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Lénárt N, Cserép C, Császár E, Pósfai B, Dénes Á. Microglia-neuron-vascular interactions in ischemia. Glia 2024; 72:833-856. [PMID: 37964690 DOI: 10.1002/glia.24487] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/24/2023] [Accepted: 10/24/2023] [Indexed: 11/16/2023]
Abstract
Cerebral ischemia is a devastating condition that results in impaired blood flow in the brain leading to acute brain injury. As the most common form of stroke, occlusion of cerebral arteries leads to a characteristic sequence of pathophysiological changes in the brain tissue. The mechanisms involved, and comorbidities that determine outcome after an ischemic event appear to be highly heterogeneous. On their own, the processes leading to neuronal injury in the absence of sufficient blood supply to meet the metabolic demand of the cells are complex and manifest at different temporal and spatial scales. While the contribution of non-neuronal cells to stroke pathophysiology is increasingly recognized, recent data show that microglia, the main immune cells of the central nervous system parenchyma, play previously unrecognized roles in basic physiological processes beyond their inflammatory functions, which markedly change during ischemic conditions. In this review, we aim to discuss some of the known microglia-neuron-vascular interactions assumed to contribute to the acute and delayed pathologies after cerebral ischemia. Because the mechanisms of neuronal injury have been extensively discussed in several excellent previous reviews, here we focus on some recently explored pathways that may directly or indirectly shape neuronal injury through microglia-related actions. These discoveries suggest that modulating gliovascular processes in different forms of stroke and other neurological disorders might have presently unexplored therapeutic potential in combination with neuroprotective and flow restoration strategies.
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Affiliation(s)
- Nikolett Lénárt
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| | - Csaba Cserép
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| | - Eszter Császár
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| | - Balázs Pósfai
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
| | - Ádám Dénes
- Momentum Laboratory of Neuroimmunology, Institute of Experimental Medicine, Budapest, Hungary
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2
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Ikeda T, Kawabori M, Zheng Y, Yamaguchi S, Gotoh S, Nakahara Y, Yoshie E, Fujimura M. Intranasal Administration of Mesenchymal Stem Cell-Derived Exosome Alleviates Hypoxic-Ischemic Brain Injury. Pharmaceutics 2024; 16:446. [PMID: 38675108 PMCID: PMC11053690 DOI: 10.3390/pharmaceutics16040446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 03/15/2024] [Accepted: 03/19/2024] [Indexed: 04/28/2024] Open
Abstract
Hypoxic-ischemic brain injury arises from inadequate oxygen delivery to the brain, commonly occurring following cardiac arrest, which lacks effective treatments. Recent studies have demonstrated the therapeutic potential of exosomes released from mesenchymal stem cells. Given the challenge of systemic dilution associated with intravenous administration, intranasal delivery has emerged as a promising approach. In this study, we investigate the effects of intranasally administered exosomes in an animal model. Exosomes were isolated from the cell supernatants using the ultracentrifugation method. Brain injury was induced in Sprague-Dawley rats through a transient four-vessel occlusion model. Intranasal administration was conducted with 3 × 108 exosome particles in 20 µL of PBS or PBS alone, administered daily for 7 days post-injury. Long-term cognitive behavioral assessments, biodistribution of exosomes, and histological evaluations of apoptosis and neuroinflammation were conducted. Exosomes were primarily detected in the olfactory bulb one hour after intranasal administration, subsequently distributing to the striatum and midbrain. Rats treated with exosomes exhibited substantial improvement in cognitive function up to 28 days after the insult, and demonstrated significantly fewer apoptotic cells along with higher neuronal cell survival in the hippocampus. Exosomes were found to be taken up by microglia, leading to a decrease in the expression of cytotoxic inflammatory markers.
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Affiliation(s)
- Takuma Ikeda
- Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Hokkaido, Japan; (T.I.); (Y.Z.); (S.G.); (Y.N.); (E.Y.); (M.F.)
| | - Masahito Kawabori
- Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Hokkaido, Japan; (T.I.); (Y.Z.); (S.G.); (Y.N.); (E.Y.); (M.F.)
| | - Yuyuan Zheng
- Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Hokkaido, Japan; (T.I.); (Y.Z.); (S.G.); (Y.N.); (E.Y.); (M.F.)
| | - Sho Yamaguchi
- Regenerative Medicine and Cell Therapy Laboratories, Kaneka, Kobe 650-0047, Hyogo, Japan;
| | - Shuho Gotoh
- Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Hokkaido, Japan; (T.I.); (Y.Z.); (S.G.); (Y.N.); (E.Y.); (M.F.)
| | - Yo Nakahara
- Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Hokkaido, Japan; (T.I.); (Y.Z.); (S.G.); (Y.N.); (E.Y.); (M.F.)
| | - Erika Yoshie
- Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Hokkaido, Japan; (T.I.); (Y.Z.); (S.G.); (Y.N.); (E.Y.); (M.F.)
| | - Miki Fujimura
- Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Hokkaido, Japan; (T.I.); (Y.Z.); (S.G.); (Y.N.); (E.Y.); (M.F.)
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3
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Liang S, Xu L, Xin X, Zhang R, Wu Y. Study on pyroptosis-related genes Casp8, Gsdmd and Trem2 in mice with cerebral infarction. PeerJ 2024; 12:e16818. [PMID: 38348100 PMCID: PMC10860548 DOI: 10.7717/peerj.16818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 12/30/2023] [Indexed: 02/15/2024] Open
Abstract
Objective Cerebral infarction is the main cause of death in patients with cerebrovascular diseases. Our research aimed to screen and validate pyroptosis-related genes in cerebral infarction for the targeted therapy of cerebral infarction. Methods and results A total of 1,517 differentially expressed genes (DEGs) were obtained by DESeq2 software analysis. Gene set enrichment analysis results indicated that genes of middle cerebral artery occlusion (MCAO) mice aged 3 months and 18 months were enriched in pyroptosis, respectively. Differentially expressed pyroptosis-related genes (including Aim2, Casp8, Gsdmd, Naip2, Naip5, Naip6 and Trem2) were obtained through intersection of DEGs and genes from pyroptosis Gene Ontology Term (GO:0070269), and they were up-regulated in the brain tissues of MCAO mice in GSE137482. In addition, Casp8, Gsdmd, and Trem2 were verified to be significantly up-regulated in MCAO mice in GSE93376. The evaluation of neurologic function and triphenyltetrazolium chloride staining showed that the MCAO mouse models were successfully constructed. Meanwhile, the expressions of TNF-α, pyroptosis-related proteins, Casp8, Gsdmd and Trem2 in MCAO mice were significantly up-regulated. We selected Trem2 for subsequent functional analysis. OGD treatment of BV2 cell in vitro significantly upregulated the expressions of Trem2. Subsequent downregulation of Trem2 expression in OGD-BV2 cells further increased the level of pyroptosis. Therefore, Trem2 is a protective factor regulating pyroptosis, thus influencing the progression of cerebral infarction. Conclusions Casp8, Gsdmd and Trem2 can regulate pyroptosis, thus affecting cerebral infarction.
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Affiliation(s)
- Shunli Liang
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
- The Second Clinical Medical College of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Linsheng Xu
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Xilin Xin
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Rongbo Zhang
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - You Wu
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
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Wang H, Li J, Zhang H, Wang M, Xiao L, Wang Y, Cheng Q. Regulation of microglia polarization after cerebral ischemia. Front Cell Neurosci 2023; 17:1182621. [PMID: 37361996 PMCID: PMC10285223 DOI: 10.3389/fncel.2023.1182621] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 05/22/2023] [Indexed: 06/28/2023] Open
Abstract
Stroke ranks second as a leading cause of death and permanent disability globally. Microglia, innate immune cells in the brain, respond rapidly to ischemic injury, triggering a robust and persistent neuroinflammatory reaction throughout the disease's progression. Neuroinflammation plays a critical role in the mechanism of secondary injury in ischemic stroke and is a significant controllable factor. Microglia activation takes on two general phenotypes: the pro-inflammatory M1 type and the anti-inflammatory M2 type, although the reality is more complex. The regulation of microglia phenotype is crucial to controlling the neuroinflammatory response. This review summarized the key molecules and mechanisms of microglia polarization, function, and phenotypic transformation following cerebral ischemia, with a focus on the influence of autophagy on microglia polarization. The goal is to provide a reference for the development of new targets for the treatment for ischemic stroke treatment based on the regulation of microglia polarization.
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Affiliation(s)
- Hao Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Province Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Jingjing Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Province Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Han Zhang
- School of Medicine, Nantong University, Nantong, China
| | - Mengyao Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Province Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Lifang Xiao
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Province Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Yitong Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Province Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Qiong Cheng
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Province Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
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5
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Zhang H, Liu J, Bingham D, Orr A, Kawabori M, Kim JY, Zheng Z, Lam TI, Massa SM, Swanson RA, Yenari MA. Use of Botulinum Toxin for Limb Immobilization for Rehabilitation in Rats with Experimental Stroke. Biomolecules 2023; 13:512. [PMID: 36979446 PMCID: PMC10046338 DOI: 10.3390/biom13030512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 03/07/2023] [Accepted: 03/09/2023] [Indexed: 03/15/2023] Open
Abstract
Motor rehabilitation strategies after unilateral stroke suggest that the immobilization of the healthy, unimpaired limb can promote the functional recovery of a paretic limb. In rodents, this has been modeled using casts, harnesses, and other means of restricting the use of the non-paretic forelimb in models of experimental stroke. Here, we evaluated an alternative approach, using botulinum toxin injections to limit the function of the non-paretic forelimb. Adult male rats were subjected to permanent ligation of the left distal middle cerebral artery, resulting in right forelimb paresis. The rats were then subjected to: (1) no treatment; (2) botulinum toxin injections 1 day post stroke; or (3) cast placement 5 days post stroke. Casts were removed after 5 weeks, while the botulinum toxin injection effectively immobilized subjects for approximately the same duration. Rats with bilateral forelimb impairment due to the stroke plus casting or botulinum injections were still able to feed and groom normally. Both immobilization groups showed modest recovery following the stroke compared to those that did not receive immobilization, but the casting approach led to unacceptable levels of animal stress. The botulinum toxin approach to limb immobilization had both advantages and disadvantages over traditional physical limb immobilization. The major advantage was that it was far less stress-inducing to the subject animals and appeared to be well tolerated. A disadvantage was that the paresis took roughly 10 weeks to fully resolve, and any degree of residual paresis could confound the interpretation of the behavioral assessments.
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Affiliation(s)
- Hongxia Zhang
- Department of Neurological Surgery, University of California, San Francisco, CA 94143, USA
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
| | - Jialing Liu
- Department of Neurological Surgery, University of California, San Francisco, CA 94143, USA
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
| | - Deborah Bingham
- Department of Neurological Surgery, University of California, San Francisco, CA 94143, USA
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
| | - Adrienne Orr
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
- Department of Neurology, University of California, San Francisco, CA 94143, USA
| | - Masahito Kawabori
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
- Department of Neurology, University of California, San Francisco, CA 94143, USA
- Department of Neurosurgery, Hokkaido University, Sapporo 060-0808, Japan
| | - Jong Youl Kim
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
- Department of Neurology, University of California, San Francisco, CA 94143, USA
- Department of Anatomy, Yonsei University, Seoul 03722, Republic of Korea
| | - Zhen Zheng
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
- Department of Neurology, University of California, San Francisco, CA 94143, USA
| | - Tina I. Lam
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
- Department of Neurology, University of California, San Francisco, CA 94143, USA
| | - Stephen M. Massa
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
- Department of Neurology, University of California, San Francisco, CA 94143, USA
| | - Raymond A. Swanson
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
- Department of Neurology, University of California, San Francisco, CA 94143, USA
| | - Midori A. Yenari
- San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, USA
- Department of Neurology, University of California, San Francisco, CA 94143, USA
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6
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Yang M, Wang Y, Wang S, Guo Y, Gu T, Shi L, Zhang J, Tuo X, Liu X, Zhang M, Deng J, Fang Z, Lu Z. Electroacupuncture pretreatment induces ischemic tolerance by neuronal TREM2-mediated enhancement of autophagic flux. Brain Res Bull 2023; 193:27-36. [PMID: 36470555 DOI: 10.1016/j.brainresbull.2022.11.021] [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: 06/30/2022] [Revised: 11/23/2022] [Accepted: 11/30/2022] [Indexed: 12/11/2022]
Abstract
The mechanism of electroacupuncture (EA) pretreatment-induced neuroprotection remains unclear. In this study, we found that neuronal Triggering receptor expressed on myeloid cells 2 (TREM2) expression was increased and peaked at 48 h and 72 h after ischemia/reperfusion. After specific knockdown of TREM2 in excitatory neurons, neurological function was damaged, and the infarct volume was enlarged. Furthermore, the expression of LC3II/LC3I and Beclin1 was decreased, while the expression of p62 was increased. EA pretreatment enhanced TREM2, LC3II/LC3I and Beclin1 expression while reducing p62 in the ischemic penumbra area. The EA-induced neuroprotective effects and improvements in autophagic flux were abolished by specific knockdown of TREM2 in excitatory neurons. Taken together, our findings provide novel mechanistic insight into EA-induced ischemic tolerance and suggest a promising therapeutic strategy of targeting neuronal TREM2 to treat brain ischemia.
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Affiliation(s)
- Manping Yang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Yunying Wang
- Department of Aerospace Physiology, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Shiquan Wang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Yaru Guo
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Ting Gu
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Liwen Shi
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Junbao Zhang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Xiaoshuang Tuo
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Xiaoyu Liu
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Minjuan Zhang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Jiao Deng
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China
| | - Zongping Fang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China.
| | - Zhihong Lu
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi 710032, China.
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7
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Takamiya S, Kawabori M, Yamazaki K, Yamaguchi S, Tanimori A, Yamamoto K, Ohnishi S, Seki T, Konno K, Tha KK, Hashimoto D, Watanabe M, Houkin K, Fujimura M. Intravenous transplantation of amnion-derived mesenchymal stem cells promotes functional recovery and alleviates intestinal dysfunction after spinal cord injury. PLoS One 2022; 17:e0270606. [PMID: 35802703 PMCID: PMC9269969 DOI: 10.1371/journal.pone.0270606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 06/13/2022] [Indexed: 11/19/2022] Open
Abstract
Spinal cord injury (SCI) is often accompanied by gastrointestinal dysfunction due to the disconnection of the spinal autonomic nervous system. Gastrointestinal dysfunction reportedly upregulates intestinal permeability, leading to bacterial translocation of the gut microbiome to the systemic circulation, which further activates systemic inflammation, exacerbating neuronal damage. Mesenchymal stem cells (MSC) reportedly ameliorate SCI. Here, we aimed to investigate their effect on the associated gastrointestinal dysfunction. Human amnion-derived MSC (AMSCs) were intravenously transplanted one day after a rat model of midthoracic SCI. Biodistribution of transplanted cells, behavioral assessment, and histological evaluations of the spinal cord and intestine were conducted to elucidate the therapeutic effect of AMSCs. Bacterial translocation of the gut microbiome was examined by in situ hybridization and bacterial culture of the liver. Systemic inflammations were examined by blood cytokines, infiltrating immune cells in the spinal cord, and the size of the peripheral immune tissue. AMSCs released various neurotrophic factors and were mainly distributed in the liver and lung after transplantation. AMSC-transplanted animals showed smaller spinal damage and better neurological recovery with preserved neuronal tract. AMSCs transplantation ameliorated intestinal dysfunction both morphologically and functionally, which prevented translocation of the gut microbiome to the systemic circulation. Systemic inflammations were decreased in animals receiving AMSCs in the chronic phase. Intravenous AMSC administration during the acute phase of SCI rescues both spinal damage and intestinal dysfunction. Reducing bacterial translocation may contribute to decreasing systemic inflammation.
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Affiliation(s)
- Soichiro Takamiya
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Masahito Kawabori
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
- * E-mail:
| | - Kazuyoshi Yamazaki
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Sho Yamaguchi
- Regenerative Medicine and Cell Therapy Laboratories, Kaneka Corporation, Kobe, Hyogo, Japan
| | - Aki Tanimori
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Koji Yamamoto
- Department of Gastroenterology and Hepatology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Shunsuke Ohnishi
- Laboratory of Molecular and Cellular Medicine, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Toshitaka Seki
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Kotaro Konno
- Department of Anatomy and Embryology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Khin Khin Tha
- Global Center for Biomedical Science and Engineering, Hokkaido University Faculty of Medicine, Sapporo, Hokkaido, Japan
| | - Daigo Hashimoto
- Department of Hematology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Masahiko Watanabe
- Department of Anatomy and Embryology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Kiyohiro Houkin
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Miki Fujimura
- Department of Neurosurgery, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
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8
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Ma WY, Wang SS, Wu QL, Zhou X, Chu SF, Chen NH. The versatile role of TREM2 in regulating of microglia fate in the ischemic stroke. Int Immunopharmacol 2022; 109:108733. [PMID: 35525233 DOI: 10.1016/j.intimp.2022.108733] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 03/07/2022] [Accepted: 03/22/2022] [Indexed: 12/15/2022]
Abstract
Microglia are the earliest activated and the longest lasting immune cells after stroke, and they participate in almost all the pathological reactions after stroke. However, their regulatory mechanism has not been fully elucidated. Triggering receptor expressed on myeloid cells-2 (TREM2) is a cell surface receptor that is mainly expressed in microglia of the central nervous system. The receptor plays an important role in regulating microglia energy metabolism and phenotypic transformation. At present, TREM2 has been developed as a potential target for AD, coronary atherosclerosis and other diseases. However, TREM2 does not provide a systematic summary of the functional transformation and intrinsic molecular mechanisms of microglia after stroke. In this paper, we have summarized the functional changes of TREM2 in microglia after stroke in recent years, and found that TREM2 has important effects on energy metabolism, phagocytosis and anti-inflammatory function of microglia after stroke, suggesting that TREM2 is a potential therapeutic target for the treatment of stroke.
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Affiliation(s)
- Wen-Yu Ma
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Sha-Sha Wang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Qing-Lin Wu
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Xin Zhou
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medical & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Shi-Feng Chu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medical & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Nai-Hong Chen
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China; State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medical & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
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9
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Mesenchymal Stem Cell Sheet Promotes Functional Recovery and Palliates Neuropathic Pain in a Subacute Spinal Cord Injury Model. Stem Cells Int 2021; 2021:9964877. [PMID: 34306098 PMCID: PMC8285204 DOI: 10.1155/2021/9964877] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 05/16/2021] [Accepted: 06/23/2021] [Indexed: 11/25/2022] Open
Abstract
Stem cell therapy has been shown to reverse the sequelae of spinal cord injury (SCI). Although the ideal treatment route remains unknown, providing a large number of stem cells to the injured site using less invasive techniques is critical to achieving maximal recovery. This study was conducted to determine whether administration of bone marrow stem cell (BMSC) sheet made on its own without a scaffold is superior to intramedullary cell transplantation in a rat subacute SCI model. Adult female Sprague-Dawley rats were subjected to SCI by 30 g clip compression at the level of Th6 and Th7 and were administered BMSC cell sheet (7 × 104 cells, subdural), cell suspension (7 × 104 cells, intramedullary), or control seven days after the injury. Motor and sensory assessments, as well as histological evaluation, were performed to determine the efficacy of the different cell transplantation procedures. While both the cell sheet and cell intramedullary injection groups showed significant motor recovery compared to the control group, the cell sheet group showed better results. Furthermore, the cell sheet group displayed a significant sensory recovery compared to the other groups. A histological evaluation revealed that the cell sheet group showed smaller injury lesion volume, less inflammation, and gliosis compared to other groups. Sensory-related fibers of μ-opioid receptors (MOR, interneuron) and hydroxytryptamine transporters (HTT, descending pain inhibitory pathway), located around the dorsal horn of the spinal cord at the caudal side of the SCI, were preserved only in the cell sheet group. Stem cells could also be found inside the peri-injured spinal cord in the cell sheet group. BMSC cell sheets were able to promote functional recovery and palliate neuropathic pain more effectively than intramedullary injections, thus serving as a good treatment option for SCI.
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10
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Clinical Trials of Stem Cell Therapy for Cerebral Ischemic Stroke. Int J Mol Sci 2020; 21:ijms21197380. [PMID: 33036265 PMCID: PMC7582939 DOI: 10.3390/ijms21197380] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 09/24/2020] [Accepted: 10/02/2020] [Indexed: 12/17/2022] Open
Abstract
Despite recent developments in innovative treatment strategies, stroke remains one of the leading causes of death and disability worldwide. Stem cell therapy is currently attracting much attention due to its potential for exerting significant therapeutic effects on stroke patients. Various types of cells, including bone marrow mononuclear cells, bone marrow/adipose-derived stem/stromal cells, umbilical cord blood cells, neural stem cells, and olfactory ensheathing cells have enhanced neurological outcomes in animal stroke models. These stem cells have also been tested via clinical trials involving stroke patients. In this article, the authors review potential molecular mechanisms underlying neural recovery associated with stem cell treatment, as well as recent advances in stem cell therapy, with particular reference to clinical trials and future prospects for such therapy in treating stroke.
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Chen S, Peng J, Sherchan P, Ma Y, Xiang S, Yan F, Zhao H, Jiang Y, Wang N, Zhang JH, Zhang H. TREM2 activation attenuates neuroinflammation and neuronal apoptosis via PI3K/Akt pathway after intracerebral hemorrhage in mice. J Neuroinflammation 2020; 17:168. [PMID: 32466767 PMCID: PMC7257134 DOI: 10.1186/s12974-020-01853-x] [Citation(s) in RCA: 156] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 05/21/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Neuroinflammation is an important host defense response to secondary brain injury after intracerebral hemorrhage (ICH). Triggering receptor expressed on myeloid cells 2 (TREM2) confers strong neuroprotective effects by attenuating neuroinflammation in experimental ischemic stroke. Recent studies suggest that apolipoprotein E (apoE) is a novel, high-affinity ligand of TREM2. This study aimed to investigate the effects of TREM2 activation on neuroinflammation and neuronal apoptosis in a mouse model of ICH. METHODS Adult male CD1 mice (n = 216) were subjected to intrastriatal injection of bacterial collagenase. The TREM2 ligand, apoE-mimetic peptide COG1410 was administered intranasally at 1 h after ICH induction. To elucidate the underlying mechanism, TREM2 small interfering RNA (siRNA) and the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 were administered intracerebroventricularly prior to COG1410 treatment. Neurobehavioral tests, brain water content, immunofluorescence, western blotting, and Fluoro-Jade C- and terminal deoxynucleotidyl transferase dUTP nick end labeling staining were performed. RESULTS Endogenous TREM2 expression was increased and peaked at 24 h after ICH. TREM2 was expressed on microglia, astrocytes, and neurons. COG1410 improved both short-term and long-term neurological functions, reduced brain edema, inhibited microglia/macrophage activation and neutrophil infiltration, and suppressed neuronal apoptotic cell death in perihematomal areas after ICH. Knockdown of endogenous TREM2 by TREM2 siRNA aggravated neurological deficits and decreased the expression of TREM2 in naïve and ICH mice. COG1410 was associated with upregulation of TREM2, PI3K, phosphorylated-Akt, and Bcl-2 and downregulation of TNF-α, IL-1β, and Bax after ICH. The neuroprotective effects of COG1410 were abolished by both TREM2 siRNA and PI3K inhibitor LY294002. CONCLUSIONS Our finding demonstrated that TREM2 activation improved neurological functions and attenuated neuroinflammation and neuronal apoptosis after ICH, which was, at least in part, mediated by activation of PI3K/Akt signaling pathway. Therefore, activation of TREM2 may be a potential therapeutic strategy for the management of ICH patients.
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Affiliation(s)
- Shengpan Chen
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China International Neuroscience Institute (China-INI), No. 45 Changchun Street, Xicheng District, Beijing, 10053, China
- Department of Physiology and Pharmacology, Department of Neurosurgery and Anesthesiology, School of Medicine, Loma Linda University, Risley Hall, Room 219, 11041 Campus Street, Loma Linda, CA, 92354, USA
| | - Jianhua Peng
- Department of Physiology and Pharmacology, Department of Neurosurgery and Anesthesiology, School of Medicine, Loma Linda University, Risley Hall, Room 219, 11041 Campus Street, Loma Linda, CA, 92354, USA
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, China
| | - Prativa Sherchan
- Department of Physiology and Pharmacology, Department of Neurosurgery and Anesthesiology, School of Medicine, Loma Linda University, Risley Hall, Room 219, 11041 Campus Street, Loma Linda, CA, 92354, USA
| | - Yongjie Ma
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China International Neuroscience Institute (China-INI), No. 45 Changchun Street, Xicheng District, Beijing, 10053, China
| | - Sishi Xiang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China International Neuroscience Institute (China-INI), No. 45 Changchun Street, Xicheng District, Beijing, 10053, China
| | - Feng Yan
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China International Neuroscience Institute (China-INI), No. 45 Changchun Street, Xicheng District, Beijing, 10053, China
| | - Hao Zhao
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China International Neuroscience Institute (China-INI), No. 45 Changchun Street, Xicheng District, Beijing, 10053, China
| | - Yong Jiang
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, China
- Laboratory of Neurological Diseases and Brain Functions, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
| | - Ning Wang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China International Neuroscience Institute (China-INI), No. 45 Changchun Street, Xicheng District, Beijing, 10053, China
| | - John H Zhang
- Department of Physiology and Pharmacology, Department of Neurosurgery and Anesthesiology, School of Medicine, Loma Linda University, Risley Hall, Room 219, 11041 Campus Street, Loma Linda, CA, 92354, USA.
- Department of Neurosurgery, Loma Linda University Medical Center, Loma Linda, CA, 92354, USA.
| | - Hongqi Zhang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China International Neuroscience Institute (China-INI), No. 45 Changchun Street, Xicheng District, Beijing, 10053, China.
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12
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Yamazaki K, Kawabori M, Seki T, Takamiya S, Tateno T, Konno K, Watanabe M, Houkin K. FTY720 Attenuates Neuropathic Pain after Spinal Cord Injury by Decreasing Systemic and Local Inflammation in a Rat Spinal Cord Compression Model. J Neurotrauma 2020; 37:1720-1728. [PMID: 32216535 PMCID: PMC7368387 DOI: 10.1089/neu.2019.6905] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Neuropathic pain severely impairs rehabilitation and quality of life after spinal cord injury (SCI). The sphingosine-1-phosphate receptor agonist, FTY720, plays an important protective role in neuronal injury. This study aims to examine the effects of FTY720 in a rat acute SCI model, focusing on neuropathic pain. Female rats with SCI induced by 1-min clip compression were administered vehicle or 1.5 mg/kg of FTY720 24 h after the injury. Using the mechanical nociceptive threshold test, we monitored neuropathic pain and performed histological analysis of the pain pathway, including the μ opioid receptor (MOR), hydroxytryptamine transporter (HTT), and calcitonin gene-related peptide (CGRP). Motor score, SCI lesion volume, residual motor axons, inflammatory response, glial scar, and microvascular endothelial dysfunction were also compared between the two groups. FTY720 treatment resulted in significant attenuation of post-traumatic neuropathic pain. It also decreased systemic and local inflammation, thereby reducing the damaged areas and astrogliosis and resulting in motor functional recovery. Whereas there was no difference in the CGRP expression between the two groups, FTY720 significantly preserved the MOR in both the caudal and rostral areas of the spinal dorsal horn. Whereas HTT was preserved in the FTY720 group, it was significantly increased in the rostral side and decreased in the caudal side of the injury in the vehicle group. These results suggest that FTY720 ameliorates post-traumatic allodynia through regulation of neuroinflammation, maintenance of the blood-brain barrier, and inhibition of glial scar formation, thereby preserving the connectivity of the descending inhibitory pathway and reducing neuropathic pain.
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Affiliation(s)
- Kazuyoshi Yamazaki
- Department of Neurosurgery, Graduate School of Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Masahito Kawabori
- Department of Neurosurgery, Graduate School of Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
- Department of Neurological Cell Therapy, Hokkaido University Hospital, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
- Address correspondence to: Masahito Kawabori, MD, Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Toshitaka Seki
- Department of Neurosurgery, Graduate School of Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Soichiro Takamiya
- Department of Neurosurgery, Graduate School of Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Takahiro Tateno
- Department of Hematology, Graduate School of Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Kotaro Konno
- Department of Anatomy and Embryology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Masahiko Watanabe
- Department of Anatomy and Embryology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Kiyohiro Houkin
- Department of Neurosurgery, Graduate School of Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
- Department of Neurological Cell Therapy, Hokkaido University Hospital, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
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13
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Singh J, Barrett J, Sangaletti R, Dietrich WD, Rajguru SM. Additive Protective Effects of Delayed Mild Therapeutic Hypothermia and Antioxidants on PC12 Cells Exposed to Oxidative Stress. Ther Hypothermia Temp Manag 2020; 11:77-87. [PMID: 32302519 DOI: 10.1089/ther.2019.0034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mild therapeutic hypothermia is protective against several cellular stresses, but the mechanisms underlying this protection are not completely resolved. In the present study, we used an in vitro model to investigate whether therapeutic hypothermia at 33°C applied following a peroxide-induced oxidative stress would protect PC12 cells. A 1-hour exposure to tert-butyl peroxide increased cell death measured 24 hours later. This cell death was dose-dependent in the range of 100-1000 μM tert-butyl peroxide with ∼50% cell death observed at 24 hours from 500 μM peroxide exposure. Cell survival/death was measured with an alamarBlue viability assay, and propidium iodide/Hoechst imaging for counts of living and dead cells. Therapeutic hypothermia at 33°C applied for 2 hours postperoxide exposure significantly increased cell survival measured 24 hours postperoxide-induced stress. This protection was present even when delayed hypothermia, 15 minutes after the peroxide washout, was applied. Addition of any of the three FDA-approved antioxidants (Tempol, EUK134, Edaravone at 100 μM) in combination with hypothermia improved cell survival. With the therapeutic hypothermia treatment, a significant downregulation of caspases-3 and -8 and tumor necrosis factor-α was observed at 3 and 24 hours poststress. Consistent with this, a cell-permeable pan-caspase inhibitor Z-VAD-FMK applied in combination with hypothermia significantly increased cell survival. Overall, these results suggest that the antioxidants quenching of reactive oxygen species likely works with hypothermia to reduce mitochondrial damage and/or apoptotic mechanisms. Further studies are required to confirm and extend these results to other cell types, including neuronal cells, and other forms of oxidative stress as well as to optimize the critical parameters of hypothermia treatment such as target temperature and duration.
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Affiliation(s)
- Jayanti Singh
- Department of Otolaryngology, University of Miami, Miami, Florida, USA
| | - John Barrett
- Department of Physiology and Biophysics, University of Miami, Miami, Florida, USA
| | | | - W Dalton Dietrich
- Department of Biomedical Engineering, University of Miami, Miami, Florida, USA.,Department of Neurological Surgery, University of Miami, Miami, Florida, USA
| | - Suhrud M Rajguru
- Department of Otolaryngology, University of Miami, Miami, Florida, USA.,Department of Biomedical Engineering, University of Miami, Miami, Florida, USA
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14
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Kurisu K, You J, Zheng Z, Won SJ, Swanson RA, Yenari MA. Cofilin-actin rod formation in experimental stroke is attenuated by therapeutic hypothermia and overexpression of the inducible 70 kD inducible heat shock protein (Hsp70). Brain Circ 2019; 5:225-233. [PMID: 31950099 PMCID: PMC6950512 DOI: 10.4103/bc.bc_52_19] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 11/26/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND AND PURPOSE Cofilin-actin rods are covalently linked aggregates of cofilin-1 and actin. Under ischemic conditions, these rods have been observed in neuronal dendrites and axons and may contribute to the loss of these processes. Hypothermia (Hypo) and the 70 kD inducible heat shock protein (Hsp70) are both known to improve outcomes after stroke, but the mechanisms are uncertain. Here, we evaluated the effect of these factors on cofilin-actin rod formation in a mouse model of stroke. MATERIALS AND METHODS Mice were subjected to distal middle cerebral artery occlusion (dMCAO) and treated with Hypo using a paradigm previously shown to be neuroprotective. We similarly studied mice that overexpressed transgenic (Tg) or were deficient knockout (Ko) in the inducible 70 kDa heat shock protein (Hsp70), also previously shown to be protective by our group and others. Cofilin-actin rod formation was assessed by histological analysis at 4 and 24 h after dMCAO. Its expression was analyzed in three different regions, namely, infarct core (the center of the infarct), middle cerebral artery (MCA) borderzone (the edge of the brain regions supplied by the MCA), and the ischemic borderzone (border of ischemic lesion). Ischemic lesion size and neurological deficits were also assessed. RESULTS Both Hypo-treated and Hsp70 Tg mice had smaller lesion sizes and improved neurological outcomes, whereas Hsp70 Ko mice had larger lesion sizes and worsened neurological outcomes. Cofilin-actin rods were increased after stroke, but were reduced by therapeutic Hypo and in Hsp70 Tg mice. In contrast, cofilin-actin rods were increased in ischemic brains of Hsp70 Ko mice. CONCLUSIONS Cofilin-actin rod formation was suppressed under the conditions of neuroprotection and increased under circumstances where outcome was worsened. This suggests that cofilin-actin rods may act to participate in or exacerbate ischemic pathology and warrants further study as a potential therapeutic target.
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Affiliation(s)
- Kota Kurisu
- University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Jesung You
- University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA.,Department of Emergency Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Zhen Zheng
- University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Seok Joon Won
- University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Raymond A Swanson
- University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Midori A Yenari
- University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
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15
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Kurisu K, Zheng Z, Kim JY, Shi J, Kanoke A, Liu J, Hsieh CL, Yenari MA. Triggering receptor expressed on myeloid cells-2 expression in the brain is required for maximal phagocytic activity and improved neurological outcomes following experimental stroke. J Cereb Blood Flow Metab 2019; 39:1906-1918. [PMID: 30523715 PMCID: PMC6775587 DOI: 10.1177/0271678x18817282] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Triggering receptor expressed on myeloid cells-2 (TREM2) is an innate immune receptor that promotes phagocytosis by myeloid cells such as microglia and macrophages. We previously showed that TREM2 deficiency worsened outcomes from experimental stroke and impeded phagocytosis. However, myeloid cells participating in stroke pathology include both brain resident microglia and circulating macrophages. We now clarify whether TREM2 on brain microglia or circulating macrophages contribute to its beneficial role in ischemic stroke by generating bone marrow (BM) chimeric mice. BM chimera mice from TREM2 knockout (KO) or wild type (Wt) mice were used as donor and recipient mice. Mice were subjected to experimental stroke, and neurological function and infarct volume were assessed. Mice with intact TREM2 in brain microglia showed better neurological recovery and reduced infarct volumes, compared with mice lacking microglial TREM2. Myeloid cell activation and numbers of phagocytes were decreased in mice lacking brain TREM2, compared with mice with intact brain TREM2. These results suggest that TREM2 expression is important for post-stroke recovery, and that TREM2 expression on brain resident microglia is more essential to this recovery, than that of circulating macrophages. These findings might suggest a new therapeutic target for cerebrovascular diseases.
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Affiliation(s)
- Kota Kurisu
- Department of Neurology, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Zhen Zheng
- Department of Neurology, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Jong Youl Kim
- Department of Neurology, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Jian Shi
- Department of Neurology, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Atsushi Kanoke
- Department of Neurosurgery, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Jialing Liu
- Department of Neurosurgery, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Christine L Hsieh
- Department of Medicine, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Midori A Yenari
- Department of Neurology, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
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16
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Wei CJ, Cui P, Li H, Lang WJ, Liu GY, Ma XF. Shared genes between Alzheimer's disease and ischemic stroke. CNS Neurosci Ther 2019; 25:855-864. [PMID: 30859738 PMCID: PMC6630005 DOI: 10.1111/cns.13117] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 02/12/2019] [Accepted: 02/13/2019] [Indexed: 02/06/2023] Open
Abstract
Aims Although converging evidence from experimental and epidemiological studies indicates Alzheimer's disease (AD) and ischemic stroke (IS) are related, the genetic basis underlying their links is less well characterized. Traditional SNP‐based genome‐wide association studies (GWAS) have failed to uncover shared susceptibility variants of AD and IS. Therefore, this study was designed to investigate whether pleiotropic genes existed between AD and IS to account for their phenotypic association, although this was not reported in previous studies. Methods Taking advantage of large‐scale GWAS summary statistics of AD (17,008 AD cases and 37,154 controls) and IS (10,307 IS cases and 19,326 controls), we performed gene‐based analysis implemented in VEGAS2 and Fisher's meta‐analysis of the set of overlapped genes of nominal significance in both diseases. Subsequently, gene expression analysis in AD‐ or IS‐associated expression datasets was conducted to explore the transcriptional alterations of pleiotropic genes identified. Results 16 AD‐IS pleiotropic genes surpassed the cutoff for Bonferroni‐corrected significance. Notably, MS4A4A and TREM2, two established AD‐susceptibility genes showed remarkable alterations in the spleens and brains afflicted by IS, respectively. Among the prioritized genes identified by virtue of literature‐based knowledge, most are immune‐relevant genes (EPHA1, MS4A4A, UBE2L3 and TREM2), implicating crucial roles of the immune system in the pathogenesis of AD and IS. Conclusions The observation that AD and IS had shared disease‐associated genes offered mechanistic insights into their common pathogenesis, predominantly involving the immune system. More importantly, our findings have important implications for future research directions, which are encouraged to verify the involvement of these candidates in AD and IS and interpret the exact molecular mechanisms of action.
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Affiliation(s)
- Chang-Juan Wei
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Pan Cui
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - He Li
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Wen-Jing Lang
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Gui-You Liu
- School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Xiao-Feng Ma
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
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17
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Xu H, Mu S, Qin W. Microglia TREM2 is required for electroacupuncture to attenuate neuroinflammation in focal cerebral ischemia/reperfusion rats. Biochem Biophys Res Commun 2018; 503:3225-3234. [PMID: 30149915 DOI: 10.1016/j.bbrc.2018.08.130] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 08/21/2018] [Indexed: 12/12/2022]
Abstract
Neuroinflammation plays a critical role in ischemic stroke pathology and could be a promising target in ischemic stroke. Triggering receptor expressed on myeloid cells 2 (TREM2) is a microglia-specific receptor in the CNS that is involved in regulating neuroinflammation in cerebral ischemia. However, the role of TREM2 in ischemic stroke is controversial. Electroacupuncture (EA) is an effective therapy for alleviating stroke-induced neuroinflammation. Here, we found that ischemic stroke induced an increased microglial TREM2 expression, and EA treatment can further promote microglial TREM2 expression following cerebral ischemia. TREM2 overexpression was observed to play a neuroprotective role by improving the neurobehavioral deficit and reducing the cerebral infarct volume 72 h after reperfusion, whereas TREM2 silencing had the opposite effects. Moreover, the effects of EA on improving stroke outcome and suppressing neuroinflammation in the brain were reversed by TREM2 silencing. Finally, TREM2 silencing also suppressed the ability of EA to regulate the PI3K/Akt and NF-κB signaling pathways. Altogether, the results show that TREM2 could be a potential target in EA treatment for attenuating inflammatory injury following cerebral ischemia/reperfusion.
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Affiliation(s)
- Hongbei Xu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China; Laboratory Research Center, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Song Mu
- Department of Anus & Intestine Surgery, The Affiliated Hospital of Guizhou Medical University, Guizhou, 550004, China
| | - Wenyi Qin
- Department of Integrated Chinese and Western Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China.
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18
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Wowk S, Fagan KJ, Ma Y, Nichol H, Colbourne F. Examining potential side effects of therapeutic hypothermia in experimental intracerebral hemorrhage. J Cereb Blood Flow Metab 2017; 37:2975-2986. [PMID: 27899766 PMCID: PMC5536807 DOI: 10.1177/0271678x16681312] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 10/27/2016] [Accepted: 10/30/2016] [Indexed: 11/16/2022]
Abstract
Studies treating intracerebral hemorrhage (ICH) with therapeutic hypothermia (TH) have shown inconsistent benefits. We hypothesized that TH's anti-inflammatory effects may be responsible as inflammatory cells are essential for removing degrading erythrocytes. Here, we subjected rats to a collagenase-induced striatal ICH followed by whole-body TH (∼33℃ for 11-72 h) or normothermia. We used X-ray fluorescence imaging to spatially quantify total and peri-hematoma iron three days post-injury. At three and seven days, we measured non-heme iron levels. Finally, hematoma volume was quantified on one, three, and seven days. In the injured hemisphere, total iron levels were elevated ( p < 0.001) with iron increasing in the peri-hematoma region ( p = 0.007). Non-heme iron increased from three to seven days (p < 0.001). TH had no effect on any measure of iron ( p ≥ 0.479). At one and three days, TH did not affect hematoma volume ( p ≥ 0.264); however, at seven days there was a four-fold increase in hematoma volume in 40% of treated animals ( p = 0.032). Thus, even when TH does not interfere with initial increases in total and non-heme iron or its containment, TH can cause re-bleeding post-treatment. This serious complication could partly account for the intermittent protection previously observed. This also raises serious concerns for clinical usage of TH for ICH.
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Affiliation(s)
- Shannon Wowk
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Kelly J Fagan
- Department of Biology, MacEwan University, Edmonton, Canada
| | - Yonglie Ma
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
| | - Helen Nichol
- Department of Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, Canada
| | - Frederick Colbourne
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
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19
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Kim JY, Kim N, Lee JE, Yenari MA. Hypothermia Identifies Dynamin as a Potential Therapeutic Target in Experimental Stroke. Ther Hypothermia Temp Manag 2017; 7:171-177. [PMID: 28665255 DOI: 10.1089/ther.2017.0005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Apoptosis is a cell death pathway that is activated in ischemic stroke. The interaction between Fas and its ligand (FasL) initiates a complex pattern of intracellular events involving the recruitment of specific adaptor proteins and the development of apoptosis. We recently reported that dynamin is increased after experimental stroke, and its inhibition improves neurological outcome. Dynamin has been shown to transport Fas from the endoplasmic reticulum to the cell surface where it can be bound by its ligand, FasL. Hypothermia has been shown to improve outcome in numerous stroke models, and this protection is associated with reduced apoptosis and Fas expression. To explore the contribution of dynamin to hypothermic neuroprotection, we subjected mice to distal middle cerebral artery occlusion (dMCAO) and applied one of two cooling paradigms: one where cooling began at the onset of dMCAO (early hypothermia) and another where cooling began 1 hour later (delayed hypothermia), compared with normothermia (Norm). Both cooling paradigms reduced numbers of apoptotic cells, as well as Fas and dynamin compared with Norm. Fas and dynamin were co-expressed in neurons. Neuronal cultures were exposed to oxygen glucose deprivation. Hypothermia decreased dynamin as well as surface expression of Fas, and this correlated to reduced cell death. The results of this study suggest that dynamin may participate in the Fas-mediated apoptotic pathway, and its reduction may be linked to hypothermic neuroprotection.
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Affiliation(s)
- Jong Youl Kim
- 1 Department of Neurology, San Francisco Veterans Affairs Medical Center, University of California , San Francisco, San Francisco, California.,2 Department of Anatomy, Yonsei University College of Medicine , Seoul, Republic of Korea
| | - Nuri Kim
- 1 Department of Neurology, San Francisco Veterans Affairs Medical Center, University of California , San Francisco, San Francisco, California
| | - Jong Eun Lee
- 2 Department of Anatomy, Yonsei University College of Medicine , Seoul, Republic of Korea.,3 BK21 Plus Project for Medical Science, Brain Research Institute, Yonsei University College of Medicine , Seoul, Republic of Korea
| | - Midori A Yenari
- 1 Department of Neurology, San Francisco Veterans Affairs Medical Center, University of California , San Francisco, San Francisco, California
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20
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Wu R, Li X, Xu P, Huang L, Cheng J, Huang X, Jiang J, Wu LJ, Tang Y. TREM2 protects against cerebral ischemia/reperfusion injury. Mol Brain 2017; 10:20. [PMID: 28592261 PMCID: PMC5461720 DOI: 10.1186/s13041-017-0296-9] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 04/20/2017] [Indexed: 01/01/2023] Open
Abstract
Although post-ischemic inflammation induced by the innate immune response is considered an essential step in the progression of cerebral ischemia injury, the role of triggering receptor expressed on myeloid cells 2 (TREM2) in the pathogenesis of ischemic stroke remains to be elucidated. Here, we found that the transcriptional and post-transcriptional levels of TREM2 were increased in cultured primary microglia after oxygen-glucose deprivation and reoxygenation and in the ischemic penumbra of the cerebral cortex after middle cerebral artery occlusion (MCAO) and reperfusion in mice. TREM2 was mainly expressed in microglia, but not in astrocytes, neurons, or oligodendrocytes in mice subjected to MCAO. Manipulating TREM2 expression levels in vitro and in vivo significantly regulated the production of pro- and anti-inflammatory mediators after ischemic stroke. TREM2 overexpression markedly suppressed the inflammatory response and neuronal apoptosis. By contrast, TREM2 gene silencing intensified the inflammatory response, increased neuronal apoptosis and infarct volume, and further exacerbated neurological dysfunction. Our study demonstrated that TREM2 protects against cerebral ischemia/reperfusion injury through the aspect of post-ischemic inflammatory response and neuronal apoptosis. Pharmacological targeting of TREM2 to suppress the inflammatory response may provide a new approach for developing therapeutic strategies in the treatment of ischemic stroke and other cerebrovascular diseases.
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Affiliation(s)
- Rong Wu
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Number 107, Yan Jiang Xi Road, Guangzhou, Guangdong Province, 510120, China.,Key Laboratory of Malignant Tumor Gene Regulation and Target Therapy of Guangdong Higher Education Institutes, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Xiangpen Li
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Number 107, Yan Jiang Xi Road, Guangzhou, Guangdong Province, 510120, China.,Key Laboratory of Malignant Tumor Gene Regulation and Target Therapy of Guangdong Higher Education Institutes, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Pengfei Xu
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Number 107, Yan Jiang Xi Road, Guangzhou, Guangdong Province, 510120, China.,Key Laboratory of Malignant Tumor Gene Regulation and Target Therapy of Guangdong Higher Education Institutes, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Likui Huang
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Number 107, Yan Jiang Xi Road, Guangzhou, Guangdong Province, 510120, China.,Key Laboratory of Malignant Tumor Gene Regulation and Target Therapy of Guangdong Higher Education Institutes, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Jinping Cheng
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Number 107, Yan Jiang Xi Road, Guangzhou, Guangdong Province, 510120, China.,Key Laboratory of Malignant Tumor Gene Regulation and Target Therapy of Guangdong Higher Education Institutes, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Xiaolong Huang
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Number 107, Yan Jiang Xi Road, Guangzhou, Guangdong Province, 510120, China.,Key Laboratory of Malignant Tumor Gene Regulation and Target Therapy of Guangdong Higher Education Institutes, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Jingru Jiang
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Number 107, Yan Jiang Xi Road, Guangzhou, Guangdong Province, 510120, China.,Key Laboratory of Malignant Tumor Gene Regulation and Target Therapy of Guangdong Higher Education Institutes, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Long-Jun Wu
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, 08854, USA.,Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Yamei Tang
- Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Number 107, Yan Jiang Xi Road, Guangzhou, Guangdong Province, 510120, China. .,Key Laboratory of Malignant Tumor Gene Regulation and Target Therapy of Guangdong Higher Education Institutes, Sun Yat-Sen University, Guangzhou, 510120, China. .,Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-Sen University, 74 Zhongshan 2nd Road, Guangzhou, 510080, China.
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21
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Kober DL, Brett TJ. TREM2-Ligand Interactions in Health and Disease. J Mol Biol 2017; 429:1607-1629. [PMID: 28432014 DOI: 10.1016/j.jmb.2017.04.004] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/06/2017] [Accepted: 04/10/2017] [Indexed: 01/04/2023]
Abstract
The protein triggering receptor expressed on myeloid cells-2 (TREM2) is an immunomodulatory receptor with a central role in myeloid cell activation and survival. In recent years, the importance of TREM2 has been highlighted by the identification of coding variants that increase risk for Alzheimer's disease and other neurodegenerative diseases. Animal studies have further shown the importance of TREM2 in neurodegenerative and other inflammatory disease models including chronic obstructive pulmonary disease, multiple sclerosis, and stroke. A mechanistic understanding of TREM2 function remains elusive, however, due in part to the absence of conclusive information regarding the identity of endogenous TREM2 ligands. While many TREM2 ligands have been proposed, their physiological role and mechanism of engagement remain to be determined. In this review, we highlight the suggested roles of TREM2 in these diseases and the recent advances in our understanding of TREM2 and discuss putative TREM2-ligand interactions and their potential roles in signaling during health and disease. We develop a model based on the TREM2 structure to explain how different TREM2 ligands might interact with the receptor and how disease risk variants may alter ligand interactions. Finally, we propose future experimental directions to establish the role and importance of these different interactions on TREM2 function.
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Affiliation(s)
- Daniel L Kober
- Molecular Microbiology and Microbial Pathogenesis Program, Washington University School of Medicine, St. Louis, MO 63110, USA; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Tom J Brett
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA.
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22
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Han J, Wang M, Ren M, Lou H. Contributions of triggering-receptor-expressed-on-myeloid-cells-2 to neurological diseases. Int J Neurosci 2016; 127:368-375. [PMID: 27871212 DOI: 10.1080/00207454.2016.1264072] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Jie Han
- Department of Pharmacology, School of Medicine, Shandong University, Jinan 250012, China
- Department of Radiation Oncology, Shandong Cancer Hospital and Institute affiliated to Shandong University, Jinan 250012, China
| | - Miaomiao Wang
- Department of Hematology, Qilu Hospital, Shandong University, Jinan 250012, China
| | - Manru Ren
- Department of Pharmacology, School of Medicine, Shandong University, Jinan 250012, China
| | - Haiyan Lou
- Department of Pharmacology, School of Medicine, Shandong University, Jinan 250012, China
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23
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Triggering receptor expressed on myeloid cells 2 (TREM2) deficiency attenuates phagocytic activities of microglia and exacerbates ischemic damage in experimental stroke. J Neurosci 2015; 35:3384-96. [PMID: 25716838 DOI: 10.1523/jneurosci.2620-14.2015] [Citation(s) in RCA: 246] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Clearing cellular debris after brain injury represents an important mechanism in regaining tissue homeostasis and promoting functional recovery. Triggering receptor expressed on myeloid cells-2 (TREM2) is a newly identified receptor expressed on microglia and is thought to phagocytose damaged brain cells. The precise role of TREM2 during ischemic stroke has not been fully understood. We explore TREM2 in both in vitro and in vivo stroke models and identify a potential endogenous TREM2 ligand. TREM2 knockdown in microglia reduced microglial activation to an amoeboid phenotype and decreased the phagocytosis of injured neurons. Phagocytosis and infarcted brain tissue resorption was reduced in TREM2 knock-out (KO) mice compared with wild-type (WT) mice. TREM2 KO mice also had worsened neurological recovery and decreased viable brain tissue in the ipsilateral hemisphere. The numbers of activated microglia and phagocytes in TREM2 KO mice were decreased compared with WT mice, and foamy macrophages were nearly absent in the TREM2 KO mice. Postischemia, TREM2 was highly expressed on microglia and TREM2-Fc fusion protein (used as a probe to identify potential TREM2 binding partners) bound to an unknown TREM2 ligand that colocalized to neurons. Oxygen glucose deprivation-exposed neuronal media, or cellular fractions containing nuclei or purified DNA, but not cytosolic fractions, stimulated signaling through TREM2. TREM2-Fc fusion protein pulled down nucleic acids from ischemic brain lysate. These findings establish the relevance of TREM2 in the phagocytosis of the infarcted brain and emphasize its role in influencing neurological outcomes following stroke. Further, nucleic acids may be one potential ligand of TREM2 in brain ischemia.
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Abstract
Microglia are considered the brain's resident immune cell involved in immune defense, immunocompetence, and phagocytosis. They maintain tissue homeostasis within the brain and spinal cord under normal condition and serves as its initial host defense system. However, when the central nervous system (CNS) faces injury, microglia respond through signaling molecules expressed or released by neighboring cells. Microglial responses are dual in nature. They induce a nonspecific immune response that may exacerbate CNS injury, especially in the acute stages, but are also essential to CNS recovery and repair. The full range of microglial mechanisms have yet to be clarified, but there is accumulating knowledge about microglial activation in acute CNS injury. Microglial responses require hours to days to fully develop, and may present a therapeutic target for intervention with a much longer window of opportunity compare to other neurological treatments. The challenge will be to find ways to selectively suppress the deleterious effects of microglial activation without compromising its beneficial functions. This review aims to provide an overview of the recent progress relating on the deleterious and beneficial effect of microglia in the setting of acute CNS injury and the potential therapeutic intervention against microglial activation to CNS injury.
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Affiliation(s)
- Masahito Kawabori
- Department of Neurology, University of California, San Francisco and the San Francisco Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121, USA
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25
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Dietrichs ES, Dietrichs E. Nevroprotektiv effekt av hypotermi. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 2015; 135:1646-51. [DOI: 10.4045/tidsskr.14.1250] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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26
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Kim JY, Kim N, Yenari MA. Mechanisms and potential therapeutic applications of microglial activation after brain injury. CNS Neurosci Ther 2014; 21:309-19. [PMID: 25475659 DOI: 10.1111/cns.12360] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 10/24/2014] [Accepted: 10/26/2014] [Indexed: 12/14/2022] Open
Abstract
As the resident immune cells of the central nervous system, microglia rapidly respond to brain insults, including stroke and traumatic brain injury. Microglial activation plays a major role in neuronal cell damage and death by releasing a variety of inflammatory and neurotoxic mediators. Their activation is an early response that may exacerbate brain injury and many other stressors, especially in the acute stages, but are also essential to brain recovery and repair. The full range of microglial activities is still not completely understood, but there is accumulating knowledge about their role following brain injury. We review recent progress related to the deleterious and beneficial effects of microglia in the setting of acute neurological insults and the current literature surrounding pharmacological interventions for intervention.
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Affiliation(s)
- Jong-Youl Kim
- Department of Neurology, San Francisco Veterans Affairs Medical Center, University of California, San Francisco, San Francisco, CA, USA
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27
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Bhattacharjee S, Zhao Y, Lukiw WJ. Deficits in the miRNA-34a-regulated endogenous TREM2 phagocytosis sensor-receptor in Alzheimer's disease (AD); an update. Front Aging Neurosci 2014; 6:116. [PMID: 24987367 PMCID: PMC4060025 DOI: 10.3389/fnagi.2014.00116] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Accepted: 05/24/2014] [Indexed: 01/22/2023] Open
Affiliation(s)
- Surjyadipta Bhattacharjee
- Departments of Neurology, Neuroscience and Ophthalmology, Louisiana State University Neuroscience Center and Health Sciences Center New Orleans, LA, USA
| | - Yuhai Zhao
- Departments of Neurology, Neuroscience and Ophthalmology, Louisiana State University Neuroscience Center and Health Sciences Center New Orleans, LA, USA
| | - Walter J Lukiw
- Departments of Neurology, Neuroscience and Ophthalmology, Louisiana State University Neuroscience Center and Health Sciences Center New Orleans, LA, USA
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