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Jickling GC, Liu D, Ander BP, Stamova B, Zhan X, Sharp FR. Targeting neutrophils in ischemic stroke: translational insights from experimental studies. J Cereb Blood Flow Metab 2015; 35:888-901. [PMID: 25806703 PMCID: PMC4640255 DOI: 10.1038/jcbfm.2015.45] [Citation(s) in RCA: 388] [Impact Index Per Article: 43.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 01/23/2015] [Accepted: 01/26/2015] [Indexed: 01/08/2023]
Abstract
Neutrophils have key roles in ischemic brain injury, thrombosis, and atherosclerosis. As such, neutrophils are of great interest as targets to treat and prevent ischemic stroke. After stroke, neutrophils respond rapidly promoting blood-brain barrier disruption, cerebral edema, and brain injury. A surge of neutrophil-derived reactive oxygen species, proteases, and cytokines are released as neutrophils interact with cerebral endothelium. Neutrophils also are linked to the major processes that cause ischemic stroke, thrombosis, and atherosclerosis. Thrombosis is promoted through interactions with platelets, clotting factors, and release of prothrombotic molecules. In atherosclerosis, neutrophils promote plaque formation and rupture by generating oxidized-low density lipoprotein, enhancing monocyte infiltration, and degrading the fibrous cap. In experimental studies targeting neutrophils can improve stroke. However, early human studies have been met with challenges, and suggest that selective targeting of neutrophils may be required. Several properties of neutrophil are beneficial and thus may important to preserve in patients with stroke including antimicrobial, antiinflammatory, and neuroprotective functions.
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Affiliation(s)
- Glen C Jickling
- Department of Neurology, University of California at Davis, Sacramento, California, USA
| | - DaZhi Liu
- Department of Neurology, University of California at Davis, Sacramento, California, USA
| | - Bradley P Ander
- Department of Neurology, University of California at Davis, Sacramento, California, USA
| | - Boryana Stamova
- Department of Neurology, University of California at Davis, Sacramento, California, USA
| | - Xinhua Zhan
- Department of Neurology, University of California at Davis, Sacramento, California, USA
| | - Frank R Sharp
- Department of Neurology, University of California at Davis, Sacramento, California, USA
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Zhu A, Zou T, Xiong G, Zhang J. Association of uric acid with traditional inflammatory factors in stroke. Int J Neurosci 2015; 126:335-41. [PMID: 26001205 DOI: 10.3109/00207454.2015.1015723] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Uric acid (UA) plays an important role in the oxidant stress that causes inflammation. We assessed the association between UA and neutrophil ratio, white blood cell (WBC) count and blood lipid in 524 patients admitted with stroke. Stroke patients with a neutrophil ratio >70% displayed significantly lower UA levels than those with a neutrophil ratio ≤70% (p < 0.05). According to UA quartiles, neutrophil ratio, WBC count, and high-density lipoprotein cholesterol in the UA grade 1 group (≤214.10 μmol/L) were significantly increased over those in other UA grade groups. The results of stepwise regression analysis found that UA levels were inversely associated with neutrophil ratios (B ± SE = -1.11 ± 0.35), high-density lipoprotein cholesterol (B ± SE = -46.18 ± 14.17), total cholesterol (B ± SE = 9.82 ± 3.66), blood urea nitrogen (B ± SE = 6.30 ± 1.73), and creatinine (B ± SE = 0.63 ± 0.10). There is a correlationship between lower serum uric acid with neutrophil ratios in inflammation associated with stroke and the reasons need to be investigated further.
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Affiliation(s)
- Aiqun Zhu
- a Nursing School of Central South University; The Second Xiangya Hospital of Central South University ; Changsha , Hunan 410013 , China
| | - Ting Zou
- b Department of Neurology, The Second Xiangya Hospital , Central South University , Changsha , Hunan 410011 , China
| | - Guangzhong Xiong
- c Department of Emergency, The Second Xiangya Hospital , Central South University , Changsha , Hunan 410011 , China
| | - Jingping Zhang
- d Nursing School of Central South University , Changsha , Hunan 410013 , China
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Abstract
Microglia are considered the brain's resident immune cell involved in immune defense, immunocompetence, and phagocytosis. They maintain tissue homeostasis within the brain and spinal cord under normal condition and serves as its initial host defense system. However, when the central nervous system (CNS) faces injury, microglia respond through signaling molecules expressed or released by neighboring cells. Microglial responses are dual in nature. They induce a nonspecific immune response that may exacerbate CNS injury, especially in the acute stages, but are also essential to CNS recovery and repair. The full range of microglial mechanisms have yet to be clarified, but there is accumulating knowledge about microglial activation in acute CNS injury. Microglial responses require hours to days to fully develop, and may present a therapeutic target for intervention with a much longer window of opportunity compare to other neurological treatments. The challenge will be to find ways to selectively suppress the deleterious effects of microglial activation without compromising its beneficial functions. This review aims to provide an overview of the recent progress relating on the deleterious and beneficial effect of microglia in the setting of acute CNS injury and the potential therapeutic intervention against microglial activation to CNS injury.
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Affiliation(s)
- Masahito Kawabori
- Department of Neurology, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121, USA
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Wei X, Wan X, Zhao B, Hou J, Liu M, Cheng B. Propofol inhibits inflammation and lipid peroxidation following cerebral ischemia/reperfusion in rabbits. Neural Regen Res 2015; 7:837-41. [PMID: 25737711 PMCID: PMC4342711 DOI: 10.3969/j.issn.1673-5374.2012.11.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 03/24/2012] [Indexed: 11/18/2022] Open
Abstract
The present study established a rabbit model of global cerebral ischemia using the ‘six-vessel’ method, which was reperfused after 30 minutes of ischemia. Rabbits received intravenous injection of propofol at 5 mg/kg prior to ischemia and 20 mg/kg per hour after ischemia until samples were prepared. Results revealed that propofol inhibited serum interleukin-8, endothelin-1 and malondialdehyde increases and promoted plasma superoxide dismutase activity after cerebral ischemia/reperfusion. In addition, cerebral cortex edema was attenuated with little neuronal nuclear degeneration and pyknosis with propofol treatment. The cross-sectional area of neuronal nuclei was, however, increased following propofol treatment. These findings suggested that propofol could improve anti-oxidant activity and inhibit synthesis of inflammatory factors to exert a protective effect on cerebral ischemia/reperfusion injury.
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Affiliation(s)
- Xiaodong Wei
- Department of Anesthesiology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Xing Wan
- Department of Anesthesiology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Bo Zhao
- Department of Anesthesiology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Jiabao Hou
- Department of Anesthesiology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Min Liu
- Department of Anesthesiology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Bangchang Cheng
- Department of Cardiovascular Surgery, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
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Treatment with recombinant tissue plasminogen activator (r-TPA) induces neutrophil degranulation in vitro via defined pathways. Vascul Pharmacol 2014; 64:16-27. [PMID: 25530154 DOI: 10.1016/j.vph.2014.11.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 10/21/2014] [Accepted: 11/29/2014] [Indexed: 12/21/2022]
Abstract
Thrombolysis is recommended for reperfusion following acute ischemic stroke (AIS), but its effects on stroke-associated injury remain to be clarified. Here, we investigated the effects of recombinant tissue plasminogen activator (r-tPA) on neutrophil pathophysiology in vitro and in a case-control study with AIS patients submitted (n=60) or not (n=30) to thrombolysis. Patients underwent radiological and clinical examination as well as blood sampling at admission and after 1, 7 and 90days. In vitro, 30-min incubation with 0.1-1 mg/ml r-tPA induced neutrophil degranulation in different substrate cultures. Pre-incubation with kinase inhibitors and Western blot documented that degranulation was associated with activation of PI3K/Akt and ERK1/2 pathways in Teflon dishes and PI3K/Akt in polystyrene. In thrombolysed patients, a peak of neutrophil degranulation products (matrix metalloproteinase [MMP]-9, MMP-8, neutrophil elastase and myeloperoxidase), was shown during the first hours from drug administration. This was accompanied by serum augmentation of protective tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. An increased rate of haemorrhagic transformations on day 1 after AIS was shown in thrombolysed patients as compared to non-thrombolysed controls. In conclusion, r-tPA treatment was associated with in vitro neutrophil degranulation, indicating these cells as potential determinants in early haemorrhagic complications after thrombolysis in AIS patients.
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Huseynova S, Panakhova N, Orujova P, Hasanov S, Guliyev M, Orujov A. Elevated levels of serum sICAM-1 in asphyxiated low birth weight newborns. Sci Rep 2014; 4:6850. [PMID: 25358349 PMCID: PMC4215296 DOI: 10.1038/srep06850] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 10/10/2014] [Indexed: 12/02/2022] Open
Abstract
Perinatal hypoxia results in neuronal and endothelial cell damage. The main purpose of this study was to investigate the correlation of soluble intercellular adhesion molecule 1 (sICAM-1) expression and peripheral blood changes in perinatal asphyxia with neuronal injury markers in low birth weight (LBW) neonates. We compared the concentrations of serum sICAM-1, neuron-specific enolase (NSE) and antibodies specific for NR2 glutamate receptors in 29 asphyxiated and 20 control infants using standard enzyme immunoassay procedures. The mean total concentrations of sICAM-1 and neuron-specific proteins (NSE and NR2-specific antibodies) were higher in the asphyxiated infants than in the control infants. The serum sICAM-1 concentrations significantly correlated with Apgar scoring and with the pH and lactate data from capillary or arterial cord blood. No significant correlation between serum concentrations of neuron specific proteins and blood changes of asphyxia was found. Therefore, endothelial sICAM-1 expression levels might be accepted as an indicator of the severity of perinatal asphyxia in LBW infants.
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Affiliation(s)
- Saadat Huseynova
- Department of Neonatology, Azerbaijan Medical University, Baku, Azerbaijan
| | - Nushaba Panakhova
- Department of Neonatology, Azerbaijan Medical University, Baku, Azerbaijan
| | | | | | - Mehman Guliyev
- Department of Biochemistry, Azerbaijan Medical University, Baku, Azerbaijan
| | - Agil Orujov
- Department of Biochemistry, Azerbaijan Medical University, Baku, Azerbaijan
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Lehmann J, Härtig W, Seidel A, Füldner C, Hobohm C, Grosche J, Krueger M, Michalski D. Inflammatory cell recruitment after experimental thromboembolic stroke in rats. Neuroscience 2014; 279:139-54. [DOI: 10.1016/j.neuroscience.2014.08.023] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 07/28/2014] [Accepted: 08/17/2014] [Indexed: 10/24/2022]
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Zhang L, Kan ZC, Zhang XL, Fang H, Jiang WL. 8-O-acetyl shanzhiside methylester attenuates cerebral ischaemia/reperfusion injury through an anti-inflammatory mechanism in diabetic rats. Basic Clin Pharmacol Toxicol 2014; 115:481-7. [PMID: 24823762 DOI: 10.1111/bcpt.12266] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 04/30/2014] [Indexed: 12/21/2022]
Abstract
Inflammatory activation plays a vital role in the pathophysiological mechanisms of stroke and diabetes mellitus (DM), exerts the deleterious effects on the progression of the brain and leads to vascular damage in diabetic stroke. The objectives of this study were to investigate the effects of 8-O-acetyl shanzhiside methylester (ND01) on tumour necrosis factor-α (TNF-α)-stimulated SH-SY5Y cell line in vitro and the experimental ischaemic diabetic stroke model in vivo. TNF-α-stimulated SH-SY5Y cells were pre-incubated with ND01, then analysed protein expression. For in vivo experiment, the diabetic rats were subjected to middle cerebral artery occlusion (MCAO) for 30 min. followed by reperfusion for 23 hr. Treatment of SH-SY5Y cells with ND01 blocked TNF-α-induced nuclear transcription factor κB (NF-κB) activation and decreased high-mobility group box-1 (HMGB-1) expression. ND01 40 mg/kg demonstrated significant neuroprotective effect even after delayed administration at 4 hr after I/R. ND01 40 mg/kg attenuated the histopathological damage, decreased brain swelling, inhibited NF-κB activation and reduced HMGB-1 expression in ischaemic brain tissue. These data show that ND01 protects diabetic brain against I/R injury with a favourable therapeutic time-window by alleviating diabetic cerebral I/R injury and attenuating blood-brain barrier (BBB) breakdown, and its protective effects may involve HMGB-1 and NF-κB signalling pathway.
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Affiliation(s)
- Liang Zhang
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, China
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59
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Kuang X, Wang LF, Yu L, Li YJ, Wang YN, He Q, Chen C, Du JR. Ligustilide ameliorates neuroinflammation and brain injury in focal cerebral ischemia/reperfusion rats: involvement of inhibition of TLR4/peroxiredoxin 6 signaling. Free Radic Biol Med 2014; 71:165-175. [PMID: 24681253 DOI: 10.1016/j.freeradbiomed.2014.03.028] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Revised: 03/18/2014] [Accepted: 03/18/2014] [Indexed: 12/21/2022]
Abstract
Blocking TLR4/peroxiredoxin (Prx6) signaling is proposed to be a novel therapeutic strategy for ischemic stroke because extracellular Prx6 released from ischemic cells may act as an endogenous ligand for TLR4 and initiate destructive immune responses in ischemic brain. Our previous studies showed that ligustilide (LIG) exerted antineuroinflammatory and neuroprotective effects against ischemic insult, but the underlying mechanisms remain unclear. This study investigated whether the TLR4/Prx6 pathway is involved in the protective effect of LIG against postischemic neuroinflammation and brain injury induced by transient middle cerebral artery occlusion (MCAO) in rats. Intraperitoneal LIG administration (20 and 40 mg/kg/day) at reperfusion onset after MCAO resulted in a reduction of brain infarct size and improved neurological outcome over 72 h. LIG-induced neuroprotection was accompanied by improvement of neuropathological alterations, including neuron loss, astrocyte and microglia/macrophage activation, neutrophil and T-lymphocyte invasion, and regulation of inflammatory mediators expression. Moreover, LIG significantly inhibited the expression and extracellular release of Prx6 and activation of TLR4 signaling, reflected by decreased TLR4 expression, extracellular signal-regulated kinase 1/2 phosphorylation, and transcriptional activity of NF-κB and signal transducer and activator of transcription 3 in the ischemic brain. Our results demonstrate that LIG may provide an early and direct neuroprotection by inhibiting TLR4/Prx6 signaling and subsequent immunity and neuroinflammation after cerebral ischemia. These findings support the translational potential of blocking TLR4/Prx6 signaling for the treatment of ischemic stroke.
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Affiliation(s)
- Xi Kuang
- Department of Pharmacology, Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Liang-Fen Wang
- Department of Pharmacology, Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Lu Yu
- Department of Pharmacology, Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yong-Jie Li
- Department of Pharmacology, Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yan-Nan Wang
- Department of Pharmacology, Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Qian He
- Department of Pharmacology, Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Chu Chen
- Department of Pharmacology, Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Jun-Rong Du
- Department of Pharmacology, Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
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60
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Polymorphonuclear neutrophil in brain parenchyma after experimental intracerebral hemorrhage. Transl Stroke Res 2014; 5:554-61. [PMID: 24696130 DOI: 10.1007/s12975-014-0341-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 03/14/2014] [Accepted: 03/17/2014] [Indexed: 01/08/2023]
Abstract
Polymorphonuclear neutrophils (PMNs) infiltration into brain parenchyma after cerebrovascular accidents is viewed as a key component of secondary brain injury. Interestingly, a recent study of ischemic stroke suggests that after ischemic stroke, PMNs do not enter brain parenchyma and as such may cause no harm to the brain. Thus, the present study was designed to determine PMNs' behavior after intracerebral hemorrhage (ICH). Using the autologous blood injection model of ICH in rats and immunohistochemistry for PMNs and vascular components, we evaluated the temporal and spatial PMNs distribution in the ICH-affected brain. We found that, similar to ischemia, there is a robust increase in presence of PMNs in the ICH-injured tissue that lasts for at least 1 to 2 weeks. However, in contrast to what was suggested for ischemia, besides PMNs that stay in association with the vasculature, after ICH, we found abundance of intraparenchymal PMNs (with no obvious association with vessels) in the ICH core and hematoma border, especially between 1 and 7 days after the ictus. Interestingly, the increased presence of intraparenchymal PMNs after ICH coincided with the massive loss of microvascular integrity, suggesting vascular disruption as a potential cause of PMNs presence in the brain parenchyma. Our study indicates that in contrast to ischemic stroke, after ICH, PMNs target not only vascular compartment but also brain parenchyma in the affected brain. As such, it is possible that the pathogenic role and therapeutic implications of targeting PMNs after ICH could be different from these after ischemic stroke. Our work suggests the needs for more studies addressing the role of PMNs in ICH.
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Chu HX, Kim HA, Lee S, Moore JP, Chan CT, Vinh A, Gelderblom M, Arumugam TV, Broughton BRS, Drummond GR, Sobey CG. Immune cell infiltration in malignant middle cerebral artery infarction: comparison with transient cerebral ischemia. J Cereb Blood Flow Metab 2014; 34:450-9. [PMID: 24326388 PMCID: PMC3948121 DOI: 10.1038/jcbfm.2013.217] [Citation(s) in RCA: 166] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 11/04/2013] [Accepted: 11/05/2013] [Indexed: 12/29/2022]
Abstract
We tested whether significant leukocyte infiltration occurs in a mouse model of permanent cerebral ischemia. C57BL6/J male mice underwent either permanent (3 or 24 hours) or transient (1 or 2 hours+22- to 23-hour reperfusion) middle cerebral artery occlusion (MCAO). Using flow cytometry, we observed ∼15,000 leukocytes (CD45(+high) cells) in the ischemic hemisphere as early as 3 hours after permanent MCAO (pMCAO), comprising ∼40% lymphoid cells and ∼60% myeloid cells. Neutrophils were the predominant cell type entering the brain, and were increased to ∼5,000 as early as 3 hours after pMCAO. Several cell types (monocytes, macrophages, B lymphocytes, CD8(+) T lymphocytes, and natural killer cells) were also increased at 3 hours to levels sustained for 24 hours, whereas others (CD4(+) T cells, natural killer T cells, and dendritic cells) were unchanged at 3 hours, but were increased by 24 hours after pMCAO. Immunohistochemical analysis revealed that leukocytes typically had entered and widely dispersed throughout the parenchyma of the infarct within 3 hours. Moreover, compared with pMCAO, there were ∼50% fewer infiltrating leukocytes at 24 hours after transient MCAO (tMCAO), independent of infarct size. Microglial cell numbers were bilaterally increased in both models. These findings indicate that a profound infiltration of inflammatory cells occurs in the brain early after focal ischemia, especially without reperfusion.
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Affiliation(s)
- Hannah X Chu
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Hyun Ah Kim
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Seyoung Lee
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Jeffrey P Moore
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Christopher T Chan
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Antony Vinh
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Mathias Gelderblom
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Thiruma V Arumugam
- Department of Pharmacology, University of Queensland, St Lucia, Queensland, Australia
| | - Brad R S Broughton
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Grant R Drummond
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Christopher G Sobey
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
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An C, Shi Y, Li P, Hu X, Gan Y, Stetler RA, Leak RK, Gao Y, Sun BL, Zheng P, Chen J. Molecular dialogs between the ischemic brain and the peripheral immune system: dualistic roles in injury and repair. Prog Neurobiol 2013; 115:6-24. [PMID: 24374228 DOI: 10.1016/j.pneurobio.2013.12.002] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 11/28/2013] [Accepted: 12/17/2013] [Indexed: 12/26/2022]
Abstract
Immune and inflammatory responses actively modulate the pathophysiological processes of acute brain injuries such as stroke. Soon after the onset of stroke, signals such as brain-derived antigens, danger-associated molecular patterns (DAMPs), cytokines, and chemokines are released from the injured brain into the systemic circulation. The injured brain also communicates with peripheral organs through the parasympathetic and sympathetic branches of the autonomic nervous system. Many of these diverse signals not only activate resident immune cells in the brain, but also trigger robust immune responses in the periphery. Peripheral immune cells then migrate toward the site of injury and release additional cytokines, chemokines, and other molecules, causing further disruptive or protective effects in the ischemic brain. Bidirectional communication between the injured brain and the peripheral immune system is now known to regulate the progression of stroke pathology as well as tissue repair. In the end, this exquisitely coordinated crosstalk helps determine the fate of animals after stroke. This article reviews the literature on ischemic brain-derived signals through which peripheral immune responses are triggered, and the potential impact of these peripheral responses on brain injury and repair. Pharmacological strategies and cell-based therapies that target the dialog between the brain and peripheral immune system show promise as potential novel treatments for stroke.
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Affiliation(s)
- Chengrui An
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China
| | - Yejie Shi
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Educational and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA
| | - Peiying Li
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Xiaoming Hu
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Educational and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA
| | - Yu Gan
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Ruth A Stetler
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Educational and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | - Yanqin Gao
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China
| | - Bao-Liang Sun
- Key Laboratory of Cerebral Microcirculation in Universities of Shandong (Taishan Medical University), Department of Neurology, Affiliated Hospital of Taishan Medical University, Taian, Shandong 271000, China.
| | - Ping Zheng
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China.
| | - Jun Chen
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Educational and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA.
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63
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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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64
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Zgavc T, Hu TT, Van de Plas B, Vinken M, Ceulemans AG, Hachimi-Idrissi S, Sarre S, Michotte Y, Arckens L. Proteomic analysis of global protein expression changes in the endothelin-1 rat model for cerebral ischemia: Rescue effect of mild hypothermia. Neurochem Int 2013; 63:379-88. [DOI: 10.1016/j.neuint.2013.07.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 07/22/2013] [Accepted: 07/25/2013] [Indexed: 11/27/2022]
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65
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Altered circulating leukocytes and their chemokines in a clinical trial of therapeutic hypothermia for neonatal hypoxic ischemic encephalopathy*. Pediatr Crit Care Med 2013; 14:786-95. [PMID: 23897243 DOI: 10.1097/pcc.0b013e3182975cc9] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVES To determine systemic hypothermia's effect on circulating immune cells and their corresponding chemokines after hypoxic ischemic encephalopathy in neonates. DESIGN In our randomized, controlled, multicenter trial of systemic hypothermia in neonatal hypoxic ischemic encephalopathy, we measured total and leukocyte subset and serum chemokine levels over time in both hypothermia and normothermia groups, as primary outcomes for safety. SETTING Neonatal ICUs participating in a Neurological Disorders and Stroke sponsored clinical trial of therapeutic hypothermia. PATIENTS Sixty-five neonates with moderate to severe hypoxic ischemic encephalopathy within 6 hours after birth. INTERVENTIONS Patients were randomized to normothermia of 37°C or systemic hypothermia of 33°C for 48 hours. MEASUREMENTS AND MAIN RESULTS Complete and differential leukocyte counts and serum chemokines were measured every 12 hours for 72 hours. The hypothermia group had significantly lower median circulating total WBC and leukocyte subclasses than the normothermia group before rewarming, with a nadir at 36 hours. Only the absolute neutrophil count rebounded after rewarming in the hypothermia group. Chemokines, monocyte chemotactic protein-1 and interleukin-8, which mediate leukocyte chemotaxis as well as bone marrow suppression, were negatively correlated with their target leukocytes in the hypothermia group, suggesting active chemokine and leukocyte modulation by hypothermia. Relative leukopenia at 60-72 hours correlated with an adverse outcome in the hypothermia group. CONCLUSIONS Our data are consistent with chemokine-associated systemic immunosuppression with hypothermia treatment. In hypothermic neonates, persistence of lower leukocyte counts after rewarming is observed in infants with more severe CNS injury.
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Russek NS, Jensen MB. Histological quantification of brain tissue inflammatory cell infiltration after focal cerebral infarction: a systematic review. Int J Neurosci 2013; 124:160-5. [PMID: 23991681 DOI: 10.3109/00207454.2013.833509] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Ischemic stroke is a leading cause of death and disability, and current treatments to limit tissue injury and improve recovery are limited. Cerebral infarction is accompanied by intense brain tissue inflammation involving many inflammatory cell types that may cause both negative and positive effects on outcomes. Many potential neuroprotective and neurorestorative treatments may affect, and be affected by, this inflammatory cell infiltration, so that accurate quantification of this tissue response is needed. We performed a systematic review of histological methods to quantify brain tissue inflammatory cell infiltration after cerebral infarction. We found reports of multiple techniques to quantify different inflammatory cell types. We found no direct comparison studies and conclude that more research is needed to optimize the assessment of this important stroke outcome.
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Affiliation(s)
- Natanya S Russek
- Department of Neurology, University of Wisconsin , Madison, WI , USA
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Gu LJ, Xiong XX, Ito T, Lee J, Xu BH, Krams S, Steinberg GK, Zhao H. Moderate hypothermia inhibits brain inflammation and attenuates stroke-induced immunodepression in rats. CNS Neurosci Ther 2013; 20:67-75. [PMID: 23981596 DOI: 10.1111/cns.12160] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2013] [Revised: 07/14/2013] [Accepted: 07/15/2013] [Indexed: 01/07/2023] Open
Abstract
AIMS Stroke causes both brain inflammation and immunodepression. Mild-to-moderate hypothermia is known to attenuate brain inflammation, but its role in stroke-induced immunodepression (SIID) of the peripheral immune system remains unknown. This study investigated the effects in rats of moderate intra-ischemic hypothermia on SIID and brain inflammation. METHODS Stroke was induced in rats by permanent distal middle cerebral artery occlusion combined with transient bilateral common carotid artery occlusion, while body temperature was reduced to 30°C. Real-time PCR, flow cytometry, in vitro T-cell proliferation assays, in vivo delayed-type hypersensitivity (DTH) reaction and confocal microscopy were used to study SIID and brain inflammation. RESULTS Brief intra-ischemic hypothermia helped maintain certain leukocytes in the peripheral blood and spleen and enhanced T-cell proliferation in vitro and delayed-type hypersensitivity in vivo, suggesting that hypothermia reduces SIID. In contrast, in the brain, brief intra-Ischemic hypothermia inhibited mRNA expression of anti-inflammatory cytokine IL-10 and proinflammatory mediators INF-γ, TNF-α, IL-2, IL-1β and MIP-2. Brief intra-Ischemic hypothermia also attenuated the infiltration of lymphocytes, neutrophils (MPO(+) cells) and macrophages (CD68(+) cells) into the ischemic brain, suggesting that hypothermia inhibited brain inflammation. CONCLUSIONS Brief intra-ischemic hypothermia attenuated SIID and protected against acute brain inflammation.
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Affiliation(s)
- Li-Juan Gu
- Department of Neurosurgery, Stanford Stroke Center and Stanford Institute for Neuro-Innovation and Translational Neurosciences, Stanford University, Stanford, CA, USA; Department of Basic Medicine, Hangzhou Normal University, Hangzhou, China
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LI LH, WANG JS, KONG LY. Protective effects of Shengmai San and its three fractions on cerebral ischemia-reperfusion injury. Chin J Nat Med 2013; 11:222-30. [DOI: 10.1016/s1875-5364(13)60020-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Indexed: 11/26/2022]
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McCann SK, Roulston CL. NADPH Oxidase as a Therapeutic Target for Neuroprotection against Ischaemic Stroke: Future Perspectives. Brain Sci 2013; 3:561-98. [PMID: 24961415 PMCID: PMC4061864 DOI: 10.3390/brainsci3020561] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 03/14/2013] [Accepted: 03/20/2013] [Indexed: 12/11/2022] Open
Abstract
Oxidative stress caused by an excess of reactive oxygen species (ROS) is known to contribute to stroke injury, particularly during reperfusion, and antioxidants targeting this process have resulted in improved outcomes experimentally. Unfortunately these improvements have not been successfully translated to the clinical setting. Targeting the source of oxidative stress may provide a superior therapeutic approach. The NADPH oxidases are a family of enzymes dedicated solely to ROS production and pre-clinical animal studies targeting NADPH oxidases have shown promising results. However there are multiple factors that need to be considered for future drug development: There are several homologues of the catalytic subunit of NADPH oxidase. All have differing physiological roles and may contribute differentially to oxidative damage after stroke. Additionally, the role of ROS in brain repair is largely unexplored, which should be taken into consideration when developing drugs that inhibit specific NADPH oxidases after injury. This article focuses on the current knowledge regarding NADPH oxidase after stroke including in vivo genetic and inhibitor studies. The caution required when interpreting reports of positive outcomes after NADPH oxidase inhibition is also discussed, as effects on long term recovery are yet to be investigated and are likely to affect successful clinical translation.
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Affiliation(s)
- Sarah K McCann
- Stroke Injury and Repair Team, O'Brien Institute, St Vincent's Hospital, 42 Fitzroy St, Fitzroy, Melbourne 3065, Australia.
| | - Carli L Roulston
- Stroke Injury and Repair Team, O'Brien Institute, St Vincent's Hospital, 42 Fitzroy St, Fitzroy, Melbourne 3065, Australia.
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Yu L, Chen C, Wang LF, Kuang X, Liu K, Zhang H, Du JR. Neuroprotective effect of kaempferol glycosides against brain injury and neuroinflammation by inhibiting the activation of NF-κB and STAT3 in transient focal stroke. PLoS One 2013; 8:e55839. [PMID: 23437066 PMCID: PMC3577792 DOI: 10.1371/journal.pone.0055839] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 01/02/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Ischemic brain injury is associated with neuroinflammatory response, which essentially involves glial activation and neutrophil infiltration. Transcription factors nuclear factor-κB (NF-κB) and signal transducer and activator of transcription 3 (STAT3) contribute to ischemic neuroinflammatory processes and secondary brain injury by releasing proinflammatory mediators. Kaempferol-3-O-rutinoside (KRS) and kaempferol-3-O- glucoside (KGS) are primary flavonoids found in Carthamus tinctorius L. Recent studies demonstrated that KRS protected against ischemic brain injury. However, little is known about the underlying mechanisms. Flavonoids have been reported to have antiinflammatory properties. Herein, we explored the effects of KRS and KGS in a transient focal stroke model. METHODOLOGY/PRINCIPAL FINDINGS Rats were subjected to middle cerebral artery occlusion for 2 hours followed by 22 h reperfusion. An equimolar dose of KRS or KGS was administered i.v. at the beginning of reperfusion. The results showed that KRS or KGS significantly attenuated the neurological deficits, brain infarct volume, and neuron and axon injury, reflected by the upregulation of neuronal nuclear antigen-positive neurons and downregulation of amyloid precursor protein immunoreactivity in the ipsilateral ischemic hemisphere. Moreover, KRS and KGS inhibited the expression of OX-42, glial fibrillary acidic protein, phosphorylated STAT3 and NF-κB p65, and the nuclear content of NF-κB p65. Subsequently, these flavonoids inhibited the expression of tumor necrosis factor α, interleukin 1β, intercellular adhesion molecule 1, matrix metallopeptidase 9, inducible nitric oxide synthase, and myeloperoxidase. CONCLUSION/SIGNIFICANCE Our findings suggest that postischemic treatment with KRS or KGS prevents ischemic brain injury and neuroinflammation by inhibition of STAT3 and NF-κB activation and has the therapeutic potential for the neuroinflammation-related diseases, such as ischemic stroke.
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Affiliation(s)
- Lu Yu
- Key Laboratory of Drug Targeting and Drug Delivery Systems of Ministry of Education, Department of Pharmacology, West China School of Pharmacy, Sichuan University “985 Projects – Science and Technology Innovation Platform for Novel Drug Development and Translational Neuroscience Center”, Chengdu, China
- Luzhou Medical College, Luzhou, Sichuan, China
| | - Chu Chen
- Sichuan Academy of Chinese Medicine Sciences, Chengdu, China
| | - Liang-Fen Wang
- Key Laboratory of Drug Targeting and Drug Delivery Systems of Ministry of Education, Department of Pharmacology, West China School of Pharmacy, Sichuan University “985 Projects – Science and Technology Innovation Platform for Novel Drug Development and Translational Neuroscience Center”, Chengdu, China
| | - Xi Kuang
- Key Laboratory of Drug Targeting and Drug Delivery Systems of Ministry of Education, Department of Pharmacology, West China School of Pharmacy, Sichuan University “985 Projects – Science and Technology Innovation Platform for Novel Drug Development and Translational Neuroscience Center”, Chengdu, China
| | - Ke Liu
- Key Laboratory of Drug Targeting and Drug Delivery Systems of Ministry of Education, Department of Pharmacology, West China School of Pharmacy, Sichuan University “985 Projects – Science and Technology Innovation Platform for Novel Drug Development and Translational Neuroscience Center”, Chengdu, China
| | - Hao Zhang
- Key Laboratory of Drug Targeting and Drug Delivery Systems of Ministry of Education, Department of Pharmacology, West China School of Pharmacy, Sichuan University “985 Projects – Science and Technology Innovation Platform for Novel Drug Development and Translational Neuroscience Center”, Chengdu, China
| | - Jun-Rong Du
- Key Laboratory of Drug Targeting and Drug Delivery Systems of Ministry of Education, Department of Pharmacology, West China School of Pharmacy, Sichuan University “985 Projects – Science and Technology Innovation Platform for Novel Drug Development and Translational Neuroscience Center”, Chengdu, China
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Luan H, Kan Z, Xu Y, Lv C, Jiang W. Rosmarinic acid protects against experimental diabetes with cerebral ischemia: relation to inflammation response. J Neuroinflammation 2013; 10:28. [PMID: 23414442 PMCID: PMC3614882 DOI: 10.1186/1742-2094-10-28] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 01/30/2013] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Inflammatory activation plays a vital role in the pathophysiological mechanisms of stroke, exerting deleterious effects on the progression of tissue damage and may lead to the vascular damage in diabetes. The objectives of this study were to determine the effects of rosmarinic acid (RA) on a cultured neuronal cell line, SH-SY5Y in vitro and experimental ischemic diabetic stroke in vivo. METHODS For oxygen-glucose deprivation (OGD) and tumor necrosis factor-α (TNF-α) stimulated SH-SY5Y cell line in vitro, SH-SY5Y cells were incubated with RA. For an in vivo experiment, diabetic rats were subjected to middle cerebral artery occlusion (MACO) for 40 minutes followed by reperfusion for 23 h. RESULTS Treatment of SH-SY5Y cells with RA reduced the OGD-induced apoptosis and cytotoxicity, blocked TNF-α-induced nuclear transcription factor κB (NF-κB) activation, and decreased high-mobility group box1 (HMGB1) expression. At doses higher than 50 mg/kg, RA produced a significant neuroprotective potential in rats with ischemia and reperfusion (I/R). RA (50 mg/kg) demonstrated significant neuroprotective activity even after delayed administration at 1 h, 3 h and 5 h after I/R. RA 50 mg/kg attenuated histopathological damage, decreased brain edema, inhibited NF-κB activation and reduced HMGB1 expression. CONCLUSION These data show that RA protects the brain against I/R injury with a favorable therapeutic time-window by alleviating diabetic cerebral I/R injury and attenuating blood-brain barrier (BBB) breakdown, and its protective effects may involve HMGB1 and the NF-κB signaling pathway.
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Affiliation(s)
- Haiyun Luan
- School of Pharmaceutical Sciences and Institute of Material Medica, Binzhou Medical University, Yantai, 264003, People's Republic of China
| | - Zechun Kan
- School of Pharmaceutical Sciences and Institute of Material Medica, Binzhou Medical University, Yantai, 264003, People's Republic of China
| | - Yong Xu
- School of Pharmaceutical Sciences and Institute of Material Medica, Binzhou Medical University, Yantai, 264003, People's Republic of China
| | - Changjun Lv
- School of Pharmaceutical Sciences and Institute of Material Medica, Binzhou Medical University, Yantai, 264003, People's Republic of China
| | - Wanglin Jiang
- School of Pharmaceutical Sciences and Institute of Material Medica, Binzhou Medical University, Yantai, 264003, People's Republic of China
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Zgavc T, De Geyter D, Ceulemans AG, Stoop W, Hachimi-Idrissi S, Michotte Y, Sarre S, Kooijman R. Mild hypothermia reduces activated caspase-3 up to 1 week after a focal cerebral ischemia induced by endothelin-1 in rats. Brain Res 2013; 1501:81-8. [PMID: 23357472 DOI: 10.1016/j.brainres.2013.01.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 01/15/2013] [Accepted: 01/19/2013] [Indexed: 12/27/2022]
Abstract
Hypothermia is a promising neuroprotective therapy that has been shown to reduce apoptosis after an ischemic insult. This study evaluated the effect of mild hypothermia on activated caspase-3 up to 1 week after the induction of a stroke. Endothelin-1 (Et-1) was used to elicit transient focal cerebral ischemia in rats. Twenty minutes after the ischemic insult, a state of mild hypothermia (33°C) was imposed for a duration of 2h. The functional outcome, infarct volume and activated caspase-3 immunoreactivity (IR) were assessed at 8, 24 and 72h, and one week after the insult. During the experiment the cerebral blood flow (CBF) was measured via Laser Doppler Flowmetry. Hypothermia improved the neurological outcome at all of the time points studied compared to the normothermic group, and was associated with a reduction in infarct volume. In both groups, activated caspase-3 IR peaked 24h after the Et-1 induced insult and hypothermia significantly reduced the number of apoptotic cells at 8h, 24h and 1 week after ischemia. Furthermore, the hypothermic treatment did not affect the CBF in the Et-1 model. These findings indicate that in the Et-1 model, hypothermia exerts a long lasting effect on stroke-induced apoptosis.
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Affiliation(s)
- Tine Zgavc
- Department of Pharmaceutical Chemistry and Drug Analysis, Center for Neuroscience, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium.
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Weston RM, Lin B, Dusting GJ, Roulston CL. Targeting oxidative stress injury after ischemic stroke in conscious rats: limited benefits with apocynin highlight the need to incorporate long term recovery. Stroke Res Treat 2013; 2013:648061. [PMID: 23401848 PMCID: PMC3557625 DOI: 10.1155/2013/648061] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Accepted: 12/14/2012] [Indexed: 02/02/2023] Open
Abstract
NADPH oxidase is a major source of superoxide anion following stroke and reperfusion. This study evaluated the effects of apocynin, a known antioxidant and inhibitor of Nox2 NADPH, on neuronal injury and cell-specific responses to stroke induced in the conscious rat. Apocynin treatment (50 mg/kg i.p.) commencing 1 hour prior to stroke and 24 and 48 hours after stroke significantly reduced infarct volume in the cortex by ~ 60%, but had no effect on striatal damage or neurological deficits. In situ detection of reactive oxygen species (ROS) using dihydroethidium fluorescence revealed that increased ROS detected in OX-42 positive cells following ischemia was reduced in apocynin-treated rats by ~ 51%, but surprisingly increased in surrounding NeuN positive cells of the same rats by ~ 27%, in comparison to the contralateral hemisphere. Reduced ROS from activated microglia/macrophages treated with apocynin was associated with reduced Nox2 immunoreactivity without change to the number of cells. These findings confirm the protective effects of apocynin and indicate a novel mechanism via reduced Nox2 expression. We also reveal compensatory changes in neuronal ROS generation as a result of Nox2 inhibition and highlight the need to assess long term individual cell responses to inhibitors of oxidative stress.
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Affiliation(s)
- Robert M. Weston
- Stroke Injury and Repair Team, O'Brien Institute, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia
| | - Bin Lin
- Stroke Injury and Repair Team, O'Brien Institute, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia
| | - Gregory J. Dusting
- Cytoprotection Pharmacology Program, Centre for Eye Research, The Royal Eye and Ear Hospital Victoria, Melbourne, Victoria, Australia
- Department of Ophthalmology, Faculty of Medicine, The University of Melbourne, Victoria, Australia
| | - Carli L. Roulston
- Stroke Injury and Repair Team, O'Brien Institute, St Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia
- Department of Surgery, Faculty of Medicine, The University of Melbourne, Victoria, Australia
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Raza S, Khan M, Ahmad A, Ashafaq M, Islam F, Wagner A, Safhi M, Islam F. Neuroprotective effect of naringenin is mediated through suppression of NF-κB signaling pathway in experimental stroke. Neuroscience 2013; 230:157-71. [DOI: 10.1016/j.neuroscience.2012.10.041] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 10/18/2012] [Accepted: 10/19/2012] [Indexed: 10/27/2022]
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Ju C, Hwang S, Cho GS, Kondaji G, Song S, Prather PL, Choi Y, Kim WK. Differential anti-ischemic efficacy and therapeutic time window of trans- and cis-hinokiresinols: stereo-specific antioxidant and anti-inflammatory activities. Neuropharmacology 2013; 67:465-75. [PMID: 23287539 DOI: 10.1016/j.neuropharm.2012.12.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 12/16/2012] [Accepted: 12/17/2012] [Indexed: 11/30/2022]
Abstract
During cerebral ischemia, neurons are injured by various mechanisms including excitotoxicity, oxidative stress, and inflammatory responses. Thus, pharmacological manipulation of multiple cytotoxic pathways has been pursued for the treatment of ischemic injury. Cis-hinokiresinol, a naturally occurring phenylpropanoid, was previously reported to possess anti-oxidant, anti-inflammatory and estrogen-like activities. In the present study, we investigated anti-ischemic effects of trans- and cis-hinokiresinols using in vitro as well as in vivo experimental models. The ORAC and DPPH assays showed that two isomers had similar free radical scavenging activities. However, only trans-hinokiresinol significantly decreased neuronal injury in cultured cortical neurons exposed to oxygen-glucose deprivation (75 min) followed by re-oxygenation (9 h). The differential neuroprotective effect could be due to the stereo-specific augmentation of Cu/Zn-SOD activity by trans-hinokiresinol, when compared with cis-hinokiresinol. Similarly, in rats subjected to transient middle cerebral artery occlusion (1.5 h) followed by 24-h reperfusion, pre-ischemic treatment with trans-hinokiresinol, but not with cis-isomer, reduced cerebral infarct volume. Interestingly, however, post-ischemic treatment with both hinokiresinols (2 and 7 h after onset of ischemia) significantly reduced cerebral infarct. When administered after onset of ischemia, trans-hinokiresinol, but not its cis-isomer reduced nitrotyrosine immunoreactivity in ischemic regions. In contrast, both hinokiresinols suppressed neutrophil infiltration and IL-1β release to a similar extent. The observed differential anti-oxidant, but comparable anti-inflammatory, activities may explain the stereo-specific anti-ischemic activities and different therapeutic time windows of the hinokiresinols examined. More detailed delineation of the anti-ischemic mechanism(s) of hinokiresinols may provide a better strategy for development of efficacious regimens for cerebral ischemic stroke.
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Affiliation(s)
- Chung Ju
- Department of Neuroscience, College of Medicine, Korea University, Anamdong-5-ga, Seongbuk-gu, Seoul 136-705, Republic of Korea
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Sevoflurane and Isoflurane Preconditioning Provides Neuroprotection by Inhibition of Apoptosis-related mRNA Expression in a Rat Model of Focal Cerebral Ischemia. J Neurosurg Anesthesiol 2012; 24:336-44. [DOI: 10.1097/ana.0b013e318266791e] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Abstract
INTRODUCTION Stroke is the third leading cause of death and a major cause of long-term disability in the adult population. Growing evidence suggests that inflammation may play an important role in the evolution of stroke. Because Rho-associated coiled-coil containing kinases (ROCKs) are important mediators of inflammation, they may contribute to stroke and stroke recovery. AREAS COVERED The pathophysiological role of ROCKs in mediating inflammation at different phases of stroke, and the therapeutic opportunities for stroke prevention and stroke treatment with ROCK inhibitors will be discussed. EXPERT OPINION Inflammation is a double-edged sword during the evolution of stroke. Immunomodulation might provide a novel therapeutic approach for stroke prevention and stroke treatment. ROCK plays an important role in mediating the inflammatory response following vascular injury as well as platelet activation and thrombus formation. ROCK inhibitors have been shown to be beneficial in stroke prevention, acute neuroprotection and chronic stroke recovery by affecting inflammatory-mediated platelet and endothelial function, smooth muscle contraction and neuronal regeneration. Thus, ROCK-mediated inflammation could be a potential therapeutic target for stroke prevention and stroke treatment. However, the mechanism by which ROCKs regulate the inflammatory response is unclear, and the role of the two ROCK isoforms in stroke and stroke recovery remains to be determined.
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Affiliation(s)
- Qing Mei Wang
- Spaulding Rehabilitation Hospital, Department of Physical Medicine and Rehabilitation, Boston, MA, USA
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Zgavc T, Ceulemans AG, Hachimi-Idrissi S, Kooijman R, Sarre S, Michotte Y. The neuroprotective effect of post ischemic brief mild hypothermic treatment correlates with apoptosis, but not with gliosis in endothelin-1 treated rats. BMC Neurosci 2012; 13:105. [PMID: 22920191 PMCID: PMC3502503 DOI: 10.1186/1471-2202-13-105] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Accepted: 08/21/2012] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Stroke remains one of the most common diseases with a serious impact on quality of life but few effective treatments exist. Mild hypothermia (33°C) is a promising neuroprotective therapy in stroke management. This study investigated whether a delayed short mild hypothermic treatment is still beneficial as neuroprotective strategy in the endothelin-1 (Et-1) rat model for a transient focal cerebral ischemia. Two hours of mild hypothermia (33°C) was induced 20, 60 or 120 minutes after Et-1 infusion. During the experiment the cerebral blood flow (CBF) was measured via Laser Doppler Flowmetry in the striatum, which represents the core of the infarct. Functional outcome and infarct volume were assessed 24 hours after the insult. In this sub-acute phase following stroke induction, the effects of the hypothermic treatment on apoptosis, phagocytosis and astrogliosis were assessed as well. Apoptosis was determined using caspase-3 immunohistochemistry, phagocytic cells were visualized by CD-68 expression and astrogliosis was studied by glial fibrillary acidic protein (GFAP) staining. RESULTS Cooling could be postponed up to 1 hour after the onset of the insult without losing its positive effects on neurological deficit and infarct volume. These results correlated with the caspase-3 staining. In contrast, the increased CD-68 expression post-stroke was reduced in the core of the insult with all treatment protocols. Hypothermia also reduced the increased levels of GFAP staining, even when it was delayed up to 2 hours after the insult. The study confirmed that the induction of the hypothermia treatment in the Et-1 model does not affect the CBF. CONCLUSIONS These data indicate that in the Et-1 rat model, a short mild hypothermic treatment delayed for 1 hour is still neuroprotective and correlates with apoptosis. At the same time, hypothermia also establishes a lasting inhibitory effect on the activation of astrogliosis.
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Affiliation(s)
- Tine Zgavc
- Department of Pharmaceutical Chemistry and Drug Analysis, Center for Neuroscience, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
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Michalski D, Heindl M, Kacza J, Laignel F, Küppers-Tiedt L, Schneider D, Grosche J, Boltze J, Löhr M, Hobohm C, Härtig W. Spatio-temporal course of macrophage-like cell accumulation after experimental embolic stroke depending on treatment with tissue plasminogen activator and its combination with hyperbaric oxygenation. Eur J Histochem 2012; 56:e14. [PMID: 22688295 DOI: 10.4081/ejh.2012.14] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2011] [Revised: 02/01/2012] [Accepted: 02/03/2012] [Indexed: 01/01/2023] Open
Abstract
Inflammation following ischaemic stroke attracts high priority in current research, particularly using human-like models and long-term observation periods considering translational aspects. The present study aimed on the spatio-temporal course of macrophage-like cell accumulation after experimental thromboembolic stroke and addressed microglial and astroglial reactions in the ischaemic border zone. Further, effects of tissue plasminogen activator (tPA) as currently best treatment for stroke and the potentially neuroprotective co-administration of hyperbaric oxygen (HBO) were investigated. Rats underwent middle cerebral artery occlusion and were assigned to control, tPA or tPA+HBO. Twenty-four hours, 7, 14 and 28 days were determined as observation time points. The accumulation of macrophage-like cells was semiquantitatively assessed by CD68 staining in the ischaemic area and ischaemic border zone, and linked to the clinical course. CD11b, ionized calcium binding adaptor molecule 1 (Iba), glial fibrillary acidic protein (GFAP) and Neuronal Nuclei (NeuN) were applied to reveal delayed glial and neuronal alterations. In all groups, the accumulation of macrophage-like cells increased distinctly from 24 hours to 7 days post ischaemia. tPA+HBO tended to decrease macrophage-like cell accumulation at day 14 and 28. Overall, a trend towards an association of increased accumulation and pronounced reduction of the neurological deficit was found. Concerning delayed inflammatory reactions, an activation of microglia and astrocytes with co-occurring neuronal loss was observed on day 28. Thereby, astrogliosis was found circularly in contrast to microglial activation directly in the ischaemic area. This study supports previous data on long-lasting inflammatory processes following experimental stroke, and additionally provides region-specific details on glial reactions. The tendency towards a decreasing macrophage-like cell accumulation after tPA+HBO needs to be discussed critically since neuroprotective properties were recently ascribed to long-term inflammatory processes.
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Affiliation(s)
- D Michalski
- Department of Neurology, University of Leipzig, Germany.
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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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81
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Chauhan A, Sharma U, Reeta KH, Jagannathan NR, Mehra RD, Gupta YK. Neuroimaging, biochemical and cellular evidence of protection by mycophenolate mofetil on middle cerebral artery occlusion induced injury in rats. Eur J Pharmacol 2012; 684:71-8. [PMID: 22487058 DOI: 10.1016/j.ejphar.2012.03.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2011] [Revised: 03/09/2012] [Accepted: 03/22/2012] [Indexed: 10/28/2022]
Abstract
Stroke is a major cause of mortality and disability worldwide. Presently, recombinant tissue plasminogen activator is the only approved drug for the management of acute ischemic stroke. However, it has limitations like narrow therapeutic window and increased risk of intracranial hemorrhage. In previous studies, immunosuppressive agents such as cyclosporine A and tacrolimus have shown neuroprotection by improving neurological functions and infarct volume in models of ischemic stroke. Therefore, the present study was designed to evaluate the effect of mycophenolate mofetil (MMF) on the cerebral ischemic injury in the middle cerebral artery occlusion (MCAo) model in rats. MCAo was carried out in male Wistar rats by inserting an intraluminal thread. One hour after MCAo, the animals were treated with MMF (50, 100, 200mg/kg, i.p.). Reperfusion was done after 2h of occlusion. Thirty minutes after reperfusion, animals were subjected to diffusion-weighted magnetic resonance imaging for assessment of neuroprotective effect of MMF. Twenty four hours after MCAo, motor performance was assessed and the animals were euthanized for estimation of brain malondialdehyde, glutathione, myeloperoxidase and nitric oxide levels. The effect of MMF on apoptosis was also evaluated. MMF significantly attenuated the percent infarct area, apparent diffusion coefficient and signal intensity as compared to a vehicle treated group. Treatment with MMF prevented the motor impairment and significantly reversed the changes in levels of malondialdehyde, glutathione, myeloperoxidase and nitric oxide. MMF treatment significantly reduced the apoptosis. Data of the present study indicate neuroprotective effect of MMF in the experimental model of ischemic stroke.
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Affiliation(s)
- Anjali Chauhan
- Neuropharmacology Laboratory, Department of Pharmacology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
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82
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Differential regulation of Nedd4 ubiquitin ligases and their adaptor protein Ndfip1 in a rat model of ischemic stroke. Exp Neurol 2012; 235:326-35. [PMID: 22417925 DOI: 10.1016/j.expneurol.2012.02.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 02/20/2012] [Accepted: 02/25/2012] [Indexed: 01/31/2023]
Abstract
Ubiquitin-modification of proteins by E3 ubiquitin ligases is an important post-translational mechanism implicated in neuronal survival and injury following cerebral ischemia. However, of the 500 or so E3s thought to be present in mammalian cells, very few specific E3s have been identified and associated with brain ischemia. Here, we demonstrate endogenous induction of HECT-type E3 ligases of the Nedd4 family and their adaptor Nedd4-family interacting protein 1 (Ndfip1) following transient focal cerebral ischemia in rats. Ndfip1 is upregulated in surviving cortical neurons and its neuroprotective activity is correlated with Nedd4-2 upregulation, but not two other Nedd4 family members examined (Nedd4-1 and Itch). Immunoprecipitation assays confirmed biochemical binding of Ndfip1 with Nedd4-2 in the brain, with or without ischemic stroke, indicating their endogenous interaction. While Ndfip1 and Itch have been previously shown to interact outside of the nervous system, ischemic induction of Itch in the present study was associated with cellular survival independent of Ndfip1. Together, these findings demonstrate specific and differential regulation of Nedd4 family E3 ligases under ischemic conditions, and identify two E3 ligases and their adaptor that potentially regulate ubiquitination in ischemic stroke to provide neuroprotection.
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83
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Ortega FJ, Gimeno-Bayon J, Espinosa-Parrilla JF, Carrasco JL, Batlle M, Pugliese M, Mahy N, Rodríguez MJ. ATP-dependent potassium channel blockade strengthens microglial neuroprotection after hypoxia-ischemia in rats. Exp Neurol 2012; 235:282-96. [PMID: 22387180 DOI: 10.1016/j.expneurol.2012.02.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 01/23/2012] [Accepted: 02/16/2012] [Indexed: 10/28/2022]
Abstract
Stroke causes CNS injury associated with strong fast microglial activation as part of the inflammatory response. In rat models of stroke, sulphonylurea receptor blockade with glibenclamide reduced cerebral edema and infarct volume. We postulated that glibenclamide administered during the early stages of stroke might foster neuroprotective microglial activity through ATP-sensitive potassium (K(ATP)) channel blockade. We found in vitro that BV2 cell line showed upregulated expression of K(ATP) channel subunits in response to pro-inflammatory signals and that glibenclamide increases the reactive morphology of microglia, phagocytic capacity and TNFα release. Moreover, glibenclamide administered to rats 6, 12 and 24h after transient Middle Cerebral Artery occlusion improved neurological outcome and preserved neurons in the lesioned core three days after reperfusion. Immunohistochemistry with specific markers to neuron, astroglia, microglia and lymphocytes showed that resident amoeboid microglia are the main cell population in that necrotic zone. These reactive microglial cells express SUR1, SUR2B and Kir6.2 proteins that assemble in functional K(ATP) channels. These findings provide that evidence for the key role of K(ATP) channels in the control of microglial reactivity are consistent with a microglial effect of glibenclamide into the ischemic brain and suggest a neuroprotective role of microglia in the early stages of stroke.
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Affiliation(s)
- F J Ortega
- Unitat de Bioquímica i Biologia Molecular, Facultat de Medicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Barcelona, Spain
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84
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Chauhan A, Sharma U, Jagannathan N, Reeta K, Gupta YK. Rapamycin protects against middle cerebral artery occlusion induced focal cerebral ischemia in rats. Behav Brain Res 2011; 225:603-9. [DOI: 10.1016/j.bbr.2011.08.035] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 08/21/2011] [Accepted: 08/24/2011] [Indexed: 11/28/2022]
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85
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Ceulemans AG, Hernot S, Zgavc T, Caveliers V, Hachimi-Idrissi S, Sarre S, Lahoutte T, Michotte Y. Serial semiquantitative imaging of brain damage using micro-SPECT and micro-CT after endothelin-1-induced transient focal cerebral ischemia in rats. J Nucl Med 2011; 52:1987-92. [PMID: 22049462 DOI: 10.2967/jnumed.110.085902] [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
UNLABELLED In this study, we validated the use of (99m)Tc-hexamethylpropyleneamine oxime ((99m)Tc-HMPAO) micro-SPECT combined with micro-CT for semiquantification of the infarct size after an experimental stroke in rats and compared our observations with those obtained from histology. This imaging strategy was applied to measure the longitudinal effect of mild hypothermia on the progression of brain damage after stroke in rats. METHODS The endothelin-1 model was used to elicit a transient focal cerebral ischemia in rats. This resulted in a reproducible insult in which the core is represented by the striatum and the penumbra by the cortex. Micro-SPECT and micro-CT images were taken at 1, 3, and 7 d after infusion of endothelin-1 and compared with those taken before the insult. After the last acquisition, rats were sacrificed and the infarct volume was determined via Nissl staining. The results obtained with micro-SPECT and micro-CT were compared with histology at the same time points. Mild hypothermia (33°C) was induced for 2 h, starting 20 min after the insult. RESULTS Brain damage was estimated using micro-SPECT and micro-CT and was reproducible with minimal interobserver variability. Normothermic stroke rats had reduced (99m)Tc-HMPAO uptake at 1 and 3 d after the insult, whereas hypothermia improved damage after stroke. These findings corroborate with histology at the same time points. At 1 wk after the insult, no reduction of radioactive uptake was observed in any treatment group. CONCLUSION Micro-SPECT and micro-CT allow quick and reproducible semiquantification of brain damage as an interesting alternative to histology to measure the extent of infarcted tissue in small animals after stroke.
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Affiliation(s)
- An-Gaëlle Ceulemans
- Department of Pharmaceutical Chemistry and Drug Analysis, FASC, Center for Neuroscience, Vrije Universiteit Brussel, Brussels, Belgium
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86
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Lee B, Clarke D, Al Ahmad A, Kahle M, Parham C, Auckland L, Shaw C, Fidanboylu M, Orr AW, Ogunshola O, Fertala A, Thomas SA, Bix GJ. Perlecan domain V is neuroprotective and proangiogenic following ischemic stroke in rodents. J Clin Invest 2011; 121:3005-23. [PMID: 21747167 DOI: 10.1172/jci46358] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Accepted: 05/18/2011] [Indexed: 12/27/2022] Open
Abstract
Stroke is the leading cause of long-term disability and the third leading cause of death in the United States. While most research thus far has focused on acute stroke treatment and neuroprotection, the exploitation of endogenous brain self-repair mechanisms may also yield therapeutic strategies. Here, we describe a distinct type of stroke treatment, the naturally occurring extracellular matrix fragment of perlecan, domain V, which we found had neuroprotective properties and enhanced post-stroke angiogenesis, a key component of brain repair, in rodent models of stroke. In both rat and mouse models, Western blot analysis revealed elevated levels of perlecan domain V. When systemically administered 24 hours after stroke, domain V was well tolerated, reached infarct and peri-infarct brain vasculature, and restored stroke-affected motor function to baseline pre-stroke levels in these multiple stroke models in both mice and rats. Post-stroke domain V administration increased VEGF levels via a mechanism involving brain endothelial cell α5β1 integrin, and the subsequent neuroprotective and angiogenic actions of domain V were in turn mediated via VEGFR. These results suggest that perlecan domain V represents a promising approach for stroke treatment.
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Affiliation(s)
- Boyeon Lee
- Department of Molecular and Cellular Medicine, Texas A&M College of Medicine, College Station, Texas 77843, USA
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87
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Ceulemans AG, Zgavc T, Kooijman R, Hachimi-Idrissi S, Sarre S, Michotte Y. Mild hypothermia causes differential, time-dependent changes in cytokine expression and gliosis following endothelin-1-induced transient focal cerebral ischemia. J Neuroinflammation 2011; 8:60. [PMID: 21627837 PMCID: PMC3127770 DOI: 10.1186/1742-2094-8-60] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 05/31/2011] [Indexed: 12/28/2022] Open
Abstract
Background Stroke is an important cause of morbidity and mortality and few therapies exist thus far. Mild hypothermia (33°C) is a promising neuroprotective strategy to improve outcome after ischemic stroke. However, its complete mechanism of action has not yet been fully elaborated. This study is the first to investigate whether this neuroprotection occurs through modulation of the neuroinflammatory response after stroke in a time-dependent manner. Methods The Endothelin-1 (Et-1) model was used to elicit a transient focal cerebral ischemia in male Wistar rats. In this model, the core and penumbra of the insult are represented by the striatum and the cortex respectively. We assessed the effects of 2 hours of hypothermia, started 20 minutes after Et-1 injection on neurological outcome and infarct volume. Furthermore, pro- and anti-inflammatory cytokine expression was determined using ELISA. Microgliosis and astrogliosis were investigated using CD-68 and GFAP staining respectively. All parameters were determined 8, 24, 72 hours and 1 week after the administration of Et-1. Results Et-1 infusion caused neurological deficit and a reproducible infarct size which increased up to 3 days after the insult. Both parameters were significantly reduced by hypothermia. The strongest reduction in infarct volume with hypothermia, at 3 days, corresponded with increased microglial activation. Reducing the brain temperature affected the stroke induced increase in interleukin-1β and tumor necrosis factor α in the striatum, 8 hours after its induction, but not at later time points. Transforming growth factor β increased as a function of time after the Et-1-induced insult and was not influenced by cooling. Hypothermia reduced astrogliosis at 1 and 3 days after stroke onset. Conclusions The beneficial effects of hypothermia after stroke on infarct volume and functional outcome coincide with a time-dependent modulation of the cytokine expression and gliosis.
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Affiliation(s)
- An-Gaëlle Ceulemans
- Department of Pharmaceutical Chemistry and Drug Analysis, Center for Neuroscience, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
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88
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Decreased myeloperoxidase expressing cells in the aged rat brain after excitotoxic damage. Exp Gerontol 2011; 46:723-30. [PMID: 21601629 DOI: 10.1016/j.exger.2011.05.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 04/12/2011] [Accepted: 05/06/2011] [Indexed: 12/11/2022]
Abstract
Brain aging is associated to several morphological and functional alterations that influence the evolution and outcome of CNS damage. Acute brain injury such as an excitotoxic insult induces initial tissue damage followed by associated inflammation and oxidative stress, partly attributed to neutrophil recruitment and the expression of oxidative enzymes such as myeloperoxidase (MPO), among others. However, to date, very few studies have focused on how age can influence neutrophil infiltration after acute brain damage. Therefore, to evaluate the age-dependent pattern of neutrophil cell infiltration following an excitotoxic injury, intrastriatal injection of N-methyl-d-aspartate was performed in young and aged male Wistar rats. Animals were sacrificed at different times between 12h post-lesion (hpl) to 14 days post-lesion (dpl). Cryostat sections were processed for myeloperoxidase (MPO) immunohistochemistry, and double labeling for either neuronal cells (NeuN), astrocytes (GFAP), perivascular macrophages (ED-2), or microglia/macrophages (tomato lectin histochemistry). Our observations showed that MPO + cells were observed in the injured striatum from 12 hpl (when maximum values were found) until 7 dpl, when cell density was strongly diminished. However, at all survival times analyzed, the overall density of MPO + cells was lower in the aged versus the adult injured striatum. MPO + cells were mainly identified as neutrophils (especially at 12 hpl and 1 dpl), but it should be noted that MPO + neurons and microglia/macrophages were also found. MPO + neurons were most commonly observed at 12 hpl and reduced in the aged. MPO + microglia/macrophages were the main population expressing MPO from 3 dpl, when density was also reduced in aged subjects. These results point to neutrophil infiltration as another important factor contributing to the different responses of the adult and aged brain to damage, highlighting the need of using aged animals for the study of acute age-related brain insults.
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89
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Tureyen K, Bowen K, Liang J, Dempsey RJ, Vemuganti R. Exacerbated brain damage, edema and inflammation in type-2 diabetic mice subjected to focal ischemia. J Neurochem 2011; 116:499-507. [PMID: 21133923 DOI: 10.1111/j.1471-4159.2010.07127.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
One of the limiting factors in stroke therapeutic development is the use of animal models that do not well represent the underlying medical conditions of patients. In humans, diabetes increases the risk of stroke incidence as well as post-stroke mortality. To understand the mechanisms that render diabetics to increased brain damage, we evaluated the effect of transient middle cerebral artery occlusion in adult db/db mice. The db/db mouse is a model of type-2 diabetes with four times higher blood sugar than its normoglycemic genetic control(db/+ mouse). Following transient middle cerebral artery occlusion, the db/db mice showed significantly higher mortality, bigger infarcts, increased cerebral edema, worsened neurological status compared to db/+ mice. The db/db mice also showed significantly higher post-ischemic inflammatory markers (ICAM1(+) capillaries, extravasated macrophages/neutrophils and exacerbated proinflammatory gene expression) compared to db/+ mice. In addition, the post-ischemic neuroprotective heat-shock chaperone gene expression was curtailed in the db/db compared to db/+ mice.
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Affiliation(s)
- Kudret Tureyen
- Department of Neurological Surgery, University of Wisconsin, Madison, WI 53792, USA
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90
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Cernak I. The importance of systemic response in the pathobiology of blast-induced neurotrauma. Front Neurol 2010; 1:151. [PMID: 21206523 PMCID: PMC3009449 DOI: 10.3389/fneur.2010.00151] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Accepted: 11/24/2010] [Indexed: 11/13/2022] Open
Abstract
Due to complex injurious environment where multiple blast effects interact with the body parallel, blast-induced neurotrauma is a unique clinical entity induced by systemic, local, and cerebral responses. Activation of autonomous nervous system; sudden pressure increase in vital organs such as lungs and liver; and activation of neuroendocrine-immune system are among the most important mechanisms that contribute significantly to molecular changes and cascading injury mechanisms in the brain. It has been hypothesized that vagally mediated cerebral effects play a vital role in the early response to blast: this assumption has been supported by experiments where bilateral vagotomy mitigated bradycardia, hypotension, and apnea, and also prevented excessive metabolic alterations in the brain of animals exposed to blast. Clinical experience suggests specific blast-body-nervous system interactions such as (1) direct interaction with the head either through direct passage of the blast wave through the skull or by causing acceleration and/or rotation of the head; and (2) via hydraulic interaction, when the blast overpressure compresses the abdomen and chest, and transfers its kinetic energy to the body's fluid phase, initiating oscillating waves that traverse the body and reach the brain. Accumulating evidence suggests that inflammation plays important role in the pathogenesis of long-term neurological deficits due to blast. These include memory decline, motor function and balance impairments, and behavioral alterations, among others. Experiments using rigid body- or head protection in animals subjected to blast showed that head protection failed to prevent inflammation in the brain or reduce neurological deficits, whereas body protection was successful in alleviating the blast-induced functional and morphological impairments in the brain.
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Affiliation(s)
- Ibolja Cernak
- Biomedicine Business Area, National Security Technology Department, Johns Hopkins University Applied Physics Laboratory Laurel, MD, USA
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91
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Downes CE, Crack PJ. Neural injury following stroke: are Toll-like receptors the link between the immune system and the CNS? Br J Pharmacol 2010; 160:1872-88. [PMID: 20649586 DOI: 10.1111/j.1476-5381.2010.00864.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The CNS can exhibit features of inflammation in response to injury, infection or disease, whereby resident cells generate inflammatory mediators, including cytokines, prostaglandins, free radicals and complement, chemokines and adhesion molecules that recruit immune cells, and activate glia and microglia. Cerebral ischaemia triggers acute inflammation, which exacerbates primary brain damage. The regulation of inflammation after stroke is multifaceted and comprises vascular effects, distinct cellular responses, apoptosis and chemotaxis. There are many cell types that are affected including neurons, astrocytes, microglia and endothelial cells, all responding to the resultant neuroinflammation in different ways. Over the past 20 years, researchers examining brain tissue at various time intervals after stroke observed the presence of inflammatory cells, neutrophils and monocytes at the site of injury, as well as the activation of endogenous glia and microglia. This review examines the involvement of these cells in the progression of neural injury and proposes that the Toll-like receptors (TLRs) are likely to be an integral component in the communication between the CNS and the periphery. This receptor system is the archetypal pathogen sensing receptor system and its presence and signalling in the brain following neural injury suggests a more diverse role. We propose that the TLR system presents excellent pharmacological targets for the design of a new generation of therapeutic agents to modulate the inflammation that accompanies neural injury.
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Affiliation(s)
- Catherine E Downes
- Department of Pharmacology, The University of Melbourne, Parkville, Victoria, Australia
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Ceulemans AG, Zgavc T, Kooijman R, Hachimi-Idrissi S, Sarre S, Michotte Y. The dual role of the neuroinflammatory response after ischemic stroke: modulatory effects of hypothermia. J Neuroinflammation 2010; 7:74. [PMID: 21040547 PMCID: PMC2988764 DOI: 10.1186/1742-2094-7-74] [Citation(s) in RCA: 229] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Accepted: 11/01/2010] [Indexed: 12/15/2022] Open
Abstract
Neuroinflammation is a key element in the ischemic cascade after cerebral ischemia that results in cell damage and death in the subacute phase. However, anti-inflammatory drugs do not improve outcome in clinical settings suggesting that the neuroinflammatory response after an ischemic stroke is not entirely detrimental. This review describes the different key players in neuroinflammation and their possible detrimental and protective effects in stroke. Because of its inhibitory influence on several pathways of the ischemic cascade, hypothermia has been introduced as a promising neuroprotective strategy. This review also discusses the influence of hypothermia on the neuroinflammatory response. We conclude that hypothermia exerts both stimulating and inhibiting effects on different aspects of neuroinflammation and hypothesize that these effects are key to neuroprotection.
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Affiliation(s)
- An-Gaëlle Ceulemans
- Department of Pharmaceutical Chemistry and Drug Analysis, Research Group Experimental Neuropharmacology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
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Neuroprotective efficacy and therapeutic window of Forsythoside B: In a rat model of cerebral ischemia and reperfusion injury. Eur J Pharmacol 2010; 640:75-81. [DOI: 10.1016/j.ejphar.2010.04.055] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2009] [Revised: 03/31/2010] [Accepted: 04/23/2010] [Indexed: 11/15/2022]
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Tu XK, Yang WZ, Wang CH, Shi SS, Zhang YL, Chen CM, Yang YK, Jin CD, Wen S. Zileuton Reduces Inflammatory Reaction and Brain Damage Following Permanent Cerebral Ischemia in Rats. Inflammation 2010; 33:344-52. [DOI: 10.1007/s10753-010-9191-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Jin R, Yang G, Li G. Inflammatory mechanisms in ischemic stroke: role of inflammatory cells. J Leukoc Biol 2010; 87:779-89. [PMID: 20130219 DOI: 10.1189/jlb.1109766] [Citation(s) in RCA: 1164] [Impact Index Per Article: 83.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Inflammation plays an important role in the pathogenesis of ischemic stroke and other forms of ischemic brain injury. Experimentally and clinically, the brain responds to ischemic injury with an acute and prolonged inflammatory process, characterized by rapid activation of resident cells (mainly microglia), production of proinflammatory mediators, and infiltration of various types of inflammatory cells (including neutrophils, different subtypes of T cells, monocyte/macrophages, and other cells) into the ischemic brain tissue. These cellular events collaboratively contribute to ischemic brain injury. Despite intense investigation, there are still numerous controversies concerning the time course of the recruitment of inflammatory cells in the brain and their pathogenic roles in ischemic brain injury. In this review, we provide an overview of the time-dependent recruitment of different inflammatory cells following focal cerebral I/R. We discuss how these cells contribute to ischemic brain injury and highlight certain recent findings and currently unanswered questions about inflammatory cells in the pathophysiology of ischemic stroke.
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Affiliation(s)
- Rong Jin
- Department of Neurosurgery, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130, USA
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96
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Hall AA, Pennypacker KR. Implications of immune system in stroke for novel therapeutic approaches. Transl Stroke Res 2010; 1:85-95. [PMID: 24323491 DOI: 10.1007/s12975-009-0003-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Revised: 10/20/2009] [Accepted: 11/09/2009] [Indexed: 12/27/2022]
Abstract
Each year, approximately 795,000 people suffer a new or recurrent stroke. About 610,000 of these are first attacks, and 185,000 are recurrent attacks. Currently, the only FDA approved treatment for ischemic stroke is the thrombolytic recombinant tissue plasminogen activator (Alteplase), which must be given within 4.5 h of stroke onset. Beyond this time, apoptotic and inflammatory processes greatly diminish the therapeutic benefits of current treatments. While there have been many experimental treatments for stroke that showed promising preclinical efficacy, these treatments have failed to show efficacy in clinical trials. In many of these cases, the preclinical animal studies did not model the clinical setting effectively. The injury that occurs following stroke is a dynamic process. To effectively treat stroke patients at clinically relevant timepoints, it is imperative to understand both the humeral and cell-mediated phenomena that occur throughout the body in response to ischemic injury over time. Promising experimental therapeutics designed to be given 1 to 2 days following stroke require both neuroprotective and anti-inflammatory properties in order to be efficacious.
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Affiliation(s)
- Aaron A Hall
- Department of Molecular Pharmacology and Physiology, School of Basic Biomedical Sciences, College of Medicine, University of South Florida, MDC Box 9, 12901, Bruce B Downs Blvd., Tampa, FL, 33612, USA
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Evolution of Inflammation and White Matter Injury in a Model of Transient Focal Ischemia. J Neuropathol Exp Neurol 2010; 69:1-15. [DOI: 10.1097/nen.0b013e3181c3ce6c] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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98
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Murikinati S, Jüttler E, Keinert T, Ridder DA, Muhammad S, Waibler Z, Ledent C, Zimmer A, Kalinke U, Schwaninger M. Activation of cannabinoid 2 receptors protects against cerebral ischemia by inhibiting neutrophil recruitment. FASEB J 2009; 24:788-98. [PMID: 19884325 DOI: 10.1096/fj.09-141275] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Activation of the cannabinoid 2 receptor (CB(2)) reduces ischemic injury in several organs. However, the mechanisms underlying this protective action are unclear. In a mouse model of ischemic stroke, we show that the CB(2) agonist JWH-133 (1 mg . kg(-1) . d(-1)) decreases the infarct size measured 3 d after onset of ischemia. The neuroprotective effect of JWH-133 was lost in CB(2)-deficient mice, confirming the specificity of JWH-133. Analysis of bone marrow chimeric mice revealed that bone marrow-derived cells mediate the CB(2) effect on ischemic brain injury. CB(2) activation reduced the number of neutrophils in the ischemic brain as shown by FACS analysis and by measuring the levels of the neutrophil marker enzyme myeloperoxidase. Indeed, we found in vitro that CB(2) activation inhibits adherence of neutrophils to brain endothelial cells. JWH-133 (1 microM) also interfered with the migration of neutrophils induced by the endogenous chemokine CXCL2 (30 ng/ml) through activation of the MAP kinase p38. This effect on neutrophils is likely responsible for the neuroprotection mediated by JWH-133 because JWH-133 was no longer protective when neutrophils were depleted. In conclusion, our data demonstrate that by activating p38 in neutrophils, CB(2) agonists inhibit neutrophil recruitment to the brain and protect against ischemic brain injury.-Murikinati, S., Jüttler, E., Keinert, T., Ridder, D. A., Muhammad, S., Waibler, Z., Ledent, C., Zimmer, A., Kalinke, U., Schwaninger, M. Activation of cannabinoid 2 receptors protects against cerebral ischemia by inhibiting neutrophil recruitment.
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Affiliation(s)
- Sasidhar Murikinati
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
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Chen H, Song YS, Chan PH. Inhibition of NADPH oxidase is neuroprotective after ischemia-reperfusion. J Cereb Blood Flow Metab 2009; 29:1262-72. [PMID: 19417757 PMCID: PMC2733333 DOI: 10.1038/jcbfm.2009.47] [Citation(s) in RCA: 236] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) is well known as a major source for superoxide radical generation in leukocytes. Superoxide radicals play a significant role in brain ischemia-reperfusion (I/R) injury. Recent data have also shown expression of NOX in the brain. However, the manner by which NOX is involved in pathologic processes after cerebral ischemia remains unknown. Therefore, we subjected mice deficient in the NOX subunit, gp91(phox) (gp91(phox)-/-), those treated with the NOX inhibitor, apocynin, and wild-type (WT) mice to 75 mins of focal ischemia followed by reperfusion. At 24 h of reperfusion, the gp91(phox)-/- and apocynin-treated mice showed 50% less brain infarction and 70% less cleaved spectrin compared with WT mice. The levels of 4-hydroxy-2-nonenal, malondialdehyde, and 8-hydroxy-2'-deoxyguanosine increased significantly after I/R, indicating oxidative brain injury. NADPH oxidase inhibition reduced biomarker generation. Furthermore, NOX was involved in postischemic inflammation in the brains, as less intercellular adhesion molecule-1 upregulation and less neutrophil infiltration were found in the NOX-inhibited mice after I/R. Moreover, gp91(phox) expression increased after ischemia, and was further aggravated by genetic copper/zinc-superoxide dismutase (SOD1) ablation, but ameliorated in SOD1-overexpressing mice. This study suggests that NOX plays a role in oxidative stress and inflammation, thus contributing to ischemic brain injury.
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Affiliation(s)
- Hai Chen
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, California 94305, USA
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Tracking the inflammatory response in stroke in vivo by sensing the enzyme myeloperoxidase. Proc Natl Acad Sci U S A 2008; 105:18584-9. [PMID: 19011099 DOI: 10.1073/pnas.0803945105] [Citation(s) in RCA: 239] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Inflammation can extend ischemic brain injury and adversely affect outcome in experimental animal models. A key difficulty in translating animal studies to humans is the lack of a definitive method to confirm and track inflammation in the brain in vivo. Myeloperoxidase (MPO), a key inflammatory enzyme secreted by activated neutrophils and macrophages/microglia, can generate highly reactive oxygen species to cause additional damage in cerebral ischemia. We report here that a functional, enzyme-activatable MRI agent can accurately track the oxidative activity of MPO noninvasively in stroke in living animals. We found that MPO is widely distributed in ischemic tissues, correlates positively with infarct size, and is detected even 3 weeks postinfarction. The peak level of MPO activity, determined by activation of the MPO-sensing agent in vivo and confirmed by MPO activity and quantitative RT-PCR assays, occurred on day 3 after ischemia. Both neutrophils and macrophages/microglia contribute to secrete MPO in the ischemic brain, although neutrophils peak earlier (days 1-3) whereas macrophages/microglia are most abundant later (days 3-7). In contrast to the conventional MRI agent diethylenetriamine-pentatacetate gadolinium, which reports blood-brain barrier disruption, MPO imaging is able to additionally track MPO activity and confirm inflammation on the molecular level in vivo, information that was previously only possible to obtain on ex vivo brain sections and impossible to assess in living human patients. Our findings could allow efficient noninvasive serial screening of therapies targeting inflammation and the use of MPO imaging as an imaging biomarker to risk-stratify patients.
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