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Xia N, Hua Y, Li J, Chen Y, Li X, Lin J, Xu H, Xie C, Wang X. 2-(2-Benzofuranyl)-2-Imidazoline Attenuates the Disruption of the Blood-Brain Barrier in EAE via NMDAR. Neurochem Res 2021; 46:1674-1685. [PMID: 33772673 DOI: 10.1007/s11064-021-03304-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 02/15/2021] [Accepted: 03/17/2021] [Indexed: 02/07/2023]
Abstract
Blood-brain barrier (BBB) disruption has been recognized as an early hallmark of multiple sclerosis (MS) pathology. Our previous studies have shown that 2-(2-Benzofuranyl)-2-imidazoline (2-BFI) protected against experimental autoimmune encephalomyelitis (EAE), a classic animal model of MS. However, the potential effects of 2-BFI on BBB permeability have not yet been evaluated in the context of EAE. Herein, we aimed to investigate the effect of 2-BFI on BBB permeability in both an animal model and an in vitro BBB model using TNF-α to imitate the inflammatory damage to the BBB in MS. In the animal model, 2-BFI reduced neurological deficits and BBB permeability in EAE mice compared with saline treatment. The Western blot results indicated that 2-BFI not only alleviated the loss of the tight junction protein occludin caused by EAE but also inhibited the activation of the NR1-ERK signaling pathway. In an in vitro BBB model, 2-BFI (100 μM) alleviated the TNF-α-induced increase in permeability and reduction in expression of occludin in monolayer bEnd.3 cells. Similar protective effects were also observed after treatment with the NMDAR antagonist MK801. The Western blot results showed that the TNF-α-induced BBB breakdown and increase in NMDAR subunit 1 (NR1) levels and ERK phosphorylation could be blocked by pretreatment with 2-BFI or MK801. However, no additional effect was observed on BBB permeability or the expression of occludin and p-ERK after pretreatment with both 2-BFI and MK801. Our study indicates that 2-BFI alleviates the disruption of BBB in the context of inflammatory injury similar to that of MS by targeting NMDAR1, as well as by likely activating the subsequent ERK signaling pathway. These results provide further evidence for 2-BFI as a potential drug for the treatment of MS.
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Affiliation(s)
- Niange Xia
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, South Baixiang, Ouhai District, Wenzhou, 325003, Zhejiang, China
| | - Yingjie Hua
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, South Baixiang, Ouhai District, Wenzhou, 325003, Zhejiang, China
| | - Jia Li
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, South Baixiang, Ouhai District, Wenzhou, 325003, Zhejiang, China
| | - Yanyan Chen
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, South Baixiang, Ouhai District, Wenzhou, 325003, Zhejiang, China
| | - Xueying Li
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, South Baixiang, Ouhai District, Wenzhou, 325003, Zhejiang, China
| | - Jiahe Lin
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, South Baixiang, Ouhai District, Wenzhou, 325003, Zhejiang, China
| | - Huiqin Xu
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, South Baixiang, Ouhai District, Wenzhou, 325003, Zhejiang, China
| | - Chenglong Xie
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, South Baixiang, Ouhai District, Wenzhou, 325003, Zhejiang, China
| | - Xinshi Wang
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, South Baixiang, Ouhai District, Wenzhou, 325003, Zhejiang, China.
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Xi H, Tao T, Zhang R, Xue X, Zhu Y, Liu J, Xin X, Zeng X. The 2-(2-benzofuranyl)-2-imidazoline provides neuroprotection against focal cerebral ischemia-reperfusion injury in diabetic rats: Influence of microglia and possible mechanisms of action. Brain Res Bull 2021; 174:230-239. [PMID: 34175385 DOI: 10.1016/j.brainresbull.2021.06.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 06/19/2021] [Accepted: 06/21/2021] [Indexed: 01/16/2023]
Abstract
Increased microglial NADPH oxidase (NOX2) production may make an important contribution to the increased incidence and severity of ischemic stroke associated with diabetes. Imidazoline receptors are closely associated with neuroprotection, but the neuroprotective effects of the selective I2-imidazoline receptor ligand 2-(2-benzofuranyl)-2-imidazoline (2BFI) in diabetes has not been established. The effect of 2BFI on microglial NOX2 production was investigated using a co-culture of neurons and microglia, and the effect on cerebral ischemia-reperfusion (IR) injury was determined in diabetic rats. Garcia neurological scores, brain infarct volumes, brain water content, TUNEL staining, blood-brain barrier, and immunofluorescent labeling for microglia were evaluated. Western blots were used to determine gp91phox and Tyr1472 expression. Anti-inflammatory cytokine (IL-10) and inflammatory cytokine secretion was determined using ELISA kits. The brain infarct volumes, TUNEL-positive neurons, expression of microglia, brain water content, blood-brain barrier structure damage, and gp91phox and Tyr1472 expression were increased, the Garcia neurological scores were significantly decreased in the IR group, and 2BFI relieved these alterations. The IL-10 concentration was increased in the IR group; 2BFI significantly improved this increase. The neuron apoptosis and necrosis rates, and production of reactive oxygen species (ROS) and inflammatory cytokines, including IL-6, IL-8, TNF-α, and 8-iso-PGF2α, were significantly increased by high glucose stimulation combined with oxygen-glucose deprivation treatment, which were inhibited by 2BFI. The 2BFI ameliorated cerebral ischemia-reperfusion injury in diabetes and decreased neuron death in an in vitro model. The mechanism underlying these findings may be related to the decreased production of inflammatory factors and reactive oxygen species from microglia.
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Affiliation(s)
- Hongjie Xi
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China.
| | - Tao Tao
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China.
| | - Ruru Zhang
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China.
| | - Xinxin Xue
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China.
| | - Yana Zhu
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China.
| | - Jiuyang Liu
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China.
| | - Xianyi Xin
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China.
| | - Xianzhang Zeng
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China.
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Wang Z, Wang L, Zhong F, Wu C, Hou ST. Early postnatal tobacco smoke exposure aggravates experimental autoimmune encephalomyelitis in adult rats. Neurochem Int 2020; 141:104892. [PMID: 33127393 DOI: 10.1016/j.neuint.2020.104892] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 10/13/2020] [Accepted: 10/23/2020] [Indexed: 12/20/2022]
Abstract
Although substantial evidence supports smoking as a risk factor for the development of multiple sclerosis (MS) in adulthood, it remains controversial whether early-life exposure to environmental tobacco smoke (ETS) increases the risk of MS later in life. Here, using experimental autoimmune encephalomyelitis (EAE) as an animal model for MS, we show that exposing neonatal rats during the first week (ETS1-EAE), but not the second week (ETS2-EAE) and the third week (ETS3-EAE) after birth, increased the severity of EAE in adulthood in comparison to pups exposed to filtered compressed air (AIR-EAE). The ETS1-EAE rats showed a worse neurological deficit score and a significant increase in CD4+ cell infiltration, demyelination, and axonal injury in the spinal cord compared to AIR-EAE, ETS2-EAE, and ETS3-EAE groups. Flow cytometry analysis showed that the ETS1 group had decreased numbers of regulatory T (Treg) cells and increased effector T (Teff) cells in the brain and spinal cord. The expressions of Treg upstream regulator Foxp3 and downstream cytokines such as IL-10 were also altered accordingly. Together, these findings demonstrate that neonatal ETS exposure suppresses Treg functions and aggravates the severity of EAE, confirming early-life exposure to ETS as a potential risk factor for multiple sclerosis in adulthood.
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Affiliation(s)
- Zhaowei Wang
- Department of Neurology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), 568 Zhonxin Bei Road, Shaoxing City, Zhejiang Province, 312000, PR China
| | - Liping Wang
- Department of Neurology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), 568 Zhonxin Bei Road, Shaoxing City, Zhejiang Province, 312000, PR China
| | - Fangfang Zhong
- Department of Neurology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), 568 Zhonxin Bei Road, Shaoxing City, Zhejiang Province, 312000, PR China
| | - Chenglong Wu
- Department of Neurology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), 568 Zhonxin Bei Road, Shaoxing City, Zhejiang Province, 312000, PR China
| | - Sheng-Tao Hou
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, 1088 Xueyuan Blvd, Nanshan District, Shenzhen, Guangdong Province, 518055, PR China; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada.
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Protective role of β-carotene against oxidative stress and neuroinflammation in a rat model of spinal cord injury. Int Immunopharmacol 2018; 61:92-99. [DOI: 10.1016/j.intimp.2018.05.022] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 05/20/2018] [Accepted: 05/23/2018] [Indexed: 12/25/2022]
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Siemian JN, Obeng S, Zhang Y, Zhang Y, Li JX. Antinociceptive Interactions between the Imidazoline I2 Receptor Agonist 2-BFI and Opioids in Rats: Role of Efficacy at the μ-Opioid Receptor. J Pharmacol Exp Ther 2016; 357:509-19. [PMID: 27056847 DOI: 10.1124/jpet.116.232421] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 04/07/2016] [Indexed: 12/14/2022] Open
Abstract
Although μ-opioids have been reported to interact favorably with imidazoline I2 receptor (I2R) ligands in animal models of chronic pain, the dependence on the μ-opioid receptor ligand efficacy on these interactions had not been previously investigated. This study systematically examined the interactions between the selective I2 receptor ligand 2-(2-benzofuranyl)-2-imidazoline hydrochloride (2-BFI) and three μ-opioid receptor ligands of varying efficacies: fentanyl (high efficacy), buprenorphine (medium-low efficacy), and 17-cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6α-[(3'-isoquinolyl) acetamido] morphine (NAQ; very low efficacy). The von Frey test of mechanical nociception and Hargreaves test of thermal nociception were used to examine the antihyperalgesic effects of drug combinations in complete Freund's adjuvant-induced inflammatory pain in rats. Food-reinforced schedule-controlled responding was used to examine the rate-suppressing effects of each drug combination. Dose-addition and isobolographical analyses were used to characterize the nature of drug-drug interactions in each assay. 2-BFI and fentanyl fully reversed both mechanical and thermal nociception, whereas buprenorphine significantly reversed thermal but only slightly reversed mechanical nociception. NAQ was ineffective in both nociception assays. When studied in combination with fentanyl, NAQ acted as a competitive antagonist (apparent pA2 value: 6.19). 2-BFI/fentanyl mixtures produced additive to infra-additive analgesic interactions, 2-BFI/buprenorphine mixtures produced supra-additive to infra-additive interactions, and 2-BFI/NAQ mixtures produced supra-additive to additive interactions in the nociception assays. The effects of all combinations on schedule-controlled responding were generally additive. Results consistent with these were found in experiments using female rats. These findings indicate that lower-efficacy μ-opioid receptor agonists may interact more favorably with I2R ligands than high-efficacy μ-opioid receptor agonists.
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Affiliation(s)
- Justin N Siemian
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York (J.N.S., J.-X.L.); Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia (S.O., Yan.Z.); and Research Triangle Institute, Research Triangle Park, North Carolina (Yanan.Z.)
| | - Samuel Obeng
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York (J.N.S., J.-X.L.); Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia (S.O., Yan.Z.); and Research Triangle Institute, Research Triangle Park, North Carolina (Yanan.Z.)
| | - Yan Zhang
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York (J.N.S., J.-X.L.); Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia (S.O., Yan.Z.); and Research Triangle Institute, Research Triangle Park, North Carolina (Yanan.Z.)
| | - Yanan Zhang
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York (J.N.S., J.-X.L.); Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia (S.O., Yan.Z.); and Research Triangle Institute, Research Triangle Park, North Carolina (Yanan.Z.)
| | - Jun-Xu Li
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York (J.N.S., J.-X.L.); Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia (S.O., Yan.Z.); and Research Triangle Institute, Research Triangle Park, North Carolina (Yanan.Z.)
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Thorne N, Malik N, Shah S, Zhao J, Class B, Aguisanda F, Southall N, Xia M, McKew JC, Rao M, Zheng W. High-Throughput Phenotypic Screening of Human Astrocytes to Identify Compounds That Protect Against Oxidative Stress. Stem Cells Transl Med 2016; 5:613-27. [PMID: 27034412 PMCID: PMC4835244 DOI: 10.5966/sctm.2015-0170] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 01/14/2016] [Indexed: 01/17/2023] Open
Abstract
UNLABELLED Astrocytes are the predominant cell type in the nervous system and play a significant role in maintaining neuronal health and homeostasis. Recently, astrocyte dysfunction has been implicated in the pathogenesis of many neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. Astrocytes are thus an attractive new target for drug discovery for neurological disorders. Using astrocytes differentiated from human embryonic stem cells, we have developed an assay to identify compounds that protect against oxidative stress, a condition associated with many neurodegenerative diseases. This phenotypic oxidative stress assay has been optimized for high-throughput screening in a 1,536-well plate format. From a screen of approximately 4,100 bioactive tool compounds and approved drugs, we identified a set of 22 that acutely protect human astrocytes from the consequences of hydrogen peroxide-induced oxidative stress. Nine of these compounds were also found to be protective of induced pluripotent stem cell-differentiated astrocytes in a related assay. These compounds are thought to confer protection through hormesis, activating stress-response pathways and preconditioning astrocytes to handle subsequent exposure to hydrogen peroxide. In fact, four of these compounds were found to activate the antioxidant response element/nuclear factor-E2-related factor 2 pathway, a protective pathway induced by toxic insults. Our results demonstrate the relevancy and utility of using astrocytes differentiated from human stem cells as a disease model for drug discovery and development. SIGNIFICANCE Astrocytes play a key role in neurological diseases. Drug discovery efforts that target astrocytes can identify novel therapeutics. Human astrocytes are difficult to obtain and thus are challenging to use for high-throughput screening, which requires large numbers of cells. Using human embryonic stem cell-derived astrocytes and an optimized astrocyte differentiation protocol, it was possible to screen approximately 4,100 compounds in titration to identify 22 that are cytoprotective of astrocytes. This study is the largest-scale high-throughput screen conducted using human astrocytes, with a total of 17,536 data points collected in the primary screen. The results demonstrate the relevancy and utility of using astrocytes differentiated from human stem cells as a disease model for drug discovery and development.
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Affiliation(s)
- Natasha Thorne
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, USA
| | - Nasir Malik
- Laboratory of Stem Cell Biology, National Institute of Arthritis, Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Sonia Shah
- Laboratory of Stem Cell Biology, National Institute of Arthritis, Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jean Zhao
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, USA
| | - Bradley Class
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, USA
| | - Francis Aguisanda
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, USA
| | - Noel Southall
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, USA
| | - Menghang Xia
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, USA
| | - John C McKew
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, USA
| | - Mahendra Rao
- NIH Center for Regenerative Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Wei Zheng
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, USA
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Brain Protection Conferred by Long-Term Administration of 2-(2-Benzofuranyl)-2-Imidazoline Against Experimental Autoimmune Encephalomyelitis. Neurochem Res 2014; 40:572-8. [DOI: 10.1007/s11064-014-1502-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 12/06/2014] [Accepted: 12/11/2014] [Indexed: 11/26/2022]
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Xu H, Ou F, Wang P, Naren M, Tu D, Zheng R. High dosage of agmatine alleviates pentylenetetrazole-induced chronic seizures in rats possibly by exerting an anticonvulsive effect. Exp Ther Med 2014; 8:73-78. [PMID: 24944600 PMCID: PMC4061208 DOI: 10.3892/etm.2014.1711] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 03/27/2014] [Indexed: 01/16/2023] Open
Abstract
The aim of the present study was to investigate the mechanism underlying the effects of different doses of agmatine in rats with chronic epilepsy. To generate chronic epilepsy models, rats pretreated with different doses of agmatine (20, 40 and 80 mg/kg) were intraperitoneally injected with pentylenetetrazole (35 mg/kg) for 28 consecutive days. Epileptic behavior was observed using behavioral measurements of convulsion for 1 h after each treatment with pentylenetetrazole. Morphological alterations of the hippocampal neurons were also observed using hematoxylin and eosin staining. In addition, the expression levels of glial fibrillary acidic protein and inducible nitric oxide synthase (iNOS) in the hippocampus were detected by immunohistochemistry. Furthermore, reverse transcription polymerase chain reaction was performed to detect the mRNA expression of two subunits (NR1 and NR2B) of the N-methyl-D-aspartic acid (NMDA) receptor in the rat hippocampus. The results demonstrated that administration of agmatine (80 mg/kg) significantly decreased the daily average grade of epileptic seizures and also reduced neuronal loss and astrocyte hyperplasia in the hippocampal area. Furthermore, agmatine (80 mg/kg) affected the mRNA expression levels of the NR1 subunit of the NMDA receptor, however, agmatine had no effect on the expression of iNOS in the hippocampus. Higher doses of agmatine inhibited the effect of pentylenetetrazole in rats, reduced astrocytic hyperplasia and neuronal damage in the hippocampus caused by seizures and selectively reduced the expression of the NR1 subunit of NMDA. Our results suggest that agmatine has an anticonvulsive effect in chronic epilepsy.
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Affiliation(s)
- Huiqin Xu
- Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, Wenzhou, Zhejiang 325000, P.R. China
| | - Fuyong Ou
- Department of Neurology, Chenzhou No. 1 People's Hospital, Chenzhou, Hunan 423000, P.R. China
| | - Pei Wang
- Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, Wenzhou, Zhejiang 325000, P.R. China
| | - Mangdula Naren
- Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, Wenzhou, Zhejiang 325000, P.R. China
| | - Dongpei Tu
- Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, Wenzhou, Zhejiang 325000, P.R. China
| | - Rongyuan Zheng
- Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, Wenzhou, Zhejiang 325000, P.R. China
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Idazoxan reduces blood-brain barrier damage during experimental autoimmune encephalomyelitis in mouse. Eur J Pharmacol 2014; 736:70-6. [PMID: 24797785 DOI: 10.1016/j.ejphar.2014.04.034] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 04/22/2014] [Accepted: 04/23/2014] [Indexed: 11/21/2022]
Abstract
We have previously shown that Idazoxan (IDA), an imidazoline 2 receptor ligand, is neuroprotective against spinal cord injury caused by experimental autoimmune encephalomyelitis (EAE) in mouse, an animal modal of multiple sclerosis (MS). However, the protective mechanism remains unclear. Here, we provided evidence to show that IDA confers neuroprotection through reduction in blood-brain barrier (BBB) damage. EAE was induced by immunizing C57 BL/6 mice with myelin oligodendrocyte glycoprotein35-55 amino acid peptide (MOG35-55). IDA was administrated for 14 days after MOG immunization at 2 mg/kg (i.p., bid). Significant reduction in BBB damage occurred in the IDA-treated group of mice compared with the saline-treated group, as evidenced by the reduction in Evan׳s blue content in the brain tissue and the reduced BBB tight junction damage viewed under a transmission electron microscope. Moreover, EAE-induced reductions in tight junction proteins (JAM-1, Occludin, Claudin-5 and ZO-1) were also significantly ameliorated in IDA-treated mice, all of which supported the notion that IDA reduced BBB damage. Interestingly, the expression levels of extracellular matrix metalloproteinase-9 (MMP-9) and the ratio of MMP-9 against tissue inhibitor of metalloproteinase-1 (TIMP-1), which is known to be associated with MS-induced BBB damage, were significantly reduced in IDA-treated group, lending further support to the hypothesis that IDA confers brain protection through reducing BBB damage. This study raised a possibility that IDA is a promising pro-drug for development against MS.
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Pazhoohan S, Satarian L, Asghari AA, Salimi M, Kiani S, Mani AR, Javan M. Valproic Acid attenuates disease symptoms and increases endogenous myelin repair by recruiting neural stem cells and oligodendrocyte progenitors in experimental autoimmune encephalomyelitis. NEURODEGENER DIS 2013; 13:45-52. [PMID: 23949302 DOI: 10.1159/000352021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Accepted: 05/14/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND inefficient remyelination of demyelinated plaques in multiple sclerosis (ms) leads to secondary axon degeneration and progressive disability. therapies that potentiate remyelination would be of immense help for managing MS. OBJECTIVE Here, we report the effects of valproic acid (VPA) on focal experimental autoimmune encephalomyelitis (fEAE). METHODS fEAE was induced in Wistar rats by immunizing the animals with guinea pig spinal cord homogenate emulsified in complete Freund's adjuvant and with pertussis toxin (PT) injection into the spinal cord at the level of T8 vertebra on day 18 after immunization. VPA 300 mg/kg was applied for 4 days after or 8 days before PT administration. Behavioral evaluation, histological assessment and immunohistofluorescence assays were used to evaluate the outcomes. RESULTS VPA administration had no effect on the development of symptoms, but after discontinuing VPA, animals showed faster recovery. Eight days of pretreatment with VPA accelerated the recovery phase of EAE and increased the number of remyelinated axons in the lesion area. VPA pretreatment also increased the recruitment of neural stem cells and oligodendrocyte precursors within the lesion. CONCLUSIONS Results suggest VPA as a potential therapy for remyelinating the lesions in MS and for faster recovery from disease relapses. The effect of VPA seems to be mediated by endogenous progenitors recruitment.
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Affiliation(s)
- Saeed Pazhoohan
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
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Han Z, Yang JL, Jiang SX, Hou ST, Zheng RY. Fast, non-competitive and reversible inhibition of NMDA-activated currents by 2-BFI confers neuroprotection. PLoS One 2013; 8:e64894. [PMID: 23741413 PMCID: PMC3669129 DOI: 10.1371/journal.pone.0064894] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 04/18/2013] [Indexed: 11/18/2022] Open
Abstract
Excessive activation of the N-methyl-D-aspartic acid (NMDA) type glutamate receptors (NMDARs) causes excitotoxicity, a process important in stroke-induced neuronal death. Drugs that inhibit NMDA receptor-mediated [Ca(2+)]i influx are potential leads for development to treat excitotoxicity-induced brain damage. Our previous studies showed that 2-(2-benzofu-ranyl)-2-imidazoline (2-BFI), an immidazoline receptor ligand, dose-dependently protects rodent brains from cerebral ischemia injury. However, the molecular mechanisms remain unclear. In this study, we found that 2-BFI transiently and reversibly inhibits NMDA, but not AMPA currents, in a dose-dependent manner in cultured rat cortical neurons. The mechanism of 2-BFI inhibition of NMDAR is through a noncompetitive fashion with a faster on (Kon = 2.19±0.33×10(-9) M(-1) sec(-1)) and off rate (Koff = 0.67±0.02 sec(-1)) than those of memantine, a gold standard for therapeutic inhibition NMDAR-induced excitotoxicity. 2-BFI also transiently and reversibly blocked NMDA receptor-mediated calcium entry to cultured neurons and provided long-term neuroprotection against NMDA toxicity in vitro. Collectively, these studies demonstrated a potential mechanism of 2-BFI-mediated neuroprotection and indicated that 2-BFI is an excellent candidate for repositioning as a drug for stroke treatment.
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Affiliation(s)
- Zhao Han
- Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, Wenzhou, Zhejiang Province, P. R. China
| | - Jin-Long Yang
- Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, Wenzhou, Zhejiang Province, P. R. China
| | - Susan X. Jiang
- Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
| | - Sheng-Tao Hou
- Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
- * E-mail: (STH); (RYZ)
| | - Rong-Yuan Zheng
- Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, Wenzhou, Zhejiang Province, P. R. China
- * E-mail: (STH); (RYZ)
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Li F, Zhang ZX, Liu YF, Xu HQ, Hou ST, Zheng RY. 2-BFI ameliorates EAE-induced mouse spinal cord damage: Effective therapeutic time window and possible mechanisms. Brain Res 2012; 1483:13-9. [DOI: 10.1016/j.brainres.2012.09.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 09/02/2012] [Accepted: 09/10/2012] [Indexed: 10/27/2022]
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13
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Yao SQ, Li ZZ, Huang QY, Li F, Wang ZW, Augusto E, He JC, Wang XT, Chen JF, Zheng RY. Genetic inactivation of the adenosine A2Areceptor exacerbates brain damage in mice with experimental autoimmune encephalomyelitis. J Neurochem 2012; 123:100-12. [DOI: 10.1111/j.1471-4159.2012.07807.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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14
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Han Z, Cheng ZH, Liu S, Yang JL, Xiao MJ, Zheng RY, Hou ST. Neurovascular protection conferred by 2-BFI treatment during rat cerebral ischemia. Biochem Biophys Res Commun 2012; 424:544-8. [PMID: 22771326 DOI: 10.1016/j.bbrc.2012.06.152] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 06/28/2012] [Indexed: 11/19/2022]
Abstract
Stroke is caused by vascular dysfunction and currently there are no effective therapeutics to stroke induced brain damage. In contrast to an intense emphasis on neuroprotection, relatively few studies have addressed means of vascular protection in cerebral ischemia. Here we discovered that the ligand to immidazolin receptor, 2-BFI, not only provided potent neuroprotection during middle cerebral artery occlusion in rat, which confirmed our previous reports, but also protected the integrity of the cerebral vasculature. Treatment with 2-BFI twice daily after the occlusion of the middle cerebral artery for 14 d significantly improved the neurological deficits, reduced brain infarction, and importantly, protected the cerebral vasculature as evidenced by the increased expression of an endothelial marker, von Willebrand factor, and better preservation of the cerebral vasculature, as viewed under a confocal microscope on rat brain perfused with FITC-labeled dextran. These results indicated that 2-BFI contributes to protection of neurovasculature. Understanding the molecular mechanisms could eventually lead to development of more effective therapies for stroke.
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Affiliation(s)
- Zhao Han
- Division of Stroke Medicine, Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, No. 2 Fuxue Lane, Wenzhou City, Zhejiang Province 325000, PR China.
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15
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Mackinnon SE, Yee A, Ray WZ. Nerve transfers for the restoration of hand function after spinal cord injury. J Neurosurg 2012; 117:176-85. [DOI: 10.3171/2012.3.jns12328] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Spinal cord injury (SCI) remains a significant public health problem. Despite advances in understanding of the pathophysiological processes of acute and chronic SCI, corresponding advances in translational applications have lagged behind. Nerve transfers using an expendable nearby motor nerve to reinnervate a denervated nerve have resulted in more rapid and improved functional recovery than traditional nerve graft reconstructions following a peripheral nerve injury. The authors present a single case of restoration of some hand function following a complete cervical SCI utilizing nerve transfers.
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Affiliation(s)
| | - Andrew Yee
- 1Division of Plastic and Reconstructive Surgery, and
| | - Wilson Z. Ray
- 2Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri
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16
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C3-dependent mechanism of microglial priming relevant to multiple sclerosis. Proc Natl Acad Sci U S A 2012; 109:965-70. [PMID: 22219359 DOI: 10.1073/pnas.1111924109] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Microglial priming predisposes the brain to neurodegeneration and affects disease progression. The signal to switch from the quiescent to the primed state is unknown. We show that deleting the C3 convertase regulator complement receptor 1-related protein y (Crry) induces microglial priming. Mice that were double-knockout for Crry and either C3 or factor B did not show priming, demonstrating dependence on alternative pathway activation. Colocalization of C3b/iC3b and CR3 implicated the CR3/iC3b interaction in priming. Systemic lipopolysaccharide challenge overactivated primed microglia with florid expression of proinflammatory molecules, which were blocked by complement inhibition. Relevance for neurodegenerative disease is exemplified by human multiple sclerosis (MS) and by experimental autoimmune encephalomyelitis (EAE), a model of MS. In human MS, microglial priming was evident in perilesional white matter, in close proximity to C3b/iC3b deposits. EAE was accelerated and exacerbated in Crry-deficient mice, and was dependent on C activation. In summary, C3-dependent microglial priming confers susceptibility to other challenges. Our observations are relevant to progression in MS and other neurological diseases exacerbated by acute insults.
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Early-life exposure to lipopolysaccharide reduces the severity of experimental autoimmune encephalomyelitis in adulthood and correlated with increased urine corticosterone and apoptotic CD4+ T cells. Neuroscience 2011; 193:283-90. [DOI: 10.1016/j.neuroscience.2011.07.047] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2011] [Revised: 07/10/2011] [Accepted: 07/13/2011] [Indexed: 11/18/2022]
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18
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Wang P, Wang ZW, Lin FH, Han Z, Hou ST, Zheng RY. 2-BFI attenuates experimental autoimmune encephalomyelitis-induced spinal cord injury with enhanced B-CK, CaATPase, but reduced calpain activity. Biochem Biophys Res Commun 2011; 406:152-7. [DOI: 10.1016/j.bbrc.2011.02.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 02/02/2011] [Indexed: 12/28/2022]
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19
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Li XL, Lv J, Xi NN, Wang T, Shang XF, Xu HQ, Han Z, O'Byrne KT, Li XF, Zheng RY. Neonatal endotoxin exposure suppresses experimental autoimmune encephalomyelitis through regulating the immune cells responsivity in the central nervous system of adult rats. Biochem Biophys Res Commun 2010; 398:302-8. [PMID: 20599716 DOI: 10.1016/j.bbrc.2010.06.086] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Accepted: 06/21/2010] [Indexed: 01/06/2023]
Abstract
Early-life exposure to bacterial endotoxin (lipopolysaccharide, LPS) affects the susceptibility to a variety of systemic organic inflammation in adulthood. To determine the long-term effects of neonatal LPS exposure on inflammatory responses in the central nervous system (CNS) in adulthood, we examined the effects on the development of experimental autoimmune encephalomyelitis (EAE) in adult rats as well as the potential regulatory immune mechanisms involved. The results showed that neonatal LPS exposure significantly reduced the morbidity (p<0.01) and severity (p<0.05) of EAE in adult rats, and decreased inflammatory cell infiltration and demyelination in the CNS compared with neonatal saline controls (p<0.05). Neonatal LPS-treated animals showed reduced activation of microglia and astrocytes, as detected by immunocytochemistry, accompanied by down-regulation of the pro-inflammatory cytokines interleukin-17 and interferon-gamma but up-regulation of anti-inflammatory cytokine interleukin-10 in the CNS (p<0.05). At the same time, cerebrum mRNA levels of the transcription factors T-bet and RORgammat were lower in neonatal LPS-compared with saline- treated animals (p<0.05) accompanied with increased STAT-6 and Foxp3 levels in the neonatal LPS-treated group (p<0.05). These findings suggest that early-life exposure to LPS could provide an important neuroprotective effect on the development of EAE in adult rats due to modulation of inflammatory responses in the CNS.
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Affiliation(s)
- Xiao-Li Li
- Department of Neurology, The First Affiliated Hospital and Research Institute of Experimental Neurobiology, Wenzhou Medical College, No. 2 Fuxue Lane, Wenzhou City, 325000 Zhejiang, PR China
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Chronic caffeine treatment attenuates experimental autoimmune encephalomyelitis induced by guinea pig spinal cord homogenates in Wistar rats. Brain Res 2010; 1309:116-25. [DOI: 10.1016/j.brainres.2009.10.054] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Revised: 10/16/2009] [Accepted: 10/22/2009] [Indexed: 11/20/2022]
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