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Shen PP, Hou S, Ma D, Zhao MM, Zhu MQ, Zhang JD, Feng LS, Cui L, Feng JC. Cortical spreading depression-induced preconditioning in the brain. Neural Regen Res 2016; 11:1857-1864. [PMID: 28123433 PMCID: PMC5204245 DOI: 10.4103/1673-5374.194759] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Cortical spreading depression is a technique used to depolarize neurons. During focal or global ischemia, cortical spreading depression-induced preconditioning can enhance tolerance of further injury. However, the underlying mechanism for this phenomenon remains relatively unclear. To date, numerous issues exist regarding the experimental model used to precondition the brain with cortical spreading depression, such as the administration route, concentration of potassium chloride, induction time, duration of the protection provided by the treatment, the regional distribution of the protective effect, and the types of neurons responsible for the greater tolerance. In this review, we focus on the mechanisms underlying cortical spreading depression-induced tolerance in the brain, considering excitatory neurotransmission and metabolism, nitric oxide, genomic reprogramming, inflammation, neurotropic factors, and cellular stress response. Specifically, we clarify the procedures and detailed information regarding cortical spreading depression-induced preconditioning and build a foundation for more comprehensive investigations in the field of neural regeneration and clinical application in the future.
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Affiliation(s)
- Ping-Ping Shen
- Institute of Neuroscience Center and Neurology Department, the First Affiliated Hospital of Jilin University, Changchun, Jilin Province, China
| | - Shuai Hou
- Institute of Neuroscience Center and Neurology Department, the First Affiliated Hospital of Jilin University, Changchun, Jilin Province, China
| | - Di Ma
- Institute of Neuroscience Center and Neurology Department, the First Affiliated Hospital of Jilin University, Changchun, Jilin Province, China
| | - Ming-Ming Zhao
- Institute of Neuroscience Center and Neurology Department, the First Affiliated Hospital of Jilin University, Changchun, Jilin Province, China
| | - Ming-Qin Zhu
- Institute of Neuroscience Center and Neurology Department, the First Affiliated Hospital of Jilin University, Changchun, Jilin Province, China
| | - Jing-Dian Zhang
- Institute of Neuroscience Center and Neurology Department, the First Affiliated Hospital of Jilin University, Changchun, Jilin Province, China
| | - Liang-Shu Feng
- Institute of Neuroscience Center and Neurology Department, the First Affiliated Hospital of Jilin University, Changchun, Jilin Province, China
| | - Li Cui
- Institute of Neuroscience Center and Neurology Department, the First Affiliated Hospital of Jilin University, Changchun, Jilin Province, China
| | - Jia-Chun Feng
- Institute of Neuroscience Center and Neurology Department, the First Affiliated Hospital of Jilin University, Changchun, Jilin Province, China
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Non-invasive infra-red therapy (1072 nm) reduces β-amyloid protein levels in the brain of an Alzheimer's disease mouse model, TASTPM. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2013; 123:13-22. [PMID: 23603448 DOI: 10.1016/j.jphotobiol.2013.02.015] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 02/07/2013] [Accepted: 02/25/2013] [Indexed: 12/16/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) is the most prevalent neurodegenerative disease and common cause of dementias in the Western world. This study investigated the expression profile of heat-shock proteins (HSPs) involved in maintaining healthy neurons in the TASTPM AD mouse model, and whether chronic treatment with 1072 nm infra-red (IR1072) modified the expression profiles of HSPs and amyloidopathy in female TASTPM mice. METHODOLOGY/PRINCIPAL FINDINGS Quantitative immunoblotting and immunohistochemistry were used to examine the expression of proteins such as HSPs, phosphorylated tau (tau-P), amyloid precursor protein (APP), β-amyloid1-40 (Aβ), and Aβ1-42. TASTPM mice at 3, 7 and 12 months were investigated as well as female TASTPM mice which had undergone a chronic, 5 month, IR1072 treatment. During the first 12 months of age, a critical period of AD progression, reduced HSP40 and HSP105 were observed. αB-crystallin, Aβ1-42 and tau-P increased over this period, particularly between 3 and 7 months. Chronic IR1072 treatment of female TASTPM mice elicited significant increases in HSP60, 70 and 105 and phosphorylated-HSP27 (P-HSP27) (50-139%), together with a concomitant profound decrease in αB-crystallin, APP, tau-P, Aβ1-40 and Aβ1-42 (43-81%) protein levels at 7 months of age. Furthermore, IR1072 treatment elicited a modest, but significant, reduction in Aβ1-42 plaques in the cerebral cortex. CONCLUSIONS/SIGNIFICANT FINDINGS IR1072 treatment provides a novel non-invasive and safe way to upregulate a panel of stress response proteins in the brain, known to both reduce protein aggregation and neuronal apoptosis. This approach recently entered clinical trials for AD in the USA, and may provide a novel disease modifying therapy for a range of neuropathologies.
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Maneepark M, Srikiatkhachorn A, Bongsebandhu-phubhakdi S. Involvement of AMPA receptors in CSD-induced impairment of LTP in the hippocampus. Headache 2012; 52:1535-45. [PMID: 22862296 DOI: 10.1111/j.1526-4610.2012.02229.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To investigate the alteration of hippocampal long-term plasticity and basal synaptic transmission induced by repetitive cortical spreading depressions (CSDs). BACKGROUND There is a relationship between migraine aura and amnesia attack. CSD, a state underlying migraine attacks, may be responsible for hippocampus-related symptoms. However, the precise role of CSD on hippocampal activity has not been investigated. METHODS Male Wistar rats were divided into CSD and control groups. Repetitive CSDs were induced in vivo by topical application of solid KCl. Forty-five minutes later, the ipsilateral hippocampus was removed, and hippocampal slices were prepared for a series of electrophysiological studies. RESULTS Repetitive CSDs led to a decrease in the magnitude of long-term potentiation in the hippocampus. CSD also reduced hippocampal synaptic efficacy, as shown by a reduction in post-synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor responses. In contrast, the post-synaptic N-methyl-d-aspartate receptor responses remained unchanged. In addition, there were no changes in paired-pulse profiles between the groups, indicating that CSD did not induce any presynaptic alterations. CONCLUSION These findings suggest that a reduction of post-synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor responses is the mechanism responsible for impaired hippocampal long-term potentiation induced by CSD.
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Affiliation(s)
- Montree Maneepark
- Department of Physiology, Faculty of Medicine, Chulalongkorn University, Patumwan, Bangkok, Thailand
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Molecular Alterations Associated with the NMDA Preconditioning-Induced Neuroprotective Mechanism Against Glutamate Cytotoxicity. J Mol Neurosci 2011; 47:519-32. [DOI: 10.1007/s12031-011-9668-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 10/24/2011] [Indexed: 12/13/2022]
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Chen J, Pan H, Lipsky RH, Pérez-Gómez A, Cabrera-Garcia D, Fernández-Sánchez MT, Novelli A, Marini AM. Cellular and molecular responses of cultured neurons to stressful stimuli. Dose Response 2011; 9:416-33. [PMID: 22013403 DOI: 10.2203/dose-response.10-041.marini] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Synaptic function is critical for the brain to process experiences dictated by the environment requiring change over the lifetime of the organism. Experience-driven adaptation requires that receptors, signal transduction pathways, transcription and translational mechanisms within neurons respond rapidly over its lifetime. Adaptive responses communicated through the rapid firing of neurons are dependent upon the integrity and function of synapses. These rapid responses via adaptation underlie the organism's ability to perceive, learn, remember, calculate and plan. Glutamate, the endogenous neurotransmitter required for physiological excitation in the brain, is critically involved in neuronal adaptive responses and in the pathophysiology of neurodegenerative disorders. Using neuronal experimental systems, we will discuss how compounds with low dose effects mediated via glutamate receptors can result either in a neuroprotective or neurotoxic response. Because the brain has evolved to respond rapidly to environmental cues, exposure of neurons to stressful stimuli can result in a pivotal response toward either synaptic adaptation or dysfunction and neuronal cell death. Understanding how neurons adapt to stressful stimuli will provide important clues toward the development of strategies to protect the brain against neurodegeneration.
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Affiliation(s)
- Jun Chen
- Uniformed Services University of the Health Sciences, Department of Neurology and Program in Neuroscience, 4301 Jones Bridge Road, Bethesda, Maryland 20814
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Haghir H, Kovac S, Speckmann EJ, Zilles K, Gorji A. Patterns of neurotransmitter receptor distributions following cortical spreading depression. Neuroscience 2009; 163:1340-52. [DOI: 10.1016/j.neuroscience.2009.07.067] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Revised: 07/24/2009] [Accepted: 07/26/2009] [Indexed: 01/30/2023]
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Neuronal plasticity after ischemic preconditioning and TIA-like preconditioning ischemic periods. Acta Neuropathol 2009; 117:511-23. [PMID: 19084975 DOI: 10.1007/s00401-008-0473-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Revised: 11/29/2008] [Accepted: 12/06/2008] [Indexed: 01/10/2023]
Abstract
Transient ischemic attacks (TIAs) have recently become the center of attention since they are thought to share some characteristics with experimental ischemic preconditioning (IPC). This phenomenon describes the situation that a brief, per se harmless, cerebral ischemic period renders the brain resistant to a subsequent severe and normally damaging ischemia. Preconditioning (PC) is not restricted to the brain but also occurs in other organs. Furthermore, apart from a short ischemia, the PC event may comprise nearly any noxious stimulus which, however, must not exceed the threshold to tissue damage. In the last two decades, our knowledge concerning the underlying molecular basis of PC has substantially grown and there is hope to potentially imitate the induction of an endogenous neuroprotective state in patients with a high risk of cerebral ischemia. While, at present, there is virtually no neuropathological data on changes after TIAs or TIA-like PC ischemic periods in human brains, the following review will briefly summarize the current knowledge of plastic neuronal changes after PC in animal models, still awaiting their detection in the human brain.
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A new model for the study of high-K+-induced preconditioning in cultured neurones: Role of N-methyl-d-aspartate and α7-nicotinic acetylcholine receptors. J Neurosci Methods 2009; 177:311-6. [DOI: 10.1016/j.jneumeth.2008.10.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Revised: 10/10/2008] [Accepted: 10/14/2008] [Indexed: 11/24/2022]
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Dirnagl U, Meisel A. Endogenous neuroprotection: mitochondria as gateways to cerebral preconditioning? Neuropharmacology 2008; 55:334-44. [PMID: 18402985 DOI: 10.1016/j.neuropharm.2008.02.017] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2007] [Revised: 02/24/2008] [Accepted: 02/26/2008] [Indexed: 01/06/2023]
Abstract
From single to multicellular organisms, protective mechanisms have evolved against endogenous and exogenous noxious stimuli. Preconditioning paradigms, in which stimulation below the threshold of injury results in subsequent protection of the brain, have played an important role in elucidating such endogenous protective mechanisms. Consequently, over the past decades numerous signaling pathways have been discovered by which the brain senses and reacts to such insults as neurotoxins, substrate deprivation, or inflammation. Research on preconditioning is aimed at understanding endogenous neuroprotection to boost it, or to supplement its effectors therapeutically once damage to the brain has occurred, such as after stroke or brain trauma. Another goal of establishing preconditioning protocols is to induce endogenous neuroprotection in anticipation of incipient brain damage. Currently several endogenous neuroprotectants are being investigated in controlled clinical trials. In the present review we will give a short overview on the signals, sensors, transducers, and effectors of endogenous neuroprotection. We will first focus on common mechanisms, on which pathways of endogenous neuroprotection converge, and in particular on mitochondria, which may be considered master integrators of endogenous neuroprotection. We will then discuss various applications of preconditioning, including pharmacological and anesthetic preconditioning, as well as postconditioning, and explore the prospects of endogenous neuroprotective therapeutic approaches.
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Affiliation(s)
- Ulrich Dirnagl
- Department of Experimental Neurology, Center for Stroke Research Berlin, Berlin, Germany.
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Obrenovitch TP. Molecular physiology of preconditioning-induced brain tolerance to ischemia. Physiol Rev 2008; 88:211-47. [PMID: 18195087 DOI: 10.1152/physrev.00039.2006] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Ischemic tolerance describes the adaptive biological response of cells and organs that is initiated by preconditioning (i.e., exposure to stressor of mild severity) and the associated period during which their resistance to ischemia is markedly increased. This topic is attracting much attention because preconditioning-induced ischemic tolerance is an effective experimental probe to understand how the brain protects itself. This review is focused on the molecular and related functional changes that are associated with, and may contribute to, brain ischemic tolerance. When the tolerant brain is subjected to ischemia, the resulting insult severity (i.e., residual blood flow, disruption of cellular transmembrane gradients) appears to be the same as in the naive brain, but the ensuing lesion is substantially reduced. This suggests that the adaptive changes in the tolerant brain may be primarily directed against postischemic and delayed processes that contribute to ischemic damage, but adaptive changes that are beneficial during the subsequent test insult cannot be ruled out. It has become clear that multiple effectors contribute to ischemic tolerance, including: 1) activation of fundamental cellular defense mechanisms such as antioxidant systems, heat shock proteins, and cell death/survival determinants; 2) responses at tissue level, especially reduced inflammatory responsiveness; and 3) a shift of the neuronal excitatory/inhibitory balance toward inhibition. Accordingly, an improved knowledge of preconditioning/ischemic tolerance should help us to identify neuroprotective strategies that are similar in nature to combination therapy, hence potentially capable of suppressing the multiple, parallel pathophysiological events that cause ischemic brain damage.
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Affiliation(s)
- Tihomir Paul Obrenovitch
- Division of Pharmacology, School of Life Sciences, University of Bradford, Bradford, United Kingdom.
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Sachs M, Pape HC, Speckmann EJ, Gorji A. The effect of estrogen and progesterone on spreading depression in rat neocortical tissues. Neurobiol Dis 2007; 25:27-34. [PMID: 17008106 DOI: 10.1016/j.nbd.2006.08.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Revised: 08/07/2006] [Accepted: 08/15/2006] [Indexed: 11/21/2022] Open
Abstract
Although gender differences in the incidence of migraine with aura appear to be related to high circulating levels of ovarian hormones, the underlying mechanisms are not yet fully understood. Several studies have suggested a major role for spreading depression (SD) in the pathogenesis and symptomatology of migraine with aura. To investigate a possible role of SD in the association of high female hormones and attacks of migraine with aura, the effects of beta-estradiol and progesterone on SD were studied in rat neocortical tissues. Application of both hormones enhanced the repetition rate as well as the amplitude of SD in neocortical slices treated with hypotonic artificial cerebrospinal fluid. beta-Estradiol and progesterone also dose dependently increased the amplitude of SD induced by KCl microinjection. Both hormones exhibited a pronounced, persisting, and significant enhancement of long-term potentiation of the field excitatory postsynaptic potential in the neocortical tissues. The changes in SD characteristics in the presence of estrogen and progesterone may responsible for increased migraine with aura attacks associated by high female hormones. These hormones may exert their effects on SD via facilitation of synaptic transmission.
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Affiliation(s)
- Martin Sachs
- Institut für Physiologie I, Westfälische Wilhelms-Universität Münster, Robert-Koch-Strasse 27a, 48149 Münster, Germany
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Marini AM, Jiang X, Wu X, Pan H, Guo Z, Mattson MP, Blondeau N, Novelli A, Lipsky RH. Preconditioning and neurotrophins: a model for brain adaptation to seizures, ischemia and other stressful stimuli. Amino Acids 2006; 32:299-304. [PMID: 16998712 DOI: 10.1007/s00726-006-0414-y] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2005] [Accepted: 08/09/2006] [Indexed: 01/16/2023]
Abstract
The amino acid glutamate, the major excitatory neurotransmitter in the central nervous system, activates receptors coupled to calcium influx. Excessive activation of glutamate receptors in conditions such as severe epileptic seizures or stroke can kill neurons in a process called excitotoxicity. However, subtoxic levels of activation of the N-methyl-D-aspartate (NMDA) type of glutamate receptor elicit adaptive responses in neurons that enhance their ability to withstand more severe stress. A variety of stimuli induce adaptive responses to protect neurons. For example, sublethal ischemic episodes or a mild epileptic insult can protect neurons in a process referred to as tolerance. The molecular mechanisms that protect neurons by these different stressful stimuli are largely unknown but they share common features such as the transcription factor, nuclear factor kappa B (NF-kappaB), which is activated by ischemic and epileptic preconditioning as well as exposure to subtoxic NMDA concentrations. In this article, we describe stress-induced neuroprotective mechanisms highlighting the role of brain-derived neurotrophic factor (BDNF), a protein that plays a crucial role in neuronal survival and maintenance, neurogenesis and learning and memory.
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Affiliation(s)
- A M Marini
- Department of Neurology and Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
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Bradford A, Barlow A, Chazot PL. Probing the differential effects of infrared light sources IR1072 and IR880 on human lymphocytes: evidence of selective cytoprotection by IR1072. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2005; 81:9-14. [PMID: 16046143 DOI: 10.1016/j.jphotobiol.2005.05.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2005] [Revised: 05/24/2005] [Accepted: 05/24/2005] [Indexed: 10/25/2022]
Abstract
Light therapy, both laser and LED, have been shown to provide clinical benefit in many therapeutic arenas. The effects of IR1072 and IR880 were investigated, using a range of single and multiple irradiation protocols, for their effect on freshly prepared human lymphocytes stimulated with phytohemagglutinin. Viable cell numbers remained significantly higher after irradiation with IR1072 and were significantly lower after IR880 irradiation compared to untreated controls, following a daily single irradiation over a 5-day period. Cell numbers were significantly higher after pre-treatment with IR1072 and exposure to UVA, compared to cells treated with UVA only. Cells irradiated twice on Day 3 post-harvest with various wavebands confirm on Day 5, an increase in % cell viability after IR1072, and IR1072 alternating with IR1268 irradiation, and a decrease in % cell viability after IR880 irradiation alone. Further, wavebands tested displayed no significant differences compared to the control. Cells were collected after exposure on Days 3 and 5 with IR1072 and IR880 treatments and protein levels were compared using quantitative immunoblotting probed with an anti-iNOS antibody. Following IR1072, but not IR880, treatment there was a 4.9+/-2.1-fold higher iNOS protein expression in treated cells compared to the control on Day 5 post-treatment.
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Affiliation(s)
- Andrea Bradford
- School of Biological and Biomedical Sciences, University of Durham, South Road, Durham, Tyne & Wear DH1 3LE, United Kingdom
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Zemke D, Smith JL, Reeves MJ, Majid A. Ischemia and ischemic tolerance in the brain: an overview. Neurotoxicology 2005; 25:895-904. [PMID: 15474608 DOI: 10.1016/j.neuro.2004.03.009] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2003] [Accepted: 03/18/2004] [Indexed: 11/24/2022]
Abstract
Stroke is the third leading cause of death and the leading cause of adult disability in the United States. This review outlines the pathways that lead to cell death following stroke, and also summarizes the current literature on the phenomenon of ischemic tolerance. Ischemic tolerance is an endogenous neuroprotective mechanism by which neurons are protected from the deleterious effects of brain ischemia that occur during and after stroke. A better understanding of the processes that lead to cell death after stroke and endogenous neuroprotective mechanisms like ischemic tolerance could help in the development of new treatment strategies for this devastating neurological disease.
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Affiliation(s)
- Daniel Zemke
- Department of Neurology and Ophthalmology, Michigan State University, East Lansing, MI 48824, USA
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Kiss C, Shepard PD, Bari F, Schwarcz R. Cortical spreading depression augments kynurenate levels and reduces malonate toxicity in the rat cortex. Brain Res 2004; 1002:129-35. [PMID: 14988042 DOI: 10.1016/j.brainres.2004.01.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/05/2004] [Indexed: 11/25/2022]
Abstract
Cortical spreading depression (CSD) is characterized by slowly propagating neuronal and astrocytic depolarization, resulting in transient, heightened resistance to subsequent neuronal injury. This study was designed to examine a possible role of the endogenous neuroprotective agent kynurenate (KYNA) in this phenomenon. Unilateral, consecutive CSDs, induced by topical application of 2 M KCl to the cortical surface of adult male rats, resulted in an ipsilateral increase (201-222% compared to controls) in KYNA levels, which was observed in the frontal, parietal and occipital cortex but not in other brain areas. This effect peaked on day 3 after CSD, and KYNA levels returned to normal on day 7. In separate rats, the lesion caused by an intracortical microinjection of the indirect excitotoxin malonate (500 nmol/0.5 microl) on days 1, 3 or 7 after CSD was reduced by 56-75% in the ipsilateral hemisphere. In normal rats, single or multiple injections of the kynurenine 3-hydroxylase inhibitor 4,5-dichlorobenzoylalanine (PNU 156561; 50 mg/kg, i.p.), which results in selective increases in brain KYNA levels, failed to protect cortical neurons against a focal malonate injection. Taken together, these findings indicate that the observed increase in brain KYNA is not responsible for CSD-induced tolerance to malonate-induced neuronal damage.
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Affiliation(s)
- Csaba Kiss
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, PO Box 21247, Baltimore, MD 21228, USA
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Hejmadi MV, Dajas-Bailador F, Barns SM, Jones B, Wonnacott S. Neuroprotection by nicotine against hypoxia-induced apoptosis in cortical cultures involves activation of multiple nicotinic acetylcholine receptor subtypes. Mol Cell Neurosci 2003; 24:779-86. [PMID: 14664825 DOI: 10.1016/s1044-7431(03)00244-6] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Activation of neuronal nicotinic acetylcholine receptors (nAChR) by nicotine has been suggested to protect neurons against a hypoxic insult. The objective of this study was to examine the nature of cell death induced by acute hypoxia in rat primary cortical cultures and the neuroprotective potential of nicotine in ameliorating these processes. Neuronal cell death induced by a 4-h exposure to hypoxia (0.1% O(2)) was apoptotic, as shown by TUNEL staining and assays monitoring DNA strand breaks and caspase-3/7 activity. The presence of nicotine (10 microM) during the hypoxic insult protected a subpopulation of susceptible neurones against DNA damage and apoptosis induced by oxygen deprivation. This protective effect of nicotine was prevented by a 30-min pre-incubation with either 100 nM alpha-bungarotoxin or 1 microM dihydro-beta-erythroidine, but not 1 microM atropine, suggesting that activation of at least two subtypes of nAChR, alpha7 and beta2* nAChR, is involved in mediating nicotine neuroprotection.
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Affiliation(s)
- M V Hejmadi
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK.
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