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Shen G, Xiao H, Huang S, Yuan X, Rongrong Z, Ma Y, Qin X. Knockdown of repulsive guidance molecule a promotes polarization of microglia into an anti-inflammatory phenotype after oxygen-glucose deprivation-reoxygenation in vitro. Neurochem Int 2023; 170:105546. [PMID: 37169181 DOI: 10.1016/j.neuint.2023.105546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 04/09/2023] [Accepted: 05/08/2023] [Indexed: 05/13/2023]
Abstract
Repulsive guidance molecule a (RGMa) is a glycosylphosphatidylinositol-anchored glycoprotein that has been demonstrated to influence neuroinflammatory-related diseases in addition to regulating neuronal differentiation and survival during brain development. However, any function or mechanism of RGMa in the polarization of microglia after ischemic stroke remains unclear. In the current study, RGMa was found to be expressed at reduced levels in microglia after oxygen-glucose deprivation-reoxygenation (OGD/R) in vitro. RGMa overexpression induced HAPI microglia to predominantly polarize to the M1 phenotype, promoting the release of proinflammatory cytokines and knockdown induced the M2 phenotype, promoting the release of anti-inflammatory cytokines. RGMa overexpression also regulated the polarization of HAPI microglia by inhibiting the transportation of peroxisome proliferator-activated receptor γ (PPARγ) from the nucleus to cytoplasm. The opposite effect resulted from RGMa-knockdown and was reversed by the PPARγ antagonist, GW9662. In addition, RGMa-knockdown HAPI microglial conditioned medium improved the survival of oligodendrocytes after OGD/R in vitro. Thus, inhibition of RGMa may constitute a therapeutic strategy for reducing neuroinflammation after ischemic stroke.
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Affiliation(s)
- Guanru Shen
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Hongmei Xiao
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Siyuan Huang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Xiaofan Yuan
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Zhang Rongrong
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Yue Ma
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Xinyue Qin
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China.
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Kalluri HV, Rosebraugh MR, Misko TP, Ziemann A, Liu W, Cree BAC. Phase 1 Evaluation of Elezanumab (Anti-Repulsive Guidance Molecule A Monoclonal Antibody) in Healthy and Multiple Sclerosis Participants. Ann Neurol 2023; 93:285-296. [PMID: 36093738 PMCID: PMC10100020 DOI: 10.1002/ana.26503] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 08/01/2022] [Accepted: 09/06/2022] [Indexed: 01/31/2023]
Abstract
OBJECTIVE This study was undertaken to describe the safety, tolerability, pharmacokinetics, and immunogenicity of elezanumab (ABT-555), a fully human monoclonal antibody (mAb) directed against repulsive guidance molecule A (RGMa), in healthy and multiple sclerosis (MS) study participants. METHODS The single-center, first-in-human, single ascending dose (SAD) study evaluated elezanumab (50-1,600mg intravenous [IV] and 150mg subcutaneous) in 47 healthy men and women. The multicenter multiple ascending dose (MAD; NCT02601885) study evaluated elezanumab (150mg, 600mg, and 1,800mg) in 20 adult men and women with MS, receiving either maintenance or no immunomodulatory treatment. RESULTS No pattern of study drug-related adverse events was identified for either the SAD or MAD elezanumab regimens. Across both studies, the Tmax occurred within 4 hours of elezanumab IV infusion, and the harmonic mean of t1/2 ranged between 18.6 and 67.7 days. Following multiple dosing, elezanumab Cmax , area under the curve, and Ctrough increased dose-proportionally and resulted in dose-dependent increases in elezanumab cerebrospinal fluid (CSF) concentrations. Elezanumab CSF penetration was 0.1% to 0.4% across both studies, with CSF levels of free RGMa decreased by >40%. Changes in CSF interleukin-10 (IL-10) and free RGMa demonstrated dose/exposure-dependence. INTERPRETATION The elezanumab pharmacokinetic profile supports monthly, or bimonthly, administration of up to 1,800mg with the option of a loading dose of 3,600mg. Elezanumab partitioning into CSF is within the range expected for mAbs. Reduced CSF levels of free RGMa demonstrate central nervous system target binding of elezanumab with an apparent maximal effect at 1,800mg IV. Exposure-associated increases in CSF IL-10, an anti-inflammatory cytokine with neuroprotective/neurorestorative properties, support potential pathway modulation in MS participants. ANN NEUROL 2023;93:285-296.
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Affiliation(s)
- Hari V Kalluri
- Clinical Pharmacology and Pharmacometrics, AbbVie, North Chicago, IL
| | | | | | | | - Wei Liu
- Clinical Pharmacology and Pharmacometrics, AbbVie, North Chicago, IL
| | - Bruce A C Cree
- Weill Institute of Neurosciences, Department of Neurology, University of California, San Francisco, San Francisco, CA
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3
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Parray A, Akhtar N, Pir GJ, Pananchikkal SV, Ayadathil R, Mir FA, Francis R, Own A, Shuaib A. Increase in repulsive guidance molecule-a (RGMa) in lacunar and cortical stroke patients is related to the severity of the insult. Sci Rep 2022; 12:20788. [PMID: 36456640 PMCID: PMC9715939 DOI: 10.1038/s41598-022-24481-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 11/16/2022] [Indexed: 12/03/2022] Open
Abstract
Repulsive guidance molecule-a (RGMa) inhibits angiogenesis and increases inflammation. Animal models of cerebral ischemia have shown that an increased expression of RGMa leads to larger infarction and its inhibition attenuates effects of ischemia. We report on the relationship of RGMa to stroke types and severity. This is a prospective study in patients admitted to the stroke service in Qatar. We collected the clinical determinants, including NIHSS at admission, imaging and outcome at discharge and 90-days. RGMa levels were determined by measuring mRNA levels extracted from peripheral blood mononuclear cells (PBMCs) within 24 h of onset and at 5 days. There were 90 patients (lacunar: 64, cortical: 26) and 35 age-matched controls. RGMa mRNA levels were significantly higher in the stroke patients: day 1: 1.007 ± 0.13 versus 2.152 ± 0.19 [p < 0.001] and day-5: 3.939 ± 0.36 [p < 0.0001]) and significantly higher in patients with severe stroke (NIHSS ≥ 8) compared to milder symptoms (NIHSS < 8) at day 1 (NIHSS ≥ 8: 2.563 ± 0.36; NIHSS < 8: 1.947 ± 0.2) and day 5 (NIHSS ≥ 8: 5.25 ± 0.62; NIHSS < 8: 3.259 ± 0.419). Cortical stroke patients had marginally higher RGMa mRNA levels compared to lacunar stroke at day 1 (cortical stroke: 2.621 ± 0.46 vs lacunar stroke: 1.961 ± 0.19) and day 5 (cortical stroke: 4.295 ± 0.76 vs lacunar stroke: 3.774 ± 0.39). In conclusion, there is an increase in the level of RGMa mRNA in patients with acute stroke and seen in patients with lacunar and cortical stroke. The increase in RGMa mRNA levels is related to the severity of the stroke and increases over the initial 5 days. Further studies are required to determine the effects of the increase in RGMa on stroke recovery.
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Affiliation(s)
- Aijaz Parray
- grid.413548.f0000 0004 0571 546XThe Neuroscience Institute, Academic Health System, Hamad Medical Corporation, 3050 Doha, Qatar
| | - Naveed Akhtar
- grid.413548.f0000 0004 0571 546XThe Neuroscience Institute, Academic Health System, Hamad Medical Corporation, 3050 Doha, Qatar
| | - Ghulam Jeelani Pir
- grid.413548.f0000 0004 0571 546XThe Neuroscience Institute, Academic Health System, Hamad Medical Corporation, 3050 Doha, Qatar
| | - Sajitha V. Pananchikkal
- grid.413548.f0000 0004 0571 546XThe Neuroscience Institute, Academic Health System, Hamad Medical Corporation, 3050 Doha, Qatar
| | - Raheem Ayadathil
- grid.413548.f0000 0004 0571 546XThe Neuroscience Institute, Academic Health System, Hamad Medical Corporation, 3050 Doha, Qatar
| | - Fayaz Ahmad Mir
- grid.413548.f0000 0004 0571 546XQatar Metabolic Institute, Academic Health System, Hamad Medical Corporation, 3050 Doha, Qatar
| | - Reny Francis
- grid.413548.f0000 0004 0571 546XThe Neuroscience Institute, Academic Health System, Hamad Medical Corporation, 3050 Doha, Qatar
| | - Ahmed Own
- grid.413548.f0000 0004 0571 546XThe Neuroscience Institute, Academic Health System, Hamad Medical Corporation, 3050 Doha, Qatar
| | - Ashfaq Shuaib
- grid.17089.370000 0001 2190 316XDivision of Neurology, Faculty of Medicine, University of Alberta, Edmonton, T6G 2G3 Canada
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4
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Liu D, Zusman BE, Shaffer JR, Li Y, Arockiaraj AI, Liu S, Weeks DE, Desai SM, Kochanek PM, Puccio AM, Okonkwo DO, Conley YP, Jha RM. Decreased DNA Methylation of RGMA is Associated with Intracranial Hypertension After Severe Traumatic Brain Injury: An Exploratory Epigenome-Wide Association Study. Neurocrit Care 2022; 37:26-37. [PMID: 35028889 PMCID: PMC9287123 DOI: 10.1007/s12028-021-01424-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 12/14/2021] [Indexed: 01/01/2023]
Abstract
BACKGROUND Cerebral edema and intracranial hypertension are major contributors to unfavorable prognosis in traumatic brain injury (TBI). Local epigenetic changes, particularly in DNA methylation, may influence gene expression and thus host response/secondary injury after TBI. It remains unknown whether DNA methylation in the central nervous system is associated with cerebral edema severity or intracranial hypertension post TBI. We sought to identify epigenome-wide DNA methylation patterns associated with these forms of secondary injury after TBI. METHODS We obtained genome-wide DNA methylation profiles of DNA extracted from ventricular cerebrospinal fluid samples at three different postinjury time points from a prospective cohort of patients with severe TBI (n = 89 patients, 254 samples). Cerebral edema and intracranial pressure (ICP) measures were clustered to generate composite end points of cerebral edema and ICP severity. We performed an unbiased epigenome-wide association study (EWAS) to test associations between DNA methylation at 419,895 cytosine-phosphate-guanine (CpG) sites and cerebral edema/ICP severity categories. Given inflated p values, we conducted permutation tests for top CpG sites to filter out potential false discoveries. RESULTS Our data-driven hierarchical clustering across six cerebral edema and ICP measures identified two groups differing significantly in ICP based on the EWAS-identified CpG site cg22111818 in RGMA (Repulsive guidance molecule A, permutation p = 4.20 × 10-8). At 3-4 days post TBI, patients with severe intracranial hypertension had significantly lower levels of methylation at cg22111818. CONCLUSIONS We report a novel potential relationship between intracranial hypertension after TBI and an acute, nonsustained reduction in DNA methylation at cg22111818 in the RGMA gene. To our knowledge, this is the largest EWAS in severe TBI. Our findings are further strengthened by previous findings that RGMA modulates axonal repair in other central nervous system disorders, but a role in intracranial hypertension or TBI has not been previously identified. Additional work is warranted to validate and extend these findings, including assessment of its possible role in risk stratification, identification of novel druggable targets, and ultimately our ability to personalize therapy in TBI.
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Affiliation(s)
- Dongjing Liu
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Ave, New York, NY, 10029, USA
| | - Benjamin E Zusman
- School of Medicine, University of Pittsburgh, 3550 Terrace St, Pittsburgh, PA, 15213, USA
| | - John R Shaffer
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 De Soto St, Pittsburgh, PA, 15261, USA
- Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, 3501 Terrace St, Pittsburgh, PA, 15213, USA
| | - Yunqi Li
- Institute for Public Health Genetics, School of Public Health, University of Washington, 1959 NE Pacific St, Seattle, WA, 98195, USA
| | - Annie I Arockiaraj
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 De Soto St, Pittsburgh, PA, 15261, USA
| | - Shuwei Liu
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 De Soto St, Pittsburgh, PA, 15261, USA
| | - Daniel E Weeks
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 De Soto St, Pittsburgh, PA, 15261, USA
- Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, 130 De Soto St, Pittsburgh, PA, 15261, USA
| | - Shashvat M Desai
- Department of Neurology, Neurobiology and Neurosurgery, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, 240 West Thomas Road, Phoenix, AZ, 85013, USA
| | - Patrick M Kochanek
- Safar Center for Resuscitation Research, John G Rangos Research Center, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, 15224, USA
| | - Ava M Puccio
- Department of Neurological Surgery, School of Medicine, University of Pittsburgh, 200 Lothrop Street, Suite B-400, Pittsburgh, PA, 15213, USA
| | - David O Okonkwo
- School of Nursing, University of Pittsburgh, 200 Lothrop Street, Suite B-400, Pittsburgh, PA, 15261, USA
| | - Yvette P Conley
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, 130 De Soto St, Pittsburgh, PA, 15261, USA.
- School of Nursing, University of Pittsburgh, 200 Lothrop Street, Suite B-400, Pittsburgh, PA, 15261, USA.
| | - Ruchira M Jha
- Department of Neurology, Neurobiology and Neurosurgery, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, 240 West Thomas Road, Phoenix, AZ, 85013, USA.
- Department of Neurobiology, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, 240 West Thomas Road, Phoenix, AZ, 85013, USA.
- Department of Neurosurgery, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, 240 West Thomas Road, Phoenix, AZ, 85013, USA.
- St Joseph's Hospital and Medical Center, 240 W Thomas Rd, Phoenix, AZ, 85013, USA.
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Torres-Querol C, Quintana-Luque M, Arque G, Purroy F. Preclinical evidence of remote ischemic conditioning in ischemic stroke, a metanalysis update. Sci Rep 2021; 11:23706. [PMID: 34887465 PMCID: PMC8660795 DOI: 10.1038/s41598-021-03003-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 11/12/2021] [Indexed: 01/13/2023] Open
Abstract
Remote ischemic conditioning (RIC) is a promising therapeutic approach for ischemic stroke patients. It has been proven that RIC reduces infarct size and improves functional outcomes. RIC can be applied either before ischemia (pre-conditioning; RIPreC), during ischemia (per-conditioning; RIPerC) or after ischemia (post-conditioning; RIPostC). Our aim was to systematically determine the efficacy of RIC in reducing infarct volumes and define the cellular pathways involved in preclinical animal models of ischemic stroke. A systematic search in three databases yielded 50 peer-review articles. Data were analyzed using random effects models and results expressed as percentage of reduction in infarct size (95% CI). A meta-regression was also performed to evaluate the effects of covariates on the pooled effect-size. 95.3% of analyzed experiments were carried out in rodents. Thirty-nine out of the 64 experiments studied RIPostC (61%), sixteen examined RIPreC (25%) and nine tested RIPerC (14%). In all studies, RIC was shown to reduce infarct volume (- 38.36%; CI - 42.09 to - 34.62%) when compared to controls. There was a significant interaction caused by species. Short cycles in mice significantly reduces infarct volume while in rats the opposite occurs. RIPreC was shown to be the most effective strategy in mice. The present meta-analysis suggests that RIC is more efficient in transient ischemia, using a smaller number of RIC cycles, applying larger length of limb occlusion, and employing barbiturates anesthetics. There is a preclinical evidence for RIC, it is safe and effective. However, the exact cellular pathways and underlying mechanisms are still not fully determined, and its definition will be crucial for the understanding of RIC mechanism of action.
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Affiliation(s)
- Coral Torres-Querol
- Clinical Neurosciences Group, Institut de Recerca Biomèdica de Lleida (IRBLleida), Lleida, Spain
| | - Manuel Quintana-Luque
- Epilepsy Unit, Neurology Department, Vall d'Hebron University Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Gloria Arque
- Clinical Neurosciences Group, Institut de Recerca Biomèdica de Lleida (IRBLleida), Lleida, Spain
- Experimental Medicine Department, Universitat de Lleida, Lleida, Spain
| | - Francisco Purroy
- Clinical Neurosciences Group, Institut de Recerca Biomèdica de Lleida (IRBLleida), Lleida, Spain.
- Medicine Department, Universitat de Lleida, Institut de Recerca Biomèdica de Lleida (IRBLleida), Lleida, Spain.
- Stroke Unit, Department of Neurology, Universitat de Lleida, Hospital Universitari Arnau de Vilanova, Clinical Neurosciences Group IRBLleida, Avda Rovira Roure 80, 25198, Lleida, Spain.
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6
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Yu HH, Ma XT, Ma X, Chen M, Chu YH, Wu LJ, Wang W, Qin C, Tian DS. Remote Limb Ischemic Postconditioning Protects Against Ischemic Stroke by Promoting Regulatory T Cells Thriving. J Am Heart Assoc 2021; 10:e023077. [PMID: 34726065 PMCID: PMC8751947 DOI: 10.1161/jaha.121.023077] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Remote limb ischemic postconditioning (RLIPoC) has been demonstrated to protect against ischemic stroke. However, the underlying mechanisms of RLIPoC mediating cross-organ protection remain to be fully elucidated. Methods and Results Ischemic stroke was induced by middle cerebral artery occlusion for 60 minutes. RLIPoC was performed with 3 cycles of 10-minute ischemia followed by 10-minute reperfusion of the bilateral femoral arteries immediately after middle cerebral artery reperfusion. The percentage of regulatory T cells (Tregs) in the spleen, blood, and brain was detected using flow cytometry, and the number of Tregs in the ischemic hemisphere was counted using transgenic mice with an enhanced green fluorescent protein-tagged Foxp3. Furthermore, the metabolic status was monitored dynamically using a multispectral optical imaging system. The Tregs were conditionally depleted in the depletion of Treg transgenic mice after the injection of the diphtheria toxin. The inflammatory response and neuronal apoptosis were investigated using immunofluorescent staining. Infarct volume and neurological deficits were evaluated using magnetic resonance imaging and the modified neurological severity score, respectively. The results showed that RLIPoC substantially reduced infarct volume, improved neurological function, and significantly increased Tregs in the spleen, blood, and ischemic hemisphere after middle cerebral artery occlusion. RLIPoC was followed by subsequent alteration in metabolites, such as flavin adenine dinucleotide and nicotinamide adenine dinucleotide hydrate, both in RLIPoC-conducted local tissues and circulating blood. Furthermore, nicotinamide adenine dinucleotide hydrate can mimic RLIPoC in increasing Tregs. Conversely, the depletion of Tregs using depletion of Treg mice compromised the neuroprotective effects conferred by RLIPoC. Conclusions RLIPoC protects against ischemic brain injury, at least in part by activating and maintaining the Tregs through the nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide hydrate pathway.
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Affiliation(s)
- Hai-Han Yu
- Department of Neurology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China
| | - Xiao-Tong Ma
- Department of Neurology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China.,Department of Neurology Shandong Provincial Hospital Shandong First Medical University Jinan China
| | - Xue Ma
- Department of Neurology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China
| | - Man Chen
- Department of Neurology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China
| | - Yun-Hui Chu
- Department of Neurology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China
| | - Long-Jun Wu
- Department of Neurology Mayo Clinic Rochester MN
| | - Wei Wang
- Department of Neurology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China
| | - Chuan Qin
- Department of Neurology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China
| | - Dai-Shi Tian
- Department of Neurology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China
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Huang Z, He Y, Li QJ, Wen H, Zhang XY, Tu RH, Zhong GQ. Postconditioning attenuates myocardial ischemia-reperfusion injury by inhibiting complement activation and upregulation of miR-499. Exp Ther Med 2021; 22:684. [PMID: 33986849 PMCID: PMC8111864 DOI: 10.3892/etm.2021.10116] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 02/22/2021] [Indexed: 01/04/2023] Open
Abstract
The complement system plays a vital role in myocardial ischemia/reperfusion (I/R) injury. microRNA (miR)-499 is involved in the cardioprotection of ischemic postconditioning (IPostC). The present study aimed to study the role of the complement system and miR-499 in IPostC. Rat hearts were subjected to coronary ligation for 30 min, followed by reperfusion for 2 h. IPostC was introduced at the onset of reperfusion with three cycles of reperfusion for 30 sec and coronary artery occlusion for 30 sec. To study the role of miR-499 in IPostC, adeno-associated virus (AAV) vectors of miR-499-5p (AAV-miR-499-5p) and miR-499-5p-sponge (AAV-miR-499-5p-sponge) were transfected via tail vein injection, followed by IPostC protocols. Cardiac injury as well as the status of local and systemic complement activation and inflammation were assessed. IPostC significantly attenuated I/R-induced rat cardiomyocyte apoptosis and the myocardial infarct size. These beneficial effects were accompanied by decreased local and circulating complement component (C)3a and C5a levels, decreased inflammatory marker expression, decreased NF-κB signaling and increased cardiac miR-499 expression. AAV-miR-499-5p prevented local and systemic complement activation and inflammation as well as enhanced the cardioprotection of IPostC, whereas AAV-miR-499-5p-sponge produced the opposite effects. In summary, IPostC protected the rat myocardium against I/R injury, by inhibiting local and systemic complement activation; inflammation; NF-κB signaling; and upregulation of miR-499. As such, miR-499 may have a critical role in IPostC-mediated cardioprotection against I/R injury.
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Affiliation(s)
- Zheng Huang
- Department of Cardiology, First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Yan He
- Department of Geriatric Cardiology, First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China.,Guangxi Key Laboratory of Precision Medicine in Cardio-Cerebrovascular Diseases Control and Prevention, Nanning, Guangxi 530021, P.R. China
| | - Qing-Jie Li
- Department of Cardiology, First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Hong Wen
- Department of Geriatric Cardiology, First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China.,Guangxi Key Laboratory of Precision Medicine in Cardio-Cerebrovascular Diseases Control and Prevention, Nanning, Guangxi 530021, P.R. China
| | - Xin-Yue Zhang
- Department of Geriatric Cardiology, First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Rong-Hui Tu
- Department of Geriatric Cardiology, First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China.,Guangxi Key Laboratory of Precision Medicine in Cardio-Cerebrovascular Diseases Control and Prevention, Nanning, Guangxi 530021, P.R. China
| | - Guo-Qiang Zhong
- Department of Cardiology, First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China.,Guangxi Key Laboratory of Precision Medicine in Cardio-Cerebrovascular Diseases Control and Prevention, Nanning, Guangxi 530021, P.R. China
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8
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Zhang Y, Ma L, Ren C, Liu K, Tian X, Wu D, Ding Y, Li J, Borlongan CV, Ji X. Immediate remote ischemic postconditioning reduces cerebral damage in ischemic stroke mice by enhancing leptomeningeal collateral circulation. J Cell Physiol 2018; 234:12637-12645. [PMID: 30536714 PMCID: PMC6590306 DOI: 10.1002/jcp.27858] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 11/15/2018] [Indexed: 12/22/2022]
Abstract
Remote ischemic postconditioning (RIPC) is a promising neuroprotective strategy for ischemic stroke. Here, we employed a focal ischemic stroke mouse model to test the hypothesis that poststroke collateral circulation as a potent mechanism of action underlying the therapeutic effects of immediate RIPC. During reperfusion of cerebral ischemia, the mice were randomly assigned to receive RIPC, granulocyte colony‐stimulating factor (G‐CSF) as a positive control, or no treatment. At 24 hr, we found RIPC and G‐CSF increased monocytes/macrophages in the dorsal brain surface and in the spleen, coupled with enhanced leptomeningeal collateral flow compared with nontreatment group. Blood monocytes depletion by 5‐fluorouracil (5‐FU) significantly limited the neuroprotection of RIPC or G‐CSF treatment. The protein expression of proangiogenic factors such as Ang‐2 was increased by ischemia, but treatment with either RIPC or G‐CSF showed no further upregulation. Thus, immediate RIPC confers neuroprotection, in part, by enhancing leptomeningeal collateral circulation in a mouse model of ischemic stroke.
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Affiliation(s)
- Ying Zhang
- Department of Neurobiology, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Xuanwu Hospital, Capital Medical University, Beijing, China.,Center of Stroke, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Longhui Ma
- Department of Neurobiology, Capital Medical University, Beijing, China.,Center of Stroke, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Changhong Ren
- Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Xuanwu Hospital, Capital Medical University, Beijing, China.,Center of Stroke, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Kaiyin Liu
- Department of Neurosurgery, Wayne State University School of Medicine, Detroit, Michigan
| | - Xin Tian
- Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Xuanwu Hospital, Capital Medical University, Beijing, China.,Center of Stroke, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Di Wu
- Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Xuanwu Hospital, Capital Medical University, Beijing, China.,Center of Stroke, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Yuchuan Ding
- Department of Neurosurgery, Wayne State University School of Medicine, Detroit, Michigan
| | - Junfa Li
- Department of Neurobiology, Capital Medical University, Beijing, China.,Center of Stroke, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Cesar V Borlongan
- Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, Florida
| | - Xunming Ji
- Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Xuanwu Hospital, Capital Medical University, Beijing, China.,Center of Stroke, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
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9
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Cerebral Ischemic Postconditioning Plays a Neuroprotective Role through Regulation of Central and Peripheral Glutamate. BIOMED RESEARCH INTERNATIONAL 2018; 2018:6316059. [PMID: 30112410 PMCID: PMC6077516 DOI: 10.1155/2018/6316059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 07/12/2018] [Indexed: 01/30/2023]
Abstract
Following cerebral ischemia/reperfusion (I/R) injury, a series of pathophysiological processes are stimulated in both the central nervous system (CNS) and the periphery, including, but not limited to, the peripheral immune and endocrine systems and underregulation of the neuroendocrine-immune network. Glutamate (Glu) is an important excitatory neurotransmitter in the CNS; its excitotoxicity following cerebral ischemia has been a focus of study for several decades. In addition, as a novel immunoregulator, Glu also regulates immune activity in both the CNS and periphery and may connect the CNS and periphery through regulation of the neuroendocrine-immune network. Ischemic postconditioning (IPostC) is powerful and activates various endogenous neuroprotective mechanisms following cerebral I/R, but only a few studies have focused on the mechanisms associated with Glu to date. Given that Glu plays an important and complex pathophysiological role, the understanding of Glu-related mechanisms of IPostC is an interesting area of research, which we review here.
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Li M, Wen Y, Zhang R, Xie F, Zhang G, Qin X. Adenoviral vector-induced silencing of RGMa attenuates blood-brain barrier dysfunction in a rat model of MCAO/reperfusion. Brain Res Bull 2018; 142:54-62. [PMID: 29935233 DOI: 10.1016/j.brainresbull.2018.06.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Revised: 06/15/2018] [Accepted: 06/18/2018] [Indexed: 12/29/2022]
Abstract
BACKGROUND Repulsive guidance molecule A (RGMa) is implicated in focal cerebral ischemia-reperfusion (I/R) injury, but its mechanisms are still largely unknown. This work focused on the effects of RGMa on the blood-brain barrier (BBB) after focal cerebral I/R injury. METHODS Sprague-Dawley (SD) rats were randomly divided into four groups: sham, middle cerebral artery occlusion (MCAO)/reperfusion (I/R), MCAO/reperfusion administered recombinant adenovirus expressing sh-con (I/R + sh-con) and MCAO/reperfusion administered recombinant adenovirus expressing sh-RGMa (I/R + sh-RGMa) groups. Infarct volume, brain edema and neurological scores were evaluated at 3 day after reperfusion. Evens blue leakage and transmission electron microscopy was performed. And the expression level of claudin-5 and ZO-1, CDC-42 and PAK-1, RGMa were detected by western blot. RESULTS Compared with I/R or I/R + sh-con groups, I/R + sh-RGMa group showed smaller infarction volume, attenuated brain edema, improved neurological scores and better BBB integrity, such as reduced Evans blue leakage and ultra-structural change. We also observed improved BBB function followed by down-regulation of MMP-9 and up-regulation of claudin-5 and ZO-1 in the I/R + sh-RGMa group. In addition, up-regulation of the CDC-42 and PAK-1 in the I/R + sh-RGMa group was obtained. CONCLUSIONS RGMa may be involved in I/R injury associated with BBB dysfunction via the CDC-42/PAK-1 signal pathway and may be a promising therapeutic target for I/R injury.
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Affiliation(s)
- Min Li
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China; Department of Neurology, Inner Mongolia People's Hospital, Hohhot, China
| | - Yuetao Wen
- Department of Neurosurgery, University-Town Hospital of Chongqing Medical University, Chongqing, China
| | - Rongrong Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Fei Xie
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Gang Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xinyue Qin
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
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Wang P, Xie R, Cheng M, Sapolsky R, Ji X, Zhao H. The mTOR cell signaling pathway is crucial to the long-term protective effects of ischemic postconditioning against stroke. Neurosci Lett 2018; 676:58-65. [PMID: 29605662 DOI: 10.1016/j.neulet.2018.03.062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 03/14/2018] [Accepted: 03/28/2018] [Indexed: 01/23/2023]
Abstract
Ischemic postconditioning (IPostC) protects against stroke, but few have studied the pathophysiological mechanisms of its long-term protective effects. Here, we investigated whether the mTOR pathway is involved in the long-term protective effects of IPostC. Stroke was induced in rats by distal middle cerebral artery occlusion (dMCAo) combined with 30 min of bilateral common carotid artery (CCA) occlusion, and IPostC was induced after the CCA release. Injury size and behavioral tests were measured up to 3 weeks post stroke. We used rapamycin and mTOR shRNA lentiviral vectors to inhibit mTOR activities, while S6K1 viral vectors, a main downstream mTOR gene, were used to promote mTOR activities. We found that rapamycin administration abolished the long-term protective effects of IPostC. In addition, IPostC promoted the presynaptic growth associated protein 43 (GAP-43) and the postsynaptic protein 95 (PSD-95) levels at 1 week post-stroke, which were reduced by rapamycin. Furthermore, rapamycin reduced phosphorylated mTOR (p-mTOR) protein levels measured at 3 weeks after stroke. These results were confirmed by mTOR shRNA transfection. Moreover, we found that injection of S6K1 viral vectors promoted GAP-43 and PSD-95 protein levels. We conclude that mTOR may play a crucial, protective role in brain damage after stroke and contribute to the protective effects of IPostC.
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Affiliation(s)
- Peng Wang
- Departments of Neurosurgery, Stanford University, Stanford, CA 94305, United States
| | - Rong Xie
- Departments of Neurosurgery, Stanford University, Stanford, CA 94305, United States; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Michelle Cheng
- Departments of Neurosurgery, Stanford University, Stanford, CA 94305, United States; Departments of Biological Sciences, Stanford University, Stanford, CA 94305, United States
| | - Robert Sapolsky
- Departments of Biological Sciences, Stanford University, Stanford, CA 94305, United States
| | - Xunming Ji
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical School, Beijing 100053, China.
| | - Heng Zhao
- Departments of Neurosurgery, Stanford University, Stanford, CA 94305, United States.
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Lu XX, Hong ZQ, Tan Z, Sui MH, Zhuang ZQ, Liu HH, Zheng XY, Yan TB, Geng DF, Jin DM. Nicotinic Acetylcholine Receptor Alpha7 Subunit Mediates Vagus Nerve Stimulation-Induced Neuroprotection in Acute Permanent Cerebral Ischemia by a7nAchR/JAK2 Pathway. Med Sci Monit 2017; 23:6072-6081. [PMID: 29274273 PMCID: PMC5747934 DOI: 10.12659/msm.907628] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Background The role of nicotinic acetylcholine receptor alpha7 subunit (a7nAchR) in the treatment of acute cerebral ischemia by VNS has not been thoroughly clarified to date. Therefore, this study aimed to investigate the specific role of a7nAchR and explore whether this process is involved in the mechanisms of VNS-induced neuroprotection in rats undergoing permanent middle cerebral artery occlusion (PMCAO) surgery. Material/Methods Rats received a7nAChR antagonist (A) or antagonist placebo injection for control (AC), followed by PMCAO and VNS treatment, whereas the a7nAChR agonist (P) was utilized singly without VNS treatment but only with PMCAO pretreatment. The rats were randomly divided into 6 groups: sham PMCAO, PMCAO, PMCAO+VNS, PMCAO+VNS+A, PMCAO+VNS+AC, and PMCAO+P. Neurological function and cerebral infarct volume were measured to evaluate the level of brain injury at 24 h after PMCAO or PMCAO-sham. Moreover, the related proteins levels of a7nAChR, p-JAK2, and p-STAT3 in the ischemic penumbra were assessed by Western blot analysis. Results Rats pretreated with VNS had significantly improved neurological function and reduced cerebral infarct volume after PMCAO injury (p<0.05). In addition, VNS enhanced the levels of a7nAchR, p-JAK2, and p-STAT3 in the ischemic penumbra (p<0.05). However, inhibition of a7nAchR not only attenuated the beneficial neuroprotective effects induced by VNS, but also decreased levels of p-JAK2 and p-STAT3. Strikingly, pharmacological activation of a7nAchR can partially substitute for VNS-induced beneficial neurological protection. Conclusions These results suggest that a7nAchR is a pivotal mediator of VNS-induced neuroprotective effects on PMCAO injury, which may be related to suppressed inflammation via activation of the a7nAchR/JAK2 anti-inflammatory pathway.
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Affiliation(s)
- Xin-Xin Lu
- Department of Rehabilitation Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China (mainland).,Department of Rehabilitation Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China (mainland)
| | - Zhong-Qiu Hong
- Department of Rehabilitation Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China (mainland)
| | - Zhi Tan
- Department of Physiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China (mainland)
| | - Ming-Hong Sui
- Department of Rehabilitation Medicine, Shenzhen Nanshan People's Hospital (The Sixth People's Hospital of Shenzhen), Shenzhen University, Shenzhen, Guangdong, China (mainland)
| | - Zhi-Qiang Zhuang
- Department of Rehabilitation Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China (mainland).,Guangdong Engineering Technology Research Center for Rehabilitation and Elderly Care, Guangdong, China (mainland)
| | - Hui-Hua Liu
- Department of Rehabilitation Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China (mainland).,Guangdong Engineering Technology Research Center for Rehabilitation and Elderly Care, Guangdong, China (mainland)
| | - Xiu-Yuan Zheng
- Department of Rehabilitation Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China (mainland).,Guangdong Engineering Technology Research Center for Rehabilitation and Elderly Care, Guangdong, China (mainland)
| | - Tie-Bin Yan
- Department of Rehabilitation Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China (mainland).,Guangdong Engineering Technology Research Center for Rehabilitation and Elderly Care, Guangdong, China (mainland)
| | - Deng-Feng Geng
- Department of Cardiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China (mainland)
| | - Dong-Mei Jin
- Department of Rehabilitation Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China (mainland).,Guangdong Engineering Technology Research Center for Rehabilitation and Elderly Care, Guangdong, China (mainland)
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Postconditioning-induced neuroprotection, mechanisms and applications in cerebral ischemia. Neurochem Int 2017; 107:43-56. [DOI: 10.1016/j.neuint.2017.01.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 01/04/2017] [Accepted: 01/08/2017] [Indexed: 02/07/2023]
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Li Z, Chen H, Lv J, Zhao R. The application and neuroprotective mechanisms of cerebral ischemic post-conditioning: A review. Brain Res Bull 2017; 131:39-46. [DOI: 10.1016/j.brainresbull.2017.03.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 03/06/2017] [Indexed: 01/17/2023]
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Kaur I, Kumar A, Jaggi AS, Singh N. Evidence for the role of histaminergic pathways in neuroprotective mechanism of ischemic postconditioning in mice. Fundam Clin Pharmacol 2017; 31:456-470. [DOI: 10.1111/fcp.12275] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 01/12/2017] [Accepted: 02/02/2017] [Indexed: 01/04/2023]
Affiliation(s)
- Indresh Kaur
- Pharmacology Division; Department of Pharmaceutical Sciences and Drug Research; Faculty of Medicine; Punjabi University; Patiala 147002 Punjab India
| | - Amit Kumar
- Pharmacology Division; Department of Pharmaceutical Sciences and Drug Research; Faculty of Medicine; Punjabi University; Patiala 147002 Punjab India
| | - Amteshwar S. Jaggi
- Pharmacology Division; Department of Pharmaceutical Sciences and Drug Research; Faculty of Medicine; Punjabi University; Patiala 147002 Punjab India
| | - Nirmal Singh
- Pharmacology Division; Department of Pharmaceutical Sciences and Drug Research; Faculty of Medicine; Punjabi University; Patiala 147002 Punjab India
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Overview of Experimental and Clinical Findings regarding the Neuroprotective Effects of Cerebral Ischemic Postconditioning. BIOMED RESEARCH INTERNATIONAL 2017; 2017:6891645. [PMID: 28473987 PMCID: PMC5394355 DOI: 10.1155/2017/6891645] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 01/07/2017] [Accepted: 01/16/2017] [Indexed: 12/15/2022]
Abstract
Research on attenuating the structural and functional deficits observed following ischemia-reperfusion has become increasingly focused on the therapeutic potential of ischemic postconditioning. In recent years, various methods and animal models of ischemic postconditioning have been utilized. The results of these numerous studies have indicated that the mechanisms underlying the neuroprotective effects of ischemic postconditioning may involve reductions in the generation of free radicals and inhibition of calcium overload, as well as the release of endogenous active substances, alterations in membrane channel function, and activation of protein kinases. Here we review the novel discovery, mechanism, key factors, and clinical application of ischemic postconditioning and discuss its implications for future research and problem of clinical practice.
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Ma J, Zhang L, He G, Tan X, Jin X, Li C. Transcutaneous auricular vagus nerve stimulation regulates expression of growth differentiation factor 11 and activin-like kinase 5 in cerebral ischemia/reperfusion rats. J Neurol Sci 2016; 369:27-35. [DOI: 10.1016/j.jns.2016.08.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 07/29/2016] [Accepted: 08/01/2016] [Indexed: 01/09/2023]
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Xu X, Gao Y, Zhai Z, Zhang S, Shan F, Feng J. Repulsive guidance molecule a blockade exerts the immunoregulatory function in DCs stimulated with ABP and LPS. Hum Vaccin Immunother 2016; 12:2169-2180. [PMID: 26986456 DOI: 10.1080/21645515.2016.1164361] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Repulsive guidance molecule a (RGMa) is an axonal guidance molecule that has recently found to exert function in immune system. This study evaluated the function of RGMa in modulation of dendritic cells (DCs) function stimulated with Achyranthes bidentata polysaccharide (ABP) and lipopolysaccharide (LPS) using a RGMa-neutralizing antibody. Compared with the Control-IgG/ABP and Control-IgG/LPS groups, DCs in the Anti-RGMa/ABP and Anti-RGMa/LPS groups 1) showed small, round cells with a few cell processes and organelles, and many pinocytotic vesicles; 2) had decreased MHC II, CD86, CD80, and CD40 expression; 3) displayed the decreased IL-12p70, IL-1β and TNF-α levels and increased IL-10 secretion; 4) had a high percentage of FITC-dextran uptake; and 5) displayed a reduced ability to drive T cell proliferation and reinforced T cell polarization toward a Th2 cytokine pattern. We conclude that DCs treated with RGMa-neutralizing antibodies present with tolerogenic and immunoregulatory characteristics, which provides new insights into further understanding of the function of RGMa.
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Affiliation(s)
- Xuxu Xu
- a Department of Neurology, Shengjing Hospital , Affiliated Hospital of China Medical University , Shenyang , PR China
| | - Yan Gao
- a Department of Neurology, Shengjing Hospital , Affiliated Hospital of China Medical University , Shenyang , PR China
| | - Zhiyong Zhai
- a Department of Neurology, Shengjing Hospital , Affiliated Hospital of China Medical University , Shenyang , PR China
| | - Shuo Zhang
- a Department of Neurology, Shengjing Hospital , Affiliated Hospital of China Medical University , Shenyang , PR China
| | - Fengping Shan
- b Department of Immunology, School of Basic Medical Science , China Medical University , Shenyang , PR China
| | - Juan Feng
- a Department of Neurology, Shengjing Hospital , Affiliated Hospital of China Medical University , Shenyang , PR China
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Xu X, Gao Y, Shan F, Feng J. A novel role for RGMa in modulation of bone marrow-derived dendritic cells maturation induced by lipopolysaccharide. Int Immunopharmacol 2016; 33:99-107. [PMID: 26896667 DOI: 10.1016/j.intimp.2016.02.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 01/16/2016] [Accepted: 02/08/2016] [Indexed: 02/06/2023]
Abstract
Repulsive guidance molecule a (RGMa) is known to mediate immune responses and has been indicated to modulates T cell activation and autoimmune diseases by dendritic cells (DCs), which hints its significant function in the latter cells. The aim of our study, therefore, was to evaluate the function of RGMa in DC maturation. We found that small interfering RNA (siRNA) successfully silenced the expression of RGMa in DCs. Even after LPS stimulation, RGMa-silenced DCs displayed an immature morphology, characterized by small, round cells with a few cell processes and organelles, and many pinocytotic vesicles. In the presence of LPS, RGMa siRNA transfection markedly reduced levels of CD80, CD86, CD40, and MHC II expression, as well as the secretion of IL-12p70 and TNF-α. With LPS treatment, RGMa siRNA-transfected DCs also showed increased levels of IL-10 and endocytosis. Moreover, in the presence of LPS, RGMa siRNA-transfected DCs displayed a low ability to induce T cell proliferation and differentiation, compared with negative control (NTi)-transfected or control DCs (p<0.05 for both). We conclude that after LPS stimulation, RGMa siRNA-transfected DCs show immunoregulatory and tolerogenic characteristics, which provides new insights into the immune system.
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Affiliation(s)
- Xuxu Xu
- Department of Neurology, Shengjing Hospital, Affiliated Hospital of China Medical University, Shenyang 110004, PR China
| | - Yan Gao
- Department of Neurology, Shengjing Hospital, Affiliated Hospital of China Medical University, Shenyang 110004, PR China
| | - Fengping Shan
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110000, PR China
| | - Juan Feng
- Department of Neurology, Shengjing Hospital, Affiliated Hospital of China Medical University, Shenyang 110004, PR China.
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Zong Y, Jiang L, Zhang M, Zhou F, Qi W, Li S, Yang H, Zou Y, Xia Q, Zhou X, Hu X, Wang T. Limb remote ischemic postconditioning protects cerebral ischemia from injury associated with expression of HIF-1α in rats. BMC Neurosci 2015; 16:97. [PMID: 26715469 PMCID: PMC4696280 DOI: 10.1186/s12868-015-0235-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 12/22/2015] [Indexed: 02/05/2023] Open
Abstract
Background Limb remote ischemic postconditioning (LRIP) can ameliorate cerebral ischemia–reperfusion injury (IRI), while the underlying mechanism remains elusive. Hypoxia-inducible factor 1α (HIF-1α) is an important transcription factor during cerebral ischemia damage. However, whether the neuroprotective effect of LRIP could be associated with HIF-1α is somewhat unclear. Here we tested the hypothesis that Limb remote ischemic postconditioning (LRIP) protecting brain from injury in middle cerebral artery occlusion (MCAO) rat model was associated with HIF-1α expression. Results LRIP was conducted with 3 cycles of 10 min occlusion/10 min reperfusion at the beginning of reperfusion. The analysis of neurobehavioral function and triphenyltetrazolium chloride (TTC) staining showed the neurological deficit, brain infarct and cerebral edema, caused by ischemia–reperfusion injury (IRI), were dramatically ameliorated in LRIP administrated animals. Meanwhile, the result of Q-PCR and western blot revealed that the overexpression of HIF-1α induced by IRI could be notably suppressed by LRIP treatment. Conclusions LRIP exhibits a protective effect against cerebral ischemia/reperfusion and the possible mechanism is associated with the suppression of HIF-1α in stroke rats.
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Affiliation(s)
- Yonghua Zong
- Department of Morphology Lab and Department of Graduate, Chengdu Medical College, Sichuan, 610500, China.
| | - Ling Jiang
- Department of Anesthesiology and Institute of Neurological Disease, State Key Laboratory of Biotherapy, West China Hospital, Sichuan, 610041, China.
| | - Mingxiao Zhang
- Department of Morphology Lab and Department of Graduate, Chengdu Medical College, Sichuan, 610500, China.
| | - Fangfang Zhou
- Department of Morphology Lab and Department of Graduate, Chengdu Medical College, Sichuan, 610500, China.
| | - Wenqian Qi
- Department of Anesthesiology and Institute of Neurological Disease, State Key Laboratory of Biotherapy, West China Hospital, Sichuan, 610041, China.
| | - Shuai Li
- Department of Morphology Lab and Department of Graduate, Chengdu Medical College, Sichuan, 610500, China.
| | - Huijun Yang
- Department of Morphology Lab and Department of Graduate, Chengdu Medical College, Sichuan, 610500, China.
| | - Yu Zou
- Department of Anesthesiology and Institute of Neurological Disease, State Key Laboratory of Biotherapy, West China Hospital, Sichuan, 610041, China.
| | - Qingjie Xia
- Department of Anesthesiology and Institute of Neurological Disease, State Key Laboratory of Biotherapy, West China Hospital, Sichuan, 610041, China.
| | - Xue Zhou
- Department of Histology, Embryology and Neurobiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - Xiaosong Hu
- Department of Morphology Lab and Department of Graduate, Chengdu Medical College, Sichuan, 610500, China.
| | - Tinghua Wang
- Institute of Neuroscience, Kunming Medical University, Kunming, 650031, China. .,Department of Anesthesiology and Institute of Neurological Disease, State Key Laboratory of Biotherapy, West China Hospital, Sichuan, 610041, China.
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Martins AF, Xavier Neto J, Azambuja A, Sereno ML, Figueira A, Campos-Junior PH, Rosário MF, Toledo CBB, Silva GAB, Kitten GT, Coutinho LL, Dietrich S, Jorge EC. Repulsive Guidance Molecules a, b and c Are Skeletal Muscle Proteins, and Repulsive Guidance Molecule a Promotes Cellular Hypertrophy and Is Necessary for Myotube Fusion. Cells Tissues Organs 2015; 200:326-38. [PMID: 26397945 DOI: 10.1159/000433491] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2015] [Indexed: 11/19/2022] Open
Abstract
Repulsive guidance molecules (RGMs) compose a family of glycosylphosphatidylinositol (GPI)-anchored axon guidance molecules and perform several functions during neural development. New evidence has suggested possible new roles for these axon guidance molecules during skeletal muscle development, which has not been investigated thus far. In the present study, we show that RGMa, RGMb and RGMc are all induced during skeletal muscle differentiation in vitro. Immunolocalization performed on adult skeletal muscle cells revealed that RGMa, RGMb and RGMc are sarcolemmal proteins. Additionally, RGMa was found to be a sarcoplasmic protein with a surprisingly striated pattern. RGMa colocalization with known sarcoplasmic proteins suggested that this axon guidance molecule is a skeletal muscle sarcoplasmic protein. Western blot analysis revealed two RGMa fragments of 60 and 33 kDa, respectively, in adult skeletal muscle samples. RGMa phenotypes in skeletal muscle cells (C2C12 and primary myoblasts) were also investigated. RGMa overexpression produced hypertrophic cells, whereas RGMa knockdown resulted in the opposite phenotype. RGMa knockdown also blocked myotube formation in both skeletal muscle cell types. Our results are the first to show an axon guidance molecule as a skeletal muscle sarcoplasmic protein and to include RGMa in a system that regulates skeletal muscle cell size and differentiation.
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Affiliation(s)
- Aline Fagundes Martins
- Departamento de Morfologia, Instituto de Cix00EA;ncias Biolx00F3;gicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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Chen H, Wang L, Xing BZ, Liu XH, Chen ZY, Weng XD, Qiu T, Liu L. Ischemic postconditioning attenuates inflammation in rats following renal ischemia and reperfusion injury. Exp Ther Med 2015; 10:513-518. [PMID: 26622346 DOI: 10.3892/etm.2015.2514] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Accepted: 11/13/2014] [Indexed: 12/30/2022] Open
Abstract
Ischemic postconditioning (IPoC) involves a series of brief rapid intermittent ischemic episodes applied at the onset of reperfusion in the previously ischemic tissue or organ. Previous studies have demonstrated that IPoC attenuates tissue damage induced by ischemia and reperfusion (I/R) injury. The aim of the present study was to investigate whether IPoC has a beneficial effect on inflammation in a rat model of renal I/R injury. Wistar rats were subjected to 45 min of ischemia followed by 24, 72 or 120 h of reperfusion (I/R group). In the IPoC group, rats subjected to I/R were treated with six cycles of 10 sec reperfusion followed by a 10-sec ischemic episode. Blood samples were collected for the determination of blood urea nitrogen (BUN) and creatinine (Cr) levels. Furthermore, histological examination and immunohistochemical staining for the localization of nuclear factor-κB (NF-κB) were performed. In addition, quantitative polymerase chain reaction (qPCR) analysis was used to determine the expression levels of intercellular adhesion molecule-1 (ICAM-1), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), while western blot analysis was used to detect the protein expression levels of NF-κB. The results indicated that the BUN and Cr levels increased significantly in the I/R group, while the IPoC rats showed evidently reduced renal damage. Immunohistochemical analysis revealed that the expression levels of NF-κB were decreased by IPoC. In addition, the qPCR results revealed that IPoC significantly inhibited the increased mRNA expression levels of ICAM-1, IL-6 and TNF-α, induced by I/R injury. Western blot analysis indicated that the expression levels of NF-κB were upregulated in the I/R group, while IPoC was shown to inhibit the expression. In conclusion, IPoC was demonstrated to exhibit potent anti-inflammatory properties against renal I/R injury.
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Affiliation(s)
- Hui Chen
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Lei Wang
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Bian-Zhi Xing
- Department of Radiology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Xiu-Heng Liu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Zhi-Yuan Chen
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Xiao-Dong Weng
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Tao Qiu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Lin Liu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
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Yu L, Fan SJ, Liu L, Xiao M, Lin XJ, Liu Y, Lv HX, Chen XL, Liu JX. Effect of ischemic postconditioning on cerebral edema and the AQP4 expression following hypoxic-eschemic brain damage in neonatal rats. World J Pediatr 2015; 11:165-70. [PMID: 25410667 DOI: 10.1007/s12519-014-0519-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 03/03/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND A rat model for neonatal hypoxic-ischemic brain damage (HIBD) was established to observe the effect of ischemic postconditioning (IPostC) on cerebral edema and the AQP4 expression following HIBD and to verify the neuroprotection of IPostC and the relationship between changes of AQP4 expression and cerebral edema. METHODS Water content was measured with dry-wet method, and AQP4 transcription and the protein expression of the lesions were detected with real-time PCR and immunohistochemistry staining, respectively. RESULTS Within 6-48 hours, the degree of ipsilateral cerebral edema was significantly lower in IPostC-15 s/15 s group than in HIBD group. Similar to the HIBD group, the AQP4 transcription and expression in the IPostC group showed a downward and then upward trend. But the expression was still more evident in the HIBD group than in the IPostC-15 s/15 s group. From 24 to 48 hours, IPostC-15 s/15 s decreased the slowing down expression of AQP4. CONCLUSION IPostC has neuroprotective effect on neonatal rats with HIBD and it may relieve cerebral edema by regulating the expression of AQP4.
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Affiliation(s)
- Ling Yu
- Department of Neonatology, First Affiliated Hospital, Xi'an Jiaotong University School of Medicine, Xi'an, 710061, China
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Yao HC, Yang LJ, Han QF, Wang LH, Wu L, Zhang CY, Tian KL, Zhang M. Postconditioning with simvastatin decreases myocardial injury in rats following acute myocardial ischemia. Exp Ther Med 2015; 9:1166-1170. [PMID: 25780404 PMCID: PMC4353796 DOI: 10.3892/etm.2015.2273] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 01/19/2015] [Indexed: 11/10/2022] Open
Abstract
The aim of the present study was to investigate whether postconditioning with simvastatin attenuated myocardial ischemia reperfusion injury by inhibiting the expression of high mobility group box 1 (HMGB1) in rat myocardium following acute myocardial ischemia. In total, 30 male Sprague-Dawley rats were divided into sham operation (sham; n=10), acute myocardial infarction (AMI; n=10) and simvastatin (sim; n=10) groups. The AMI and sim groups were subjected to ischemia for 30 min, followed by reperfusion for 180 min. The rats in the sim group were administered 20 mg/kg simvastatin intravenously 5 min prior to reperfusion. Subsequently, the infarct size, serum cardiac troponin (c-TnI), tumor necrosis factor (TNF)-α and myocardial malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were measured. Western blot analysis was used to detect the protein expression of HMGB1. Postconditioning with simvastatin was shown to decrease the infarct size and HMGB1 expression levels in the myocardium following AMI (P<0.05). In addition, postconditioning with simvastatin not only decreased the serum levels of c-TnI and TNF-α (P<0.05), but also inhibited the increase in MDA levels and the reduction in SOD activity (P<0.05). Therefore, postconditioning with simvastatin was shown to attenuate myocardial injury. The underlying mechanism may be associated with the downregulation of HMGB1 expression in the ischemic myocardium.
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Affiliation(s)
- Heng-Chen Yao
- Department of Cardiology, Qilu Hospital of Shandong University School of Medicine, Jinan, Shandong 250012, P.R. China ; Department of Cardiology, Liaocheng People's Hospital of Taishan Medical University, Liaocheng, Shandong 252000, P.R. China
| | - Lan-Ju Yang
- Department of Cardiology, Liaocheng People's Hospital of Taishan Medical University, Liaocheng, Shandong 252000, P.R. China
| | - Qian-Feng Han
- Department of Cardiology, Liaocheng People's Hospital of Taishan Medical University, Liaocheng, Shandong 252000, P.R. China
| | - Lan-Hua Wang
- Department of Cardiology, Liaocheng People's Hospital of Taishan Medical University, Liaocheng, Shandong 252000, P.R. China
| | - Lei Wu
- Department of Cardiology, Liaocheng People's Hospital of Taishan Medical University, Liaocheng, Shandong 252000, P.R. China
| | - Chun-Yan Zhang
- Department of Cardiology, Liaocheng People's Hospital of Taishan Medical University, Liaocheng, Shandong 252000, P.R. China
| | - Ke-Li Tian
- Department of Biochemistry and Molecular Biology, ShandongUniversity School of Medicine, Jinan, Shandong 250012, P.R. China
| | - Mei Zhang
- Department of Cardiology, Qilu Hospital of Shandong University School of Medicine, Jinan, Shandong 250012, P.R. China
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Tu Q, Cao H, Zhong W, Ding B, Tang X. Atorvastatin protects against cerebral ischemia/reperfusion injury through anti-inflammatory and antioxidant effects. Neural Regen Res 2014; 9:268-75. [PMID: 25206811 PMCID: PMC4146150 DOI: 10.4103/1673-5374.128220] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2013] [Indexed: 01/28/2023] Open
Abstract
In addition to its lipid-lowering effect, atorvastatin exerts anti-inflammatory and antioxidant effects as well. In this study, we hypothesized that atorvastatin could protect against cerebral ischemia/reperfusion injury. The middle cerebral artery ischemia/reperfusion model was established, and atorvastatin, 6.5 mg/kg, was administered by gavage. We found that, after cerebral ischemia/reperfusion injury, levels of the inflammation-related factors E-selectin and myeloperoxidase were upregulated, the oxidative stress-related marker malondialdehyde was increased, and superoxide dismutase activity was decreased in the ischemic cerebral cortex. Atorvastatin pretreatment significantly inhibited these changes. Our findings indicate that atorvastatin protects against cerebral ischemia/reperfusion injury through anti-inflammatory and antioxidant effects.
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Affiliation(s)
- Qiuyun Tu
- Department of Geriatrics, Third Xiangya Hospital of Central South University, Changsha, Hunan Province, China
| | - Hui Cao
- Department of Neurology, Second Xiangya Hospital of Central South University, Changsha, Hunan Province, China
| | - Wei Zhong
- Department of Neurology, Second Xiangya Hospital of Central South University, Changsha, Hunan Province, China
| | - Binrong Ding
- Department of Geriatrics, Third Xiangya Hospital of Central South University, Changsha, Hunan Province, China
| | - Xiangqi Tang
- Department of Neurology, Second Xiangya Hospital of Central South University, Changsha, Hunan Province, China
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Jiang Y, Li L, Liu B, Zhang Y, Chen Q, Li C. Vagus nerve stimulation attenuates cerebral ischemia and reperfusion injury via endogenous cholinergic pathway in rat. PLoS One 2014; 9:e102342. [PMID: 25036185 PMCID: PMC4103831 DOI: 10.1371/journal.pone.0102342] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 06/16/2014] [Indexed: 12/02/2022] Open
Abstract
Inflammation and apoptosis play critical roles in the acute progression of ischemic injury pathology. Emerging evidence indicates that vagus nerve stimulation (VNS) following focal cerebral ischemia and reperfusion (I/R) may be neuroprotective by limiting infarct size. However, the underlying molecular mechanisms remain unclear. In this study, we investigated whether the protective effects of VNS in acute cerebral I/R injury were associated with anti-inflammatory and anti-apoptotic processes. Male Sprague-Dawley (SD) rats underwent VNS at 30 min after focal cerebral I/R surgery. Twenty-four h after reperfusion, neurological deficit scores, infarct volume, and neuronal apoptosis were evaluated. In addition, the levels of pro-inflammatory cytokines were detected using enzyme-linked immune sorbent assay (ELISA), and immunofluorescence staining for the endogenous "cholinergic anti-inflammatory pathway" was also performed. The protein expression of a7 nicotinic acetylcholine receptor (a7nAchR), phosphorylated Akt (p-Akt), and cleaved caspase 3 in ischemic penumbra were determined with Western blot analysis. I/R rats treated with VNS (I/R+VNS) had significantly better neurological deficit scores, reduced cerebral infarct volume, and decreased number of TdT mediated dUTP nick end labeling (TUNEL) positive cells. Furthermore, in the ischemic penumbra of the I/R+VNS group, the levels of pro-inflammatory cytokines and cleaved caspase 3 protein were significantly decreased, and the levels of a7nAchR and phosphorylated Akt were significantly increased relative to the I/R alone group. These results indicate that VNS is neuroprotective in acute cerebral I/R injury by suppressing inflammation and apoptosis via activation of cholinergic and a7nAchR/Akt pathways.
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Affiliation(s)
- Ying Jiang
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Longling Li
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Bin Liu
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yanhong Zhang
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Qian Chen
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Changqing Li
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Xie R, Wang P, Cheng M, Sapolsky R, Ji X, Zhao H. Mammalian target of rapamycin cell signaling pathway contributes to the protective effects of ischemic postconditioning against stroke. Stroke 2014; 45:2769-76. [PMID: 25013017 DOI: 10.1161/strokeaha.114.005406] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Whether the mammalian target of rapamycin (mTOR) pathway is protective against brain injury from stroke or is detrimental is controversial, and whether it is involved in the protective effects of ischemic postconditioning (IPC) against stroke is unreported. Our study focuses on the protective role of mTOR against neuronal injury after stroke with and without IPC. METHODS We used both an in vitro oxygen-glucose deprivation model with a mixed neuronal culture and hypoxic postconditioning, as well as an in vivo stroke model with IPC. Rapamycin, a specific pharmacological inhibitor of mTOR, and mTOR short hairpin RNA lentiviral vectors were used to inhibit mTOR activity. A lentiviral vector expressing S6K1, a downstream molecule of mTOR, was used to confirm the protective effects of mTOR. Infarct sizes were measured and protein levels were examined by Western blot. RESULTS We report that stroke resulted in reduced levels of phosphorylated proteins in the mTOR pathway, including S6K1, S6, and 4EBP1, and that IPC increased these proteins. mTOR inhibition, both by the mTOR inhibitor rapamycin and by mTOR short hairpin RNA, worsened ischemic outcomes in vitro and in vivo and abolished the protective effects of hypoxic postconditioning and IPC on neuronal death in vitro and brain injury size in vivo. Overexpression of S6K1 mediated by lentiviral vectors significantly attenuated brain infarction. CONCLUSIONS mTOR plays a crucial protective role in brain damage after stroke and contributes to the protective effects of IPC.
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Affiliation(s)
- Rong Xie
- From the Departments of Neurosurgery (R.X., P.W., M.C., R.S., H.Z.) and Biological Sciences (M.C., R.S.), and Stanford Stroke Center (H.Z.), Stanford University, CA; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China (R.X.); and Department of Neurosurgery, Xuanwu Hospital, Capital Medical School, Beijing, China (P.W., X.J.)
| | - Peng Wang
- From the Departments of Neurosurgery (R.X., P.W., M.C., R.S., H.Z.) and Biological Sciences (M.C., R.S.), and Stanford Stroke Center (H.Z.), Stanford University, CA; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China (R.X.); and Department of Neurosurgery, Xuanwu Hospital, Capital Medical School, Beijing, China (P.W., X.J.)
| | - Michelle Cheng
- From the Departments of Neurosurgery (R.X., P.W., M.C., R.S., H.Z.) and Biological Sciences (M.C., R.S.), and Stanford Stroke Center (H.Z.), Stanford University, CA; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China (R.X.); and Department of Neurosurgery, Xuanwu Hospital, Capital Medical School, Beijing, China (P.W., X.J.)
| | - Robert Sapolsky
- From the Departments of Neurosurgery (R.X., P.W., M.C., R.S., H.Z.) and Biological Sciences (M.C., R.S.), and Stanford Stroke Center (H.Z.), Stanford University, CA; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China (R.X.); and Department of Neurosurgery, Xuanwu Hospital, Capital Medical School, Beijing, China (P.W., X.J.)
| | - Xunming Ji
- From the Departments of Neurosurgery (R.X., P.W., M.C., R.S., H.Z.) and Biological Sciences (M.C., R.S.), and Stanford Stroke Center (H.Z.), Stanford University, CA; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China (R.X.); and Department of Neurosurgery, Xuanwu Hospital, Capital Medical School, Beijing, China (P.W., X.J.).
| | - Heng Zhao
- From the Departments of Neurosurgery (R.X., P.W., M.C., R.S., H.Z.) and Biological Sciences (M.C., R.S.), and Stanford Stroke Center (H.Z.), Stanford University, CA; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China (R.X.); and Department of Neurosurgery, Xuanwu Hospital, Capital Medical School, Beijing, China (P.W., X.J.).
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Liang J, Luan Y, Lu B, Zhang H, Luo YN, Ge P. Protection of ischemic postconditioning against neuronal apoptosis induced by transient focal ischemia is associated with attenuation of NF-κB/p65 activation. PLoS One 2014; 9:e96734. [PMID: 24800741 PMCID: PMC4011781 DOI: 10.1371/journal.pone.0096734] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Accepted: 04/10/2014] [Indexed: 11/19/2022] Open
Abstract
Background and Purpose Accumulating evidences have demonstrated that nuclear factor κB/p65 plays a protective role in the protection of ischemic preconditioning and detrimental role in lethal ischemia-induced programmed cell death including apoptosis and autophagic death. However, its role in the protection of ischemic postconditioning is still unclear. Methods Rat MCAO model was used to produce transient focal ischemia. The procedure of ischemic postconditioning consisted of three cycles of 30 seconds reperfusion/reocclusion of MCA. The volume of cerebral infarction was measured by TTC staining and neuronal apoptosis was detected by TUNEL staining. Western blotting was used to analyze the changes in protein levels of Caspase-3, NF-κB/p65, phosphor- NF-κB/p65, IκBα, phosphor- IκBα, Noxa, Bim and Bax between rats treated with and without ischemic postconditioning. Laser scanning confocal microscopy was used to examine the distribution of NF-κB/p65 and Noxa. Results Ischemic postconditioning made transient focal ischemia-induced infarct volume decrease obviously from 38.6%±5.8% to 23.5%±4.3%, and apoptosis rate reduce significantly from 46.5%±6.2 to 29.6%±5.3% at reperfusion 24 h following 2 h focal cerebral ischemia. Western blotting analysis showed that ischemic postconditioning suppressed markedly the reduction of NF-κB/p65 in cytoplasm, but elevated its content in nucleus either at reperfusion 6 h or 24 h. Moreover, the decrease of IκBα and the increase of phosphorylated IκBα and phosphorylated NF-κB/p65 at indicated reperfusion time were reversed by ischemic postconditioning. Correspondingly, proapoptotic proteins Caspase-3, cleaved Caspase-3, Noxa, Bim and Bax were all mitigated significantly by ischemic postconditioning. Confocal microscopy revealed that ischemic postconditioning not only attenuated ischemia-induced translocation of NF-κB/p65 from neuronal cytoplasm to nucleus, but also inhibited the abnormal expression of proapoptotic protein Noxa within neurons. Conclusions We demonstrated in this study that the protection of ischemic postconditioning on neuronal apoptosis caused by transient focal ischemia is associated with attenuation of the activation of NF-κB/p65 in neurons.
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Affiliation(s)
- Jianmin Liang
- Department of Pediatrics, First hospital of Jilin University, Changchun, China
- Neuroscience Research Center, First hospital of Jilin University, Changchun, China
| | - Yongxin Luan
- Department of Neurosurgery, First hospital of Jilin University, Changchun, China
| | - Bin Lu
- Department of Neurosurgery, First hospital of Jilin University, Changchun, China
| | - Hongbo Zhang
- Department of Pediatrics, First hospital of Jilin University, Changchun, China
| | - Yi-nan Luo
- Department of Neurosurgery, First hospital of Jilin University, Changchun, China
- Neuroscience Research Center, First hospital of Jilin University, Changchun, China
| | - Pengfei Ge
- Department of Neurosurgery, First hospital of Jilin University, Changchun, China
- Neuroscience Research Center, First hospital of Jilin University, Changchun, China
- * E-mail:
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Protection of ischemic post conditioning against transient focal ischemia-induced brain damage is associated with inhibition of neuroinflammation via modulation of TLR2 and TLR4 pathways. J Neuroinflammation 2014; 11:15. [PMID: 24460643 PMCID: PMC3908918 DOI: 10.1186/1742-2094-11-15] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 01/16/2014] [Indexed: 12/18/2022] Open
Abstract
Background and purpose Ischemic postconditioning has been demonstrated to be a protective procedure to brain damage caused by transient focal ischemia/reperfusion. However, it is elusive whether the protection of postconditioning against brain damage and neuroinflammation is via regulating TLR2 and TLR4 pathways. In the present study, we examined the protection of ischemic postconditioning performed immediately prior to the recovery of cerebral blood supply on brain damage caused by various duration of ischemia and tested the hypothesis that its protection is via inhibition of neuroinflammation by modulating TLR2/TLR4 pathways. Methods Brain damage in rats was induced by using the middle cerebral artery occlusion (MCAO) model. Ischemic postconditioning consisting of fivecycles of ten seconds of ischemia and reperfusion was performed immediately following theischemic episode Theduration of administration of ischemic postconditioning was examined by comparing its effects on infarction volume, cerebral edema and neurological function in 2, 3, 4, 4.5and 6 hour ischemia groups. The protective mechanism of ischemic postconditioning was investigated by comparing its effects on apoptosis, production of the neurotoxic cytokine IL-1β and the transcription and expression of TLR2, TLR4 and IRAK4 in the 2 and 4.5 hour ischemia groups. Results Ischemic postconditioning significantly attenuated cerebral infarction, cerebral edema and neurological dysfunction in ischemia groups of up to 4 hours duration, but not in 4.5and 6 hour ischemia groups. It also inhibited apoptosis, production of IL-1β, abnormal transcription and expression of TLR2, TLR4 and IRAK4 in the 2 hour ischemia group, but not in the 4.5 hour ischemia group. Conclusions Ischemic postconditioning protected brain damage caused by 2, 3 and 4 hours of ischemia, but not by 4.5 and 6 hours of ischemia. The protection of ischemic postconditioning is associated with its inhibition of neuroinflammation via inhibition of TLR2 and TLR4 pathways.
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