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The Temporal Pattern, Flux, and Function of Autophagy in Spinal Cord Injury. Int J Mol Sci 2017; 18:ijms18020466. [PMID: 28230791 PMCID: PMC5343998 DOI: 10.3390/ijms18020466] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2016] [Revised: 02/16/2017] [Accepted: 02/17/2017] [Indexed: 12/15/2022] Open
Abstract
Previous studies have indicated that autophagy plays a critical role in spinal cord injury (SCI), including traumatic spinal cord injury (TSCI) and ischemia-reperfusion spinal cord injury (IRSCI). However, while the understanding of mechanisms underlying autophagy in SCI has progressed, there remain several controversial points: (1) temporal pattern results of autophagic activation after SCI are not consistent across studies; (2) effect of accumulation of autophagosomes due to the blockade or enhancement of autophagic flux is uncertain; (3) overall effect of enhanced autophagy remains undefined, with both beneficial and detrimental outcomes reported in SCI literature. In this review, the temporal pattern of autophagic activation, autophagic flux, autophagic cell death, relationship between autophagy and apoptosis, and pharmacological intervention of autophagy in TSCI (contusion injury, compression injury and hemisection injury) and IRSCI are discussed. Types of SCI and severity appear to contribute to differences in outcomes regarding temporal pattern, flux, and function of autophagy. With future development of specific strategies on autophagy intervention, autophagy may play an important role in improving functional recovery in patients with SCI.
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Albayrak S, Atci İB, Kalayci M, Yilmaz M, Kuloglu T, Aydin S, Kom M, Ayden O, Aydin S. Effect of carnosine, methylprednisolone and their combined application on irisin levels in the plasma and brain of rats with acute spinal cord injury. Neuropeptides 2015; 52:47-54. [PMID: 26142757 DOI: 10.1016/j.npep.2015.06.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 06/09/2015] [Accepted: 06/11/2015] [Indexed: 01/02/2023]
Abstract
Spinal cord injury (SCI) might occur to anybody at any time and any age. In its treatment, methylprednisolone (MP) is a first choice worldwide, but there is still no significant breakthrough in truly beneficial treatment due to SCI's complex pathophysiology. We investigated the effect of carnosine, methylprednisolone (MP) and its combination on irisin levels in the plasma, brain and medulla spinalis tissues in SCI using a rat model. The rats were divided into 6 groups: I (Control, saline); II (sham animals with laminectomy without cross-clamping); III (SCI); IV (SCI treated with 150mg/kg carnosine); V (SCI treated with 30mg/kg methylprednisolone); and VI (SCI treated with a combination of carnosine and MP). The animals were given traumatic SCI after laminectomy, using 70-g closing force aneurysm clips (Yasargil FE 721). Irisin concentration was measured by ELISA. The distribution of irisin in brain and spinal cord tissues was examined by immunochemistry. Irisin was mainly expressed in the astrocytes and microglia of brain tissues, and multipolar neurones of the anterior horn of spinal cord tissue in rats of all groups, indicating that irisin is physiologically indispensable. MP and carnosine and the combination of the two, significantly increased irisin in plasma and were accompanied by a significant rise in irisin immunoreactivity of brain and spinal cord tissues of the injured rats compared with control and sham. This finding raises the possibility that methylprednisolone and carnosine regulate the brain and spinal cord tissues in SCI by inducing irisin expression, and may therefore offer a better neurological prognosis.
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Affiliation(s)
- Serdal Albayrak
- Department of Neurosurgery, Elazig Education and Research Hospital, 23100, Elazig, Turkey
| | - İbrahim Burak Atci
- Department of Neurosurgery, Elazig Education and Research Hospital, 23100, Elazig, Turkey
| | - Mehmet Kalayci
- Laboratory of Medical Biochemistry, Elazig Education and Research Hospital, Elazig 23100, Turkey
| | - Musa Yilmaz
- Firat University, School of Medicine, Department of Medical Biochemistry (Firat Hormones Research Group), 23119 Elazig, Turkey
| | - Tuncay Kuloglu
- Firat University, School of Medicine, Department of Histology&Embryology, 23119, Elazig, Turkey
| | - Suna Aydin
- Cardiovascular Surgery- Anatomy, Elazig Education and Research Hospital, 23100, Elazig, Turkey
| | - Mustafa Kom
- Firat University, Veterinary of Medicine, Department of Surgery, Elazig 23119, Turkey
| | - Omer Ayden
- Department of Neurosurgery, Elazig Education and Research Hospital, 23100, Elazig, Turkey
| | - Suleyman Aydin
- Firat University, School of Medicine, Department of Medical Biochemistry (Firat Hormones Research Group), 23119 Elazig, Turkey.
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Yang YHC, Vilin YY, Roberge M, Kurata HT, Johnson JD. Multiparameter screening reveals a role for Na+ channels in cytokine-induced β-cell death. Mol Endocrinol 2014; 28:406-17. [PMID: 24438339 DOI: 10.1210/me.2013-1257] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Pancreatic β-cell death plays a role in both type 1 and type 2 diabetes, but clinical treatments that specifically target β-cell survival have not yet been developed. We have recently developed live-cell imaging-based, high-throughput screening methods capable of identifying factors that modulate pancreatic β-cell death, with the hope of finding drugs that can intervene in this process. In the present study, we used a high-content screen and the Prestwick Chemical Library of small molecules to identify drugs that block cell death resulting from exposure to a cocktail of cytotoxic cytokines (25 ng/mL TNF-α, 10 ng/mL IL-1β, and 10 ng/mL IFN-γ). Data analysis with self-organizing maps revealed that 19 drugs had profiles similar to that of the no cytokine condition, indicating protection. Carbamazepine, an antiepileptic Na(+) channel inhibitor, was particularly interesting because Na(+) channels are not generally considered targets for antiapoptotic therapy in diabetes and because the function of these channels in β-cells has not been well studied. We analyzed the expression and characteristics of Na(+) currents in mature β-cells from MIP-GFP mice. We confirmed the dose-dependent protective effects of carbamazepine and another use-dependent Na(+) channel blocker in cytokine-treated mouse islet cells. Carbamazepine down-regulated the proapoptotic and endoplasmic reticulum stress signaling induced by cytokines. Together, these studies point to Na(+) channels as a novel therapeutic target in diabetes.
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Affiliation(s)
- Yu Hsuan Carol Yang
- Department of Cellular and Physiological Sciences (Y.H.C.Y., J.D.J.), Department of Anesthesiology, Pharmacology, and Therapeutics (Y.Y.V., H.T.K.), and Department of Biochemistry and Molecular Biology (M.R.), University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
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Warren DE, Bickler PE, Clark JP, Gregersen M, Brosnan H, McKleroy W, Gabatto P. Hypothermia and rewarming injury in hippocampal neurons involve intracellular Ca2+ and glutamate excitotoxicity. Neuroscience 2012; 207:316-25. [PMID: 22265728 DOI: 10.1016/j.neuroscience.2011.12.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 12/16/2011] [Accepted: 12/19/2011] [Indexed: 11/18/2022]
Abstract
This study examines the causes of hypothermia and rewarming injury in CA1, CA3, and dentate neurons in rat hippocampal slice cultures. Neuronal death, assessed with propidium iodide or Sytox fluorescence, Fluoro-Jade labeling, and Cresyl Violet staining, depended on the severity and duration of hypothermia. More than 6 h at temperatures less than 12 °C followed by rewarming to 37 °C (profound hypothermia and rewarming, PH/RW) caused swelling and death in large number of neurons in CA1, CA3, and dentate. During PH, [ATP] decreased and [Ca(2+)](I) and extracellular [glutamate] increased, with neuron rupture and nuclear condensation following RW. The data support the hypothesis that neuronal death from PH/RW is excitotoxic, due to ATP loss, glutamate receptor activation and Ca(2+) influx. We found that antagonism of N-methyl-D-aspartate (NMDA) receptors, but not 2-amino-3-(5-methyl-3-oxo-1,2- oxazol-4-yl) propanoic acid or metabotropic glutamate receptors, decreased neuron death and prevented increases in [Ca(2+)](I) caused by PH/RW. Chelating extracellular Ca(2+) decreased PH/RW injury, but inhibiting L- and T-type voltage-gated Ca(2+) channels, K+ channels, Ca(2+) release from the endoplasmic reticulum, and reverse Na(+)/Ca(2+) exchange did not affect the Ca(2+) changes or cell death. We conclude that the mechanism of PH/RW neuronal injury in hippocampal slices primarily involves intracellular Ca(2+) accumulation mediated by NMDA receptors that activates necrotic, but not apoptotic processes.
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Affiliation(s)
- D E Warren
- Department of Anesthesia and Perioperative Care, Parnassus Avenue, University of California, San Francisco, CA 94143-0542, USA
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Fansa I, Altug ME, Melek I, Ucar E, Kontas T, Akcora B, Atik E, Duman T. The Neuroprotective and Anti-inflammatory Effects of Diltiazem in Spinal Cord Ischaemia–Reperfusion Injury. J Int Med Res 2009; 37:520-33. [DOI: 10.1177/147323000903700228] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The protective effects of diltiazem were examined in a rabbit model of spinal cord ischaemia–reperfusion induced by infrarenal aortic occlusion for 30 min. In the diltiazem group ( n = 6), an intravenous infusion (2 μg/kg per min) was started 10 min before ischaemia induction; normal saline solution was infused in the control group ( n = 6). Neurological function was assessed using modified Tarlov criteria 24 h after surgery. Plasma samples were analysed for interleukin (IL)-6 and IL-10. Spinal tissue was analysed for malondialdehyde, nitric oxide and reduced glutathione activities. Tarlov scores of the diltiazem-treated rabbits indicated significantly improved hind-limb motor function compared with the control group. The diltiazem group also had better quantitative and qualitative histopathological findings. Diltiazem infusion significantly reduced IL-6 levels 3 and 24 h after reperfusion compared with the control group. The mean IL-10 level in the diltiazem group was significantly higher than in the control group 24 h after reperfusion. It is concluded that diltiazem has cytoprotective and anti-inflammatory properties, leading to reduced spinal cord injury.
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Affiliation(s)
- I Fansa
- Department of Cardiovascular Surgery, Faculty of Medicine, Mustafa Kemal University, Antakya/Hatay, Turkey
| | - ME Altug
- Department of Surgery, Faculty of Veterinary Medicine, Mustafa Kemal University, Antakya/Hatay, Turkey
| | - I Melek
- Department of Neurology, Faculty of Medicine, Mustafa Kemal University, Antakya/Hatay, Turkey
| | - E Ucar
- Department of Internal Medicine, Faculty of Medicine, Mustafa Kemal University, Antakya/Hatay, Turkey
| | - T Kontas
- Department of Biochemistry, Faculty of Veterinary Medicine, Mustafa Kemal University, Antakya/Hatay, Turkey
| | - B Akcora
- Department of Paediatric Surgery, Faculty of Medicine, Mustafa Kemal University, Antakya/Hatay, Turkey; and
| | - E Atik
- Department of Pathology, Faculty of Medicine, Mustafa Kemal University, Antakya/Hatay, Turkey
| | - T Duman
- Department of Neurology, Faculty of Medicine, Mustafa Kemal University, Antakya/Hatay, Turkey
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Sırlak M, Eryılmaz S, Bahadır Inan M, Sırın YS, Besaltı O, Yazıcıoglu L, Ozcınar E, Erdemlı E, Tasoz R, Elhan AH, Kaya B, Ozyurda U. Effects of carbamazepine on spinal cord ischemia. J Thorac Cardiovasc Surg 2008; 136:1038-1043.e4. [DOI: 10.1016/j.jtcvs.2007.12.068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2007] [Revised: 11/28/2007] [Accepted: 12/18/2007] [Indexed: 01/26/2023]
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Akuzawa S, Kazui T, Shi E, Yamashita K, Bashar AHM, Terada H. Interleukin-1 receptor antagonist attenuates the severity of spinal cord ischemic injury in rabbits. J Vasc Surg 2008; 48:694-700. [DOI: 10.1016/j.jvs.2008.04.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2008] [Revised: 03/23/2008] [Accepted: 04/06/2008] [Indexed: 10/21/2022]
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Shi E, Kazui T, Jiang X, Washiyama N, Yamashita K, Terada H, Bashar AHM. Intrathecal injection of bone marrow stromal cells attenuates neurologic injury after spinal cord ischemia. Ann Thorac Surg 2007; 81:2227-33; discussion 2233-4. [PMID: 16731159 DOI: 10.1016/j.athoracsur.2005.12.056] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2005] [Revised: 12/13/2005] [Accepted: 12/16/2005] [Indexed: 01/13/2023]
Abstract
BACKGROUND It has been shown that transplantation of bone marrow stromal cells (MSCs) into the ischemic brain improves functional outcome. We sought to investigate whether intrathecal injection of MSCs can attenuate neurologic injury of spinal cord ischemia. METHODS Rabbit MSCs were expanded in vitro and were pre-labeled with bromodeoxyuridine. Spinal cord ischemia was induced in rabbits by infrarenal aortic occlusion. Group A and control A were subjected to a 20-minute ischemia and the ischemic duration was extended to 30 minutes in group B and control B. Two days before spinal cord ischemia, 1 x 10(8) MSCs were intrathecally injected into groups A and B, whereas vehicle alone was injected into the control groups. Hind-limb motor function was assessed during a 14-day recovery period with Tarlov criteria, and then histologic examination was performed. RESULTS Marrow stromal cells survived and engrafted into the spinal cord 2 days after transplantation, and more MSCs were found in the lumbar spinal cord (ischemic segment) than in the thoracic spinal cord (nonischemic segment) at 14 days. Compared with their respective control groups, Tarlov scores were significantly higher in both groups A and B (p < 0.05, group A vs control A, at 2, 7, and 14 days; p < 0.05, group B vs control B, at 1, 2, 7, and 14 days, respectively). The number of intact motor neurons was much higher in the two experimental groups (p < 0.01 vs the corresponding control groups, respectively). CONCLUSIONS Intrathecal injection of MSCs attenuates ischemic injury of spinal cord.
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Affiliation(s)
- Enyi Shi
- First Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan
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Shi E, Kazui T, Jiang X, Washiyama N, Yamashita K, Terada H, Bashar AHM. Therapeutic Benefit of Intrathecal Injection of Marrow Stromal Cells on Ischemia-Injured Spinal Cord. Ann Thorac Surg 2007; 83:1484-90. [PMID: 17383362 DOI: 10.1016/j.athoracsur.2006.11.048] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2006] [Revised: 11/14/2006] [Accepted: 11/16/2006] [Indexed: 12/29/2022]
Abstract
BACKGROUND Prophylactic transplantation of marrow stromal cells (MSCs) before spinal cord ischemia has been shown to attenuate neurologic injures. We sought to investigate the therapeutic effect of MSCs on ischemia-injured spinal cord. METHODS Marrow stromal cells were expanded in vitro and prelabeled with bromodeoxyuridine. Spinal cord ischemia was induced in rabbits by infrarenal aortic occlusion for 30 minutes. Four groups were enrolled. About 1 x 10(8) MSCs were intrathecally injected 2 hours (group MSC-2h), 24 hours (group MSC-24h), or 48 hours (group MSC-48h) after spinal cord ischemia, respectively. The control group received intrathecal injection of medium alone. Hind-limb motor function was assessed during a 28-day recovery period with Tarlov criteria, and then histologic examination was performed. RESULTS Marrow stromal cells still could be found in the spinal cord 4 weeks after transplantation. The capillary density in the ventral gray matter was significantly increased in the three MSC-treated groups (p < 0.01 versus control group, respectively). After a 28-day recovery, marked functional improvement was detected in group MSC-2h (from day 1 to 28, p < 0.05, versus control group, respectively) and group MSC-24h (from day 14 to 28, p < 0.05, versus control group, respectively), but not in group MSC-48h. The number of intact motor neurons was much greater in group MSC-2h (p < 0.05, versus control group). CONCLUSIONS Intrathecal injection of MSCs enhances angiogenesis in the host spinal cord and improves the motor functional recovery after spinal cord ischemia. The therapeutic time window is critical for the therapeutic effect of MSCs.
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Affiliation(s)
- Enyi Shi
- Department of Cardiac Surgery, First Affiliated Hospital, China Medical University, Shenyang, China.
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Shi E, Jiang X, Kazui T, Washiyama N, Yamashita K, Terada H, Bashar AHM. Nonviral gene transfer of hepatocyte growth factor attenuates neurologic injury after spinal cord ischemia in rabbits. J Thorac Cardiovasc Surg 2006; 132:941-7. [PMID: 17000308 DOI: 10.1016/j.jtcvs.2006.06.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Revised: 06/11/2006] [Accepted: 06/16/2006] [Indexed: 12/01/2022]
Abstract
OBJECTIVE Paraplegia caused by spinal cord ischemia remains a serious complication after surgical repair of thoracoabdminal aortic aneurysms. Hepatocyte growth factor is a potent angiogenic and neurotrophic factor. We sought to investigate the neuroprotective effect of gene transfer of hepatocyte growth factor on spinal cord ischemia in rabbits. METHODS Human hepatocyte growth factor expression plasmid was combined with hemagglutinating virus of Japan envelope vector. Hemagglutinating virus of Japan envelope vector containing the hepatocyte growth factor gene was injected intrathecally into the experimental rabbits, whereas control vector or saline was given to the control animals. Five days later, spinal cord ischemia was induced by means of infrarenal aortic occlusion for 30 minutes. Hind-limb motor function was assessed during a 14-day recovery period with Tarlov criteria. RESULTS Human hepatocyte growth factor was detected in the cerebrospinal fluid 3 days after gene transfer, and the level peaked on day 5. Compared with the control animals, hepatocyte growth factor gene transfer significantly increased the capillary density in the gray matter and decreased the spinal cord edema. All rabbits pretreated with saline or control vector had hind-limb paraplegia (Tarlov score = 0) 14 days after spinal cord ischemia. However, previous transfection of the hepatocyte growth factor gene remarkably enhanced the Tarlov scores, and 8 of the 9 rabbits showed normal motor function (Tarlov score = 5) after a 14-day recovery period. Histologic examination showed that the intact motor neurons were preserved to a much greater extent in the rabbits transfected with the hepatocyte growth factor gene. CONCLUSION Gene transfer of hepatocyte growth factor attenuates neurologic injury after spinal cord ischemia.
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Affiliation(s)
- Enyi Shi
- First Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan.
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Jiang X, Shi E, Nakajima Y, Sato S. Postconditioning, a series of brief interruptions of early reperfusion, prevents neurologic injury after spinal cord ischemia. Ann Surg 2006; 244:148-53. [PMID: 16794400 PMCID: PMC1570597 DOI: 10.1097/01.sla.0000217608.08582.35] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE We sought to test whether postconditioning, a series of brief mechanical interruptions of reperfusion applied during the onset of reperfusion, can prevent neurologic injury of the spinal cord after transient ischemia. SUMMARY BACKGROUND DATA Ischemia-reperfusion injury of the spinal cord is the principal mechanism leading to the paraplegia after surgery for descending and thoracoabdominal aortic aneurysms. Postconditioning has recently been demonstrated to confer cardioprotection by attenuating reperfusion injury. METHODS Spinal cord ischemia was induced in rabbits by infrarenal aorta occlusion for 25 minutes. Control animals underwent no additional intervention. Two groups of animals underwent postconditioning consisting of 4 or 6 cycles of 1-minute occlusion/1-minute reperfusion, respectively, which were applied 1 minute after the start of reperfusion. In 2 additional groups, 6 cycles of postconditioning started 5 or 10 minutes after the onset of reperfusion, respectively. Hind-limb motor function was assessed during a 10-day recovery period using the modified Tarlov criteria. Histologic examination of the spinal cord was performed, and the number of intact motor neurons was counted. RESULTS Compared with controls, 4 cycles of postconditioning significantly increased the Tarlov score and the number of intact motor neurons. Six cycles of postconditioning did not further improve the neuroprotection. Postconditioning starting 5 minutes after reperfusion still resulted in powerful neuroprotection, but the neuroprotection disappeared completely when postconditioning was delayed for 10 minutes. CONCLUSIONS Postconditioning prevents neurologic injury of the spinal cord after ischemia, and the first few minutes of reperfusion are crucial to neuroprotection by postconditioning.
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Affiliation(s)
- Xiaojing Jiang
- Department of Anesthesiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
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Suzuki K, Kazui T, Terada H, Umemura K, Ikeda Y, Bashar AHM, Yamashita K, Washiyama N, Suzuki T, Ohkura K, Yasuike J. Experimental study on the protective effects of edaravone against ischemic spinal cord injury. J Thorac Cardiovasc Surg 2005; 130:1586-92. [PMID: 16308003 DOI: 10.1016/j.jtcvs.2005.08.049] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Revised: 08/19/2005] [Accepted: 08/26/2005] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Reactive free radical species are thought to be involved in ischemic spinal cord injury. We investigated the effects of edaravone (Mitsubishi Pharma Co, Tokyo, Japan), a free radical scavenger, on spinal ischemia-reperfusion injury in a rabbit model. We also sought to estimate free radicals in the spinal cord using the microdialysis method. METHODS Spinal cord ischemia was induced in New Zealand White rabbits. The animals were then divided into 4 groups. In the first experiment, which was carried out in group A (non-edaravone treated) and group B (edaravone treated), we assessed neurologic function and evaluated spinal cord histopathology. In the second experiment, which was performed in group C (non-edaravone treated) and group D (edaravone treated), we sequentially estimated the level of free radical species in the spinal cord with the microdialysis method. RESULTS In the first experiment group B showed better neurologic function than group A. The number of viable neurons in the spinal cord gray matter was also higher in group B than in group A. The second experiment revealed that the level of free radical species was lower in group D at 75, 90, and 150 minutes after the beginning of reperfusion compared with levels seen in group C. The appearance of free radical species in the latter group was found to have a biphasic pattern, with peaks at 75 and 150 minutes after the beginning of reperfusion. CONCLUSION Edaravone exerted a significant protective effect on the spinal cord against ischemia-reperfusion injury by suppressing the level of free radical species, which was demonstrated with the microdialysis method.
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Affiliation(s)
- Kazuchika Suzuki
- The First Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan.
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