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Yin W, Ma H, Qu Y, Ren J, Sun Y, Guo ZN, Yang Y. Exosomes: the next-generation therapeutic platform for ischemic stroke. Neural Regen Res 2025; 20:1221-1235. [PMID: 39075892 DOI: 10.4103/nrr.nrr-d-23-02051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 03/19/2024] [Indexed: 07/31/2024] Open
Abstract
Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional recovery. Therefore, there is an urgent need to develop new methods for the treatment of this condition. Exosomes are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological conditions. They have low immunogenicity, good stability, high delivery efficiency, and the ability to cross the blood-brain barrier. These physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic stroke. The rapid development of nanotechnology has advanced the application of engineered exosomes, which can effectively improve targeting ability, enhance therapeutic efficacy, and minimize the dosages needed. Advances in technology have also driven clinical translational research on exosomes. In this review, we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke, including their anti-inflammation, anti-apoptosis, autophagy-regulation, angiogenesis, neurogenesis, and glial scar formation reduction effects. However, it is worth noting that, despite their significant therapeutic potential, there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified exosomes. Future optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic stroke. Ultimately, our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.
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Affiliation(s)
- Wenjing Yin
- Stroke Center, Department of Neurology, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Hongyin Ma
- Stroke Center, Department of Neurology, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Yang Qu
- Stroke Center, Department of Neurology, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Jiaxin Ren
- Stroke Center, Department of Neurology, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Yingying Sun
- Stroke Center, Department of Neurology, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Zhen-Ni Guo
- Stroke Center, Department of Neurology, First Hospital of Jilin University, Changchun, Jilin Province, China
- Neuroscience Research Center, Department of Neurology, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Yi Yang
- Stroke Center, Department of Neurology, First Hospital of Jilin University, Changchun, Jilin Province, China
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Dong R, Liu W, Han Y, Wang Z, Jiang L, Wang L, Gu X. Influencing factors of glymphatic system during perioperative period. Front Neurosci 2024; 18:1428085. [PMID: 39328423 PMCID: PMC11424614 DOI: 10.3389/fnins.2024.1428085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Accepted: 08/23/2024] [Indexed: 09/28/2024] Open
Abstract
The glymphatic system is a functional cerebrospinal fluid circulatory system that uses peri-arterial space for inflow of cerebrospinal fluid and peri-venous space for efflux of cerebrospinal fluid from brain parenchyma. This brain-wide fluid transport pathway facilitates the exchange between cerebrospinal fluid and interstitial fluid and clears metabolic waste from the metabolically active brain. Multiple lines of work show that the glymphatic system is crucial to normal brain functions, and the dysfunction of the glymphatic system is closely associated with various neurological disorders, including aging, neurodegeneration, and acute brain injury. Currently, it is common to explore the functional and molecular mechanisms of the glymphatic system based on animal models. The function of glymphatic system during perioperative period is affected by many factors such as physiological, pathological, anesthetic and operative methods. To provide a reference for the interpretation of the results of glymphatic system studies during perioperative period, this article comprehensively reviews the physiological and pathological factors that interfere with the function of the glymphatic system during perioperative period, investigates the effects of anesthetic drugs on glymphatic system function and the potential underlying mechanisms, describes operative methods that interfere with the function of the glymphatic system, and potential intervention strategies based on the glymphatic system. Future, these variables should be taken into account as critical covariates in the design of functional studies on the glymphatic system.
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Affiliation(s)
- Rui Dong
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
- Department of Anesthesiology, Qingdao Municipal Hospital, Qingdao, China
- Key Laboratory of Anesthesiology and Resuscitation, Ministry of Education, Huazhong University of Science and Technology, Wuhan, China
| | - Wenjie Liu
- Department of Anesthesiology, Qingdao Municipal Hospital, Qingdao, China
| | - Yuqiang Han
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Zimo Wang
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Linhao Jiang
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Liwei Wang
- Department of Anesthesiology, Xuzhou Central Hospital, Xuzhou, China
| | - Xiaoping Gu
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
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Ryou MG, Burton S. Intermittent hypoxic training - derived exosomes in stroke rehabilitation. Front Integr Neurosci 2024; 18:1475234. [PMID: 39323911 PMCID: PMC11422222 DOI: 10.3389/fnint.2024.1475234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2024] [Accepted: 08/19/2024] [Indexed: 09/27/2024] Open
Abstract
Ischemic stroke is the fourth leading cause of adult disability in the US, and it is a huge social burden all over the world. However, the efficient treatment of ischemic stroke is not available. An apparent reason for failing to find or develop an intervention for ischemic stroke is contributed to the tight blood-brain barrier (BBB). The unique characteristics of exosomes that can traverse BBB have been highlighted among researchers investigating interventions for ischemic stroke conditions. Additionally, intermittent hypoxic training has been considered a potential intervention in the treatment or rehabilitation process of ischemic stroke patients. In this mini-review, we are going to review the possibility of applying exosomes produced by a subject who does intermittent hypoxic conditioning in a treatment program for ischemic stroke.
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Affiliation(s)
- Myoung-Gwi Ryou
- Department of Medical Laboratory Sciences, Public Health, and Nutrition Science, College of Health Science, Tarleton State University, Fort Worth, TX, United States
| | - Summer Burton
- Department of Medical Laboratory Sciences, Public Health, and Nutrition Science, College of Health Science, Tarleton State University, Fort Worth, TX, United States
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Yang J, Cao C, Liu J, Liu Y, Lu J, Yu H, Li X, Wu J, Yu Z, Li H, Chen G. Dystrophin 71 deficiency causes impaired aquaporin-4 polarization contributing to glymphatic dysfunction and brain edema in cerebral ischemia. Neurobiol Dis 2024; 199:106586. [PMID: 38950712 DOI: 10.1016/j.nbd.2024.106586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 06/28/2024] [Accepted: 06/28/2024] [Indexed: 07/03/2024] Open
Abstract
OBJECTIVE The glymphatic system serves as a perivascular pathway that aids in clearing liquid and solute waste from the brain, thereby enhancing neurological function. Disorders in glymphatic drainage contribute to the development of vasogenic edema following cerebral ischemia, although the molecular mechanisms involved remain poorly understood. This study aims to determine whether a deficiency in dystrophin 71 (DP71) leads to aquaporin-4 (AQP4) depolarization, contributing to glymphatic dysfunction in cerebral ischemia and resulting in brain edema. METHODS A mice model of middle cerebral artery occlusion and reperfusion was used. A fluorescence tracer was injected into the cortex and evaluated glymphatic clearance. To investigate the role of DP71 in maintaining AQP4 polarization, an adeno-associated virus with the astrocyte promoter was used to overexpress Dp71. The expression and distribution of DP71 and AQP4 were analyzed using immunoblotting, immunofluorescence, and co-immunoprecipitation techniques. The behavior ability of mice was evaluated by open field test. Open-access transcriptome sequencing data were used to analyze the functional changes of astrocytes after cerebral ischemia. MG132 was used to inhibit the ubiquitin-proteasome system. The ubiquitination of DP71 was detected by immunoblotting and co-immunoprecipitation. RESULTS During the vasogenic edema stage following cerebral ischemia, a decline in the efflux of interstitial fluid tracer was observed. DP71 and AQP4 were co-localized and interacted with each other in the perivascular astrocyte endfeet. After cerebral ischemia, there was a notable reduction in DP71 protein expression, accompanied by AQP4 depolarization and proliferation of reactive astrocytes. Increased DP71 expression restored glymphatic drainage and reduced brain edema. AQP4 depolarization, reactive astrocyte proliferation, and the behavior of mice were improved. After cerebral ischemia, DP71 was degraded by ubiquitination, and MG132 inhibited the decrease of DP71 protein level. CONCLUSION AQP4 depolarization after cerebral ischemia leads to glymphatic clearance disorder and aggravates cerebral edema. DP71 plays a pivotal role in regulating AQP4 polarization and consequently influences glymphatic function. Changes in DP71 expression are associated with the ubiquitin-proteasome system. This study offers a novel perspective on the pathogenesis of brain edema following cerebral ischemia.
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Affiliation(s)
- Jian Yang
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China
| | - Chang Cao
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China
| | - Jiale Liu
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China
| | - Yangyang Liu
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China
| | - Jinxin Lu
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China
| | - HaoYun Yu
- Suzhou Medical College, Soochow University, Suzhou, Jiangsu Province, China
| | - Xiang Li
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China
| | - Jiang Wu
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China.
| | - Zhengquan Yu
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China.
| | - Haiying Li
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China.
| | - Gang Chen
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province, China
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Mo S, Yang C, Zheng X, Lv H, Mao S, Liu N, Yang Q, Liao B, Yang M, Lu Z, Tang L, Huang X, Jian C, Li X, Shang J. Neuroprotective Effects of AER-271 in a tMCAO Mouse Model: Modulation of Autophagy, Apoptosis, and Inflammation. Inflammation 2024:10.1007/s10753-024-02082-7. [PMID: 39117789 DOI: 10.1007/s10753-024-02082-7] [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: 02/12/2024] [Revised: 06/10/2024] [Accepted: 06/12/2024] [Indexed: 08/10/2024]
Abstract
Following ischemic stroke, aquaporin 4 (AQP4) expression modifications have been associated with increased inflammation. However, the underlying mechanisms are not fully understood. This study aims to elucidate the mechanistic basis of post-cerebral ischemia-reperfusion (I/R) inflammation by employing the AQP4-specific inhibitor, AER-271. The middle cerebral artery occlusion (MCAO) model was used to induce ischemic stroke in mice. C57BL/6 mice were randomly allocated into four groups: sham operation, I/R, AER-271, and 2-(nicotinamide)-1,3,4-thiadiazole (TGN-020) treatment, with observations recorded at 1 day, 3 days, and 7 days post-tMCAO. Each group consisted of 15 mice. Procedures included histological examination through HE staining, neurological scoring, Western blot analysis, and immunofluorescence staining. AER-271 treatment yielded significant improvements in post-stroke weight recovery and neurological scores, accompanied by a reduction in cerebral infarction volume. Moreover, AER-271 exhibited a noticeable influence on autophagic and apoptotic pathways, affecting the activation of both pro-inflammatory and anti-inflammatory cytokines. Alterations in the levels of inflammatory biomarkers MCP-1, NLRP3, and caspase 1 were also detected. Finally, a comparative assessment of the effects of AER-271 and TGN-020 in mitigating apoptosis and microglial polarization in ischemic mice revealed neuroprotective effects with no significant difference in efficacy. This study provides essential insights into the neuroprotective mechanisms of AER-271 in cerebral ischemia-reperfusion injury, offering potential clinical applications in the treatment of ischemic cerebrovascular disorders.
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Affiliation(s)
- Shenglong Mo
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, 533000, Guangxi, China
- Biological Molecule Laboratory, Guangxi University Key Laboratory of High Incidence Prevention and Control Research in Western Guangxi, Baise, 53300, Guangxi, China
- Graduate School of Youjiang, Medical University for Nationalities, Baise, Guangxi, China
| | - Chengmin Yang
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, 533000, Guangxi, China
- Biological Molecule Laboratory, Guangxi University Key Laboratory of High Incidence Prevention and Control Research in Western Guangxi, Baise, 53300, Guangxi, China
| | - Xingwu Zheng
- Department of Geriatrics, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China
| | - Hui Lv
- Modern Industrial College of Biomedicine and Great Health, Youjiang Medical University for Nationalities, Baise, Guangxi, China
| | - Sanyin Mao
- Department of Neurology, The First People's Hospital of Jiande, Hangzhou, China
| | - Ning Liu
- School of Basic Medical Sciences, Beihua University, Jilin, China
| | - Qin Yang
- Department of Neurology, BAISE PEOPLE'S HOSPITAL, Baise, Guangxi, China
| | - Bao Liao
- Department of Neurology, BAISE PEOPLE'S HOSPITAL, Baise, Guangxi, China
| | - Meiling Yang
- Graduate School of Youjiang, Medical University for Nationalities, Baise, Guangxi, China
| | - Zhicheng Lu
- Graduate School of Youjiang, Medical University for Nationalities, Baise, Guangxi, China
| | - Lina Tang
- Graduate School of Youjiang, Medical University for Nationalities, Baise, Guangxi, China
| | - Xiaorui Huang
- Department of Psychiatry and Psychology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China
| | - Chongdong Jian
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, 533000, Guangxi, China.
- Biological Molecule Laboratory, Guangxi University Key Laboratory of High Incidence Prevention and Control Research in Western Guangxi, Baise, 53300, Guangxi, China.
| | - Xuebin Li
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, 533000, Guangxi, China.
- Biological Molecule Laboratory, Guangxi University Key Laboratory of High Incidence Prevention and Control Research in Western Guangxi, Baise, 53300, Guangxi, China.
| | - Jingwei Shang
- Department of Neurology, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, 533000, Guangxi, China.
- Biological Molecule Laboratory, Guangxi University Key Laboratory of High Incidence Prevention and Control Research in Western Guangxi, Baise, 53300, Guangxi, China.
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Cui C, Jiang X, Wang Y, Li C, Lin Z, Wei Y, Ni Q. Cerebral Hypoxia-Induced Molecular Alterations and Their Impact on the Physiology of Neurons and Dendritic Spines: A Comprehensive Review. Cell Mol Neurobiol 2024; 44:58. [PMID: 39105862 PMCID: PMC11303443 DOI: 10.1007/s10571-024-01491-4] [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: 05/28/2024] [Accepted: 07/15/2024] [Indexed: 08/07/2024]
Abstract
This article comprehensively reviews how cerebral hypoxia impacts the physiological state of neurons and dendritic spines through a series of molecular changes, and explores the causal relationship between these changes and neuronal functional impairment. As a severe pathological condition, cerebral hypoxia can significantly alter the morphology and function of neurons and dendritic spines. Specifically, dendritic spines, being the critical structures for neurons to receive information, undergo changes such as a reduction in number and morphological abnormalities under hypoxic conditions. These alterations further affect synaptic function, leading to neurotransmission disorders. This article delves into the roles of molecular pathways like MAPK, AMPA receptors, NMDA receptors, and BDNF in the hypoxia-induced changes in neurons and dendritic spines, and outlines current treatment strategies. Neurons are particularly sensitive to cerebral hypoxia, with their apical dendrites being vulnerable to damage, thereby affecting cognitive function. Additionally, astrocytes and microglia play an indispensable role in protecting neuronal and synaptic structures, regulating their normal functions, and contributing to the repair process following injury. These studies not only contribute to understanding the pathogenesis of related neurological diseases but also provide important insights for developing novel therapeutic strategies. Future research should further focus on the dynamic changes in neurons and dendritic spines under hypoxic conditions and their intrinsic connections with cognitive function.
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Affiliation(s)
- Chao Cui
- Hydrogen Medical Research Center, The Affiliated Taian City Central Hospital of Qingdao University, Taian, 271000, Shandong, China
| | - Xue Jiang
- Hydrogen Medical Research Center, The Affiliated Taian City Central Hospital of Qingdao University, Taian, 271000, Shandong, China
| | - Yumei Wang
- Hydrogen Medical Research Center, The Affiliated Taian City Central Hospital of Qingdao University, Taian, 271000, Shandong, China
| | - Chao Li
- Hydrogen Medical Research Center, The Affiliated Taian City Central Hospital of Qingdao University, Taian, 271000, Shandong, China
| | - Zhaochen Lin
- Hydrogen Medical Research Center, The Affiliated Taian City Central Hospital of Qingdao University, Taian, 271000, Shandong, China
| | - Youzhen Wei
- Hydrogen Medical Research Center, The Affiliated Taian City Central Hospital of Qingdao University, Taian, 271000, Shandong, China.
- Research Center for Translational Medicine & Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200000, China.
| | - Qingbin Ni
- Hydrogen Medical Research Center, The Affiliated Taian City Central Hospital of Qingdao University, Taian, 271000, Shandong, China.
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He Y, Fan Y, Ahmadpoor X, Wang Y, Li ZA, Zhu W, Lin H. Targeting lysosomal quality control as a therapeutic strategy against aging and diseases. Med Res Rev 2024. [PMID: 38711187 DOI: 10.1002/med.22047] [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: 08/19/2023] [Revised: 04/04/2024] [Accepted: 04/21/2024] [Indexed: 05/08/2024]
Abstract
Previously, lysosomes were primarily referred to as the digestive organelles and recycling centers within cells. Recent discoveries have expanded the lysosomal functional scope and revealed their critical roles in nutrient sensing, epigenetic regulation, plasma membrane repair, lipid transport, ion homeostasis, and cellular stress response. Lysosomal dysfunction is also found to be associated with aging and several diseases. Therefore, function of macroautophagy, a lysosome-dependent intracellular degradation system, has been identified as one of the updated twelve hallmarks of aging. In this review, we begin by introducing the concept of lysosomal quality control (LQC), which is a cellular machinery that maintains the number, morphology, and function of lysosomes through different processes such as lysosomal biogenesis, reformation, fission, fusion, turnover, lysophagy, exocytosis, and membrane permeabilization and repair. Next, we summarize the results from studies reporting the association between LQC dysregulation and aging/various disorders. Subsequently, we explore the emerging therapeutic strategies that target distinct aspects of LQC for treating diseases and combatting aging. Lastly, we underscore the existing knowledge gap and propose potential avenues for future research.
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Affiliation(s)
- Yuchen He
- Department of Orthopaedics, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Yishu Fan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xenab Ahmadpoor
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Yumin Wang
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zhong Alan Li
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
- Center for Neuromusculoskeletal Restorative Medicine, Hong Kong Science Park, Shatin, NT, Hong Kong SAR, China
| | - Weihong Zhu
- Department of Orthopaedics, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Department of Orthopaedic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Hang Lin
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Bioengineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, Pennsylvania, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Pan Y, Xin W, Wei W, Tatenhorst L, Graf I, Popa-Wagner A, Gerner ST, Huber SE, Kilic E, Hermann DM, Bähr M, Huttner HB, Doeppner TR. Knockdown of NEAT1 prevents post-stroke lipid droplet agglomeration in microglia by regulating autophagy. Cell Mol Life Sci 2024; 81:30. [PMID: 38212456 PMCID: PMC10784396 DOI: 10.1007/s00018-023-05045-7] [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: 09/06/2023] [Revised: 11/06/2023] [Accepted: 11/09/2023] [Indexed: 01/13/2024]
Abstract
BACKGROUND Lipid droplets (LD), lipid-storing organelles containing neutral lipids like glycerolipids and cholesterol, are increasingly accepted as hallmarks of inflammation. The nuclear paraspeckle assembly transcript 1 (NEAT1), a long non-coding RNA with over 200 nucleotides, exerts an indispensable impact on regulating both LD agglomeration and autophagy in multiple neurological disorders. However, knowledge as to how NEAT1 modulates the formation of LD and associated signaling pathways is limited. METHODS In this study, primary microglia were isolated from newborn mice and exposed to oxygen-glucose-deprivation/reoxygenation (OGD/R). To further explore NEAT1-dependent mechanisms, an antisense oligonucleotide (ASO) was adopted to silence NEAT1 under in vitro conditions. Studying NEAT1-dependent interactions with regard to autophagy and LD agglomeration under hypoxic conditions, the inhibitor and activator of autophagy 3-methyladenine (3-MA) and rapamycin (RAPA) were used, respectively. In a preclinical stroke model, mice received intraventricular injections of ASO NEAT1 or control vectors in order to yield NEAT1 knockdown. Analysis of readout parameters included qRT-PCR, immunofluorescence, western blot assays, and behavioral tests. RESULTS Microglia exposed to OGD/R displayed a temporal pattern of NEAT1 expression, peaking at four hours of hypoxia followed by six hours of reoxygenation. After effectively silencing NEAT1, LD formation and autophagy-related proteins were significantly repressed in hypoxic microglia. Stimulating autophagy in ASO NEAT1 microglia under OGD/R conditions by means of RAPA reversed the downregulation of LD agglomeration and perilipin 2 (PLIN2) expression. On the contrary, application of 3-MA promoted repression of both LD agglomeration and expression of the LD-associated protein PLIN2. Under in vivo conditions, NEAT1 was significantly increased in mice at 24 h post-stroke. Knockdown of NEAT1 significantly alleviated LD agglomeration and inhibited autophagy, resulting in improved cerebral perfusion, reduced brain injury and increased neurological recovery. CONCLUSION NEAT1 is a key player of LD agglomeration and autophagy stimulation, and NEAT1 knockdown provides a promising therapeutic value against stroke.
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Affiliation(s)
- Yongli Pan
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Wenqiang Xin
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Wei Wei
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Lars Tatenhorst
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Irina Graf
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Aurel Popa-Wagner
- Department of Neurology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Stefan T Gerner
- Department of Neurology, University of Giessen Medical School, Giessen, Germany
| | - Sabine E Huber
- Department of Neurology, University of Giessen Medical School, Giessen, Germany
| | - Ertugrul Kilic
- Department of Physiology, Faculty of Medicine, Istanbul Medeniyet University, Istanbul, Turkey
| | - Dirk M Hermann
- Department of Neurology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Mathias Bähr
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Hagen B Huttner
- Department of Neurology, University of Giessen Medical School, Giessen, Germany
| | - Thorsten R Doeppner
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany.
- Department of Neurology, University of Giessen Medical School, Giessen, Germany.
- Department of Anatomy and Cell Biology, Medical University of Varna, Varna, Bulgaria.
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Giessen, Germany.
- Research Institute for Health Sciences and Technologies (SABITA), Medipol University, Istanbul, Turkey.
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Wei W, Zhang L, Xin W, Pan Y, Tatenhorst L, Hao Z, Gerner ST, Huber S, Juenemann M, Butz M, Huttner HB, Bähr M, Fitzner D, Jia F, Doeppner TR. TREM2 regulates microglial lipid droplet formation and represses post-ischemic brain injury. Biomed Pharmacother 2024; 170:115962. [PMID: 38042110 DOI: 10.1016/j.biopha.2023.115962] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/14/2023] [Accepted: 11/27/2023] [Indexed: 12/04/2023] Open
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2) is a transmembrane receptor protein predominantly expressed in microglia within the central nervous system (CNS). TREM2 regulates multiple microglial functions, including lipid metabolism, immune reaction, inflammation, and microglial phagocytosis. Recent studies have found that TREM2 is highly expressed in activated microglia after ischemic stroke. However, the role of TREM2 in the pathologic response after stroke remains unclear. Herein, TREM2-deficient microglia exhibit an impaired phagocytosis rate and cholesteryl ester (CE) accumulation, leading to lipid droplet formation and upregulation of Perilipin-2 (PLIN2) expression after hypoxia. Knockdown of TREM2 results in increased lipid synthesis (PLIN2, SOAT1) and decreased cholesterol clearance and lipid hydrolysis (LIPA, ApoE, ABCA1, NECH1, and NPC2), further impacting microglial phenotypes. In these lipid droplet-rich microglia, the TGF-β1/Smad2/3 signaling pathway is downregulated, driving microglia towards a pro-inflammatory phenotype. Meanwhile, in a neuron-microglia co-culture system under hypoxic conditions, we found that microglia lost their protective effect against neuronal injury and apoptosis when TREM2 was knocked down. Under in vivo conditions, TREM2 knockdown mice express lower TGF-β1 expression levels and a lower number of anti-inflammatory M2 phenotype microglia, resulting in increased cerebral infarct size, exacerbated neuronal apoptosis, and aggravated neuronal impairment. Our work suggests that TREM2 attenuates stroke-induced neuroinflammation by modulating the TGF-β1/Smad2/3 signaling pathway. TREM2 may play a direct role in the regulation of inflammation and also exert an influence on the post-ischemic inflammation and the stroke pathology progression via regulation of lipid metabolism processes. Thus, underscoring the therapeutic potential of TREM2 agonists in ischemic stroke and making TREM2 an attractive new clinical target for the treatment of ischemic stroke and other inflammation-related diseases.
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Affiliation(s)
- Wei Wei
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Lin Zhang
- Department of Neurosurgery, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wenqiang Xin
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Yongli Pan
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Lars Tatenhorst
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Zhongnan Hao
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Stefan T Gerner
- Department of Neurology, University of Giessen Medical School, Giessen, Germany
| | - Sabine Huber
- Department of Neurology, University of Giessen Medical School, Giessen, Germany
| | - Martin Juenemann
- Department of Neurology, University of Giessen Medical School, Giessen, Germany
| | - Marius Butz
- Heart and Brain Research Group, Kerckhoff Heart and Thorax Center, Bad Nauheim, Germany
| | - Hagen B Huttner
- Department of Neurology, University of Giessen Medical School, Giessen, Germany
| | - Mathias Bähr
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Dirk Fitzner
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany.
| | - Feng Jia
- Department of Neurosurgery, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Neurosurgery, Nantong First People's Hospital, Affiliated Hospital 2 of Nantong University, Nantong, China.
| | - Thorsten R Doeppner
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany; Department of Neurology, University of Giessen Medical School, Giessen, Germany; Department of Anatomy and Cell Biology, Medical University of Varna, Varna, Bulgaria; Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Giessen, Germany; Research Institute for Health Sciences and Technologies (SABITA), Medipol University, Istanbul, Turkey.
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Xin W, Pan Y, Wei W, Gerner ST, Huber S, Juenemann M, Butz M, Bähr M, Huttner HB, Doeppner TR. TGF-β1 Decreases Microglia-Mediated Neuroinflammation and Lipid Droplet Accumulation in an In Vitro Stroke Model. Int J Mol Sci 2023; 24:17329. [PMID: 38139158 PMCID: PMC10743979 DOI: 10.3390/ijms242417329] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/05/2023] [Accepted: 12/08/2023] [Indexed: 12/24/2023] Open
Abstract
Hypoxia triggers reactive microglial inflammation and lipid droplet (LD) accumulation under stroke conditions, although the mutual interactions between these two processes are insufficiently understood. Hence, the involvement of transforming growth factor (TGF)-β1 in inflammation and LD accumulation in cultured microglia exposed to hypoxia were analyzed herein. Primary microglia were exposed to oxygen-glucose deprivation (OGD) injury and lipopolysaccharide (LPS) stimulation. For analyzing the role of TGF-β1 patterns under such conditions, a TGF-β1 siRNA and an exogenous recombinant TGF-β1 protein were employed. Further studies applied Triacsin C, an inhibitor of LD formation, in order to directly assess the impact of LD formation on the modulation of inflammation. To assess mutual microglia-to-neuron interactions, a co-culture model of these cells was established. Upon OGD exposure, microglial TGF-β1 levels were significantly increased, whereas LPS stimulation yielded decreased levels. Elevating TGF-β1 expression proved highly effective in suppressing inflammation and reducing LD accumulation in microglia exposed to LPS. Conversely, inhibition of TGF-β1 led to the promotion of microglial cell inflammation and an increase in LD accumulation in microglia exposed to OGD. Employing the LD formation inhibitor Triacsin C, in turn, polarized microglia towards an anti-inflammatory phenotype. Such modulation of both microglial TGF-β1 and LD levels significantly affected the resistance of co-cultured neurons. This study provides novel insights by demonstrating that TGF-β1 plays a protective role against microglia-mediated neuroinflammation through the suppression of LD accumulation. These findings offer a fresh perspective on stroke treatment, suggesting the potential of targeting this pathway for therapeutic interventions.
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Affiliation(s)
- Wenqiang Xin
- Department of Neurology, University of Göttingen Medical School, 37075 Goettingen, Germany; (W.X.); (Y.P.); (W.W.); (M.B.)
| | - Yongli Pan
- Department of Neurology, University of Göttingen Medical School, 37075 Goettingen, Germany; (W.X.); (Y.P.); (W.W.); (M.B.)
| | - Wei Wei
- Department of Neurology, University of Göttingen Medical School, 37075 Goettingen, Germany; (W.X.); (Y.P.); (W.W.); (M.B.)
| | - Stefan T. Gerner
- Department of Neurology, University of Giessen Medical School, 35392 Giessen, Germany; (S.T.G.); (M.J.); (M.B.); (H.B.H.)
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University, 35032 Giessen, Germany
| | - Sabine Huber
- Department of Neurology, University of Giessen Medical School, 35392 Giessen, Germany; (S.T.G.); (M.J.); (M.B.); (H.B.H.)
| | - Martin Juenemann
- Department of Neurology, University of Giessen Medical School, 35392 Giessen, Germany; (S.T.G.); (M.J.); (M.B.); (H.B.H.)
| | - Marius Butz
- Department of Neurology, University of Giessen Medical School, 35392 Giessen, Germany; (S.T.G.); (M.J.); (M.B.); (H.B.H.)
- Heart and Brain Research Group, Kerckhoff Heart and Thorax Center, 61231 Bad Nauheim, Germany
| | - Mathias Bähr
- Department of Neurology, University of Göttingen Medical School, 37075 Goettingen, Germany; (W.X.); (Y.P.); (W.W.); (M.B.)
| | - Hagen B. Huttner
- Department of Neurology, University of Giessen Medical School, 35392 Giessen, Germany; (S.T.G.); (M.J.); (M.B.); (H.B.H.)
| | - Thorsten R. Doeppner
- Department of Neurology, University of Göttingen Medical School, 37075 Goettingen, Germany; (W.X.); (Y.P.); (W.W.); (M.B.)
- Department of Neurology, University of Giessen Medical School, 35392 Giessen, Germany; (S.T.G.); (M.J.); (M.B.); (H.B.H.)
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University, 35032 Giessen, Germany
- Department of Anatomy and Cell Biology, Medical University of Varna, 9238 Varna, Bulgaria
- Research Institute for Health Sciences and Technologies (SABITA), Medipol University, 100098 Istanbul, Turkey
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