head-injured patients. Normobaric hyperoxia increases brain oxygenation and may improve glucose-lactate metabolism in brain regions at risk for ischaemia. However, benefits of normobaric hyperoxia on neurological outcome are not established yet, that hinders the systematic use of therapeutic hyperoxia in head-injured patients. This therapeutic option might be proposed when brain ischemia persists despite the optimization of cerebral blood flow and arterial oxygen blood content.
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Affiliation(s)
- G Francony
- Pôle anesthésie-réanimation, hôpital Michallon, BP 217, 38043 Grenoble cedex 09, France
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17
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Zaghloul N, Nasim M, Patel H, Codipilly C, Marambaud P, Dewey S, Schiffer WK, Ahmed M. Overexpression of extracellular superoxide dismutase has a protective role against hyperoxia-induced brain injury in neonatal mice. FEBS J 2012; 279:871-81. [PMID: 22240000 DOI: 10.1111/j.1742-4658.2012.08478.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
There is increasing evidence that hyperoxia, particularly at the time of birth, may result in neurological injury, in particular to the susceptible vasculature of these tissues. This study was aimed at determining whether overexpression of extracellular superoxide dismutase (EC-SOD) is protective against brain injury induced by hyperoxia. Transgenic (TG) mice (with an extra copy of the human extracellular superoxide dismutase gene) and wild-type (WT) neonate mice were exposed to hyperoxia (95% of F(i) o(2) ) for 7 days after birth versus the control group in room air. Brain positron emission tomography (PET) scanning with fludeoxyglucose (FDG) isotope uptake was performed after exposure. To assess apoptosis induced by hyperoxia exposure, caspase 3 ELISA and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were performed. Quantitative western blot for the following inflammatory markers was performed: glial fibrillary acidic protein, ionized calcium-binding adaptor molecule 1, macrophage-inhibiting factor, and phospho-AMP-activated protein kinase. PET scanning with FDG isotope uptake showed significantly higher uptake in the WT hyperoxia neonate brain group (0.14 ± 0.03) than in both the TG group (0.09 ± 0.01) and the control group (0.08 ± 0.02) (P< 0.05). Histopathological investigation showed more apoptosis and dead neurons in hippocampus and cerebellum brain sections of WT neonate mice after exposure to hyperoxia than in TG mice; this finding was also confirmed by TUNEL staining. The caspase 3 assay confirmed the finding of more apoptosis in WT hyperoxia neonates (0.814 ± 0.112) than in the TG hyperoxic group (0.579 ± 0.144) (P < 0.05); this finding was also confirmed by TUNEL staining. Quantitative western blotting for the inflammatory and metabolic markers showed significantly higher expression in the WT group than in the TG and control groups. Thus, overexpression of EC-SOD in the neonate brain offers significant protection against hyperoxia-induced brain damage.
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Affiliation(s)
- Nahla Zaghloul
- Department of Pediatrics, Cohen Children's Medical Center, NS-LIJ, Manhasset, NY 11030, USA
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18
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Navarro JC, Pillai S, Cherian L, Garcia R, Grill RJ, Robertson CS. Histopathological and behavioral effects of immediate and delayed hemorrhagic shock after mild traumatic brain injury in rats. J Neurotrauma 2012; 29:322-34. [PMID: 22077317 DOI: 10.1089/neu.2011.1979] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The purpose of this study was to investigate the increased susceptibility of the brain, after a controlled mild cortical impact injury, to a secondary ischemic insult. The effects of the duration and the timing of the secondary insult after the initial cortical injury were studied. Rats anesthetized with isoflurane underwent a 3 m/sec, 2.5-mm deformation cortical impact injury followed by hypotension to 40 mm Hg induced by withdrawing blood from a femoral vein. The duration of hypotension was varied from 40 to 60 min. The timing of 60 min of hypotension was varied from immediately post-injury to 7 days after the injury. Outcome was assessed by behavioral tasks and histological examination at 2 weeks post-injury. A separate group of animals underwent measurement of the acute physiology including mean blood pressure (MAP), intracranial pressure (ICP), and cerebral blood flow (CBF) using a laser Doppler technique. Increasing durations of hypotension resulted in marked expansion of the contusion, from 6.5±1.8 mm³ with sham hypotension to 27.1±3.9 mm³ with 60 min of hypotension. This worsening of the contusion was found only when then hypotension occurred immediately after injury or at 1 h after injury. CA3 neuron loss followed a similar pattern, but the injury group differences were not significant. Motor tasks, including beam balance and beam walking, were significantly worse following 50 and 60 min of hypotension. Performance on the Morris water maze task was also significantly related to the injury group. Studies of the acute cerebral hemodynamics demonstrated that CBF was significantly more impaired during hypotension in the animals that underwent the mild TBI compared to those that underwent sham TBI. The perfusion deficit was worst at the impact site, but also significant in the pericontusional brain. With 50 and 60 min of hypotension, CBF did not recover following resuscitation at the impact site, and recovered only transiently in the pericontusional brain. These results demonstrate that mild TBI, like more severe levels of TBI, can impair the brain's ability to maintain CBF during a period of hypotension, and result in a worse outcome.
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Mao H, Guan F, Han X, Yang KH. Strain-based regional traumatic brain injury intensity in controlled cortical impact: a systematic numerical analysis. J Neurotrauma 2011; 28:2263-76. [PMID: 21488718 DOI: 10.1089/neu.2010.1600] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Regional strain-based brain injury intensity during controlled cortical impact (CCI) was studied using a three-dimensional numerical rat brain model. A full factorial design of CCI computer experiments was performed using two typical impactor shapes (flat or hemispherical) at a fixed impact velocity of 4?m/s with various impact depths (1, 1.5, 1.6, 2, 2.5, 2.7, and 3?mm) and various impactor diameters (4, 5, 6, 8, and 9.5?mm). In total, 70 CCI cases were simulated numerically. Two injury assessment measures, the cumulative strain damage measure (CSDM), which accounts for the volume of brain tissue with elevated strains, and cumulative strain damage percentage measure (CSDPM), which is a strain-based estimate of the neuronal cell loss percentage, were used to evaluate the risk of brain injury. Results demonstrated positive nonlinear relationships between impact depth and these injury assessment measures in six regions of interest: ipsilateral cortex, ipsilateral corpus callosum, ipsilateral hippocampus, ipsilateral thalamus, cerebellum, and brainstem. However, the impactor diameter was not always positively correlated with regional tissue strains. For the flat impactor group, the 5?mm diameter impactor induced more tissue strain in the corpus callosum/hippocampus, and a smaller impactor induced more strain in the thalamus. For the hemispherical impactor group, a larger impactor tended to induce more tissue strain in subcortical regions, with the exception of the 6?mm diameter impactor. This study systematically predicts regional intensity of primary brain injury according to tissue strain distributions in the hope that strain distribution maps may become a common platform to compare CCI severities with different configurations.
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Affiliation(s)
- Haojie Mao
- Bioengineering Center, Wayne State University, Detroit, Michigan 48201, USA
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Wiktorowicz JE, Stafford S, Rea H, Urvil P, Soman K, Kurosky A, Perez-Polo JR, Savidge TC. Quantification of cysteinyl S-nitrosylation by fluorescence in unbiased proteomic studies. Biochemistry 2011; 50:5601-14. [PMID: 21615140 PMCID: PMC3133729 DOI: 10.1021/bi200008b] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cysteinyl S-nitrosylation has emerged as an important post-translational modification affecting protein function in health and disease. Great emphasis has been placed on global, unbiased quantification of S-nitrosylated proteins because of physiologic and oxidative stimuli. However, current strategies have been hampered by sample loss and altered protein electrophoretic mobility. Here, we describe a novel quantitative approach that uses accurate, sensitive fluorescence modification of cysteine S-nitrosylation that leaves electrophoretic mobility unaffected (SNOFlo) and introduce unique concepts for measuring changes in S-nitrosylation status relative to protein abundance. Its efficacy in defining the functional S-nitrosoproteome is demonstrated in two diverse biological applications: an in vivo rat hypoxia-ischemia/reperfusion model and antimicrobial S-nitrosoglutathione-driven transnitrosylation of an enteric microbial pathogen. The suitability of this approach for investigating endogenous S-nitrosylation is further demonstrated using Ingenuity Pathways analysis that identified nervous system and cellular development networks as the top two networks. Functional analysis of differentially S-nitrosylated proteins indicated their involvement in apoptosis, branching morphogenesis of axons, cortical neurons, and sympathetic neurites, neurogenesis, and calcium signaling. Major abundance changes were also observed for fibrillar proteins known to be stress-responsive in neurons and glia. Thus, both examples demonstrate the technique's power in confirming the widespread involvement of S-nitrosylation in hypoxia-ischemia/reperfusion injury and in antimicrobial host responses.
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Affiliation(s)
- John E Wiktorowicz
- Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch , Galveston, Texas 77555, USA.
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Ferrari DC, Nesic O, Perez-Polo JR. Perspectives on neonatal hypoxia/ischemia-induced edema formation. Neurochem Res 2010; 35:1957-65. [PMID: 21136160 DOI: 10.1007/s11064-010-0308-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2010] [Indexed: 11/30/2022]
Abstract
Neonatal hypoxia/ischemia (HI) is the most common cause of developmental neurological, cognitive and behavioral deficits in children, with hyperoxia (HHI) treatment being a clinical therapy for newborn resuscitation. Although cerebral edema is a common outcome after HI, the mechanisms leading to excessive fluid accumulation in the brain are poorly understood. Given the rigid nature of the bone-encased brain matter, knowledge of edema formation in the brain as a consequence of any injury, as well as the importance of water clearance mechanisms and water and ion homeostasis is important to our understanding of its detrimental effects. Knowledge of the pathological process underlying the appearance of dysfunctional outcomes after development of cerebral edema after neonatal HI in the developing brain and the molecular events triggered will allow a rational assessment of HHI therapy for neonatal HI and determine whether this treatment is beneficial or harmful to the developing infant.
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Reducing the duration of 100% oxygen ventilation in the early reperfusion period after cardiopulmonary resuscitation decreases striatal brain damage. Resuscitation 2010; 81:1698-703. [DOI: 10.1016/j.resuscitation.2010.06.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Revised: 06/18/2010] [Accepted: 06/30/2010] [Indexed: 11/23/2022]
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Survival and differentiation of neuroectodermal cells with stem cell properties at different oxygen levels. Exp Neurol 2010; 227:136-48. [PMID: 20969864 DOI: 10.1016/j.expneurol.2010.10.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 10/06/2010] [Accepted: 10/12/2010] [Indexed: 12/15/2022]
Abstract
Freeze-lesioned regions of the forebrain cortex provide adequate environment for growth of non-differentiated neural progenitors, but do not support their neuron formation. Reduced oxygen supply, among numerous factors, was suspected to impair neuronal cell fate commitment. In the present study, proliferation and differentiation of neural stem/progenitor cells were investigated at different oxygen levels both in vitro and in vivo. Low (1% atmospheric) oxygen supply did not affect the in vitro viability and proliferation of stem cells or the transcription of "stemness" genes but impaired the viability of committed neuronal progenitors and the expression of proneural and neuronal genes. Consequently, the rate of in vitro neuron formation was markedly reduced under hypoxic conditions. In vivo, neural stem/progenitor cells survived and proliferated in freeze-lesioned adult mouse forebrains, but did not develop into neurons. Hypoperfusion-caused hypoxia in lesioned cortices was partially corrected by hyperbaric oxygen treatment (HBOT). HBOT, while reduced the rate of cell proliferation at the lesion site, resulted in sporadic neuron formation from implanted neural stem cells. The data indicate that in hypoxic brain areas, neural stem cells survive and proliferate, but neural tissue-type differentiation can not proceed. Oxygenation renders the damaged brain areas more permissive for tissue-type differentiation and may help the integration of neural stem/progenitor cells.
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Ferrari DC, Nesic OB, Perez-Polo JR. Oxygen resuscitation does not ameliorate neonatal hypoxia/ischemia-induced cerebral edema. J Neurosci Res 2010; 88:2056-65. [PMID: 20143414 DOI: 10.1002/jnr.22358] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Neonatal hypoxia/ischemia (HI) is a common cause of cognitive and behavioral deficits in children with hyperoxia treatment (HHI) being the current therapy for newborn resuscitation. HI induces cerebral edema that is associated with poor neurological outcomes. Our objective was to characterize cerebral edema after HI and determine the consequences of HHI (40% or 100% O(2)). Dry weight analyses showed cerebral edema 1 to 21 days after HI in the ipsilateral cortex; and 3 to 21 days after HI in the contralateral cortex. Furthermore, HI increased blood-brain barrier (BBB) permeability 1 to 7 days after HI, leading to bilateral cortical vasogenic edema. HHI failed to prevent HI-induced increase in BBB permeability and edema development. At the molecular level, HI increased ipsilateral, but not contralateral, AQP4 cortical levels at 3 and up to 21 days after HI. HHI treatment did not further affect HI-induced changes in AQP4. In addition, we observed developmental increases of AQP4 accompanied by significant reduction in water content and increase permeability of the BBB. Our results suggest that the ipsilateral HI-induced increase in AQP4 may be beneficial and that its absence in the contralateral cortex may account for edema formation after HI. Finally, we showed that HI induced impaired motor coordination 21 days after the insult and HHI did not ameliorate this behavioral outcome. We conclude that HHI treatment is effective as a resuscitating therapy, but does not ameliorate HI-induced cerebral edema and impaired motor coordination.
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Affiliation(s)
- Diana Carolina Ferrari
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555-1072, USA
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Erythropoietin attenuates hyperoxia-induced oxidative stress in the developing rat brain. Brain Behav Immun 2010; 24:792-9. [PMID: 19729061 DOI: 10.1016/j.bbi.2009.08.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 08/27/2009] [Accepted: 08/27/2009] [Indexed: 11/23/2022] Open
Abstract
Oxygen toxicity contributes to the pathogenesis of adverse neurological outcome in survivors of preterm birth in clinical studies. In infant rodent brains, hyperoxia triggers widespread apoptotic neurodegeneration, induces pro-inflammatory cytokines and inhibits growth factor signaling cascades. Since a tissue-protective effect has been observed for recombinant erythropoietin (rEpo), we hypothesized that rEpo would influence hyperoxia-induced oxidative stress in the developing rat brain. The aim of this study was to investigate the level of glutathione (reduced and oxidized), lipid peroxidation and the expression of heme oxygenase-1 (HO-1) and acetylcholinesterase (AChE) after hyperoxia and rEpo treatment. Six-day-old Wistar rats were exposed to 80% oxygen for 2-48 h and received 20,000 IU/kg rEpo intraperitoneally (i.p.). Sex-matched littermates kept under room air and injected with normal saline or rEpo served as controls. Treatment with rEpo significantly reduced hyperoxia-induced upregulation of oxidized glutathione (GSSG) and malondialdehyde, a product of lipid breakdown, whereas reduced glutathione (GSH) was upregulated by rEpo. In parallel, hyperoxia-treated immature rat brains revealed rEpo-suppressible upregulation of synaptic AChE-S as well as of the stress-inducible AChE-R variant, together predicting rEpo-protected cholinergic signaling and restrained inflammatory reactions. Furthermore, treatment with rEpo induced upregulation of HO-1 on mRNA, protein and activity level in the developing rat brain. Our results suggest that rEpo generates its protective effect against oxygen toxicity by a reduction of diverse oxidative stress parameters and by limiting the stressor-inducible changes in both HO-1 and cholinergic functions.
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Robertson CL, Scafidi S, McKenna MC, Fiskum G. Mitochondrial mechanisms of cell death and neuroprotection in pediatric ischemic and traumatic brain injury. Exp Neurol 2009; 218:371-80. [PMID: 19427308 DOI: 10.1016/j.expneurol.2009.04.030] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2009] [Revised: 04/23/2009] [Accepted: 04/28/2009] [Indexed: 11/30/2022]
Abstract
There are several forms of acute pediatric brain injury, including neonatal asphyxia, pediatric cardiac arrest with global ischemia, and head trauma, that result in devastating, lifelong neurologic impairment. The only clinical intervention that appears neuroprotective is hypothermia initiated soon after the initial injury. Evidence indicates that oxidative stress, mitochondrial dysfunction, and impaired cerebral energy metabolism contribute to the brain cell death that is responsible for much of the poor neurologic outcome from these events. Recent results obtained from both in vitro and animal models of neuronal death in the immature brain point toward several molecular mechanisms that are either induced or promoted by oxidative modification of macromolecules, including consumption of cytosolic and mitochondrial NAD(+) by poly-ADP ribose polymerase, opening of the mitochondrial inner membrane permeability transition pore, and inactivation of key, rate-limiting metabolic enzymes, e.g., the pyruvate dehydrogenase complex. In addition, the relative abundance of pro-apoptotic proteins in immature brains and neurons, and particularly within their mitochondria, predisposes these cells to the intrinsic, mitochondrial pathway of apoptosis, mediated by Bax- or Bak-triggered release of proteins into the cytosol through the mitochondrial outer membrane. Based on these pathways of cell dysfunction and death, several approaches toward neuroprotection are being investigated that show promise toward clinical translation. These strategies include minimizing oxidative stress by avoiding unnecessary hyperoxia, promoting aerobic energy metabolism by repletion of NAD(+) and by providing alternative oxidative fuels, e.g., ketone bodies, directly interfering with apoptotic pathways at the mitochondrial level, and pharmacologic induction of antioxidant and anti-inflammatory gene expression.
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Affiliation(s)
- Courtney L Robertson
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, 21201, USA
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27
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D'Agostino DP, Olson JE, Dean JB. Acute hyperoxia increases lipid peroxidation and induces plasma membrane blebbing in human U87 glioblastoma cells. Neuroscience 2009; 159:1011-22. [PMID: 19356685 DOI: 10.1016/j.neuroscience.2009.01.062] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Revised: 01/26/2009] [Accepted: 01/27/2009] [Indexed: 11/28/2022]
Abstract
Atomic force microscopy (AFM), malondialdehyde (MDA) assays, and amperometric measurements of extracellular hydrogen peroxide (H(2)O(2)) were used to test the hypothesis that graded hyperoxia induces measurable nanoscopic changes in membrane ultrastructure and membrane lipid peroxidation (MLP) in cultured U87 human glioma cells. U87 cells were exposed to 0.20 atmospheres absolute (ATA) O(2), normobaric hyperoxia (0.95 ATA O(2)) or hyperbaric hyperoxia (HBO(2), 3.25 ATA O(2)) for 60 min. H(2)O(2) (0.2 or 2 mM; 60 min) was used as a positive control for MLP. Cells were fixed with 2% glutaraldehyde immediately after treatment and scanned with AFM in air or fluid. Surface topography revealed ultrastructural changes such as membrane blebbing in cells treated with hyperoxia and H(2)O(2). Average membrane roughness (R(a)) of individual cells from each group (n=35 to 45 cells/group) was quantified to assess ultrastructural changes from oxidative stress. The R(a) of the plasma membrane was 34+/-3, 57+/-3 and 63+/-5 nm in 0.20 ATA O(2), 0.95 ATA O(2) and HBO(2), respectively. R(a) was 56+/-7 and 138+/-14 nm in 0.2 and 2 mM H(2)O(2). Similarly, levels of MDA were significantly elevated in cultures treated with hyperoxia and H(2)O(2) and correlated with O(2)-induced membrane blebbing (r(2)=0.93). Coapplication of antioxidant, Trolox-C (150 microM), significantly reduced membrane R(a) and MDA levels during hyperoxia. Hyperoxia-induced H(2)O(2) production increased 189%+/-5% (0.95 ATA O(2)) and 236%+/-5% (4 ATA O(2)) above control (0.20 ATA O(2)). We conclude that MLP and membrane blebbing increase with increasing O(2) concentration. We hypothesize that membrane blebbing is an ultrastructural correlate of MLP resulting from hyperoxia. Furthermore, AFM is a powerful technique for resolving nanoscopic changes in the plasma membrane that result from oxidative damage.
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Affiliation(s)
- D P D'Agostino
- Department of Molecular Pharmacology and Physiology, Hyperbaric Biomedical Research Laboratory, College of Medicine, MDC 8, University of South Florida, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
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