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Intracellular Signaling. Stroke 2022. [DOI: 10.1016/b978-0-323-69424-7.00006-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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2
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Sabet N, Soltani Z, Khaksari M. Multipotential and systemic effects of traumatic brain injury. J Neuroimmunol 2021; 357:577619. [PMID: 34058510 DOI: 10.1016/j.jneuroim.2021.577619] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/07/2021] [Accepted: 05/24/2021] [Indexed: 02/06/2023]
Abstract
Traumatic brain injury (TBI) is one of the leading causes of disability and mortality of people at all ages. Biochemical, cellular and physiological events that occur during primary injury lead to a delayed and long-term secondary damage that can last from hours to years. Secondary brain injury causes tissue damage in the central nervous system and a subsequent strong and rapid inflammatory response that may lead to persistent inflammation. However, this inflammatory response is not limited to the brain. Inflammatory mediators are transferred from damaged brain tissue to the bloodstream and produce a systemic inflammatory response in peripheral organs, including the cardiovascular, pulmonary, gastrointestinal, renal and endocrine systems. Complications of TBI are associated with its multiple and systemic effects that should be considered in the treatment of TBI patients. Therefore, in this review, an attempt was made to examine the systemic effects of TBI in detail. It is hoped that this review will identify the mechanisms of injury and complications of TBI, and open a window for promising treatment in TBI complications.
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Affiliation(s)
- Nazanin Sabet
- Endocrinology and Metabolism Research Center, Institute of Basic and Clinical Physiology Sciences, Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran; Department of Physiology and Pharmacology, Afzalipour Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Zahra Soltani
- Endocrinology and Metabolism Research Center, Institute of Basic and Clinical Physiology Sciences, Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran; Department of Physiology and Pharmacology, Afzalipour Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran.
| | - Mohammad Khaksari
- Physiology Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
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3
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Kim E, Cho S. CNS and peripheral immunity in cerebral ischemia: partition and interaction. Exp Neurol 2021; 335:113508. [PMID: 33065078 PMCID: PMC7750306 DOI: 10.1016/j.expneurol.2020.113508] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/28/2020] [Accepted: 10/08/2020] [Indexed: 02/07/2023]
Abstract
Stroke elicits excessive immune activation in the injured brain tissue. This well-recognized neural inflammation in the brain is not just an intrinsic organ response but also a result of additional intricate interactions between infiltrating peripheral immune cells and the resident immune cells in the affected areas. Given that there is a finite number of immune cells in the organism at the time of stroke, the partitioned immune systems of the central nervous system (CNS) and periphery must appropriately distribute the limited pool of immune cells between the two domains, mounting a necessary post-stroke inflammatory response by supplying a sufficient number of immune cells into the brain while maintaining peripheral immunity. Stroke pathophysiology has mainly been neurocentric in focus, but understanding the distinct roles of the CNS and peripheral immunity in their concerted action against ischemic insults is crucial. This review will discuss stroke-induced influences of the peripheral immune system on CNS injury/repair and of neural inflammation on peripheral immunity, and how comorbidity influences each.
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Affiliation(s)
- Eunhee Kim
- Vivian L. Smith Department of Neurosurgery at University of Texas Health Science Center at Houston, Houston, TX, United States of America
| | - Sunghee Cho
- Burke Neurological Institute, White Plains, NY, United States of America; Feil Brain Mind Research Institute, Weill Cornell Medicine, New York, NY, United States of America.
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Serial Systemic Injections of Endotoxin (LPS) Elicit Neuroprotective Spinal Cord Microglia through IL-1-Dependent Cross Talk with Endothelial Cells. J Neurosci 2020; 40:9103-9120. [PMID: 33051350 DOI: 10.1523/jneurosci.0131-20.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 09/13/2020] [Accepted: 09/17/2020] [Indexed: 12/12/2022] Open
Abstract
Microglia are dynamic immunosurveillance cells in the CNS. Whether microglia are protective or pathologic is context dependent; the outcome varies as a function of time relative to the stimulus, activation state of neighboring cells in the microenvironment or within progression of a particular disease. Although brain microglia can be "primed" using bacterial lipopolysaccharide (LPS)/endotoxin, it is unknown whether LPS delivered systemically can also induce neuroprotective microglia in the spinal cord. Here, we show that serial systemic injections of LPS (1 mg/kg, i.p., daily) for 4 consecutive days (LPSx4) consistently elicit a reactive spinal cord microglia response marked by dramatic morphologic changes, increased production of IL-1, and enhanced proliferation without triggering leukocyte recruitment or overt neuropathology. Following LPSx4, reactive microglia frequently contact spinal cord endothelial cells. Targeted ablation or selective expression of IL-1 and IL-1 receptor (IL-1R) in either microglia or endothelia reveal that IL-1-dependent signaling between these cells mediates microglia activation. Using a mouse model of ischemic spinal cord injury in male and female mice, we show that preoperative LPSx4 provides complete protection from ischemia-induced neuron loss and hindlimb paralysis. Neuroprotection is partly reversed by either pharmacological elimination of microglia or selective removal of IL-1R in microglia or endothelia. These data indicate that spinal cord microglia are amenable to therapeutic reprogramming via systemic manipulation and that this potential can be harnessed to protect the spinal cord from injury.SIGNIFICANCE STATEMENT Data in this report indicate that a neuroprotective spinal cord microglia response can be triggered by daily systemic injections of LPS over a period of 4 d (LPSx4). The LPSx4 regimen induces morphologic transformation and enhances proliferation of spinal cord microglia without causing neuropathology. Using advanced transgenic mouse technology, we show that IL-1-dependent microglia-endothelia cross talk is necessary for eliciting this spinal cord microglia phenotype and also for conferring optimal protection to spinal motor neurons from ischemic spinal cord injury (ISCI). Collectively, these novel data show that it is possible to consistently elicit spinal cord microglia via systemic delivery of inflammogens to achieve a therapeutically effective neuroprotective response against ISCI.
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Kolosowska N, Keuters MH, Wojciechowski S, Keksa-Goldsteine V, Laine M, Malm T, Goldsteins G, Koistinaho J, Dhungana H. Peripheral Administration of IL-13 Induces Anti-inflammatory Microglial/Macrophage Responses and Provides Neuroprotection in Ischemic Stroke. Neurotherapeutics 2019; 16:1304-1319. [PMID: 31372938 PMCID: PMC6985054 DOI: 10.1007/s13311-019-00761-0] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Neuroinflammation is strongly induced by cerebral ischemia. The early phase after the onset of ischemic stroke is characterized by acute neuronal injury, microglial activation, and subsequent infiltration of blood-derived inflammatory cells, including macrophages. Therefore, modulation of the microglial/macrophage responses has increasingly gained interest as a potential therapeutic approach for the ischemic stroke. In our study, we investigated the effects of peripherally administered interleukin 13 (IL-13) in a mouse model of permanent middle cerebral artery occlusion (pMCAo). Systemic administration of IL-13 immediately after the ischemic insult significantly reduced the lesion volume, alleviated the infiltration of CD45+ leukocytes, and promoted the microglia/macrophage alternative activation within the ischemic region, as determined by arginase 1 (Arg1) immunoreactivity at 3 days post-ischemia (dpi). Moreover, IL-13 enhanced the expression of M2a alternative activation markers Arg1 and Ym1 in the peri-ischemic (PI) area, as well as increased plasma IL-6 and IL-10 levels at 3 dpi. Furthermore, IL-13 treatment ameliorated gait disturbances at day 7 and 14 and sensorimotor deficits at day 14 post-ischemia, as analyzed by the CatWalk gait analysis system and adhesive removal test, respectively. Finally, IL-13 treatment decreased neuronal cell death in a coculture model of neuroinflammation with RAW 264.7 macrophages. Taken together, delivery of IL-13 enhances microglial/macrophage anti-inflammatory responses in vivo and in vitro, decreases ischemia-induced brain cell death, and improves sensory and motor functions in the pMCAo mouse model of cerebral ischemia.
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Affiliation(s)
- Natalia Kolosowska
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Meike H. Keuters
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
- Neuroscience Center, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, Helsinki, Finland
| | - Sara Wojciechowski
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Velta Keksa-Goldsteine
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Mika Laine
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Tarja Malm
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Gundars Goldsteins
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jari Koistinaho
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
- Neuroscience Center, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, Helsinki, Finland
- Neuroscience Center, HiLIFE, University of Helsinki, Haartmaninkatu 8, Helsinki, 00290 Finland
| | - Hiramani Dhungana
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
- Neuroscience Center, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, Helsinki, Finland
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Affiliation(s)
- Jaroslaw Aronowski
- From the Department of Neurology, University of Texas Health Science Center, McGovern Medical School, Houston
| | - Meaghan A Roy-O'Reilly
- From the Department of Neurology, University of Texas Health Science Center, McGovern Medical School, Houston
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Vinciguerra A, Cuomo O, Cepparulo P, Anzilotti S, Brancaccio P, Sirabella R, Guida N, Annunziato L, Pignataro G. Models and methods for conditioning the ischemic brain. J Neurosci Methods 2018; 310:63-74. [PMID: 30287283 DOI: 10.1016/j.jneumeth.2018.09.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 09/13/2018] [Accepted: 09/26/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND In the last decades the need to find new neuroprotective targets has addressed the researchers to investigate the endogenous molecular mechanisms that brain activates when exposed to a conditioning stimulus. Indeed, conditioning is an adaptive biological process activated by those interventions able to confer resistance to a deleterious brain event through the exposure to a sub-threshold insult. Specifically, preconditioning and postconditioning are realized when the conditioning stimulus is applied before or after, respectively, the harmul ischemia. AIMS AND RESULTS The present review will describe the most common methods to induce brain conditioning, with particular regards to surgical, physical exercise, temperature-induced and pharmacological approaches. It has been well recognized that when the subliminal stimulus is delivered after the ischemic insult, the achieved neuroprotection is comparable to that observed in models of ischemic preconditioning. In addition, subjecting the brain to both preconditioning as well as postconditioning did not cause greater protection than each treatment alone. CONCLUSIONS The last decades have provided fascinating insights into the mechanisms and potential application of strategies to induce brain conditioning. Since the identification of intrinsic cell-survival pathways should provide more direct opportunities for translational neuroprotection trials, an accurate examination of the different models of preconditioning and postconditioning is mandatory before starting any new project.
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Affiliation(s)
- Antonio Vinciguerra
- Division of Pharmacology, Department of Neuroscience, School of Medicine, "Federico II" University of Naples, Via Pansini, 5, 80131, Naples, Italy
| | - Ornella Cuomo
- Division of Pharmacology, Department of Neuroscience, School of Medicine, "Federico II" University of Naples, Via Pansini, 5, 80131, Naples, Italy
| | - Pasquale Cepparulo
- Division of Pharmacology, Department of Neuroscience, School of Medicine, "Federico II" University of Naples, Via Pansini, 5, 80131, Naples, Italy
| | | | - Paola Brancaccio
- Division of Pharmacology, Department of Neuroscience, School of Medicine, "Federico II" University of Naples, Via Pansini, 5, 80131, Naples, Italy
| | - Rossana Sirabella
- Division of Pharmacology, Department of Neuroscience, School of Medicine, "Federico II" University of Naples, Via Pansini, 5, 80131, Naples, Italy
| | | | | | - Giuseppe Pignataro
- Division of Pharmacology, Department of Neuroscience, School of Medicine, "Federico II" University of Naples, Via Pansini, 5, 80131, Naples, Italy.
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8
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Endogenous Protection from Ischemic Brain Injury by Preconditioned Monocytes. J Neurosci 2018; 38:6722-6736. [PMID: 29946039 DOI: 10.1523/jneurosci.0324-18.2018] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 06/09/2018] [Accepted: 06/18/2018] [Indexed: 12/24/2022] Open
Abstract
Exposure to low-dose lipopolysaccharide (LPS) before cerebral ischemia is neuroprotective in stroke models, a phenomenon termed preconditioning (PC). Although it is well established that LPS-PC induces central and peripheral immune responses, the cellular mechanisms modulating ischemic injury remain unclear. Here, we investigated the role of immune cells in the brain protection afforded by PC and tested whether monocytes may be reprogrammed by ex vivo LPS exposure, thus modulating inflammatory injury after cerebral ischemia in male mice. We found that systemic injection of low-dose LPS induces a Ly6Chi monocyte response that protects the brain after transient middle cerebral artery occlusion (MCAO) in mice. Remarkably, adoptive transfer of monocytes isolated from preconditioned mice into naive mice 7 h after transient MCAO reduced brain injury. Gene expression and functional studies showed that IL-10, inducible nitric oxide synthase, and CCR2 in monocytes are essential for neuroprotection. This protective activity was elicited even if mouse or human monocytes were exposed ex vivo to LPS and then injected into male mice after stroke. Cell-tracking studies showed that protective monocytes are mobilized from the spleen and reach the brain and meninges, where they suppress postischemic inflammation and neutrophil influx into the brain parenchyma. Our findings unveil a previously unrecognized subpopulation of splenic monocytes capable of protecting the brain with an extended therapeutic window and provide the rationale for cell therapies based on the delivery of autologous or allogeneic protective monocytes in patients after ischemic stroke.SIGNIFICANCE STATEMENT Inflammation is a key component of the pathophysiology of the brain in stroke, a leading cause of death and disability with limited therapeutic options. Here, we investigate endogenous mechanisms of protection against cerebral ischemia. Using lipopolysaccharide (LPS) preconditioning (PC) as an approach to induce ischemic tolerance in mice, we found generation of neuroprotective monocytes within the spleen, from which they traffic to the brain and meninges, suppressing postischemic inflammation. Importantly, systemic LPS-PC can be mimicked by adoptive transfer of in vitro-preconditioned mouse or human monocytes at translational relevant time points after stroke. This model of neuroprotection may facilitate clinical efforts to increase the efficacy of BM mononuclear cell treatments in acute neurological diseases such as cerebral ischemia.
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9
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Corrigan F, Arulsamy A, Collins-Praino LE, Holmes JL, Vink R. Toll like receptor 4 activation can be either detrimental or beneficial following mild repetitive traumatic brain injury depending on timing of activation. Brain Behav Immun 2017; 64:124-139. [PMID: 28412141 DOI: 10.1016/j.bbi.2017.04.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 03/30/2017] [Accepted: 04/07/2017] [Indexed: 12/14/2022] Open
Abstract
A history of repeated concussion has been linked to the later development of neurodegeneration, which is associated with the accumulation of hyperphosphorylated tau and the development of behavioral deficits. However, the role that exogenous factors, such as immune activation, may play in the development of neurodegeneration following repeated mild traumatic brain injury (rmTBI) has not yet been explored. To investigate, male Sprague-Dawley rats were administered three mTBIs 5days apart using the diffuse impact-acceleration model to generate ∼100G. Sham animals underwent surgery only. At 1 or 5days following the last injury rats were given the TLR4 agonist, lipopolysaccharide (LPS, 0.1mg/kg), or saline. TLR4 activation had differential effects following rmTBI depending on the timing of activation. When given at 1day post-injury, LPS acutely activated microglia, but decreased production of pro-inflammatory cytokines like IL-6. This was associated with a reduction in neuronal injury, both acutely, with a restoration of levels of myelin basic protein (MBP), and chronically, preventing a loss of both MBP and PSD-95. Furthermore, these animals did not develop behavioral deficits with no changes in locomotion, anxiety, depressive-like behavior or cognition at 3months post-injury. Conversely, when LPS was given at 5days post-injury, it was associated acutely with an increase in pro-inflammatory cytokine production, with an exacerbation of neuronal damage and increased levels of aggregated and phosphorylated tau. At 3months post-injury, there was a slight exacerbation of functional deficits, particularly in cognition and depressive-like behavior. This highlights the complexity of the immune response following rmTBI and the need to understand how a history of rmTBI interacts with environmental factors to influence the potential to develop later neurodegeneration.
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Affiliation(s)
- Frances Corrigan
- Discipline of Anatomy and Pathology, Adelaide Medical School, University of Adelaide, Adelaide, Australia.
| | - Alina Arulsamy
- Discipline of Anatomy and Pathology, Adelaide Medical School, University of Adelaide, Adelaide, Australia
| | - Lyndsey E Collins-Praino
- Discipline of Anatomy and Pathology, Adelaide Medical School, University of Adelaide, Adelaide, Australia
| | - Joshua L Holmes
- Discipline of Anatomy and Pathology, Adelaide Medical School, University of Adelaide, Adelaide, Australia
| | - Robert Vink
- Sansom Institute for Health Research, University of South Australia, Adelaide, Australia
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Cheng Y, Wei Y, Yang W, Cai Y, Chen B, Yang G, Shang H, Zhao W. Ghrelin Attenuates Intestinal Barrier Dysfunction Following Intracerebral Hemorrhage in Mice. Int J Mol Sci 2016; 17:ijms17122032. [PMID: 27929421 PMCID: PMC5187832 DOI: 10.3390/ijms17122032] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 11/10/2016] [Accepted: 11/28/2016] [Indexed: 02/07/2023] Open
Abstract
Intestinal barrier dysfunction remains a critical problem in patients with intracerebral hemorrhage (ICH) and is associated with poor prognosis. Ghrelin, a brain-gut peptide, has been shown to exert protection in animal models of gastrointestinal injury. However, the effect of ghrelin on intestinal barrier dysfunction post-ICH and its possible underlying mechanisms are still unknown. This study was designed to investigate whether ghrelin administration attenuates intestinal barrier dysfunction in experimental ICH using an intrastriatal autologous blood infusion mouse model. Our data showed that treatment with ghrelin markedly attenuated intestinal mucosal injury at both histomorphometric and ultrastructural levels post-ICH. Ghrelin reduced ICH-induced intestinal permeability according to fluorescein isothiocyanate conjugated-dextran (FITC-D) and Evans blue extravasation assays. Concomitantly, the intestinal tight junction-related protein markers, Zonula occludens-1 (ZO-1) and claudin-5 were upregulated by ghrelin post-ICH. Additionally, ghrelin reduced intestinal intercellular adhesion molecule-1 (ICAM-1) expression at the mRNA and protein levels following ICH. Furthermore, ghrelin suppressed the translocation of intestinal endotoxin post-ICH. These changes were accompanied by improved survival rates and an attenuation of body weight loss post-ICH. In conclusion, our results suggest that ghrelin reduced intestinal barrier dysfunction, thereby reducing mortality and weight loss, indicating that ghrelin is a potential therapeutic agent in ICH-induced intestinal barrier dysfunction therapy.
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Affiliation(s)
- Yijun Cheng
- Department of Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
| | - Yongxu Wei
- Department of Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
| | - Wenlei Yang
- Department of Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
| | - Yu Cai
- Department of Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
| | - Bin Chen
- Department of Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
| | - Guoyuan Yang
- Department of Neurology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
- Neuroscience and Neuroengineering Research Center, Med-X Research Institute, Shanghai Jiao Tong University, Shanghai 200030, China.
| | - Hanbing Shang
- Department of Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
| | - Weiguo Zhao
- Department of Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
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Thompson JW, Dawson VL, Perez-Pinzon MA, Dawson TM. Intracellular Signaling. Stroke 2016. [DOI: 10.1016/b978-0-323-29544-4.00006-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Anrather J, Iadecola C, Hallenbeck J. Inflammation and Immune Response. Stroke 2016. [DOI: 10.1016/b978-0-323-29544-4.00010-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Simon RP. Epigenetic modulation of gene expression governs the brain's response to injury. Neurosci Lett 2015; 625:16-9. [PMID: 26739198 DOI: 10.1016/j.neulet.2015.12.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 12/03/2015] [Accepted: 12/11/2015] [Indexed: 10/22/2022]
Abstract
Mild stress from ischemia, seizure, hypothermia, or infection can produce a transient neuroprotected state in the brain. In the neuroprotected state, the brain responds differently to a severe stress and sustains less injury. At the genomic level, the response of the neuroprotected brain to a severe stress is characterized by widespread differential regulation of genes with diverse functions. This reprogramming of gene expression observed in the neuroprotected brain in response to a stress is consistent with an epigenetic model of regulation mediated by changes in DNA methylation and histone modification. Here, we summarize our evolving understanding of the molecular basis for endogenous neuroprotection and review recent findings that implicate DNA methylation and protein mediators of histone modification as epigenetic regulators of the brain's response to injury.
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Affiliation(s)
- Roger P Simon
- Translational Stroke Program, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, USA; Grady Memorial Hospital, Atlanta, GA, USA.
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Breen PP, Buskila Y. Braincubator: an incubation system to extend brain slice lifespan for use in neurophysiology. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2014:4864-7. [PMID: 25571081 DOI: 10.1109/embc.2014.6944713] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In vitro brain slice preparations are instrumental in developing our understanding of the nervous system. However, the current lifespan of an acute brain slice is limited to approximately 6-12 hours. This reduces potential experimentation time and leads to considerable waste of neural tissue. We have designed, developed and tested a novel incubation system capable of extending the lifespan of these brain slices. This is done by controlling the temperature and pH of the artificial cerebral spinal fluid in which the slices are incubated while continuously passing the fluid through a UVC filtration system. This system is capable of maintaining extremely low bacterial levels and significantly extending the brain slice lifespan to at least 24 hours. Brain slice viability was validated through electrophysiological recordings as well as live/dead cell assays.
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15
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Semple BD, Trivedi A, Gimlin K, Noble-Haeusslein LJ. Neutrophil elastase mediates acute pathogenesis and is a determinant of long-term behavioral recovery after traumatic injury to the immature brain. Neurobiol Dis 2014; 74:263-80. [PMID: 25497734 DOI: 10.1016/j.nbd.2014.12.003] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 11/19/2014] [Accepted: 12/01/2014] [Indexed: 12/21/2022] Open
Abstract
While neutrophil elastase (NE), released by activated neutrophils, is a key mediator of secondary pathogenesis in adult models of brain ischemia and spinal cord injury, no studies to date have examined this protease in the context of the injured immature brain, where there is notable vulnerability resulting from inadequate antioxidant reserves and prolonged exposure to infiltrating neutrophils. We thus reasoned that NE may be a key determinant of secondary pathogenesis, and as such, adversely influence long-term neurological recovery. To address this hypothesis, wild-type (WT) and NE knockout (KO) mice were subjected to a controlled cortical impact at post-natal day 21, approximating a toddler-aged child. To determine if NE is required for neutrophil infiltration into the injured brain, and whether this protease contributes to vasogenic edema, we quantified neutrophil numbers and measured water content in the brains of each of these genotypes. While leukocyte trafficking was indistinguishable between genotypes, vasogenic edema was markedly attenuated in the NE KO. To determine if early pathogenesis is dependent on NE, indices of cell death (TUNEL and activated caspase-3) were quantified across genotypes. NE KO mice showed a reduction in these markers of cell death in the injured hippocampus, which corresponded to greater preservation of neuronal integrity as well as reduced expression of heme oxygenase-1, a marker of oxidative stress. WT mice, treated with a competitive inhibitor of NE at 2, 6 and 12h post-injury, likewise showed a reduction in cell death and oxidative stress compared to vehicle-treated controls. We next examined the long-term behavioral and structural consequences of NE deficiency. NE KO mice showed an improvement in long-term spatial memory retention and amelioration of injury-induced hyperactivity. However, volumetric and stereological analyses found comparable tissue loss in the injured cortex and hippocampus independent of genotype. Further, WT mice treated acutely with the NE inhibitor showed no long-term behavioral or structural improvements. Together, these findings validate the central role of NE in both acute pathogenesis and chronic functional recovery, and support future exploration of the therapeutic window, taking into account the prolonged period of neutrophil trafficking into the injured immature brain.
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Affiliation(s)
- Bridgette D Semple
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA 94143, USA; Department of Medicine (Royal Melbourne Hospital), University of Melbourne, Parkville, VIC 3000, Australia.
| | - Alpa Trivedi
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA 94143, USA.
| | - Kayleen Gimlin
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA 94143, USA.
| | - Linda J Noble-Haeusslein
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA 94143, USA; Department of Physical Therapy and Rehabilitation Sciences, University of California San Francisco, San Francisco, CA 94143, USA.
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16
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Abstract
The lifespan of an acute brain slice is approximately 6–12 hours, limiting potential experimentation time. We have designed a new recovery incubation system capable of extending their lifespan to more than 36 hours. This system controls the temperature of the incubated artificial cerebral spinal fluid (aCSF) while continuously passing the fluid through a UVC filtration system and simultaneously monitoring temperature and pH. The combination of controlled temperature and UVC filtering maintains bacteria levels in the lag phase and leads to the dramatic extension of the brain slice lifespan. Brain slice viability was validated through electrophysiological recordings as well as live/dead cell assays. This system benefits researchers by monitoring incubation conditions and standardizing this artificial environment. It further provides viable tissue for two experimental days, reducing the time spent preparing brain slices and the number of animals required for research.
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17
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Bénardais K, Gudi V, Gai L, Neßler J, Singh V, Prajeeth CK, Skripuletz T, Stangel M. Long-term impact of neonatal inflammation on demyelination and remyelination in the central nervous system. Glia 2014; 62:1659-70. [PMID: 24909143 DOI: 10.1002/glia.22706] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 05/21/2014] [Accepted: 05/23/2014] [Indexed: 12/12/2022]
Abstract
Perinatal inflammation causes immediate changes of the blood-brain barrier (BBB) and thus may have different consequences in adult life including an impact on neurological diseases such as demyelinating disorders. In order to determine if such a perinatal insult affects the course of demyelination in adulthood as "second hit," we simulated perinatal bacterial inflammation by systemic administration of lipopolysaccharide (LPS) to either pregnant mice or newborn animals. Demyelination was later induced in adult animals by cuprizone [bis(cyclohexylidenehydrazide)], which causes oligodendrocyte death with subsequent demyelination accompanied by strong microgliosis and astrogliosis. A single LPS injection at embryonic day 13.5 did not have an impact on demyelination in adulthood. In contrast, serial postnatal LPS injections (P0-P8) caused an early delay of myelin removal in the corpus callosum, which was paralleled by reduced numbers of activated microglia. During remyelination, postnatal LPS treatment enhanced early remyelination with a concomitant increase of mature oligodendrocytes. Furthermore, the postnatal LPS challenge impacts the phenotype of microglia since an elevated mRNA expression of microglia related genes such as TREM 2, CD11b, TNF-α, TGF-β1, HGF, FGF-2, and IGF-1 was found in these preconditioned mice during early demyelination. These data demonstrate that postnatal inflammation has long-lasting effects on microglia functions and modifies the course of demyelination and remyelination in adulthood.
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Affiliation(s)
- Karelle Bénardais
- Department of Neurology, Hannover Medical School, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
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Garcia-Bonilla L, Benakis C, Moore J, Iadecola C, Anrather J. Immune mechanisms in cerebral ischemic tolerance. Front Neurosci 2014; 8:44. [PMID: 24624056 PMCID: PMC3940969 DOI: 10.3389/fnins.2014.00044] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Accepted: 02/17/2014] [Indexed: 12/21/2022] Open
Abstract
Stressor-induced tolerance is a central mechanism in the response of bacteria, plants, and animals to potentially harmful environmental challenges. This response is characterized by immediate changes in cellular metabolism and by the delayed transcriptional activation or inhibition of genetic programs that are not generally stressor specific (cross-tolerance). These programs are aimed at countering the deleterious effects of the stressor. While induction of this response (preconditioning) can be established at the cellular level, activation of systemic networks is essential for the protection to occur throughout the organs of the body. This is best signified by the phenomenon of remote ischemic preconditioning, whereby application of ischemic stress to one tissue or organ induces ischemic tolerance (IT) in remote organs through humoral, cellular and neural signaling. The immune system is an essential component in cerebral IT acting simultaneously both as mediator and target. This dichotomy is based on the fact that activation of inflammatory pathways is necessary to establish IT and that IT can be, in part, attributed to a subdued immune activation after index ischemia. Here we describe the components of the immune system required for induction of IT and review the mechanisms by which a reprogrammed immune response contributes to the neuroprotection observed after preconditioning. Learning how local and systemic immune factors participate in endogenous neuroprotection could lead to the development of new stroke therapies.
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Affiliation(s)
- Lidia Garcia-Bonilla
- Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA
| | - Corinne Benakis
- Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA
| | - Jamie Moore
- Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA
| | - Costantino Iadecola
- Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA
| | - Josef Anrather
- Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA
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Easton AS. Neutrophils and stroke – Can neutrophils mitigate disease in the central nervous system? Int Immunopharmacol 2013; 17:1218-25. [DOI: 10.1016/j.intimp.2013.06.015] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 02/15/2013] [Accepted: 06/09/2013] [Indexed: 12/19/2022]
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Sun L, Jin Y, Dong L, Sumi R, Jahan R, Li Z. The neuroprotective effects of Coccomyxa gloeobotrydiformis on the ischemic stroke in a rat model. Int J Biol Sci 2013; 9:811-7. [PMID: 23983614 PMCID: PMC3753445 DOI: 10.7150/ijbs.6734] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/13/2013] [Indexed: 11/05/2022] Open
Abstract
Stroke is a major cause of mortality and the leading cause of permanent disability. In this study, we adopted the classic middle cerebral artery occlusion(MCAO) stroke model to observe the therapeutic effects of coccomyxa gloeobotrydiformis(CGD) on ischemic stroke, and discuss the underlying mechanisms. Low dose (50 mg/kg.day) and high dose (100 mg/kg.day) concentrations of the drug CGD were intragastrically administrated separately for 8 weeks. Infarct volumes, neurologic deficits and degree of stroke-induced brain edema were measured 24 hours after reperfusion. Furthermore, oxidative stress related factors (SOD and MDA), mitochondrial membrane potential, and apoptosis regulatory factors (mitochondrial Cyt-C, Bcl-2, Bax, and caspase-3) were all investigated in this research. We found that CGD attenuated cerebral infarction, brain edema and neurologic deficits; CGD maintained the mitochondrial membrane potential and decreased mitochondrial swelling. It also prevented oxidative damage by reducing MDA and increasing SOD. In addition, CGD could effectively attenuate apoptosis by restoring the level of mitochondrial Cyt C and regulating the expression of Bcl-2, Bax and caspase 3. These results revealed that CGD has a therapeutic effect on ischemic stroke, possibly by inducing mitochondrial protection and anti-apoptotic mechanisms.
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Affiliation(s)
- Luning Sun
- Department of Pathophysiology, College of Basic Medical Science, China Medical University, Shenyang, China
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21
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Ajmone-Cat MA, Mancini M, De Simone R, Cilli P, Minghetti L. Microglial polarization and plasticity: evidence from organotypic hippocampal slice cultures. Glia 2013; 61:1698-711. [PMID: 23918452 DOI: 10.1002/glia.22550] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 05/18/2013] [Accepted: 06/17/2013] [Indexed: 01/24/2023]
Abstract
Increasing evidence indicates that "functional plasticity" is not solely a neuronal attribute but a hallmark of microglial cells, the main brain resident macrophage population. Far from being a univocal phenomenon, microglial activation can originate a plethora of functional phenotypes, encompassing the classic M1 proinflammatory and the alternative M2 anti-inflammatory phenotypes. This concept overturns the popular view of microglial activation as a synonym of neurotoxicity and neurogenesis failure in brain disorders. The characterization of the alternative programs is a matter of intense investigation, but still scarce information is available on the course of microglial activation, on the reversibility of the different commitments and on the capability of preserving molecular memory of previous priming stimuli. By using organotypic hippocampal slice cultures as a model, we developed paradigms of stimulation aimed at shedding light on some of these aspects. We show that persistent stimulation of TLR4 signaling promotes an anti-inflammatory response and microglial polarization toward M2-like phenotype. Moreover, acute and chronic preconditioning regimens permanently affect the capability to respond to a later challenge, suggesting the onset of mechanisms of molecular memory. Similar phenomena could occur in the intact brain and differently affect the vulnerability of mature and newborn neurons to noxious signals.
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Akay C, Yaman H, Oztosun M, Cakir E, Yildirim AO, Eyi YE, Agilli M, Akgul EO, Aydin I, Kaldirim U, Tuncer SK, Eken A, Oztas E, Poyrazoglu Y, Yasar M, Ozkan Y. The protective effects of taurine on experimental acute pancreatitis in a rat model. Hum Exp Toxicol 2013; 32:522-9. [DOI: 10.1177/0960327113482692] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The aim of this study was to investigate the protective effects of taurine (Tau) on experimental acute pancreatitis (AP) in a rat model by measuring cytokines and oxidant stress markers. Forty rats were randomly divided into four groups: sham, AP, Tau and AP + Tau. AP was induced with sodium taurocholate. No treatment was given to the AP. All rats were killed 5 days later. Pancreatic tissues of rats and blood samples were obtained. Tau treatment significantly decreased serum amylase activity ( p < 0.001), total injury score ( p < 0.001), malondialdehyde levels ( p < 0.001) and myeloperoxidase (MPO) activity ( p < 0.001). There was no significant difference between the Tau and AP + Tau groups in serum and pancreatic tumor necrosis factor-α, interleukin (IL)-1β and IL-6 levels ( p = 1.000). Histopathologic scores in the AP + Tau and Tau groups were significantly lower compared with the AP group (both p < 0.001). These results showed that Tau reduces lipid peroxidation, amylase and MPO activities and the concentrations of proinflammatory cytokines secondary to AP and also increases superoxide dismutase and glutathione peroxidase activities in rats with sodium taurocholate-induced AP. It also has a marked ameliorative effect at histopathologic lesions. With these effects, Tau protects the cells from oxidative damage, reduces inflammation and promotes regression of pancreatic damage.
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Affiliation(s)
- C Akay
- Department of Pharmaceutical Toxicology, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - H Yaman
- Clinical Biochemistry, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - M Oztosun
- Turkish Armed Forces, Health Services Command, Etimesgut, Ankara, Turkey
| | - E Cakir
- Clinical Biochemistry, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - AO Yildirim
- Emergency Medicine, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - YE Eyi
- Emergency Medicine, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - M Agilli
- Clinical Biochemistry, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - EO Akgul
- Clinical Biochemistry, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - I Aydin
- Clinical Biochemistry, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - U Kaldirim
- Emergency Medicine, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - SK Tuncer
- Emergency Medicine, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - A Eken
- Department of Pharmaceutical Toxicology, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - E Oztas
- Histology and Embryology, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - Y Poyrazoglu
- Emergency Medicine, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - M Yasar
- Emergency Medicine, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - Y Ozkan
- Pharmaceutical Technology, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
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Thundyil J, Manzanero S, Pavlovski D, Cully TR, Lok KZ, Widiapradja A, Chunduri P, Jo DG, Naruse C, Asano M, Launikonis BS, Sobey CG, Coulthard MG, Arumugam TV. Evidence that the EphA2 receptor exacerbates ischemic brain injury. PLoS One 2013; 8:e53528. [PMID: 23308246 PMCID: PMC3538581 DOI: 10.1371/journal.pone.0053528] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 11/28/2012] [Indexed: 12/17/2022] Open
Abstract
Ephrin (Eph) signaling within the central nervous system is known to modulate axon guidance, synaptic plasticity, and to promote long-term potentiation. We investigated the potential involvement of EphA2 receptors in ischemic stroke-induced brain inflammation in a mouse model of focal stroke. Cerebral ischemia was induced in male C57Bl6/J wild-type (WT) and EphA2-deficient (EphA2−/−) mice by middle cerebral artery occlusion (MCAO; 60 min), followed by reperfusion (24 or 72 h). Brain infarction was measured using triphenyltetrazolium chloride staining. Neurological deficit scores and brain infarct volumes were significantly less in EphA2−/− mice compared with WT controls. This protection by EphA2 deletion was associated with a comparative decrease in brain edema, blood-brain barrier damage, MMP-9 expression and leukocyte infiltration, and higher expression levels of the tight junction protein, zona occludens-1. Moreover, EphA2−/− brains had significantly lower levels of the pro-apoptotic proteins, cleaved caspase-3 and BAX, and higher levels of the anti-apoptotic protein, Bcl-2 as compared to WT group. We confirmed that isolated WT cortical neurons express the EphA2 receptor and its ligands (ephrin-A1–A3). Furthermore, expression of all four proteins was increased in WT primary cortical neurons following 24 h of glucose deprivation, and in the brains of WT mice following stroke. Glucose deprivation induced less cell death in primary neurons from EphA2−/− compared with WT mice. In conclusion, our data provide the first evidence that the EphA2 receptor directly contributes to blood-brain barrier damage and neuronal death following ischemic stroke.
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Affiliation(s)
- John Thundyil
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
| | - Silvia Manzanero
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
| | - Dale Pavlovski
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
| | - Tanya R. Cully
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
| | - Ker-Zhing Lok
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
| | - Alexander Widiapradja
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
| | - Prasad Chunduri
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
| | - Dong-Gyu Jo
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Chie Naruse
- Division of Transgenic Animal Science, Advanced Science Research Center, Kanazawa University, 13-1 Takara-machi, Kanazawa, Japan
| | - Masahide Asano
- Division of Transgenic Animal Science, Advanced Science Research Center, Kanazawa University, 13-1 Takara-machi, Kanazawa, Japan
| | - Bradley S. Launikonis
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
| | - Christopher G. Sobey
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Mark G. Coulthard
- Academic Discipline of Paediatrics and Child Health, University of Queensland, Royal Children’s Hospital, Herston, Queensland, Australia
- Paediatric Intensive Care Unit, Royal Children's Hospital, Herston, Queensland, Australia
- Queensland Children’s Medical Research Institute, Royal Children's Hospital, Herston, Queensland, Australia
| | - Thiruma V. Arumugam
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
- * E-mail:
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Lipopolysaccharide-preconditioning protects against endotoxin-induced white matter injury in the neonatal rat brain. Brain Res 2012; 1489:81-9. [PMID: 23063716 DOI: 10.1016/j.brainres.2012.10.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 09/12/2012] [Accepted: 10/06/2012] [Indexed: 11/22/2022]
Abstract
BACKGROUND Exposing the brain to a sub-damaging stimulus can protect against a subsequent lethal insult, a phenomenon termed preconditioning. The aim of this study was to investigate the neuroprotective effect of low dose LPS (lipopolysaccharide) pretreatment in endotoxin induced periventricular leukomalacia (PVL) in a rat model. METHODS Wistar rats with dated pregnancies were allocated to 5 groups: (i) no LPS administered, intraperitoneally (i.p.) pyrogen-free saline injected (Control group), (ii) 500μg/kg LPS administrated i.p. on days 18 and 19 (PVL group), (iii) 50μg/kg LPS administrated i.p. on day 17 followed by 500μg/kg LPS i.p. on days 18 and 19 (PC-PVL group), (iv) 50μg/kg LPS administrated on day 17 (PC only), and (v) i.p. pyrogen-free saline injected control group on day 17. RESULTS LPS-preconditioning given 24h before potent LPS exposure significantly reduced the number of apoptotic cell deaths and prevented hypomyelination. Antioxidant enzyme gene expression levels (Superoxide Dismutase-SOD1, SOD2, and SOD3) were increased and Tumor Necrosis Factor (TNF)α expression levels were decreased in the PC+PVL group when compared with the PVL group. CONCLUSION Low-dose LPS given one day before potent doses of LPS reduces antepartum LPS-induced brain damage. The mechanisms of protection might involve oxidation and inflammation.
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Grin’kina NM, Karnabi EE, Damania D, Wadgaonkar S, Muslimov IA, Wadgaonkar R. Sphingosine kinase 1 deficiency exacerbates LPS-induced neuroinflammation. PLoS One 2012; 7:e36475. [PMID: 22615770 PMCID: PMC3355156 DOI: 10.1371/journal.pone.0036475] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 04/09/2012] [Indexed: 11/24/2022] Open
Abstract
The pathogenesis of inflammation in the central nervous system (CNS), which contributes to numerous neurodegenerative diseases and results in encephalopathy and neuroinflammation, is poorly understood. Sphingolipid metabolism plays a crucial role in maintaining cellular processes in the CNS, and thus mediates the various pathological consequences of inflammation. For a better understanding of the role of sphingosine kinase activation during neuroinflammation, we developed a bacterial lipopolysaccharide (LPS)-induced brain injury model. The onset of the inflammatory response was observed beginning 4 hours after intracerebral injection of LPS into the lateral ventricles of the brain. A comparison of established neuroinflammatory parameters such as white matter rarefactions, development of cytotoxic edema, astrogliosis, loss of oligodendrocytes, and major cytokines levels in wild type and knockout mice suggested that the neuroinflammatory response in SphK1-/- mice was significantly upregulated. At 6 hours after intracerebroventricular injection of LPS in SphK1-/- mice, the immunoreactivity of the microglia markers and astrocyte marker glial fibrillary acidic protein (GFAP) were significantly increased, while the oligodendrocyte marker O4 was decreased compared to WT mice. Furthermore, western blotting data showed increased levels of GFAP. These results suggest that SphK1 activation is involved in the regulation of LPS induced brain injury. RESEARCH HIGHLIGHTS: • Lipopolysaccharide (LPS) intracerebral injection induces severe neuroinflammation. • Sphingosine kinase 1 deletion worsens the effect of the LPS. • Overexpression of SphK1 might be a potential new treatment approach to neuroinflammation.
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Affiliation(s)
- Natalia M. Grin’kina
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
- Department of Research and Development VA Medical Center, Brooklyn, New York, United States of America
| | - Eddy E. Karnabi
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
- Department of Research and Development VA Medical Center, Brooklyn, New York, United States of America
| | - Dushyant Damania
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
| | - Sunil Wadgaonkar
- Department of Research and Development VA Medical Center, Brooklyn, New York, United States of America
| | - Ilham A. Muslimov
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
| | - Raj Wadgaonkar
- SUNY Downstate Medical Center, Brooklyn, New York, United States of America
- Department of Research and Development VA Medical Center, Brooklyn, New York, United States of America
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Neuroprotective effect of fucoidin on lipopolysaccharide accelerated cerebral ischemic injury through inhibition of cytokine expression and neutrophil infiltration. J Neurol Sci 2012; 318:25-30. [PMID: 22560605 DOI: 10.1016/j.jns.2012.04.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2011] [Revised: 03/25/2012] [Accepted: 04/11/2012] [Indexed: 11/22/2022]
Abstract
In our previous study, we reported that lipopolysaccharide (LPS) activated microglia and accelerated cerebral ischemic injury in the rat brain through the overexpression of cytokines in microglia. In the present study, we investigated the effect of the intraperitoneal administration of fucoidin, a potent inhibitor of leukocyte rolling and anti-inflammatory agent, against accelerated cerebral ischemic injury by LPS pretreatment using rats. We found that fucoidin treatment inhibited the expressions of some brain cytokine or chemokine mRNA such as IL-8, TNF-α and iNOS in the brain of the rats treated only with LPS. We also observed that fucoidin treatment dramatically decreased the infarct size in accelerated cerebral ischemic injury induced by LPS treatment at an early time after ischemic injury. In addition, the immunoreactivity of myleoperoxidase (MPO), a marker for quantifying neutrophil accumulation, was distinctively decreased in the ischemic brain of the fucoidin-treated rat. In brief, our results indicate that fucoidin showed a neuroprotective effect on LPS accelerated cerebral ischemic injury through inhibiting the expression of some cytokine/chemokine and neutrophil recruitments.
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Popovich PG, Tovar CA, Wei P, Fisher L, Jakeman LB, Basso DM. A reassessment of a classic neuroprotective combination therapy for spinal cord injured rats: LPS/pregnenolone/indomethacin. Exp Neurol 2011; 233:677-85. [PMID: 22177997 DOI: 10.1016/j.expneurol.2011.11.045] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 11/17/2011] [Accepted: 11/29/2011] [Indexed: 11/20/2022]
Abstract
These experiments were completed as part of an NIH-NINDS contract entitled "Facilities of Research Excellence-Spinal Cord Injury (FORE-SCI)-Replication". Our goal was to replicate data from a paper published by Dr. Lloyd Guth and colleagues in which combined injections of lipopolysaccharide, indomethacin and pregnenolone (referred to herein as LIP therapy) conferred marked neuroprotection in a pre-clinical model of spinal cord injury (SCI). Specifically, post-injury injection of the combination LIP therapy was found to significantly reduce tissue damage at/nearby the site of injury and significantly improve recovery of locomotor function. In this report, we confirm the primary observations made by Guth et al., however, the effects of LIP treatment were modest. Specifically, LIP treatment improved myelin and axon sparing, axonal sprouting while reducing lesion cavitation. However, spontaneous recovery of locomotion, as assessed using historical (Tarlov scoring) and more current rating scales (i.e., BBB scoring), was not affected by LIP treatment. Instead, more refined parameters of functional recovery (paw placement accuracy during grid walk) revealed a significant effect of treatment. Possible explanations for the neuroprotective effects of LIP therapy are described along with reasons why the magnitude of neuroprotection may have differed between this study and that of Guth and colleagues.
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Affiliation(s)
- Phillip G Popovich
- Center for Brain and Spinal Cord Repair, The Ohio State University College of Medicine, Columbus, OH, USA.
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Longhi L, Gesuete R, Perego C, Ortolano F, Sacchi N, Villa P, Stocchetti N, De Simoni MG. Long-lasting protection in brain trauma by endotoxin preconditioning. J Cereb Blood Flow Metab 2011; 31:1919-29. [PMID: 21468087 PMCID: PMC3185879 DOI: 10.1038/jcbfm.2011.42] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
We investigated the occurrence of endotoxin (lipopolysaccharide, LPS) preconditioning in traumatic brain injury (TBI), evaluating the time window of LPS-induced protection, its persistence, and the associated molecular mechanisms. Mice received 0.1 mg/kg LPS or saline intraperitoneally and subsequently TBI (by controlled cortical impact brain injury) at various time intervals. Mice receiving LPS 3, 5, or 7 days before TBI showed attenuated motor deficits at 1 week after injury compared with mice receiving saline. Those receiving LPS 5 days before injury had also a reduced contusion volume (7.9±1.3 versus 12±2.3 mm(3)) and decreased cell death. One month after injury, the protective effect of LPS on contusion volume (14.5±1.2 versus 18.2±1.2 mm(3)) and neurologic function was still present. Traumatic brain injury increased glial fibrillary acidic protein, CD11b, CD68, tumor necrosis factor-α, interleukin (IL)-10, and IL-6 mRNA expression 24 hours after injury. Lipopolysaccharide administered 5 (but not 9) days before injury increased the expression of CD11b (233%) and of interferon β (500%) in uninjured mice, while it reduced the expression of CD68 (by 46%) and increased that of IL-6 (by 52%) in injured mice. Lipopolysaccharide preconditioning conferred a long-lasting neuroprotection after TBI, which was associated with a modulation of microglia/macrophages activity and cytokine production.
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Affiliation(s)
- Luca Longhi
- Department of Anesthesia and Critical Care Medicine, University of Milano, Neurosurgical Intensive Care Unit, Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Milano, Italy
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Bingham D, John CM, Panter SS, Jarvis GA. Post-injury treatment with lipopolysaccharide or lipooligosaccharide protects rat neuronal and glial cell cultures. Brain Res Bull 2011; 85:403-9. [PMID: 21571046 DOI: 10.1016/j.brainresbull.2011.04.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 04/28/2011] [Accepted: 04/28/2011] [Indexed: 10/18/2022]
Abstract
Traumatic brain injury (TBI) is a major cause of disability in civilians and military personnel worldwide that is caused by the acceleration force of a primary shockwave, blast wind or the force of a direct contact. Following the primary injury, secondary injury is caused by activation of the immune response due to an influx of neuro-inflammatory cells, increased production of inflammatory cytokines, and edema. In ischemia models pre-conditioning with lipopolysaccharide (LPS) has been shown to be neuroprotective, and post-injury conditioning with LPS was found to be protective in a spinal cord and an acute brain injury model. In this study, we utilized an in vitro scratch model of TBI to assess the effect of post-injury treatment with Escherichia coli LPS and Neisseria meningitidis lipooligosaccharide (LOS) on cell death and cytokine induction by assessing the level of lactate dehydrogenase released from cells and rat multiplex cytokine assays. Our results showed that post-injury treatment of C6 glioma cells with either the LPS or the LOS reduced cell death when compared to scratched controls treated with media only. Post-injury treatment of the primary mixed neuronal cultures with LPS reduced cell death and resulted in a significant up-regulation in IL-10 when compared to controls. With LOS post-scratch treatment of the primary cell cultures, we found that IL-1α, IL-1β, IL-6, and TNF-α were significantly upregulated in addition to IL-10 compared to the media-only controls. The results strongly support additional testing of the neuroprotective ability of post-injury treatment with LPS or LOS in models of TBI.
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Affiliation(s)
- Deborah Bingham
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121, USA.
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30
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Intracellular Signaling: Mediators and Protective Responses. Stroke 2011. [DOI: 10.1016/b978-1-4160-5478-8.10010-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Abstract
OBJECTIVES In this study, the effects of adalimumab (ADA), a fully humanized IgG1 monoclonal antibody to tumor necrosis factor α, on experimentally acute pancreatitis (AP) were examined. METHODS Healthy Wistar rats (n = 32) were randomly divided into 4 groups: group 1, AP; group 2, AP + ADA; group 3, control (physiologic saline), and group 4, physiologic saline + ADA (n = 8/group). Acute pancreatitis was induced with a retrograde injection of 3% sodium (Na)-taurocholate into the common biliopancreatic duct. Adalimumab was simultaneously administered at 50 mg/kg intraperitoneally for groups 2 and 4. Physiologic saline was administered instead of Na-taurocholate for non-AP groups. After 24 hours, serum amylase, lactate dehydrogenase, pancreatic myeloperoxidase, and malondialdehyde activities, along with pancreatic histopathology, were examined. RESULTS Adalimumab treatment significantly decreased serum amylase activity (AP, 2778.25 ± 298.80; AP + ADA, 2143.13 ± 221.69; control, 1541.00 ± 148.39; ADA, 1143.00 ± 256.30 U/L; P < 0.001), lactate dehydrogenase activity (AP, 2978.37 ± 364.65; AP + ADA, 2582.75 ± 164.23; control 931.25 ± 135.93; ADA, 582.62 ± 99.37 U/L; P < 0.001), myeloperoxidase activity (AP, 1.44 ± 0.20; AP + ADA, 0.86 ± 0.01; control, 0.60 ± 0.17; ADA, 0.41 ± 0.00 U/g of wet tissue; P < 0.001), malondialdehyde activity (AP, 16.94 ± 3.98; AP + ADA, 7.66 ± 2.27; control, 9.07 ± 1.00; ADA, 3.58 ± 0.30 nmol/g; P < 0.01), and total histopathologic scores (AP, 2.75 ± 0.16; AP + ADA, 1.50 ± 0.19; control, 0.00 ± 0.00; ADA, 0.00 ± 0.00; P < 0.001). CONCLUSIONS These results support the idea that adalimumab might be beneficial for severity of AP.
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Draisma A, de Goeij M, Wouters CW, Riksen NP, Oyen WJG, Rongen GA, Boerman OC, van Deuren M, van der Hoeven JG, Pickkers P. Endotoxin tolerance does not limit mild ischemia-reperfusion injury in humans in vivo. Innate Immun 2010; 15:360-7. [PMID: 19710089 DOI: 10.1177/1753425909105548] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Animal studies have shown that previous exposure to lipopolysaccharide (LPS) can limit ischemia-reperfusion injury. We tested whether pretreatment with LPS also protects against ischemia-reperfusion injury in humans in vivo. Fourteen volunteers received bolus injections of incremental dosages of LPS on 5 consecutive days (LPS group). Before the first and 1 day after the last LPS administration, the forearm circulation of the non-dominant arm was occluded for 10 min, with concomitant intermittent handgripping to induce transient ischemia. After reperfusion, 0.1 mg of ( 99m)Tc-labeled annexin A5 (400 MBq) was injected intravenously to detect phosphatidylserine expression as an early marker of ischemia-reperfusion injury. Similarly, the control group (n = 10) underwent the ischemic exercise twice, but without pretreatment with LPS. Annexin A5 targeting was expressed as the percentage difference in radioactivity in the thenar muscle between both hands. Endotoxin tolerance developed during 5 consecutive days of LPS administration. Annexin A5 targeting was 12.1 +/- 2.2% and 10.4 +/- 2.1% before LPS treatment at 1 h and 4 h after reperfusion, compared to 12.2 +/- 2.4% and 8.9 +/- 2.1% at 1 h and 4 h after reperfusion on day 5 (P = 1.0 and 0.6, respectively). Also, no significant changes in annexin A5 targeting were found in the control group. So, in this model, LPS-tolerance does not protect against ischemia-reperfusion injury in humans in vivo.
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Affiliation(s)
- Annelies Draisma
- Department of Intensive Care Medicine, Radboud University Nijmegen Medical Centre, The Netherlands
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Abe T, Shimamura M, Jackman K, Kurinami H, Anrather J, Zhou P, Iadecola C. Key role of CD36 in Toll-like receptor 2 signaling in cerebral ischemia. Stroke 2010; 41:898-904. [PMID: 20360550 DOI: 10.1161/strokeaha.109.572552] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND PURPOSE Toll-like receptors (TLRs) and the scavenger receptor CD36 are key molecular sensors for the innate immune response to invading pathogens. However, these receptors may also recognize endogenous "danger signals" generated during brain injury, such as cerebral ischemia, and trigger a maladaptive inflammatory reaction. Indeed, CD36 and TLR2 and 4 are involved in the inflammation and related tissue damage caused by brain ischemia. Because CD36 may act as a coreceptor for TLR2 heterodimers (TLR2/1 or TLR2/6), we tested whether such interaction plays a role in ischemic brain injury. METHODS The TLR activators FSL-1 (TLR2/6), Pam3 (TLR2/1), or lipopolysaccharide (TLR4) were injected intracerebroventricularly into wild-type or CD36-null mice, and inflammatory gene expression was assessed in the brain. The effect of TLR activators on the infarct produced by transient middle cerebral artery occlusion was also studied. RESULTS The inflammatory response induced by TLR2/1 activation, but not TLR2/6 or TLR4 activation, was suppressed in CD36-null mice. Similarly, TLR2/1 activation failed to increase infarct volume in CD36-null mice, whereas TLR2/6 or TLR4 activation exacerbated postischemic inflammation and increased infarct volume. In contrast, the systemic inflammatory response evoked by TLR2/6 activation, but not by TLR2/1 activation, was suppressed in CD36-null mice. CONCLUSIONS In the brain, TLR2/1 signaling requires CD36. The cooperative signaling of TLR2/1 and CD36 is a critical factor in the inflammatory response and tissue damage evoked by cerebral ischemia. Thus, suppression of CD36-TLR2/1 signaling could be a valuable approach to minimize postischemic inflammation and the attendant brain injury.
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Affiliation(s)
- Takato Abe
- Division of Neurobiology, Weill Cornell Medical College, 407 E 61st St, Room RR303, New York, NY 10065, USA
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Samanta J, Alden T, Gobeske K, Kan L, Kessler JA. Noggin protects against ischemic brain injury in rodents. Stroke 2009; 41:357-62. [PMID: 20019326 DOI: 10.1161/strokeaha.109.565523] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Bone morphogenetic proteins and their receptors are expressed in adult brains, and their expression levels increase after cerebral ischemia. The brain also expresses an inhibitor of bone morphogenetic protein signaling, noggin, but the role of noggin in ischemic disease outcome has not been studied. METHODS We used transgenic mice overexpressing noggin to assess whether inhibition of bone morphogenetic protein signaling affects ischemic injury responses after permanent middle cerebral artery occlusion. RESULTS Transgenic mice overexpressing noggin mice had significantly smaller infarct volumes and lower motor deficits compared to wild-type mice. CD11b(+) and IBA1(+) microglia along with oligodendroglial progenitors were significantly increased in transgenic mice overexpressing noggin mice at 14 days after permanent middle cerebral artery occlusion. CONCLUSIONS These results provide genetic evidence that overexpression of noggin reduces ischemic brain injury after permanent middle cerebral artery occlusion via enhanced activation of microglia and oligodendrogenesis.
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Affiliation(s)
- Jayshree Samanta
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Ill, USA
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36
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Yilmaz M, Topsakal S, Herek O, Ozmen O, Sahinduran S, Buyukoglu T, Yonetci N. Effects of etanercept on sodium taurocholate-induced acute pancreatitis in rats. Transl Res 2009; 154:241-9. [PMID: 19840765 DOI: 10.1016/j.trsl.2009.07.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 07/13/2009] [Accepted: 07/15/2009] [Indexed: 12/22/2022]
Abstract
In this study, we examined the effects of etanercept (ETA) on experimentally induced pancreatitis. Acute pancreatitis was induced with Na taurocholate. ETA was simultaneously administered to treatment groups. Serum amylase and lipase activity, pancreatic histopathology, apoptosis, malondialdehyde (MDA), and myeloperoxidase enzyme activity (MPO) were assessed. Although rats in the groups 1, 2, and 3 were sacrificed 24h later, groups 4, 5, and 6 were sacrificed 5 days later. ETA treatment significantly decreased serum amylase activity (nontreated, 2636.16+/-191.94; treated, 1898.71+/-262.53; control, 506.28+/-17.31 U/L, P<0.001), lipase activity (nontreated, 3049.67+/-972.65; treated, 2538.85+/-660.45; control, 88.57+/-7.54 U/L, P<0.001), histopathologic score (nontreated, 5.43+/-0.43; treated, 2.57+/-0.20; control, 0.71+/-0.18, P<0.001), MDA (nontreated, 105.77+/-13.29; treated, 92.89+/-10.39; control, 41.26+/-2.54 nmol/g, P<0.001), and MPO (nontreated, 0.64+/-1.15; treated, 0.59+/-0.13; control, 0.17+/-0.02 units/g/wet weight, P<0.001) activity in 24-h groups. In 5-day groups, ETA treatment decreased amylase activity (nontreated, 738.67+/-48.60; treated, 497.14+/-47.25; control, 389.00+/-9.17 U/L, P<0.001), lipase activity (nontreated, 101.33+/-39.32; treated, 34.57+/-7.29; control, 23.42+/-2.12 U/L, P<0.001), histopathologic score (nontreated, 5.43+/-0.43; treated, 3.71+/-0.68; control, 0.00+/-0.00, P<0.001), MDA (nontreated, 67.91+/-4.28; treated, 60.91+/-3.57; control, 14.85+/-1.16 nmol/g, P<0.001), and MPO (nontreated, 0.36+/-0.04; treated, 0.27+/-0.02; control, 0.14+/-0.02 units/g/wet weight, P<0.001) activity. Caspase-positive cells numbers around the necrosis significantly decreased by ETA treatment in both 24-h groups (nontreated, 74.28+/-3.26; treated, 67.00+/-1.15; control, 3.85+/-0.63, P<0.001) and 5-day groups (nontreated, 79.85+/-3.01; treated, 47.85+/-5.76; control, 2.22+/-0.63, P<0.001). These results showed that ETA has an ameliorating effect on sodium taurocholate-induced acute necrotic pancreatitis.
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Affiliation(s)
- Mustafa Yilmaz
- Department of Internal Medicine, University of Pamukkale, Denizli, Turkey
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Lin HY, Huang CC, Chang KF. Lipopolysaccharide preconditioning reduces neuroinflammation against hypoxic ischemia and provides long-term outcome of neuroprotection in neonatal rat. Pediatr Res 2009; 66:254-9. [PMID: 19531979 DOI: 10.1203/pdr.0b013e3181b0d336] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Hypoxic ischemia (HI) in newborns causes long-term neurologic abnormalities. Systemic lipopolysaccharide (LPS) is neuroprotective in neonatal rats when injected 24 h before HI. However, the effect on HI-induced neuroinflammation and the long-term outcome of LPS preconditioning in neonatal rats have not been examined. In a rat-pup HI model, compared with normal saline (NS), 0.3 mg/kg of LPS injected 24 h before HI greatly increased microglial cell and macrophage activation and up-regulated TNF-alpha and inducible NOS expression 12-h postinjection and resulted in high mortality during HI. In contrast, 0.05 mg/kg of LPS elicited very little microglia and macrophage activation and TNF-alpha and inducible NOS expression and resulted in low mortality. Given 24 h before HI, low-dose (0.05 mg/kg) LPS greatly reduced microglia and macrophage activation, TNF-alpha expression, and reactive oxygen species production 24-h post-HI compared with NS-treated rats. Rats in the low-dose LPS group also showed significantly better learning and memory and less brain damage in adulthood. Learning and memory performance among the LPS-HI, LPS, and NS groups was not significantly different. We conclude that low-dose LPS preconditioning in neonatal rats greatly reduces HI-induced neuroinflammation and provides long-term neuroprotection against behavioral and pathologic abnormalities.
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Affiliation(s)
- Hsiang-Yin Lin
- Institute of Basic Medical Sciences, National Cheng Kung University College of Medicine, Tainan City 70428, Taiwan
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38
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Joice SL, Mydeen F, Couraud PO, Weksler BB, Romero IA, Fraser PA, Easton AS. Modulation of blood-brain barrier permeability by neutrophils: in vitro and in vivo studies. Brain Res 2009; 1298:13-23. [PMID: 19728990 DOI: 10.1016/j.brainres.2009.08.076] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Revised: 08/06/2009] [Accepted: 08/21/2009] [Indexed: 11/28/2022]
Abstract
The blood-brain barrier (BBB) restricts solute permeability across healthy cerebral endothelial cells. However, during inflammation, permeability is increased and can lead to deleterious cerebral edema. Neutrophils are early cellular participants in acute inflammation, but their effect on BBB permeability is unclear. To study this, neutrophils were applied in a resting and activated state to in vitro and in vivo models of the BBB. In vitro, human neutrophils (5 x 10(6)/ml) were activated with tumor necrosis factor (100 U/ml) and leukotriene B(4) (10(-7) mol/l). Untreated neutrophils reduced permeability across the human brain endothelial cell line hCMEC/D3. Activated neutrophils returned permeability to baseline, an effect blocked by the reactive oxygen scavengers superoxide dismutase (10 U/ml) and catalase (1000 U/ml). In vivo, human neutrophils (2.5 x1 0(5) in 4 microl) were injected into the striatum of anesthetized juvenile Wistar rats, and BBB permeability measured 30 min later. This was compared to control injections (4 microl) of vehicle (0.9% saline) and arachidonic acid (10(-3) mol/l). The injection generated a small hematoma around the injection tract (<3 microl). Untreated neutrophils induced significantly lower permeability in their vicinity than activated neutrophils, with a trend to lowered permeability compared to the vehicle control. Neither untreated nor activated neutrophils induced permeability increases, while arachidonic acid increased permeability as a positive control. This study further delineates the effect of neutrophils on the BBB, and demonstrates that resting neutrophils induce acute reductions in permeability while activated neutrophils have a neutral effect. The in vivo model reiterates some aspects of acute intracerebral hemorrhage.
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Affiliation(s)
- Shannon L Joice
- Department of Pathology, Dalhousie University, 5850 College Street, Halifax, Nova Scotia, Canada
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Behavioural and histological effects of preconditioning with lipopolysaccharide in epileptic rats. Neurochem Res 2009; 35:262-72. [PMID: 19728087 DOI: 10.1007/s11064-009-0050-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Accepted: 08/13/2009] [Indexed: 10/20/2022]
Abstract
Sublethal stress stimuli such as systemic endotoxin treatment can induce tolerance of the brain to subsequent ischemic stress, which results in a decreased infarct size. Based on this evidence, we hypothesized that lipopolysaccharide (LPS)-induced preconditioning could protect hippocampal neurons in epileptic rats. To test this hypothesis, the anticonvulsant effect of a low dose of LPS against seizures elicited by pilocarpine hydrochloride was measured. Using the pilocarpine model of temporal lobe epilepsy and LPS-preconditioning, we also investigated hippocampal pathology in the rat brain. Based on the behavioural observations conducted, it can be assumed that the preconditioning procedure used may decrease seizure excitability in epileptic rats. However, determination of the seizure excitability threshold needs to be elaborated. Qualitative and quantitative analyses of histological brain sections in the LPS-preconditioned rats showed markedly decreased intensity of neurodegenerative changes in the CA1, CA3 and DG hippocampal fields. The tendency was observed in all the periods of the pilocarpine model of epilepsy. We suggest that preconditioning with LPS may have neuroprotective effects in the CA1, CA3 and DG hippocampal sectors; however, it has no influence on the course of the seizures in rats in the pilocarpine model of epilepsy.
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Draisma A, Pickkers P, Bouw MP, van der Hoeven JG. Development of endotoxin tolerance in humans in vivo. Crit Care Med 2009; 37:1261-7. [DOI: 10.1097/ccm.0b013e31819c3c67] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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41
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Meller R. The role of the ubiquitin proteasome system in ischemia and ischemic tolerance. Neuroscientist 2009; 15:243-60. [PMID: 19181875 DOI: 10.1177/1073858408327809] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Ubiquitin modification targets a protein for rapid degradation by the proteasome. However, polyubiquitination of proteins can result in multiple functions depending on the topology of the ubiquitin chain. Therefore, ubiquitin signaling offers a more complex and versatile biology compared with many other posttranslational modifications. One area of potential for the application of this knowledge is the field of ischemia-induced brain damage, as occurs following a stroke. The ubiquitin proteasome system may exert a dual role on neuronal outcome following ischemia. Harmful ischemia results in an overload of the ubiquitin proteasome system, and blocking the proteasome reduces brain infarction following ischemia. However, the rapid and selective degradation of proteins following brief ischemia results in endogenous protection against ischemia. Therefore, further understanding of the molecular signaling mechanisms that regulate the ubiquitin proteasome system may reveal novel therapeutic targets to reduce brain damage when ischemia is predicted or reduce the activation of the cell death mechanisms and the inflammatory response following stroke. The aim of this review is to discuss some of the recent advances in the understanding of protein ubiquitination and its implications for novel stroke therapies.
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Affiliation(s)
- Robert Meller
- Legacy Clinical Research and Technology Center, Portland, Oregon, USA.
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42
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Ding Y, Li L. Lipopolysaccharide preconditioning induces protection against lipopolysaccharide-induced neurotoxicity in organotypic midbrain slice culture. Neurosci Bull 2008; 24:209-18. [PMID: 18668149 DOI: 10.1007/s12264-008-0408-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
OBJECTIVE To identify the protective effect of lipopolysaccharide (LPS) preconditioning against LPS-induced inflammatory damage in dopaminergic neurons of midbrain slice culture and the possible mechanisms. METHODS After cultured in vitro for 14 d, the rat organotypic midbrain slices were pretreated with different concentrations (0, 1, 3, 6 or 10 ng/mL) of LPS for 24 h followed by treatment with 100 ng/mL LPS for 72 h. The whole slice viability was determined by measurement of the activity of lactic acid dehydrogenase (LDH). Tyrosine hydroxylase-immunoreactive (TH-IR) neurons and CD11b/c equivalent-immunoreactive (OX-42-IR) microglia in the slices were observed by immunohistochemical method, and tumor necrosis factor-alpha (TNF-alpha) levels in the culture media were detected by enzyme-linked immunosorbent assays (ELISA). RESULTS In the slices treated with 100 ng/mL LPS for 72 h, the number of TH-IR neurons reduced from 191+/-12 in the control slices to 46+/-4, and the LDH activity elevated obviously (P < 0.01), along with remarkably increased number of OX-42-IR cells and production of TNF-alpha (P < 0.01). Preconditioning with 3 or 6 ng/mL LPS attenuated neuron loss (the number of TH-IR neurons increased to 126+/-12 and 180+/-13, respectively) and markedly reduced LDH levels (P < 0.05), accompanied by significant decreases of OX-42-IR microglia activation and TNF-alpha production (P < 0.05). CONCLUSION Low-dose LPS preconditioning could protect dopaminergic neurons against inflammatory damage in rat midbrain slice culture, and inhibition of microglial activation and reduction of the proinflammatory factor TNF-alpha production may contribute to this protective effect. Further understanding the underlying mechanism of LPS preconditioning may open a new window for treatment of Parkinson's disease.
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Affiliation(s)
- Ye Ding
- Department of Pathology, Capital Medical University, Beijing, China
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Marsh BJ, Williams-Karnesky RL, Stenzel-Poore MP. Toll-like receptor signaling in endogenous neuroprotection and stroke. Neuroscience 2008; 158:1007-20. [PMID: 18809468 DOI: 10.1016/j.neuroscience.2008.07.067] [Citation(s) in RCA: 206] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Revised: 07/29/2008] [Accepted: 07/30/2008] [Indexed: 12/31/2022]
Abstract
Stroke and other cerebral vascular diseases are a leading cause of morbidity and mortality in the United States. Despite intensive research to identify interventions that lessen cerebrovascular injury, no major therapies exist. Development of stroke prophylaxis involves an understanding of the mechanisms of damage following cerebral ischemia, and elucidation of the endogenous mechanisms that combat further brain injury. Toll-like receptors (TLRs) are critical components of the innate immune system that have been shown recently to mediate ischemic injury. Paradoxically, TLR ligands administered systemically induce a state of tolerance to subsequent ischemic injury. Herein we suggest that stimulation of TLRs prior to ischemia reprograms TLR signaling that occurs following ischemic injury. Such reprogramming leads to suppressed expression of pro-inflammatory molecules and enhanced expression of numerous anti-inflammatory mediators that collectively confer robust neuroprotection. Our findings indicate that numerous preconditioning stimuli lead to TLR activation, an event that occurs prior to ischemia and ultimately leads to TLR reprogramming. Thus genomic reprogramming of TLR signaling may be a unifying principle of tolerance to cerebral ischemia.
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Affiliation(s)
- B J Marsh
- Department of Molecular Microbiology and Immunology L220, Oregon Health and Science University, 3181 Southwest Sam Jackson Park Road, Portland, OR 97239, USA.
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Huang CY, Yang HI, Chen SD, Shaw FZ, Yang DI. Protective effects of lipopolysaccharide preconditioning against nitric oxide neurotoxicity. J Neurosci Res 2008; 86:1277-89. [PMID: 18092358 DOI: 10.1002/jnr.21594] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have characterized lipopolysaccharide (LPS) preconditioning-induced neuroprotective mechanisms against nitric oxide (NO) toxicity. Pretreatment of rat cortical cultures with LPS attenuated neurotoxicity of NO donors, including sodium nitroprusside (SNP) and diethylamine NONOate (NONOate). A transiently increased expression of endothelial nitric oxide synthase (eNOS) accompanied by an increase in NO production was observed during LPS preconditioning. Application of NOS inhibitors including L-N(5)-(1-iminoethyl)-ornithine (L-NIO) and L-nitroarginine methylester (L-NAME) abolished LPS-dependent protection against SNP toxicity. The LPS effect was also blocked by KT5823, an inhibitor of cGMP-dependent protein kinase (PKG). Consistently, application of 8-bromo-cyclic GMP (8-Br-cGMP), a slowly degradable cGMP analogue capable of PKG activation, was neuroprotective. LPS preconditioning resulted in a heightened neuronal expression of Bcl-2 protein that was abolished by L-NAME and KT5823, the respective inhibitors of NOS and PKG. Together, our results reveal the signaling cascade of "LPS --> eNOS --> NO --> cGMP/PKG --> Bcl-2" that might have contributed to the LPS protective effects in cortical neurons.
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Affiliation(s)
- Chia-Yen Huang
- Institute of Neuroscience, Tzu Chi University, Hualien, Taiwan
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Wang X, Carmichael DW, Cady EB, Gearing O, Bainbridge A, Ordidge RJ, Raivich G, Peebles DM. Greater hypoxia-induced cell death in prenatal brain after bacterial-endotoxin pretreatment is not because of enhanced cerebral energy depletion: a chicken embryo model of the intrapartum response to hypoxia and infection. J Cereb Blood Flow Metab 2008; 28:948-60. [PMID: 18030303 DOI: 10.1038/sj.jcbfm.9600586] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Infection is a risk factor for adult stroke and neonatal encephalopathy. We investigated whether exposure to bacterial endotoxin increases hypoxia-induced brain cell death and impairs cerebral metabolic compensatory responses to hypoxia. Prehatching chicken embryos (incubation day 19) were exposed to bacterial lipopolysaccharide (LPS) (3 mg Salmonella typhimurium LPS per egg) or hypoxia (4% ambient O(2) for 1 h), alone or in combination with LPS, followed 4 h later by hypoxia. Cerebral cell death and glial activation were assessed histologically. Further, chicken embryo brains were studied by magnetic resonance imaging (MRI) and spectroscopy (MRS) to assess haemodynamic and metabolic responses. In most brain areas, combined LPS/hypoxia resulted in a 30- to 100-fold increase in terminal deoxynucleotidyl transferase dUTP nick end labelling -positive cells, compared to control and single-insult groups. Glial activation correlated with the severity of cell death and was significantly greater in the combined-insult group (P<0.05). Hypoxia was associated with a 10-fold increase in lactate/N-acetyl-aspartate (NAA), an approximately 20% increase in total creatine/NAA, rapid decreases in T2 and T2(*), and a reduction in direction-averaged brain-water diffusion (D(av)) by approximately 15%. Liposaccharide pretreatment did not alter the magnitude or timing of these responses, but engendered baseline shifts (increased Cho/NAA, Cr/NAA, and Dav, and reduced T2(*)). In conclusion, LPS greatly increased hypoxia-induced brain damage in this model and induced changes in baseline haemodynamics and metabolism but did not affect the magnitude of the glycolytic response to hypoxia. The damage-enhancing effects of LPS are not because of additional energy depletion but because of a synergistic toxic component.
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Affiliation(s)
- Xiaolan Wang
- Centre for Perinatal Brain Research, The Institute for Women's Health, University College London, London, UK
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Impact of indolent inflammation on neonatal hypoxic-ischemic brain injury in mice. Int J Dev Neurosci 2007; 26:57-65. [PMID: 17923368 DOI: 10.1016/j.ijdevneu.2007.08.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Revised: 08/13/2007] [Accepted: 08/16/2007] [Indexed: 02/02/2023] Open
Abstract
This report describes a new experimental model to evaluate the effect of a recurrent systemic inflammatory challenge, after cerebral hypoxia-ischemia in immature mice, on the progression of brain injury. Treatment with a low dose of lipopolysaccharide (E. coli O55:B5, 0.2mg/kg for 3 days, then 0.1mg/kg for 2 days) daily for 5 days after unilateral cerebral hypoxia-ischemia (right carotid ligation followed by 35min in 10% O2) in 10-day-old mice resulted in increased right forebrain tissue damage (35.6% reduction in right hemisphere volume compared to 20.6% reduction in saline-injected controls), in bilateral reductions in corpus callosum area (by 12%) and myelin basic protein immunostaining (by 19%), and in suppression of injury-related right subventricular zone cellular proliferation. The post-hypoxic-ischemic lipopolysaccharide regimen that amplified brain injury was not associated with increased mortality, nor with changes in body temperature, weight gain or blood glucose concentrations. The results of the present study demonstrate that systemic inflammation influences the evolution of tissue injury after neonatal cerebral hypoxia-ischemia and may also impair potential recovery mechanisms.
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Abstract
Infections are important risk factors of perinatal brain injury. However, under certain circumstances, inflammation mediates preconditioning and provides protection to the immature brain. Recent experimental studies have examined the interaction of lipopolysaccharide (LPS) with other events. Evidence demonstrates that LPS administered 24h before hypoxia-ischemia in 7-day-old rats provides neuroprotection, which is associated with up-regulation of endogenous corticosterone but is also linked to significant cerebral gene regulation. Gene ontology analysis reveals that the most over-represented genes belong to immune and inflammatory processes. However, a number of cell death/survival genes, including complement component 1, complement component 3, aquaporin 4, epidermal growth factor receptor pathway substrate 15 and PYD and CARD domain containing are also significantly up-regulated 24h following LPS exposure. These results suggest that in addition to immune-related activation, transcription of cell death pathways may be important in LPS-induced preconditioning in the immature brain.
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Affiliation(s)
- Carina Mallard
- Perinatal Center, Department of Neuroscience and Physiology, Sahlgrenska Academy, Göteborg University, Box 432, Göteborg, Sweden.
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Lyng K, Munkeby BH, Scheie D, Mallard C, Hagberg H, Stray-Pedersen B, Saugstad OD, Frøen JF. Fetal brain injury in experimental intrauterine asphyxia and inflammation in Göttingen minipigs. J Perinat Med 2006; 34:226-34. [PMID: 16602844 DOI: 10.1515/jpm.2006.041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To examine fetal brain injury in the Göttingen minipig following intrauterine asphyxia and infection/inflammation induced at 3/4 of gestational length. METHODS We performed laparotomy after anesthesia in six pregnant sows. We randomized 29 fetuses to one of four groups: pretreatment with saline or endotoxin followed by 30 min of umbilical cord occlusion or no occlusion. After 48 h we performed a re-laparotomy and examined the fetal brains. RESULTS After total asphyxia, brain stem injury was present in the group pretreated with saline (P < 0.01 vs. controls) and with endotoxin (P < 0.005 vs. controls). Microglia activation was more marked in the brain stem (P < 0.05) and posterior white matter (P < 0.05) in the asphyxia group than in controls. Two of five fetuses in the asphyxia group had white matter injury, while no white matter lesions were found in the asphyxia/inflammation or endotoxin only groups. CONCLUSIONS In this Göttingen minipig model, a species closer to humans than animals commonly used in experimental studies of perinatal brain injuries, intrauterine asphyxia following pretreatment with saline caused brain stem and white matter injury. This model can be further developed to study the impact of other intrauterine exposures on brain injury.
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Affiliation(s)
- Kristin Lyng
- Department of Obstetrics and Gynecology, Rikshospitalet University Hospital, Oslo, Norway.
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Kulahava TA, Semenkova GN, Kvacheva ZB, Cherenkevich SN, Timoshenko AV. Effects of peroxynitrite and lipopolysaccharide on mitotic activity of C6 glioma cells. Neurosci Lett 2006; 398:286-90. [PMID: 16480818 DOI: 10.1016/j.neulet.2006.01.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2005] [Revised: 12/28/2005] [Accepted: 01/05/2006] [Indexed: 11/23/2022]
Abstract
Peroxynitrite is one of the most potent neurotoxic agents with multiple targets in neurons and glial cells. This study addressed a question of whether peroxynitrite-mediated cytotoxicity can be prevented by Escherichia coli lypopolisaccharide (LPS) due to its mitogenic activity towards C6 glioma cells. A number of characteristic morphological changes (processes impairments, nuclei modifications, cytoplasm vacuolization) and apoptotic cells were observed in the cell culture after 24-h treatment with 3-morpholinosyndnonimine (SIN-1), a well-known donor of peroxynitrite. These morphological changes were clearly associated with a SIN-1 dose-dependent increase in the number of pathological mitoses as well as with SIN-1 inhibition of the menadione-induced, lucigenin-enhanced chemiluminescence of C6 glioma cells, an independent indicator of mitotic activity of these cells. The mitotic index of C6 glioma cells increased in response to LPS and underwent non-uniform changes depending on SIN-1 concentrations. At a mitogenic concentration of 100 ng/ml, LPS reduced significantly the toxicity of SIN-1 determined as the accumulation of pathological mitoses, thus acting as a protective agent. Taken together, our findings indicate that SIN-1 specifically impairs the mitotic process in C6 glioma cells, and provide the first evidence that antimitotic effects of peroxynitrite can be restored by LPS.
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Affiliation(s)
- Tatsiana A Kulahava
- Department of Biophysics, Physical Faculty, Belarusian State University, Skaryny ave.4, 220050 Minsk, Belarus.
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Rastogi L, Godbole MM, Ray M, Rathore P, Rathore P, Pradhan S, Gupta SK, Pandey CM. Reduction in oxidative stress and cell death explains hypothyroidism induced neuroprotection subsequent to ischemia/reperfusion insult. Exp Neurol 2006; 200:290-300. [PMID: 16616921 DOI: 10.1016/j.expneurol.2006.02.013] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2005] [Revised: 02/04/2006] [Accepted: 02/10/2006] [Indexed: 10/24/2022]
Abstract
Hypometabolic state following hypothermia is known to protect tissues from ischemic injury. Hypothyroidism produces a hypometabolic state. The present study was undertaken to investigate the protective effects of hypothyroidism following cerebral ischemia and to ascertain the underlying mechanism. Euthyroid (E) and hypothyroid (H) animals were exposed to a 2 h of middle cerebral artery occlusion followed by 24 h of reperfusion (I/R). Specific enzymatic methods and flowcytometry were used to assess the quantitative changes of molecules involved in neuronal damage as well as in protection. As compared to euthyroid ischemic reperfused (E + I/R) rats, H + I/R rats had insignificant neurological deficit, and smaller area of infarct. H + I/R rats had significantly lower markers of oxidative stress, and lactate dehydrogenase (LDH) activity (a marker for necrosis). Natural antioxidant activity (particularly superoxide dismutase) and integrity of mitochondria (membrane potential) were maintained in H + I/R group but not in E + I/R group. The number of neurons undergoing apoptosis significantly lower in hypothyroid ischemic rats as compared to euthyroid ones. These results suggest that hypothyroid animals face ischemia and reperfusion much better compared to euthyroid animals. A possible explanation could be the decreased oxidative stress and maintained antioxidant activity that finally leads to a decrease in necrosis and apoptosis. These observations may suggest strategies to induce brain-specific downregulation of metabolism that may have implications in the management of strokes in human beings.
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Affiliation(s)
- Leena Rastogi
- Department of Endocrinology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Raebareli Road, Lucknow-226014, India
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