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Chen J, Xu S, Lee H, Wu L, He X, Zhao W, Zhang M, Ma Y, Ding Y, Fu Y, Wu C, Li M, Jiang M, Cheng H, Li S, Ma T, Ji X, Wu D. Hypothermic neuroprotection by targeted cold autologous blood transfusion in a non-human primate stroke model. Sci Bull (Beijing) 2023:S2095-9273(23)00392-4. [PMID: 37391345 DOI: 10.1016/j.scib.2023.06.017] [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: 03/02/2023] [Revised: 05/06/2023] [Accepted: 06/12/2023] [Indexed: 07/02/2023]
Abstract
Over decades, nearly all attempts to translate the benefits of therapeutic hypothermia in stroke models of lower-order species to stroke patients have failed. Potentially overlooked reasons may be biological gaps between different species and the mismatched initiation of therapeutic hypothermia in translational studies. Here, we introduce a novel strategy of selective therapeutic hypothermia in a non-human primate ischemia-reperfusion model, in which autologous blood was cooled ex vivo and the cool blood transfusion was administered at the middle cerebral artery just after the onset of reperfusion. Cold autologous blood cooled the targeted brain rapidly to below 34 °C while the rectal temperature remained around 36 °C with the assistance of a heat blanket during a 2-h hypothermic process. Therapeutic hypothermia or extracorporeal-circulation related complications were not observed. Cold autologous blood treatment reduced infarct sizes, preserved white matter integrity, and improved functional outcomes. Together, our results suggest that therapeutic hypothermia, induced by cold autologous blood transfusion, was achieved in a feasible, swift, and safe way in a non-human primate model of stroke. More importantly, this novel hypothermic approach conferred neuroprotection in a clinically relevant model of ischemic stroke due to reduced brain damage and improved neurofunction. This study reveals an underappreciated potential for this novel hypothermic modality for acute ischemic stroke in the era of effective reperfusion.
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Affiliation(s)
- Jian Chen
- Department of Neurosurgery, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China
| | - Shuaili Xu
- China-America Institute of Neuroscience, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China
| | - Hangil Lee
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit MI 46801, USA
| | - Longfei Wu
- Department of Neurology, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China
| | - Xiaoduo He
- China-America Institute of Neuroscience, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China
| | - Wenbo Zhao
- Department of Neurology, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China
| | - Mo Zhang
- Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Yanhui Ma
- Department of Anesthesiology, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China
| | - Yuchuan Ding
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit MI 46801, USA
| | - Yongjuan Fu
- Department of Pathology, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China
| | - Chuanjie Wu
- Department of Neurology, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China
| | - Ming Li
- Department of Neurosurgery, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China; Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Beijing 100053, China
| | - Miuwen Jiang
- Interdisciplinary Innovation Institute of Medicine and Engineering, Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China
| | - Huakun Cheng
- Department of Neurosurgery, Heilongjiang Provincial Hospital, Harbin 1500036, China
| | - Shengli Li
- Department of Laboratory Animal Science, Capital Medical University, Beijing 100069, China
| | - Ting Ma
- Department of Anesthesiology, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China.
| | - Xunming Ji
- Department of Neurosurgery, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China; Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Beijing 100053, China; Interdisciplinary Innovation Institute of Medicine and Engineering, Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China.
| | - Di Wu
- China-America Institute of Neuroscience, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing 100053, China.
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Xu S, Ji X, Li M, Wu D. Expedited brain cooling: Persistent temperature management from first aid to interhospital treatment. J Cereb Blood Flow Metab 2023; 43:319-321. [PMID: 36127836 PMCID: PMC9903226 DOI: 10.1177/0271678x221127088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/23/2022] [Accepted: 08/29/2022] [Indexed: 01/24/2023]
Abstract
Selective brain cooling is a promising technique for improving outcomes in ischemic stroke in the area of reperfusion. A recent study described the efficacy of a new method of selective brain cooling via active conductive head cooling. This is a major step forward in the administration of hypothermic treatment during pre-hospital transfer. However, to enhance the benefits of selective therapeutic cooling, a more comprehensive strategy preventing delay in hypothermic induction and increasing the accuracy of selectivity in the brain should be considered to mitigate the side effects related to therapeutic hypothermia.
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Affiliation(s)
- Shuaili Xu
- Department of Neurology and China-America Institute of Neuroscience, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
| | - Xunming Ji
- Department of Neurology and China-America Institute of Neuroscience, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
| | - Ming Li
- Department of Neurology and China-America Institute of Neuroscience, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
| | - Di Wu
- Department of Neurology and China-America Institute of Neuroscience, Xuanwu Hospital, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
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Yamato K, Nakajo Y, Yamamoto-Imoto H, Kokame K, Miyata T, Takahashi JC, Kataoka H, Yanamoto H. Low-Dose Activated Protein C Suppresses the Development of Cerebral Infarction and Neurological Deficits in Mice. NEUROSURGERY OPEN 2020. [DOI: 10.1093/neuopn/okaa014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
BACKGROUND
A large prospective study previously reported that a higher plasma level of protein C (PC) was associated with a lower incidence of ischemic stroke.
OBJECTIVE
To investigate the neuroprotective properties of activated PC (APC) against acute ischemic stroke using the 3-vessel occlusion model.
METHODS
Male C57BL/6J mice received APC (human APC) at 0.25, 0.5, or 1.0 (low dose) or 2.0, 4.0, or 8.0 mg/kg (high dose). Edaravone (Eda) (1.0, 3.0, or 10 mg/kg, a neuroprotectant approved for use in Japan), albumin (2.0 mg/kg), heparin (100 or 600 U/kg), or saline was used as the control. The drug or control was administered intravenously twice in the initial 24 h or 5 times in 3 d, starting 5 min after the induction of ischemia.
RESULTS
Low-dose APC significantly reduced lesion volumes, not affecting the depth of ischemia. High-dose APC did not significantly reduce lesion volumes, causing hemorrhagic transformation in some cases. In the chronic phase, lesion volumes were significantly suppressed in the APC or Eda group, and only the APC group showed a significant attenuation of neurological deficits. The protease-activated receptor (PAR)-1 antagonist SCH79797, administered during preischemia, completely abolished APC-induced neuroprotection. The overshoot-like abrupt recovery in regional cerebral blood flow observed in the control in the initial reperfusion phase was significantly suppressed by the APC treatment, indicating that the cerebral autoregulation system, consisting of endothelial cells and blood-brain barrier functions, was preserved.
CONCLUSION
Low-dose APC, potentially via the PAR-1-dependent anti-inflammatory cascade, protects the brain against ischemic stroke without increasing the risk of hemorrhagic transformation or death.
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Affiliation(s)
- Keiko Yamato
- Laboratory of Neurology and Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Yukako Nakajo
- Laboratory of Neurology and Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Japan
- Research Laboratories, Rakuwa-kai Otowa Hospital, Kyoto, Japan
| | - Hitomi Yamamoto-Imoto
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Koichi Kokame
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Toshiyuki Miyata
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Jun C Takahashi
- Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Hiroharu Kataoka
- Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Hiroji Yanamoto
- Laboratory of Neurology and Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Japan
- Department of Cardiovascular Science, Division of Surgical Medicine, Osaka University Graduate School of Medicine, Suita, Japan
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Perez E, Viziano A, Al-Zaghal Z, Telischi FF, Sangaletti R, Jiang W, Dietrich WD, King C, Hoffer ME, Rajguru SM. Anatomical Correlates and Surgical Considerations for Localized Therapeutic Hypothermia Application in Cochlear Implantation Surgery. Otol Neurotol 2020; 40:1167-1177. [PMID: 31318786 PMCID: PMC6750193 DOI: 10.1097/mao.0000000000002373] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Application of localized, mild therapeutic hypothermia during cochlear implantation (CI) surgery is feasible for residual hearing preservation.
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Affiliation(s)
| | - Andrea Viziano
- Department of Otolaryngology.,Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Rome, Italy
| | | | | | | | - Weitao Jiang
- Department of Biomedical Engineering, University of Miami, Miami, Florida
| | - William Dalton Dietrich
- Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami, Miami, Florida
| | | | | | - Suhrud M Rajguru
- Department of Otolaryngology.,Department of Biomedical Engineering, University of Miami, Miami, Florida
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Wu L, Wu D, Yang T, Xu J, Chen J, Wang L, Xu S, Zhao W, Wu C, Ji X. Hypothermic neuroprotection against acute ischemic stroke: The 2019 update. J Cereb Blood Flow Metab 2020; 40:461-481. [PMID: 31856639 PMCID: PMC7026854 DOI: 10.1177/0271678x19894869] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 11/14/2019] [Accepted: 11/18/2019] [Indexed: 02/06/2023]
Abstract
Acute ischemic stroke is a leading cause of death and disability worldwide. Therapeutic hypothermia has long been considered as one of the most robust neuroprotective strategies. Although the neuroprotective effects of hypothermia have only been confirmed in patients with global cerebral ischemia after cardiac arrest and in neonatal hypoxic ischemic encephalopathy, establishing standardized protocols and strictly controlling the key parameters may extend its application in other brain injuries, such as acute ischemic stroke. In this review, we discuss the potential neuroprotective effects of hypothermia, its drawbacks evidenced in previous studies, and its potential clinical application for acute ischemic stroke especially in the era of reperfusion. Based on the different conditions between bench and bedside settings, we demonstrate the importance of vascular recanalization for neuroprotection of hypothermia by analyzing numerous literatures regarding hypothermia in focal cerebral ischemia. Then, we make a thorough analysis of key parameters of hypothermia and introduce novel hypothermic therapies. We advocate in favor of the process of clinical translation of intra-arterial selective cooling infusion in the era of reperfusion and provide insights into the prospects of hypothermia in acute ischemic stroke.
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Affiliation(s)
- Longfei Wu
- Department of Neurology and China-America Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Di Wu
- Department of Neurology and China-America Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Tuo Yang
- Department of Neurology, Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jin Xu
- Department of Library, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Jian Chen
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Luling Wang
- Department of Neurology and China-America Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Shuaili Xu
- Department of Neurology and China-America Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Wenbo Zhao
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Chuanjie Wu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Xunming Ji
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
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Kalisvaart ACJ, Prokop BJ, Colbourne F. Hypothermia: Impact on plasticity following brain injury. Brain Circ 2019; 5:169-178. [PMID: 31950092 PMCID: PMC6950515 DOI: 10.4103/bc.bc_21_19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 10/28/2019] [Indexed: 12/13/2022] Open
Abstract
Therapeutic hypothermia (TH) is a potent neuroprotectant against multiple forms of brain injury, but in some cases, prolonged cooling is needed. Such cooling protocols raise the risk that TH will directly or indirectly impact neuroplasticity, such as after global and focal cerebral ischemia or traumatic brain injury. TH, depending on the depth and duration, has the potential to broadly affect brain plasticity, especially given the spatial, temporal, and mechanistic overlap with the injury processes that cooling is used to treat. Here, we review the current experimental and clinical evidence to evaluate whether application of TH has any adverse or positive effects on postinjury plasticity. The limited available data suggest that mild TH does not appear to have any deleterious effect on neuroplasticity; however, we emphasize the need for additional high-quality preclinical and clinical work in this area.
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Li H, Tan X, Xue Q, Zhu JH, Chen G. Combined application of hypothermia and medical gases in cerebrovascular diseases. Med Gas Res 2019; 8:172-175. [PMID: 30713671 PMCID: PMC6352567 DOI: 10.4103/2045-9912.248269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 11/06/2018] [Indexed: 01/11/2023] Open
Abstract
Cerebrovascular diseases have a heavy burden on society and the family. At present, in the treatment of cerebrovascular diseases, the recognized effective treatment method is a thrombolytic therapy after cerebral infarction, but limited to the time window problem, many patients cannot benefit. Other treatments for cerebrovascular disease are still in the exploration stage. The study found that medical gas and hypothermia have brain protection effects. Further research found that when the two are used in combination, the therapeutic effect has a superimposed effect. This article reviews the current research progress of hypothermia therapy combined with medical gas therapy for cerebrovascular disease.
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Affiliation(s)
- Hao Li
- Department of Neurology, the First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | - Xin Tan
- Department of Neurology, the First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | - Qun Xue
- Department of Neurology, the First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | - Jue-Hua Zhu
- Department of Neurology, the First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | - Gang Chen
- Department of Neurosurgery & Brain and Nerve Research Laboratory, the First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
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8
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Abstract
Therapeutic hypothermia (TH) is a potent neuroprotective therapy in experimental cerebral ischemia, with multiple effects at several stages of the ischemic cascade. In animals, TH is so powerful that all preclinical stroke studies require strict temperature control. In humans, multiple clinical studies documented powerful protection with TH after accidental neonatal hypoxic-ischemic injury and global cerebral ischemia with return of spontaneous circulation after cardiac arrest. National and international guidelines recommend TH for selected survivors of global ischemia, with profound benefits seen. Recently, a study comparing target temperature 33-36°C failed to demonstrate significant effects in cardiac arrest patients. Additionally, clinical trials of TH for head trauma and stroke have so far failed to confirm benefit in humans despite a vast preclinical literature. Therefore, it is now critical to understand the fundamental explanation for the success of TH in some, but famously not all, clinical trials. TH in animals appears to work when used soon after ischemia onset; for a short duration; and at a deep target temperature.
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9
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Liu K, Khan H, Geng X, Zhang J, Ding Y. Pharmacological hypothermia: a potential for future stroke therapy? Neurol Res 2017; 38:478-90. [PMID: 27320243 DOI: 10.1080/01616412.2016.1187826] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Mild physical hypothermia after stroke has been associated with positive outcomes. Despite the well-studied beneficial effects of hypothermia in the treatment of stroke, lack of precise temperature control, intolerance for the patient, and immunosuppression are some of the reasons which limit its clinical translation. Pharmacologically induced hypothermia has been explored as a possible treatment option following stroke in animal models. Currently, there are eight classes of pharmacological agents/agonists with hypothermic effects affecting a multitude of systems including cannabinoid, opioid, transient receptor potential vanilloid 1 (TRPV1), neurotensin, thyroxine derivatives, dopamine, gas, and adenosine derivatives. Interestingly, drugs in the TRPV1, neurotensin, and thyroxine families have been shown to have effects in thermoregulatory control in decreasing the compensatory hypothermic response during cooling. This review will briefly present drugs in the eight classes by summarizing their proposed mechanisms of action as well as side effects. Reported thermoregulatory effects of the drugs will also be presented. This review offers the opinion that these agents may be useful in combination therapies with physical hypothermia to achieve faster and more stable temperature control in hypothermia.
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Affiliation(s)
- Kaiyin Liu
- a Department of Neurological Surgery , Wayne State University School of Medicine , Detroit , MI , USA
| | - Hajra Khan
- a Department of Neurological Surgery , Wayne State University School of Medicine , Detroit , MI , USA
| | - Xiaokun Geng
- a Department of Neurological Surgery , Wayne State University School of Medicine , Detroit , MI , USA.,b Department of Neurology, Beijing Luhe Hospital , Capital Medical University , Beijing , China
| | - Jun Zhang
- c China-America Institute of Neuroscience, Xuanwu Hospital , Capital Medical University , Beijing , China
| | - Yuchuan Ding
- a Department of Neurological Surgery , Wayne State University School of Medicine , Detroit , MI , USA.,b Department of Neurology, Beijing Luhe Hospital , Capital Medical University , Beijing , China
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Iglesias-Rey R, Vieites-Prado A, Argibay B, Campos F, Bañobre-López M, Sobrino T, Rivas J, Castillo J. Magnetocaloric effect for inducing hypothermia as new therapeutic strategy for stroke: A physical approach. J Appl Biomed 2017. [DOI: 10.1016/j.jab.2016.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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11
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Tetramethylpyrazine Nitrone Improves Neurobehavioral Functions and Confers Neuroprotection on Rats with Traumatic Brain Injury. Neurochem Res 2016; 41:2948-2957. [DOI: 10.1007/s11064-016-2013-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/15/2016] [Accepted: 07/20/2016] [Indexed: 11/26/2022]
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12
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Abstract
Hypothermia is the most potent neuroprotective therapy available. Clinical use of hypothermia is limited by technology and homeostatic mechanisms that maintain core body temperature. Recent advances in intravascular cooling catheters and successful trials of hypothermia for cardiac arrest revivified interest in hypothermia for stroke, resulting in Phase 1 clinical trials and plans for further development. Given the recent spate of neuroprotective therapy failures, we sought to clarify whether clinical trials of therapeutic hypothermia should be mounted in stroke patients. We reviewed the preclinical and early clinical trials of hypothermia for a variety of indications, the putative mechanisms for neuroprotection with hypothermia, and offer several hypotheses that remain to be tested in clinical trials. Therapeutic hypothermia is promising, but further Phase 1 and Phase 2 development efforts are needed to ensure that cooling of stroke patients is safe, before definitive efficacy trials.
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Affiliation(s)
- Patrick D. Lyden
- Neurology and Research Services of the San Diego Veteran's Administration Medical Center and the Department of Neurosciences, University of California, San Diego, CA, USA
| | - Derk Krieger
- Section of Stroke and Neurological Critical Care, The Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Midori Yenari
- Department of Neurology, University of California San Francisco School of Medicine, San Francisco, CA, USA
- Neurology Department of the San Francisco Veteran's Administration Medical Center, San Francisco, CA, USA
| | - W. Dalton Dietrich
- Department of Neurological Surgery, University of Miami School of Medicine, Miami, FL, USA
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Tamames I, King C, Bas E, Dietrich WD, Telischi F, Rajguru SM. A cool approach to reducing electrode-induced trauma: Localized therapeutic hypothermia conserves residual hearing in cochlear implantation. Hear Res 2016; 339:32-9. [PMID: 27260269 DOI: 10.1016/j.heares.2016.05.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Revised: 05/19/2016] [Accepted: 05/26/2016] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The trauma caused during cochlear implant insertion can lead to cell death and a loss of residual hair cells in the cochlea. Various therapeutic approaches have been studied to prevent cochlear implant-induced residual hearing loss with limited success. In the present study, we show the efficacy of mild to moderate therapeutic hypothermia of 4 to 6 °C applied to the cochlea in reducing residual hearing loss associated with the electrode insertion trauma. APPROACH Rats were randomly distributed in three groups: control contralateral cochleae, normothermic implanted cochleae and hypothermic implanted cochleae. Localized hypothermia was delivered to the middle turn of the cochlea for 20 min before and after implantation using a custom-designed probe perfused with cooled fluorocarbon. Auditory brainstem responses (ABRs) were recorded to assess the hearing function prior to and post-cochlear implantation at various time points up to 30 days. At the conclusion of the trials, inner ears were harvested for histology and cell count. The approach was extended to cadaver temporal bones to study the potential surgical approach and efficacy of our device. In this case, the hypothermia probe was placed next to the round window niche via the facial recess or a myringotomy. MAIN RESULTS A significant loss of residual hearing was observed in the normothermic implant group. Comparatively, the residual hearing in the cochleae receiving therapeutic hypothermia was significantly conserved. Histology confirmed a significant loss of outer hair cells in normothermic cochleae receiving the surgical trauma when compared to the hypothermia treated group. In human temporal bones, a controlled and effective cooling of the cochlea was achieved using our approach. SIGNIFICANCE Collectively, these results suggest that therapeutic hypothermia during cochlear implantation may reduce traumatic effects of electrode insertion and improve conservation of residual hearing.
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Affiliation(s)
- Ilmar Tamames
- Department of Biomedical Engineering, Seattle, WA, USA
| | | | - Esperanza Bas
- Department of Otolaryngology, University of Miami, Miami, FL, 33136, USA
| | - W Dalton Dietrich
- Department of Neurological Surgery, University of Miami, Miami, FL, 33136, USA
| | - Fred Telischi
- Department of Otolaryngology, University of Miami, Miami, FL, 33136, USA
| | - Suhrud M Rajguru
- Department of Biomedical Engineering, Seattle, WA, USA; Department of Otolaryngology, University of Miami, Miami, FL, 33136, USA.
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Subdural hematoma decompression model: A model of traumatic brain injury with ischemic-reperfusional pathophysiology: A review of the literature. Behav Brain Res 2016; 340:23-28. [PMID: 27235716 DOI: 10.1016/j.bbr.2016.05.055] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 05/20/2016] [Accepted: 05/24/2016] [Indexed: 11/23/2022]
Abstract
The prognosis for patients with traumatic brain injury (TBI) with subdural hematoma (SDH) remains poor. In accordance with an increasing elderly population, the incidence of geriatric TBI with SDH is rising. An important contributor to the neurological injury associated with SDH is the ischemic damage which is caused by raised intracranial pressure (ICP) producing impaired cerebral perfusion. To control intracranial hypertension, the current management consists of hematoma evacuation with or without decompressive craniotomy. This removal of the SDH results in the immediate reversal of global ischemia accompanied by an abrupt reduction of mass lesion and an ensuing reperfusion injury. Experimental models can play a critical role in improving our understanding of the underlying pathophysiology and in exploring potential treatments for patients with SDH. In this review, we describe the epidemiology, pathophysiology and clinical background of SDH.
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Bonds BW, Hu P, Li Y, Yang S, Colton K, Gonchigar A, Cheriyan J, Grissom T, Fang R, Stein DM. Predictive value of hyperthermia and intracranial hypertension on neurological outcomes in patients with severe traumatic brain injury. Brain Inj 2015; 29:1642-7. [DOI: 10.3109/02699052.2015.1075157] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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16
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Han Z, Liu X, Luo Y, Ji X. Therapeutic hypothermia for stroke: Where to go? Exp Neurol 2015; 272:67-77. [PMID: 26057949 DOI: 10.1016/j.expneurol.2015.06.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 05/16/2015] [Accepted: 06/04/2015] [Indexed: 01/08/2023]
Abstract
Ischemic stroke is a major cause of death and long-term disability worldwide. Thrombolysis with recombinant tissue plasminogen activator is the only proven and effective treatment for acute ischemic stroke; however, therapeutic hypothermia is increasingly recognized as having a tissue-protective function and positively influencing neurological outcome, especially in cases of ischemia caused by cardiac arrest or hypoxic-ischemic encephalopathy in newborns. Yet, many aspects of hypothermia as a treatment for ischemic stroke remain unknown. Large-scale studies examining the effects of hypothermia on stroke are currently underway. This review discusses the mechanisms underlying the effect of hypothermia, as well as trends in hypothermia induction methods, methods for achieving optimal protection, side effects, and therapeutic strategies combining hypothermia with other neuroprotective treatments. Finally, outstanding issues that must be addressed before hypothermia treatment is implemented at a clinical level are also presented.
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Affiliation(s)
- Ziping Han
- Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Xiangrong Liu
- Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Yumin Luo
- Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, Beijing 100053, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing 100053, China
| | - Xunming Ji
- Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, Beijing 100053, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing 100053, China; Department of Neurosurgery, Xuanwu Hospital of Capital Medical University, Beijing 100053, China.
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17
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Ruan Z, Wang HM, Huang XT, Fu Y, Wu J, Ye CY, Li JL, Wu L, Gong Q, Zhao WM, Zhang HY. A novel caffeoyl triterpene attenuates cerebral ischemic injury with potent anti-inflammatory and hypothermic effects. J Neurochem 2015; 133:93-103. [PMID: 25626516 DOI: 10.1111/jnc.13046] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 01/08/2015] [Accepted: 01/19/2015] [Indexed: 12/19/2022]
Abstract
Despite the intense efforts in searching for stroke therapies, an urgent need still exists to explore novel neuroprotective agents for ischemic stroke that have high efficacy and wide therapeutic time-window. Here, we provide the first demonstration that 28-O-caffeoyl betulin (B-CA), a novel derivative of naturally occurring caffeoyl triterpene, could significantly alleviate brain infarction and neurological deficit when given as late as 6 h after transient middle cerebral artery occlusion in the rat. Moreover, post-ischemia B-CA administration exhibited long-term (14 days post stroke) protective effects on both brain infarction and functional (i.e., motor and sensory) deficits. Protective B-CA effects correlated with decreased inflammatory responses as indicated by inhibition of microglia and astrocyte activation [stained with ionized calcium-binding adapter molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP) antibody, respectively], as well as suppression of tumor necrosis factor-α, interleukin-1β, and cyclooxygenase-2 overproduction in the ipsilateral cortex of ischemic rat. B-CA administration caused significant hypothermia in the focal cerebral ischemic rat, which may contribute to its ameliorative effects on brain damage and inflammation. In view of its potency in wide therapeutic time-window, robust anti-inflammatory and hypothermic effects, this novel caffeoyl triterpene derivative may lead toward the development of effective therapeutic strategies for the treatment of ischemic stroke.
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Affiliation(s)
- Zhi Ruan
- CAS Key Laboratory of Receptor Research, Department of Pharmacology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
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Murtha LA, McLeod DD, McCann SK, Pepperall D, Chung S, Levi CR, Calford MB, Spratt NJ. Short-duration hypothermia after ischemic stroke prevents delayed intracranial pressure rise. Int J Stroke 2013; 9:553-9. [PMID: 24025084 DOI: 10.1111/ijs.12181] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 07/22/2013] [Indexed: 12/01/2022]
Abstract
BACKGROUND Intracranial pressure elevation, peaking three to seven post-stroke is well recognized following large strokes. Data following small-moderate stroke are limited. Therapeutic hypothermia improves outcome after cardiac arrest, is strongly neuroprotective in experimental stroke, and is under clinical trial in stroke. Hypothermia lowers elevated intracranial pressure; however, rebound intracranial pressure elevation and neurological deterioration may occur during rewarming. HYPOTHESES (1) Intracranial pressure increases 24 h after moderate and small strokes. (2) Short-duration hypothermia-rewarming, instituted before intracranial pressure elevation, prevents this 24 h intracranial pressure elevation. METHODS Long-Evans rats with two hour middle cerebral artery occlusion or outbred Wistar rats with three hour middle cerebral artery occlusion had intracranial pressure measured at baseline and 24 h. Wistars were randomized to 2·5 h hypothermia (32·5°C) or normothermia, commencing 1 h after stroke. RESULTS In Long-Evans rats (n = 5), intracranial pressure increased from 10·9 ± 4·6 mmHg at baseline to 32·4 ± 11·4 mmHg at 24 h, infarct volume was 84·3 ± 15·9 mm(3) . In normothermic Wistars (n = 10), intracranial pressure increased from 6·7 ± 2·3 mmHg to 31·6 ± 9·3 mmHg, infarct volume was 31·3 ± 18·4 mm(3) . In hypothermia-treated Wistars (n = 10), 24 h intracranial pressure did not increase (7·0 ± 2·8 mmHg, P < 0·001 vs. normothermia), and infarct volume was smaller (15·4 ± 11·8 mm(3) , P < 0·05). CONCLUSIONS We saw major intracranial pressure elevation 24 h after stroke in two rat strains, even after small strokes. Short-duration hypothermia prevented the intracranial pressure rise, an effect sustained for at least 18 h after rewarming. The findings have potentially important implications for design of future clinical trials.
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Affiliation(s)
- L A Murtha
- University of Newcastle and Hunter Medical Research Institute, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, NSW, Australia
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19
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Li J, Luan X, Lai Q, Clark JC, McAllister JP, Fessler R, Diaz FG, Ding Y. Long-term neuroprotection induced by regional brain cooling with saline infusion into ischemic territory in rats: a behavioral analysis. Neurol Res 2013; 26:677-83. [PMID: 15327759 DOI: 10.1179/016164104225015903] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
The neuroprotective effect of hypothermia has long been recognized. Our recent studies have demonstrated the significant therapeutic value of local brain cooling in the ischemic territory prior to reperfusion in stroke, with reduced infarction and inflammatory responses up to 48 hours of reperfusion. The goal of this study was to determine if local brain cooling, produced by infusion of cold saline, could induce long-term functional improvement after stroke. A hollow filament was used to block the middle cerebral artery (MCA) for 3 hours, and then to locally infuse the ischemic territory with 6 ml cold saline (20 degrees C) for 10 minutes prior to reperfusion. This brain cooling infusion induced a significant (p < 0.01) decrease in neurologic deficits and significantly (p < 0.01) improved motor behavior in ischemic rats after 14 days of reperfusion, compared with ischemic rats without local cold saline infusion. This improvement continued for up to 28 days after reperfusion. No significant difference in motor performance was observed between the brain cooling infusion and normal control groups. Significant (p < 0.01) reductions in infarct volume were also evident. In conclusion, a local cerebral hypothermia induced by local saline infusion prior to reperfusion produced a long-term functional recovery after ischemic stroke. A therapeutic procedure, which combines prereperfusion infusion into an ischemic region with coincident cerebral hypothermia and perhaps subsequent recanalization of an occluded intracranial vessel, may improve the outcome for stroke patients.
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Affiliation(s)
- Jie Li
- Department of Neurological Surgery, Wayne State University School of Medicine, Canfield, Detroit, MI 48201, USA
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20
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Wong JM, Ziewacz JE, Ho AL, Panchmatia JR, Kim AH, Bader AM, Thompson BG, Du R, Gawande AA. Patterns in neurosurgical adverse events: open cerebrovascular neurosurgery. Neurosurg Focus 2013; 33:E15. [PMID: 23116095 DOI: 10.3171/2012.7.focus12181] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT As part of a project to devise evidence-based safety interventions for specialty surgery, we sought to review current evidence concerning the frequency of adverse events in open cerebrovascular neurosurgery and the state of knowledge regarding methods for their reduction. This review represents part of a series of papers written to consolidate information about these events and preventive measures as part of an ongoing effort to ascertain the utility of devising system-wide policies and safety tools to improve neurosurgical practice. METHODS The authors performed a PubMed search using search terms "cerebral aneurysm", "cerebral arteriovenous malformation", "intracerebral hemorrhage", "intracranial hemorrhage", "subarachnoid hemorrhage", and "complications" or "adverse events." Only papers that specifically discussed the relevant complication rates were included. Papers were chosen to be included to maximize the range of rates of occurrence for the reported adverse events. RESULTS The review revealed hemorrhage-related hyperglycemia (incidence rates ranging from 27% to 71%) and cerebral salt-wasting syndromes (34%-57%) to be the most common perioperative adverse events related to subarachnoid hemorrhage (SAH). Next in terms of frequency was new cerebral infarction associated with SAH, with a rate estimated at 40%. Many techniques are advocated for use during surgery to minimize risk of this development, including intraoperative neurophysiological monitoring, but are not universally used due to surgeon preference and variable availability of appropriate staffing and equipment. The comparative effectiveness of using or omitting monitoring technologies has not been evaluated. The incidence of perioperative seizure related to vascular neurosurgery is unknown, but reported seizure rates from observational studies range from 4% to 42%. There are no standard guidelines for the use of seizure prophylaxis in these patients, and there remains a need for prospective studies to support such guidelines. Intraoperative rupture occurs at a rate of 7% to 35% and depends on aneurysm location and morphology, history of rupture, surgical technique, and surgeon experience. Preventive strategies include temporary vascular clipping. Technical adverse events directly involving application of the aneurysm clip include incomplete aneurysm obliteration and parent vessel occlusion. The rates of these events range from 5% to 18% for incomplete obliteration and 3% to 12% for major vessel occlusion. Intraoperative angiography is widely used to confirm clip placement; adjuncts include indocyanine green video angiography and microvascular Doppler ultrasonography. Use of these technologies varies by institution. DISCUSSION A significant proportion of these complications may be avoidable through development and testing of standardized protocols to incorporate monitoring technologies and specific technical practices, teamwork and communication, and concentrated volume and specialization. Collaborative monitoring and evaluation of such protocols are likely necessary for the advancement of open cerebrovascular neurosurgical quality.
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Affiliation(s)
- Judith M Wong
- Department of Health Policy and Management, Harvard School of Public Health, Brigham and Women’s Hospital, Street, Boston, Massachusetts 02115, USA
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Abstract
Ischaemic stroke is one of the leading causes of death and disability worldwide, and intravenous alteplase is the only proven effective treatment in the acute setting. Hypothermia has been shown to improve neurological outcomes after global ischaemia-hypoxia in comatose patients who have had cardiac arrest, and is one of the most extensively studied and powerful therapeutic strategies in acute ischaemic stroke. The protective mechanisms of therapeutic hypothermia affect the ischaemic cascade across several parallel pathways and, when coupled with reperfusion strategies, might yield synergistic benefits for patients who have had a stroke. Technological advances have allowed hypothermia to be induced rapidly, and the treatment has been used safely in acute stroke patients. Conclusive efficacy trials assessing therapeutic hypothermia combined with reperfusion therapies in acute ischaemic stroke are ongoing.
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Yang D, Nakajo Y, Iihara K, Kataoka H, Yanamoto H. Alogliptin, a dipeptidylpeptidase-4 inhibitor, for patients with diabetes mellitus type 2, induces tolerance to focal cerebral ischemia in non-diabetic, normal mice. Brain Res 2013; 1517:104-13. [PMID: 23602966 DOI: 10.1016/j.brainres.2013.04.015] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 04/05/2013] [Accepted: 04/08/2013] [Indexed: 12/15/2022]
Abstract
Effective interventions that provide obvious neuroprotection are currently fairly limited. Glucagon-like peptide-1 (GLP-1), an enhancer of insulin production with a trophic effect on β cells in the islets, has been found to be trophic for neuronal cells. Alogliptin benzoate (AGL), a selective inhibitor of dipeptidylpeptidase-4 (DPP-4) functioning as a long-acting agonist of GLP-1, is in clinical use worldwide for patients with diabetes mellitus type 2. To clarify whether administration of AGL, independent of the insulinotropic effect, protects the brain against focal ischemia, we investigated the effect of AGL on the development of cerebral infarction in non-diabetic normal mice. Male C57BL/6J mice were administered AGL (7.5, 15, or 30μg) once a day for three weeks by intragastric gavage. After the induction of temporary focal ischemia, volumes of infarcted lesions and neurological deficits were analyzed at 24h (acute phase) and seven days (chronic phase). In the acute phase, significant reductions were observed in the volumes of infarcted lesions (p=0.009), and in the severity of neurological deficits (p=0.004), in the group treated with 15μg of alogliptin benzoate, but not the 7.5 or 30μg-treated groups. This significant reduction in volumes of infarcted lesions persisted into the chronic phase. At the end of the AGL treatment; before the induction of ischemia, the levels of brain-derived neurotrophic factor (BDNF), a potent neuroprotectant in the brain, were elevated in the cortex (p=0.008), or in the whole forebrain (p=0.023). AGL could be used as a daily neuroprotectant or an enhancer of BDNF production aiming to attenuate cerebral injuries, for the growing number of people who have the risk of ischemic stroke.
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Affiliation(s)
- Dong Yang
- Laboratory of Neurology and Neurosurgery, National Cerebral and Cardiovascular Research Center, Suita 565-8565, Japan
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23
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Zgavc T, De Geyter D, Ceulemans AG, Stoop W, Hachimi-Idrissi S, Michotte Y, Sarre S, Kooijman R. Mild hypothermia reduces activated caspase-3 up to 1 week after a focal cerebral ischemia induced by endothelin-1 in rats. Brain Res 2013; 1501:81-8. [PMID: 23357472 DOI: 10.1016/j.brainres.2013.01.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 01/15/2013] [Accepted: 01/19/2013] [Indexed: 12/27/2022]
Abstract
Hypothermia is a promising neuroprotective therapy that has been shown to reduce apoptosis after an ischemic insult. This study evaluated the effect of mild hypothermia on activated caspase-3 up to 1 week after the induction of a stroke. Endothelin-1 (Et-1) was used to elicit transient focal cerebral ischemia in rats. Twenty minutes after the ischemic insult, a state of mild hypothermia (33°C) was imposed for a duration of 2h. The functional outcome, infarct volume and activated caspase-3 immunoreactivity (IR) were assessed at 8, 24 and 72h, and one week after the insult. During the experiment the cerebral blood flow (CBF) was measured via Laser Doppler Flowmetry. Hypothermia improved the neurological outcome at all of the time points studied compared to the normothermic group, and was associated with a reduction in infarct volume. In both groups, activated caspase-3 IR peaked 24h after the Et-1 induced insult and hypothermia significantly reduced the number of apoptotic cells at 8h, 24h and 1 week after ischemia. Furthermore, the hypothermic treatment did not affect the CBF in the Et-1 model. These findings indicate that in the Et-1 model, hypothermia exerts a long lasting effect on stroke-induced apoptosis.
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Affiliation(s)
- Tine Zgavc
- Department of Pharmaceutical Chemistry and Drug Analysis, Center for Neuroscience, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium.
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24
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Abstract
OPINION STATEMENT Therapeutic hypothermia has proven neuroprotective effects in global cerebral ischemia. Indications for hypothermia induction include cardiac arrest and neonatal asphyxia. The two general methods of induced hypothermia are either surface cooling or endovascular cooling. Hypothermia should be induced as early as possible to achieve maximum neuroprotection and edema blocking effect. Endovascular cooling has the benefit of shorter time to reach target temperature but catheter insertion requires expertise and training, which may be a barrier to widespread availability. The optimum method of cooling is yet to be determined but a multimodal approach is necessary to address three phases of cooling: induction, maintentance, and rewarm. Specifying core practitioners who are well-versed in established guidelines can help integrate the multidisciplinary team that is needed to successfully implement cooling protocols. Reducing shivering to make heat exchange more efficient with tighter temperature control enables quicker time to target temperature and avoids rewarming which can lead to inadvertent increase in intracranial pressure and cerebral edema. Promising applications but yet to be determined is whether hypothermia treatment can improve outcomes in acute ischemic stroke or traumatic brain injury.
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Affiliation(s)
- Shlee S Song
- Department of Neurology, Cedars-Sinai Medical Center, 8730 Alden Drive, Suite E-240, Los Angeles, CA, 90048, USA
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25
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Lückl J, Dreier JP, Szabados T, Wiesenthal D, Bari F, Greenberg JH. Peri-infarct flow transients predict outcome in rat focal brain ischemia. Neuroscience 2012; 226:197-207. [PMID: 22986160 DOI: 10.1016/j.neuroscience.2012.08.049] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 08/10/2012] [Accepted: 08/23/2012] [Indexed: 01/09/2023]
Abstract
Spreading depolarizations are accompanied by transient changes in cerebral blood flow (CBF). In a post hoc analysis of previously studied control rats we analyzed CBF time courses after middle cerebral artery occlusion in the rat in order to test whether intra-ischemic flow, reperfusion, and different parameters of peri-infarct flow transients (PIFTs) (amplitude, number) can predict outcome. Sprague-Dawley rats anesthetized with either halothane (n=23) or isoflurane (n=32) underwent 90-min filament occlusion of the middle cerebral artery followed by 72 h of reperfusion. The infarct size was determined by 2,3,5-triphenyltetrazolium chloride staining. Relative CBF changes were monitored by laser Doppler flowmetry at 4-5 mm lateral, and 1-2mm posterior to Bregma. An additional filament occlusion study (n=12) was performed to validate that PIFTs were coupled to direct current shifts of spreading depolarization. The PIFT-direct current shift study revealed that every PIFT was associated with a negative direct current shift typical of spreading depolarization. Post-hoc analysis showed that the number of PIFTs, especially with the combination of intra-ischemic level of flow, can predict the development of cortical infarcts. These findings show that PIFTs can serve as an early biomarker in predicting outcome in preclinical animal studies.
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Affiliation(s)
- J Lückl
- Department of Neurology, University of Pennsylvania, 415 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA 19104-6063, USA
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26
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Mewes A, Franke H, Singer D. Organotypic brain slice cultures of adult transgenic P301S mice--a model for tauopathy studies. PLoS One 2012; 7:e45017. [PMID: 22984603 PMCID: PMC3439393 DOI: 10.1371/journal.pone.0045017] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 08/14/2012] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Organotypic brain slice cultures represent an excellent compromise between single cell cultures and complete animal studies, in this way replacing and reducing the number of animal experiments. Organotypic brain slices are widely applied to model neuronal development and regeneration as well as neuronal pathology concerning stroke, epilepsy and Alzheimer's disease (AD). AD is characterized by two protein alterations, namely tau hyperphosphorylation and excessive amyloid β deposition, both causing microglia and astrocyte activation. Deposits of hyperphosphorylated tau, called neurofibrillary tangles (NFTs), surrounded by activated glia are modeled in transgenic mice, e.g. the tauopathy model P301S. METHODOLOGY/PRINCIPAL FINDINGS In this study we explore the benefits and limitations of organotypic brain slice cultures made of mature adult transgenic mice as a potential model system for the multifactorial phenotype of AD. First, neonatal (P1) and adult organotypic brain slice cultures from 7- to 10-month-old transgenic P301S mice have been compared with regard to vitality, which was monitored with the lactate dehydrogenase (LDH)- and the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays over 15 days. Neonatal slices displayed a constant high vitality level, while the vitality of adult slice cultures decreased significantly upon cultivation. Various preparation and cultivation conditions were tested to augment the vitality of adult slices and improvements were achieved with a reduced slice thickness, a mild hypothermic cultivation temperature and a cultivation CO(2) concentration of 5%. Furthermore, we present a substantial immunohistochemical characterization analyzing the morphology of neurons, astrocytes and microglia in comparison to neonatal tissue. CONCLUSION/SIGNIFICANCE Until now only adolescent animals with a maximum age of two months have been used to prepare organotypic brain slices. The current study provides evidence that adult organotypic brain slice cultures from 7- to 10-month-old mice independently of the transgenic modification undergo slow programmed cell death, caused by a dysfunction of the neuronal repair systems.
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Affiliation(s)
- Agneta Mewes
- Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine (BBZ), University of Leipzig, Leipzig, Germany
| | - Heike Franke
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, University of Leipzig, Leipzig, Germany
| | - David Singer
- Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine (BBZ), University of Leipzig, Leipzig, Germany
- * E-mail:
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27
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Zgavc T, Ceulemans AG, Hachimi-Idrissi S, Kooijman R, Sarre S, Michotte Y. The neuroprotective effect of post ischemic brief mild hypothermic treatment correlates with apoptosis, but not with gliosis in endothelin-1 treated rats. BMC Neurosci 2012; 13:105. [PMID: 22920191 PMCID: PMC3502503 DOI: 10.1186/1471-2202-13-105] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Accepted: 08/21/2012] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Stroke remains one of the most common diseases with a serious impact on quality of life but few effective treatments exist. Mild hypothermia (33°C) is a promising neuroprotective therapy in stroke management. This study investigated whether a delayed short mild hypothermic treatment is still beneficial as neuroprotective strategy in the endothelin-1 (Et-1) rat model for a transient focal cerebral ischemia. Two hours of mild hypothermia (33°C) was induced 20, 60 or 120 minutes after Et-1 infusion. During the experiment the cerebral blood flow (CBF) was measured via Laser Doppler Flowmetry in the striatum, which represents the core of the infarct. Functional outcome and infarct volume were assessed 24 hours after the insult. In this sub-acute phase following stroke induction, the effects of the hypothermic treatment on apoptosis, phagocytosis and astrogliosis were assessed as well. Apoptosis was determined using caspase-3 immunohistochemistry, phagocytic cells were visualized by CD-68 expression and astrogliosis was studied by glial fibrillary acidic protein (GFAP) staining. RESULTS Cooling could be postponed up to 1 hour after the onset of the insult without losing its positive effects on neurological deficit and infarct volume. These results correlated with the caspase-3 staining. In contrast, the increased CD-68 expression post-stroke was reduced in the core of the insult with all treatment protocols. Hypothermia also reduced the increased levels of GFAP staining, even when it was delayed up to 2 hours after the insult. The study confirmed that the induction of the hypothermia treatment in the Et-1 model does not affect the CBF. CONCLUSIONS These data indicate that in the Et-1 rat model, a short mild hypothermic treatment delayed for 1 hour is still neuroprotective and correlates with apoptosis. At the same time, hypothermia also establishes a lasting inhibitory effect on the activation of astrogliosis.
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Affiliation(s)
- Tine Zgavc
- Department of Pharmaceutical Chemistry and Drug Analysis, Center for Neuroscience, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
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Kasam M, Yang B, Strong R, Schaar K, Misra V, Xi X, Grotta JC, Aronowski J, Savitz SI. Nitric oxide facilitates delivery and mediates improved outcome of autologous bone marrow mononuclear cells in a rodent stroke model. PLoS One 2012; 7:e32793. [PMID: 22412926 PMCID: PMC3296739 DOI: 10.1371/journal.pone.0032793] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 01/31/2012] [Indexed: 11/18/2022] Open
Abstract
Background Bone marrow mononuclear cells (MNC) represent an investigational treatment for stroke. The objective of this study was to determine the relevance of vasoactive mediators, generated in response to MNC injection, as factors regulating cerebral perfusion (CP), the biodistribution of MNC, and outcome in stroke. Methods Long Evans rats underwent transient middle cerebral artery occlusion. MNC were extracted from the bone marrow at 22 hrs and injected via the internal carotid artery or the femoral vein 2 hours later. CP was measured with MRI or continuous laser Doppler flowmetry. Serum samples were collected to measure vasoactive mediators. Animals were treated with the Nitric Oxide (NO) inhibitor, L-NAME, to establish the relevance of NO-signaling to the effect of MNC. Lesion size, MNC biodistribution, and neurological deficits were assessed. Results CP transiently increased in the peri-infarct region within 30 min after injecting MNC compared to saline or fibroblast control. This CP increase corresponded temporarily to serum NO elevation and was abolished by L-NAME. Pre-treatment with L-NAME reduced brain penetration of MNC and prevented MNC from reducing infarct lesion size and neurological deficits. Conclusions NO generation in response to MNC may represent a mechanism underlying how MNC enter the brain, reduce lesion size, and improve outcome in ischemic stroke.
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Affiliation(s)
- Mallikarjunarao Kasam
- Department of Neurology, Stroke Team, The University of Texas-Houston Medical School, Houston, Texas, United States of America
| | - Bing Yang
- Department of Neurology, Stroke Team, The University of Texas-Houston Medical School, Houston, Texas, United States of America
| | - Roger Strong
- Department of Neurology, Stroke Team, The University of Texas-Houston Medical School, Houston, Texas, United States of America
| | - Krystal Schaar
- Department of Neurology, Stroke Team, The University of Texas-Houston Medical School, Houston, Texas, United States of America
| | - Vivek Misra
- Department of Neurology, Stroke Team, The University of Texas-Houston Medical School, Houston, Texas, United States of America
| | - Xiaopei Xi
- Department of Neurology, Stroke Team, The University of Texas-Houston Medical School, Houston, Texas, United States of America
| | - James C. Grotta
- Department of Neurology, Stroke Team, The University of Texas-Houston Medical School, Houston, Texas, United States of America
| | - Jaroslaw Aronowski
- Department of Neurology, Stroke Team, The University of Texas-Houston Medical School, Houston, Texas, United States of America
| | - Sean I. Savitz
- Department of Neurology, Stroke Team, The University of Texas-Houston Medical School, Houston, Texas, United States of America
- * E-mail:
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29
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Yokobori S, Frantzen J, Bullock R, Gajavelli S, Burks S, Bramlett H, Dietrich WD. The Use of Hypothermia Therapy in Traumatic Ischemic / Reperfusional Brain Injury: Review of the Literatures. Ther Hypothermia Temp Manag 2011; 1:185-192. [PMID: 23439678 PMCID: PMC3579497 DOI: 10.1089/ther.2011.0012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Therapeutic mild hypothermia has been used widely in brain injury. It has evaluated in numerous clinical trials, and there is strong evidence for the use of hypothermia in treating patients with several types of ischemic / reperfusional (I/R) injuries, examples being cardiac arrest and neonatal hypoxic-ischemic encephalopathy.In spite of many basic research projects demonstrating effectiveness, therapeutic hypothermia has not been proven effective for the heterogeneous group of traumatic brain injury patients in multicenter clinical trials. In the latest clinical trial, however, researchers were able to demonstrate the significant beneficial effects of hypothermia in one specific group; patients with mass evacuated lesions. This suggested that mild therapeutic hypothermia might be effective for I/R related traumatic brain injury.In this article we have reviewed much of the previous literature concerning the mechanisms of I/R injury to the protective effects of mild therapeutic hypothermia.
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Affiliation(s)
- Shoji Yokobori
- Department of Neurosurgery, The Miami Project to Cure Paralysis University of Miami Miller school of Medicine, Miami, Florida
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30
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Meloni BP, Mastaglia FL, Knuckey NW. Therapeutic applications of hypothermia in cerebral ischaemia. Ther Adv Neurol Disord 2011; 1:12-35. [PMID: 21180567 DOI: 10.1177/1756285608095204] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
There is considerable experimental evidence that hypothermia is neuroprotective and can reduce the severity of brain damage after global or focal cerebral ischaemia. However, despite successful clinical trials for cardiac arrest and perinatal hypoxia-ischaemia and a number of trials demonstrating the safety of moderate and mild hypothermia in stroke, there are still no established guidelines for its use clinically. Based upon a review of the experimental studies we discuss the clinical implications for the use of hypothermia as an adjunctive therapy in global cerebral ischaemia and stroke and make some suggestions for its use in these situations.
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Affiliation(s)
- Bruno P Meloni
- Australian Neuromuscular Research Institute A Block, 1st Floor QEII Medical Centre Nedlands, Western Australia, Australia 6009.
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31
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Zgavc T, Ceulemans AG, Sarre S, Michotte Y, Hachimi-Idrissi S. Experimental and clinical use of therapeutic hypothermia for ischemic stroke: opportunities and limitations. Stroke Res Treat 2011; 2011:689290. [PMID: 21789271 PMCID: PMC3140058 DOI: 10.4061/2011/689290] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Accepted: 05/11/2011] [Indexed: 01/04/2023] Open
Abstract
Stroke remains a disease with a serious impact on quality of life but few effective treatments exist. There is an urgent need to develop and/or improve neuroprotective strategies to combat this. Many drugs proven to be neuroprotective in experimental models fail to improve patient outcome in a clinical setting. An emerging treatment, therapeutic hypothermia (TH), is a promising neuroprotective therapy in stroke management. Several studies with TH in experimental models and small clinical trials have shown beneficial effects. Despite this, implementation into the clinical setting is still lacking due to methodological considerations as well as hypothermia-related complications. This paper discusses the possible opportunities and limitations of the use of TH in animal models and the translation into the clinic.
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Affiliation(s)
- Tine Zgavc
- Department of Pharmaceutical Chemistry and Drug Analysis, Center for Neuroscience, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
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Silasi G, Colbourne F. Unilateral brain hypothermia as a method to examine efficacy and mechanisms of neuroprotection against global ischemia. Ther Hypothermia Temp Manag 2011; 1:87-94. [PMID: 24716998 DOI: 10.1089/ther.2011.0005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Hypothermia, especially applied during ischemia, is the gold-standard neuroprotectant. When delayed, cooling must often be maintained for a day or more to achieve robust, permanent protection. Most animal and clinical studies use whole-body cooling-an arduous technique that can cause systemic complications. Brain-selective cooling may avoid such problems. Thus, in this rat study, we used a method that cools one hemisphere without affecting the contralateral side or the body. Localized brain hypothermia was achieved by flushing cold water through a metal tube attached to the rats' skull. First, in anesthetized rats we measured temperature in the cooled and contralateral hemisphere to demonstrate selective unilateral cooling. Subsequent telemetry recordings in awake rats confirmed that brain cooling did not cause systemic hypothermia during prolonged treatment. Additionally, we subjected rats to transient global ischemia and after recovering from anesthesia they remained at normothermia or had their right hemisphere cooled for 2 days (∼32°C-33°C). Hypothermia significantly lessened CA1 injury and microglia activation on the right side at 1 and 4 week survival times. Near-complete injury and a strong microglia response occurred in the left (normothermic) hippocampus as occurred in both hippocampi of the untreated group. Thus, this focal cooling method is suitable for evaluating the efficacy and mechanisms of hypothermic neuroprotection in global ischemia models. This method also has advantages over many current systemic cooling protocols in rodents, namely: (1) lower cost, (2) simplicity, (3) safety and suitability for long-term cooling, and (4) an internal control-the normothermic hemisphere.
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Affiliation(s)
- Gergely Silasi
- 1 Centre for Neuroscience, University of Alberta , Edmonton, AB, Canada
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Yang B, Strong R, Sharma S, Brenneman M, Mallikarjunarao K, Xi X, Grotta JC, Aronowski J, Savitz SI. Therapeutic time window and dose response of autologous bone marrow mononuclear cells for ischemic stroke. J Neurosci Res 2011; 89:833-9. [PMID: 21412816 DOI: 10.1002/jnr.22614] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 12/28/2010] [Accepted: 01/11/2011] [Indexed: 11/12/2022]
Abstract
Although mononuclear cells (MNCs) from bone marrow are being investigated in phase I clinical trials in stroke patients, dose response, therapeutic time window, and biodistribiton have not been well-characterized in animal stroke models. Long Evans rats underwent common carotid artery/middle cerebral artery occlusion (CCA/MCAo) and 24 hr later were randomized to receive saline IV or a bone marrow aspiration followed by an IV infusion of autologous separated MNCs (1 million, 10 million, or 30 million cells/kg). In another experiment, rats underwent CCAo/MCAo and were randomized at 24 hr, 72 hr, or 7 days after stroke to receive a saline injection or 10 million/kg MNCs. All animals were evaluated on the cylinder and corner tests up to 28 days. MNCs were tracked using Q-dot nanocrystals to monitor biodistribution. Animals treated with MNCs at 10 million and 30 million cells/kg at 24 hr after stroke had significant reductions in neurological deficits and lesion size compared with saline controls or animals treated with 1 million cells/kg. There was no difference in neurological deficits in the 10 and 30 million cell/kg groups at 28 days. Animals treated with MNCs at 72 hr but not at 7 days showed a significant reduction in neurological deficits by 28 days. Labeled MNCs were found in the brain, spleen, lung, liver, and kidney at 1 hr and exponentially decreased over the ensuing week. In conclusion, we found a maximum reduction in neurological deficits at 10 and 30 million cells/kg and a therapeutic time window up to 72 hr after stroke. © 2011 Wiley-Liss, Inc.
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Affiliation(s)
- Bing Yang
- Department of Neurology, University of Texas Medical School at Houston, Houston, TX 77030, USA
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Kallmünzer B, Kollmar R. Temperature Management in Stroke – an Unsolved, but Important Topic. Cerebrovasc Dis 2011; 31:532-43. [DOI: 10.1159/000324621] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Accepted: 01/21/2011] [Indexed: 11/19/2022] Open
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Childs C, Wieloch T, Lecky F, Machin G, Harris B, Stocchetti N. Report of a consensus meeting on human brain temperature after severe traumatic brain injury: its measurement and management during pyrexia. Front Neurol 2010; 1:146. [PMID: 21206519 PMCID: PMC3009434 DOI: 10.3389/fneur.2010.00146] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Accepted: 11/01/2010] [Indexed: 01/16/2023] Open
Abstract
Temperature disturbances are common in patients with severe traumatic brain injury. The possibility of an adaptive, potentially beneficial role for fever in patients with severe brain trauma has been dismissed, but without good justification. Fever might, in some patients, confer benefit. A cadre of clinicians and scientists met to debate the clinically relevant, but often controversial issue about whether raised brain temperature after human traumatic brain injury (TBI) should be regarded as "good or bad" for outcome. The objective was to produce a consensus document of views about current temperature measurement and pyrexia treatment. Lectures were delivered by invited speakers with National and International publication track records in thermoregulation, neuroscience, epidemiology, measurement standards and neurocritical care. Summaries of the lectures and workshop discussions were produced from transcriptions of the lectures and workshop discussions. At the close of meeting, there was agreement on four key issues relevant to modern temperature measurement and management and for undergirding of an evidence-based practice, culminating in a consensus statement. There is no robust scientific data to support the use of hypothermia in patients whose intracranial pressure is controllable using standard therapy. A randomized clinical trial is justified to establish if body cooling for control of pyrexia (to normothermia) vs moderate pyrexia leads to a better patient outcome for TBI patients.
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Affiliation(s)
- Charmaine Childs
- Yong Loo Lin School of Medicine, National University of SingaporeSingapore
| | - Tadeusz Wieloch
- Laboratory for Experimental Brain Research, Wallenberg Centre for NeuroscienceLund, Sweden
| | - Fiona Lecky
- Trauma Audit Research Network, Salford Royal NHS Foundation Trust, University of ManchesterGreater Manchester, UK
| | - Graham Machin
- Temperature Group, National Physical LaboratoryMiddlesex, UK
| | - Bridget Harris
- School of Clinical Sciences and Community Health, Royal Infirmary, The University of EdinburghEdinburgh, UK
| | - Nino Stocchetti
- Terapia Intensiva Neuroscienze, Ospedale Policlinico, Istituiti di Ricovero e Cura a Carattere ScientificoMilano, Italy
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Luckl J, Baker W, Sun ZH, Durduran T, Yodh AG, Greenberg JH. The biological effect of contralateral forepaw stimulation in rat focal cerebral ischemia: a multispectral optical imaging study. FRONTIERS IN NEUROENERGETICS 2010; 2. [PMID: 20725601 PMCID: PMC2922941 DOI: 10.3389/fnene.2010.00019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Accepted: 07/05/2010] [Indexed: 11/22/2022]
Abstract
Our group has already published the possible neuroprotective effect of contralateral forepaw stimulation in temporary focal ischemia in a study. However, the background is still unclear. In the present study we investigated the possible mechanism by monitoring focal ischemia with multispectral [laser speckle, imaging of intrinsic signals (OIS)] imaging. Sprague–Dawley rats were prepared using 1.2% isoflurane anesthesia. The middle cerebral artery was occluded by photothrombosis (4 mW) and the common carotid artery was ligated permanently. Physiological variables were constantly monitored during the experiment. A 6 × 6 mm area centered 3 mm posterior and 4 mm lateral to Bregma was thinned for laser speckle and OIS imaging. Nine circular regions of interests (0.3 mm in diameter) were evenly spaced on the speckle contrast image for the analysis of peri-infarct flow transients, blood flow, and metabolic changes. Both the sham (n = 7) and forepaw-stimulated animals (n = 7) underwent neurological examinations 24 h after ischemia at which point all animals were sacrificed and the infarct size was determined by triphenyltetrazolium chloride. The physiological variables were in normal range and the experimental protocol did not cause significant differences between groups. Both the neurological scores (sham: 3.6 ± 1.7, stimulated: 4.3 ± 1.4) and the infarct volume (sham: 124 ± 39 mm3, stimulated: 147 ± 47 mm3) did not show significant differences between groups. The forepaw stimulation did not increase the intra-ischemic flow neither over the penumbral or the peri-ischemic area. However, the hemoglobin transients related metabolic load (CMRO2) was significantly lower (p < 0.001) while the averaged number of hyperemic flow transients were significantly (p = 0.013) higher in the forepaw (sham: 3.5 ± 2.2, stimulated: 7.0 ± 2.3) stimulated animals.
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Affiliation(s)
- Janos Luckl
- Department of Neurology, University of Pennsylvania Philadelphia, PA, USA
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37
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Abstract
Therapeutic hypothermia is a means of neuroprotection well established in the management of acute ischemic brain injuries such as anoxic encephalopathy after cardiac arrest and perinatal asphyxia. As such, it is the only neuroprotective strategy for which there is robust evidence for efficacy. Although there is overwhelming evidence from animal studies that cooling also improves outcome after focal cerebral ischemia, this has not been adequately tested in patients with acute ischemic stroke. There are still some uncertainties about crucial factors relating to the delivery of hypothermia, and the resolution of these would allow improvements in the design of phase III studies in these patients and improvements in the prospects for successful translation. In this study, we discuss critical issues relating first to the targets for therapy including the optimal depth and duration of cooling, second to practical issues including the methods of cooling and the management of shivering, and finally, of factors relating to the design of clinical trials. Consideration of these factors should inform the development of strategies to establish beyond doubt the place of hypothermia in the management of acute ischemic stroke.
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Kollmar R, Schwab S. Hypothermia in Focal Ischemia: Implications of Experiments and Experience. J Neurotrauma 2009; 26:377-86. [DOI: 10.1089/neu.2008.0564] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Rainer Kollmar
- Department of Neurology, University of Erlangen-Nurnberg, Erlangen, Germany
| | - Stefan Schwab
- Department of Neurology, University of Erlangen-Nurnberg, Erlangen, Germany
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40
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Abstract
Induced hypothermia after ischemic stroke is a promising neuroprotective therapy and is the most potent in pre-clinical models. Technological limitations and homeostatic mechanisms that maintain core body temperature, however, have limited the clinical application of hypothermia. Advances in intravascular cooling and successful trials of hypothermia after global cerebral ischemia, such as in cardiac arrest and neonatal asphyxia, have renewed interest in hypothermia for stroke.
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Affiliation(s)
- Thomas M Hemmen
- Department of Neuroscience, University of California, San Diego, California 92103-8466, USA.
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Theodorsson A, Holm L, Theodorsson E. Hypothermia-induced increase in galanin concentrations and ischemic neuroprotection in the rat brain. Neuropeptides 2008; 42:79-87. [PMID: 18045686 DOI: 10.1016/j.npep.2007.09.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2007] [Revised: 08/28/2007] [Accepted: 09/28/2007] [Indexed: 11/19/2022]
Abstract
The effects of hypothermia on galanin concentrations and the relation between ischemic brain lesions, hypothermia and galanin concentrations in a transient and focal rat stroke model were investigated in order to elucidate whether hypothermia-induced alterations in galanin concentrations could constitute a part of the established neuroprotective effect of hypothermia. Female rats were allocated to normothermia (37 degrees C) or hypothermia (33 degrees C) treatments during a 60 min microclip middle cerebral artery occlusion. The ischemic lesions were visualized after observation periods of 2 or 7 days and the concentration of galanin measured by radioimmunoassay in extracts of punch biopsies from both the lesioned and the contralateral control hemisphere. Hypothermia-induced an overall increase in the concentrations of immunoreactive galanin (p<0.001). The elevated galanin levels were predominantly found in the non-ischemic control hemisphere, in the hippocampus, thalamus and the posterior part of parietal cortex. The galanin concentrations were lower in the ischemic hemisphere in both the normo- and hypothermic animals compared to the corresponding contra lateral intact hemisphere (p=0.049). The factor of time, 2 respectively 7 days, did not show any significant difference regarding the galanin concentrations (p=0.844). Multivariate analyses of variance revealed significant effect of ischemia on the size of the ischemic brain lesions (p=0.001) but no overall effect of temperature when data from both 2 and 7 days observation periods were analyzed together. The ischemic lesions were generally larger at 33 degrees after 2 days (p=0.230). Prolonged observation time of 7 days resulted in a significant reduction of the ischemic brain lesion (p=0.011) with smaller ischemic lesions in the hypothermic group. Our data support the notion that hypothermia-induced increase in the tissue concentrations of galanin in the brain are the result of changes from optimal homeostatic conditions - the hypothermia-induced stress - rather than the ischemia/re-perfusion lesion induced changes in galanin concentrations. Hypothermia-induced elevation in galanin concentration is therefore not likely to be amongst the major protective mechanisms of hypothermia.
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Affiliation(s)
- Annette Theodorsson
- Department of Biomedicine and Surgery, IBK/Clinical Chemistry, Division of Clinical Chemistry, University Hospital, SE-581 85 Linkoping, Sweden.
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Hu WW, Du Y, Li C, Song YJ, Zhang GY. Neuroprotection of hypothermia against neuronal death in rat hippocampus through inhibiting the increased assembly of GluR6-PSD95-MLK3 signaling module induced by cerebral ischemia/reperfusion. Hippocampus 2008; 18:386-97. [PMID: 18172894 DOI: 10.1002/hipo.20402] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Kainate receptor containing GluR6 subunit (KAR) is involved in the neuronal cell death induced by cerebral ischemia/reperfusion (I/R). Hypothermia is an effective neuroprotectant in brain ischemia, whereas the neuroprotective mechanisms have not been clearly established. The present study was set out to examine whether hypothermia would cause the alternation of the assembly of the GluR6-PSD95-MLK3 signaling module and the activation of c-Jun N-terminal kinase (JNK) pathway through KAR. Hypothermia (32 degrees C) was induced 10 min before ischemia and was maintained for 3 h after ischemia. Our results indicated that hypothermia could inhibit the assembly of GluR6-PSD95-MLK3 signaling module and suppressed the activation of MLK3, MKK4/7, and JNK3. The inhibition of JNK3 activation by hypothermia diminished the phosphorylation of the transcription factor c-Jun and downregulated FasL expression in hippocampal CA1. Meanwhile, the inhibition of JNK3 activation by hypothermia attenuated bax translocation, the release of cytochrome c, and the activation of caspase-3 in CA1 subfields. Both GluR6 antagonist NS102 and GluR6 antisense oligodeoxynucleotides partly blocked the aforementioned effects of hypothermia, which was further confirmed by histology. Taken together, our results strongly suggest that hypothermia decreased the increased assembly of the GluR6-PSD95-MLK3 signaling module and the activation of JNK pathway induced by I/R through KAR, which gave a new insight into the ischemic therapy.
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Affiliation(s)
- Wei-Wei Hu
- Research Center for Biochemistry and Molecular Biochemistry and Jiangsu Key Laboratory of Brain Disease Bioinformation, Xuzhou Medical College, Xuzhou, People's Republic of China
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Kurasako T, Zhao L, Pulsinelli WA, Nowak TS. Transient cooling during early reperfusion attenuates delayed edema and infarct progression in the Spontaneously Hypertensive Rat. Distribution and time course of regional brain temperature change in a model of postischemic hypothermic protection. J Cereb Blood Flow Metab 2007; 27:1919-30. [PMID: 17429346 DOI: 10.1038/sj.jcbfm.9600492] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The temperature threshold for protection by brief postischemic cooling was evaluated in a model of transient focal ischemia in the Spontaneously Hypertensive Rat, using an array of epidural probes to monitor regional brain temperatures. Rats were subjected to 90 mins tandem occlusion of the right middle cerebral artery (MCA) and common carotid artery. Systemic cooling to 32 degrees C was initiated 5 mins before recirculation, with simultaneous brain cooling to temperatures ranging from 28 degrees C to 32 degrees C within the MCA territory by means of a temperature-controlled saline drip. Rewarming was initiated at 2 h recirculation and was complete within 30 mins. Tissue damage and edema volume showed clear temperature-dependent reductions when evaluated at 3 days survival, with no protection evident in the group at 32 degrees C but progressive effects on both parameters after deeper cooling. A particularly striking effect was the essentially complete elimination of edema progression between 1 and 3 days. Temperature at distal sites within the MCA territory better predicted reductions in lesion volume, indicating that protection required effective cooling of the penumbral regions destined to be spared. These results show that even brief cooling can be highly protective when initiated at the time of recirculation after focal ischemia, but indicate a substantially lower temperature threshold for hypothermic protection than has been reported for other strains, occlusion methods, and cooling durations.
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Affiliation(s)
- Toshiaki Kurasako
- Department of Neurology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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Zweifler RM, Voorhees ME, Mahmood MA, Alday DD. Induction and maintenance of mild hypothermia by surface cooling in non-intubated subjects. J Stroke Cerebrovasc Dis 2007; 12:237-43. [PMID: 17903934 DOI: 10.1016/j.jstrokecerebrovasdis.2003.09.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2002] [Revised: 05/09/2003] [Accepted: 06/04/2003] [Indexed: 11/24/2022] Open
Abstract
Mild induced hypothermia holds promise as an effective therapy for acute ischemic stroke. We developed a novel strategy to rapidly induce and maintain mild hypothermia in unanesthetized, non-intubated subjects as a model for the treatment of acute stroke patients. We induced and maintained mild hypothermia (tympanic membrane temperature 34 degrees C-35 degrees C) for over 5 hours in 10 healthy volunteers. All subjects received 1000 mg of acetaminophen orally and meperidine intravenously for comfort and suppression of shivering. In phase 1, subjects (n=5) were cooled using Arctic Sun Energy Transfer Pads (Medivance, Inc., Louisville, CO) with manual temperature control. In phase 2, subjects (n=5) were cooled using the Arctic Sun Energy Transfer Pads connected to the Arctic Sun Model 200 Temperature control module (Medivance, Inc.). Core temperatures were measured at the tympanic membrane and rectum. All subjects reached the target tympanic temperature range. The mean time to reach a tympanic temperature of 35 degrees C was 90+/-53 minutes (1.4 degrees C/hour) in phase 2. The most common side effect was nausea, observed in 30% of subjects. There was no statistically significant change in heart rate, blood oxygenation, or diastolic blood pressure compared with baseline; systolic blood pressure was significantly elevated for the 180 minute time point only (140+/-20 mm Hg v 122+/-13 mm Hg; P = .042). We developed a method to rapidly and comfortably induce and maintain mild hypothermia in unanesthetized, non-intubated humans. Further study to optimize the pharmacologic inhibition of thermoregulation and to assess tolerability over longer durations is warranted.
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Shrivastava D, Roemer RB. Readdressing the issue of thermally significant blood vessels using a countercurrent vessel network. J Biomech Eng 2006; 128:210-6. [PMID: 16524332 DOI: 10.1115/1.2165693] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A physiologically realistic arterio-venous countercurrent vessel network model consisting of ten branching vessel generations, where the diameter of each generation of vessels is smaller than the previous ones, has been created and used to determine the thermal significance of different vessel generations by investigating their ability to exchange thermal energy with the tissue. The temperature distribution in the 3D network (8178 vessels; diameters from 10 to 1000 microm) is obtained by solving the conduction equation in the tissue and the convective energy equation with a specified Nusselt number in the vessels. The sensitivity of the exchange of energy between the vessels and the tissue to changes in the network parameters is studied for two cases; a high temperature thermal therapy case when tissue is heated by a uniformly distributed source term and the network cools the tissue, and a hypothermia related case, when tissue is cooled from the surface and the blood heats the tissue. Results show that first, the relative roles of vessels of different diameters are strongly determined by the inlet temperatures to those vessels (e.g., as affected by changing mass flow rates), and the surrounding tissue temperature, but not by their diameter. Second, changes in the following do not significantly affect the heat transfer rates between tissue and vessels; (a) the ratio of arterial to venous vessel diameter, (b) the diameter reduction coefficient (the ratio of diameters of successive vessel generations), and (c) the Nusselt number. Third, both arteries and veins play significant roles in the exchange of energy between tissue and vessels, with arteries playing a more significant role. These results suggest that the determination of which diameter vessels are thermally important should be performed on a case-by-case, problem dependent basis. And, that in the development of site-specific vessel network models, reasonable predictions of the relative roles of different vessel diameters can be obtained by using any physiologically realistic values of Nusselt number and the diameter reduction coefficient.
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Affiliation(s)
- Devashish Shrivastava
- Department of Mechanical Engineering, University of Utah, Salt Lake City, UT 84102, USA
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46
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Delgado P, Sahuquillo J, Poca MA, Alvarez-Sabin J. Neuroprotection in malignant MCA infarction. Cerebrovasc Dis 2006; 21 Suppl 2:99-105. [PMID: 16651820 DOI: 10.1159/000091709] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Massive unilateral hemispheric infarction often develops progressive postischemic edema that leads to a malignant course of stroke with mortality of up to 80% with conventional medical therapies. Hypothermia and decompressive hemicraniectomy have shown neuroprotective effects in several animal models of focal transient and permanent MCA occlusion by reducing infarct size and improving neurological outcome. Our aim in this paper was to review the possible mechanisms of both therapies as well as the optimal time window and duration of application of each treatment in animal model and in human malignant MCA infarction reported in the literature.
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Affiliation(s)
- Pilar Delgado
- Department of Neurology, Vall d'Hebron Hospital, Barcelona, Spain.
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47
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Ma D, Hossain M, Chow A, Arshad M, Battson RM, Sanders RD, Mehmet H, Edwards AD, Franks NP, Maze M. Xenon and hypothermia combine to provide neuroprotection from neonatal asphyxia. Ann Neurol 2005; 58:182-93. [PMID: 16049939 DOI: 10.1002/ana.20547] [Citation(s) in RCA: 216] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Perinatal asphyxia can result in neuronal injury with long-term neurological and behavioral consequences. Although hypothermia may provide some modest benefit, the intervention itself can produce adverse consequences. We have investigated whether xenon, an antagonist of the N-methyl-D-aspartate subtype of the glutamate receptor, can enhance the neuroprotection provided by mild hypothermia. Cultured neurons injured by oxygen-glucose deprivation were protected by combinations of interventions of xenon and hypothermia that, when administered alone, were not efficacious. A combination of xenon and hypothermia administered 4 hours after hypoxic-ischemic injury in neonatal rats provided synergistic neuroprotection assessed by morphological criteria, by hemispheric weight, and by functional neurological studies up to 30 days after the injury. The protective mechanism of the combination, in both in vitro and in vivo models, involved an antiapoptotic action. If applied to humans, these data suggest that low (subanesthetic) concentrations of xenon in combination with mild hypothermia may provide a safe and effective therapy for perinatal asphyxia.
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MESH Headings
- Analysis of Variance
- Animals
- Animals, Newborn
- Apoptosis/drug effects
- Apoptosis/physiology
- Asphyxia/prevention & control
- Blotting, Western/methods
- Body Temperature/physiology
- Brain/drug effects
- Brain/pathology
- Caspase 3
- Caspases/metabolism
- Cells, Cultured
- Cerebral Cortex/cytology
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Embryo, Mammalian
- Excitatory Amino Acid Antagonists/pharmacology
- Flow Cytometry/methods
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/radiation effects
- Glucose/deficiency
- Hypothermia
- Hypoxia
- Hypoxia-Ischemia, Brain/physiopathology
- Hypoxia-Ischemia, Brain/therapy
- Immunohistochemistry/methods
- Indoles/pharmacology
- L-Lactate Dehydrogenase/metabolism
- Male
- Mice
- Mice, Inbred BALB C
- Motor Activity/drug effects
- Motor Activity/physiology
- Necrosis/therapy
- Neurons/drug effects
- Neurons/physiology
- Neuroprotective Agents/therapeutic use
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Rats
- Rats, Sprague-Dawley
- Recovery of Function/drug effects
- Temperature
- Time Factors
- Xenon/therapeutic use
- bcl-2-Associated X Protein
- bcl-X Protein
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Affiliation(s)
- Daqing Ma
- Department of Anaesthetics and Intensive Care, Faculty of Medicine, Imperial College London, London, United Kingdom
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Yanamoto H, Xue JH, Miyamoto S, Nagata I, Nakano Y, Murao K, Kikuchi H. Spreading depression induces long-lasting brain protection against infarcted lesion development via BDNF gene-dependent mechanism. Brain Res 2004; 1019:178-88. [PMID: 15306252 DOI: 10.1016/j.brainres.2004.05.105] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2004] [Indexed: 11/17/2022]
Abstract
Preconditioning the rat brain with spreading depression for 48 h induces potent ischemic tolerance (infarct tolerance) after an interval of 12-15 days, consequently reducing the infarcted lesion size in the acute phase following focal cerebral ischemia. However, persistence of the morphological and functional neuroprotection has not yet been proven. We tested whether tolerance-derived neuroprotection against focal cerebral ischemia persists or merely delays the progress of cerebral infarction. Prolonged spreading depression was induced in mice by placing a depolarized focus with intracerebral microinfusion of KCl for 24 h; after intervals of 3, 6, 9 or 12 days, temporary focal ischemia was imposed. In the analysis of the infarcted lesion volume 24 h after ischemia, groups with 6 or 9 day interval demonstrated significantly smaller lesion volume compared to time-matched vehicle control group (P=0.002). Significant reduction in cerebral infarction was also observed at the chronic phase, namely 14 days after ischemia (33% reduction) (P=0.021) accompanied with less severe neurological deficits (38% reduction) (P=0.020). Using this technique, we also investigated if the mice with targeted disruption of a single BDNF allele (heterozygous BDNF-deficient mice) can gain the same potency of tolerance as the wild mice. In the result on infarcted lesion volumes following temporary focal ischemia, potent tolerance developed in the wild type (35% reduction) (P=0.007) but not in the heterozygous BDNF-deficient mice (<19% reduction) (P=0.155), indicating that BDNF expression level following spreading depression is contributing to infarct tolerance development.
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Affiliation(s)
- Hiroji Yanamoto
- Laboratory for Cerebrovascular Disorders, Research Institute of the National Cardio-Vascular Center, 5-7-1 Fujishirodai, Suita 565-8565, Japan.
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Ding Y, Li J, Luan X, Lai Q, McAllister JP, Phillis JW, Clark JC, Guthikonda M, Diaz FG. Local saline infusion into ischemic territory induces regional brain cooling and neuroprotection in rats with transient middle cerebral artery occlusion. Neurosurgery 2004; 54:956-64; discussion 964-5. [PMID: 15046664 DOI: 10.1227/01.neu.0000114513.96704.29] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2003] [Accepted: 11/18/2003] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE The neuroprotective effect of hypothermia has long been recognized. Use of hypothermia for stroke therapy, which is currently being induced by whole-body surface cooling, has been limited primarily because of management problems and severe side effects (e.g., pneumonia). The goal of this study was to determine whether local infusion of saline into ischemic territory could induce regional brain cooling and neuroprotection. METHODS A novel procedure was used to block the middle cerebral artery of rats for 3 hours with a hollow filament and locally infuse the middle cerebral artery-supplied territory with 6 ml cold saline (20 degrees C) for 10 minutes before reperfusion. RESULTS The cold saline infusion rapidly and significantly reduced temperature in cerebral cortex from 37.2 +/- 0.1 to 33.4 +/- 0.4 degrees C and in striatum from 37.5 +/- 0.2 to 33.9 +/- 0.4 degrees C. The significant hypothermia remained for up to 60 minutes after reperfusion. Significant (P < 0.01) reductions in infarct volume (approximately 90%) were evident after 48 hours of reperfusion. In ischemic rats that received the same amount of cold saline systemically through a femoral artery, a mild hypothermia was induced only in the cerebral cortex (35.3 +/- 0.2 degrees C) and returned to normal within 5 minutes. No significant reductions in infarct volume were observed in this group or in the ischemic group with local warm saline infusion or without infusion. Furthermore, brain-cooling infusion significantly (P < 0.01) improved motor behavior in ischemic rats after 14 days of reperfusion. This improvement continued for up to 28 days after reperfusion. CONCLUSION Local prereperfusion infusion effectively induced hypothermia and ameliorated brain injury from stroke. Clinically, this procedure could be used in acute stroke treatment, possibly in combination with intra-arterial thrombolysis or mechanical disruption of clot by means of a microcatheter.
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Affiliation(s)
- Yuchuan Ding
- Department of Neurological Surgery, Wayne State University School of Medicine, Lande Medical Research Building, Room 48, 550 East Canfield, Detroit, MI 48201, USA.
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Pabello NG, Tracy SJ, Keller RW. Protective effects of brief intra- and delayed postischemic hypothermia in a transient focal ischemia model in the neonatal rat. Brain Res 2004; 995:29-38. [PMID: 14644468 DOI: 10.1016/j.brainres.2003.09.065] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hypothermia provides neuroprotection in virtually all animal models of ischemia, including adult stroke models and the neonatal hypoxic-ischemic (HI) model. In these studies, brief periods of hypothermia are examined in a neonatal model employing transient focal ischemia in a 7-day-old rat pup. Pups underwent permanent middle cerebral artery (MCA) occlusion coupled with a temporary (1 h) occlusion of the ipsilateral common carotid artery (CCA). This study included five treatment groups: (1) normothermic (Normo)-brain temperature was maintained at 37 degrees C; (2) intraischemic hypothermia (IntraH)-28 degrees C during the 1-h ischemic period only; (3) postischemic hypothermia (PostH)-28 degrees C for the second hour of reperfusion only; (4) late-onset postischemic hypothermia (LPostH) cooled to 28 degrees C for the fifth and sixth hours of reperfusion only; and (5) Shams. After various times (3 days-6 weeks), the lesion was assessed using 2,3,5-triphenyltetrazolium chloride (TTC) or hematoxylin and eosin (H&E) stains. Intraischemic hypothermia resulted in significant protection in terms of survival, lesion size, and histology. Postischemic hypothermia was not effective in reducing lesion size early after ischemia, but significantly reduced the eventual long-term damage (2-6 weeks). Late-onset postischemic hypothermia did not reduce infarct volume. Therefore, both intraischemic and postischemic hypothermia provided neuroprotection in the neonatal rat, but with different effects on the degenerative time course. While there were no observable differences in simple behaviors or growth, all hypothermic conditions significantly reduced mortality rates. While the protection resulting from intraischemic hypothermia is similar to what is observed in other models, the degree of long-term ischemic protection observed after 1 h of postischemic hypothermia was remarkable and distinct from what has been observed in other adult or neonatal models.
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Affiliation(s)
- Nina G Pabello
- Center for Neuropharmacology and Neuroscience, Albany Medical College MC-136, 47 New Scotland Avenue, Albany, NY 12208, USA
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