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Li P, Tao Z, Zhao X. The Role of Osteopontin (OPN) in Regulating Microglia Phagocytosis in Nervous System Diseases. J Integr Neurosci 2024; 23:169. [PMID: 39344228 DOI: 10.31083/j.jin2309169] [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: 03/23/2024] [Revised: 05/09/2024] [Accepted: 05/29/2024] [Indexed: 10/01/2024] Open
Abstract
Phagocytosis is the process by which certain cells or organelles internalise foreign substances by engulfing them and then digesting or disposing of them. Microglia are the main resident phagocytic cells in the brain. It is generally believed that microglia/macrophages play a role in guiding the brain's repair and functional recovery processes. However, the resident and invading immune cells of the central nervous system can also exacerbate tissue damage by stimulating inflammation and engulfing viable neurons. The functional consequences of microglial phagocytosis remain largely unexplored. Overall, phagocytosis is considered a beneficial phenomenon in acute brain injury because it eliminates dead cells and induces an anti-inflammatory response. Osteopontin (OPN) is a phosphorylated glycoprotein induced by injury in various tissues, including brain tissue. In acute brain injuries such as hemorrhagic stroke and ischemic stroke, OPN is generally believed to have anti-inflammatory effects. OPN can promote the reconstruction of the blood-brain barrier and up-regulate the scavenger receptor CD36. But in chronic diseases such as Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS), OPN can cause microglia to engulf neurons and worsen disease progression. We explored the role of OPN in promoting microglial phagocytosis in nervous system disorders.
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Affiliation(s)
- Pengpeng Li
- Wuxi School of Medicine, Jiangnan University, 214122 Wuxi, Jiangsu, China
- Department of Neurosurgery, Jiangnan University Medical Center, 214005 Wuxi, Jiangsu, China
| | - Zhengxin Tao
- Wuxi School of Medicine, Jiangnan University, 214122 Wuxi, Jiangsu, China
- Department of Neurosurgery, Jiangnan University Medical Center, 214005 Wuxi, Jiangsu, China
| | - Xudong Zhao
- Department of Neurosurgery, Jiangnan University Medical Center, 214005 Wuxi, Jiangsu, China
- Wuxi Neurosurgical Institute, Wuxi School of Medicine, Jiangnan University, 214002 Wuxi, Jiangsu, China
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Zuo HJ, Wang PX, Ren XQ, Shi HL, Shi JS, Guo T, Wan C, Li JJ. Gastrodin Regulates PI3K/AKT-Sirt3 Signaling Pathway and Proinflammatory Mediators in Activated Microglia. Mol Neurobiol 2024; 61:2728-2744. [PMID: 37930585 DOI: 10.1007/s12035-023-03743-8] [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: 08/01/2023] [Accepted: 10/25/2023] [Indexed: 11/07/2023]
Abstract
Activated microglia and their mediated inflammatory responses play an important role in the pathogenesis of hypoxic-ischemic brain damage (HIBD). Therefore, regulating microglia activation is considered a potential therapeutic strategy. The neuroprotective effects of gastrodin were evaluated in HIBD model mice, and in oxygen glucose deprivation (OGD)-treated and lipopolysaccharide (LPS)activated BV-2 microglia cells. The potential molecular mechanism was investigated using western blotting, immunofluorescence labeling, quantitative realtime reverse transcriptase polymerase chain reaction, and flow cytometry. Herein, we found that PI3K/AKT signaling can regulate Sirt3 in activated microglia, but not reciprocally. And gastrodin exerts anti-inflammatory and antiapoptotic effects through the PI3K/AKT-Sirt3 signaling pathway. In addition, gastrodin could promote FOXO3a phosphorylation, and inhibit ROS production in LPSactivated BV-2 microglia. Moreover, the level P-FOXO3a decreased significantly in Sirt3-siRNA group. However, there was no significant change after gastrodin and siRNA combination treatment. Notably, gastrodin might also affect the production of ROS in activated microglia by regulating the level of P-FOXO3a via Sirt3. Together, this study highlighted the neuroprotective role of PI3K/AKT-Sirt3 axis in HIBD, and the anti-inflammatory, anti-apoptotic, and anti-oxidative stress effects of gastrodin on HIBD.
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Affiliation(s)
- Han-Jun Zuo
- Department of Anatomy and Histology & Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, 1168 West Chunrong Road, Kunming, Yunnan, 650500, China
| | - Peng-Xiang Wang
- Department of Anatomy and Histology & Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, 1168 West Chunrong Road, Kunming, Yunnan, 650500, China
| | - Xue-Qi Ren
- Department of Anatomy and Histology & Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, 1168 West Chunrong Road, Kunming, Yunnan, 650500, China
| | - Hao-Long Shi
- Department of Anatomy and Histology & Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, 1168 West Chunrong Road, Kunming, Yunnan, 650500, China
| | - Jin-Sha Shi
- Department of Anatomy and Histology & Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, 1168 West Chunrong Road, Kunming, Yunnan, 650500, China
| | - Tao Guo
- Department of Anatomy and Histology & Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, 1168 West Chunrong Road, Kunming, Yunnan, 650500, China
| | - Cheng Wan
- Department of Medical Imaging, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, 650031, China
| | - Juan-Juan Li
- Department of Anatomy and Histology & Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, 1168 West Chunrong Road, Kunming, Yunnan, 650500, China.
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Sun L, Wan J, Sun B, Tian Q, Li M, Xu LX, Feng CX, Tong X, Feng X, Yang X, Ding X. LncRNA-mir3471-limd1 regulatory network plays critical roles in HIBD. Exp Brain Res 2024; 242:443-449. [PMID: 38147087 PMCID: PMC10806112 DOI: 10.1007/s00221-023-06755-x] [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: 07/14/2023] [Accepted: 11/11/2023] [Indexed: 12/27/2023]
Abstract
The purpose of this study was to identify the target genes of tcon_00044595, elucidate its activation site, and provide novel insights into the pathogenesis and treatment of neonatal hypoxic-ischemic brain damage (HIBD). Through homologous blast analysis, we identified predicted target sequences in the neighboring regions of the long non-coding RNA (lncRNA) tcon_00044595, suggesting that limd1 is its target gene. Starbase was utilized to identify potential candidate microRNAs associated with the lncRNA. The interaction between the candidate microRNAs and limd1 was investigated and validated using various experimental methods including in vitro cell culture, cell transfection, dual fluorescence reporter detection system, and real-time PCR. Homology alignment analysis revealed that the lncRNA tcon_00044595 exhibited a 246 bp homologous sequence at the 3' end of the adjacent limd1 gene, with a conservation rate of 68%. Analysis conducted on Starbase online identified three potential microRNA candidates: miR-3471, miR-883a-5p, and miR-214-3p. Intracellular expression of the limd1 gene was significantly down-regulated upon transfection with miR-3471, while the other two microRNAs did not produce noticeable effects. Luciferase reporter assays identified two interaction sites (UTR-1, UTR-2) between miR-3471 and the limd1 3'UTR, with UTR-1 exhibiting a strong influence. Further CCK8 assay indicated a protective role of miR-3471 during low oxygen stroke in HIBD. The potential regulatory relationship between lncRNA (tcon_00044595), miR-3471, and the target gene limd1 suggests their involvement in the occurrence and development of HIBD, providing new insights for investigating the underlying mechanisms and exploring targeted therapeutic approaches for HIBD.
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Affiliation(s)
- Li Sun
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury;, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Jun Wan
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury;, Children's Hospital of Soochow University, Suzhou, 215025, China
- Department of Pediatrics, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Bin Sun
- Department of Neonatology, Children's Hospital of Soochow University, No.92 Zhongnanjie Road, Suzhou, 215025, Jiangsu, China
| | - Qiuyan Tian
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury;, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Mei Li
- Pediatrics Research Institute, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Li-Xiao Xu
- Pediatrics Research Institute, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Chen-Xi Feng
- Pediatrics Research Institute, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Xiao Tong
- Department of Pediatrics, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Xing Feng
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury;, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Xiaofeng Yang
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury;, Children's Hospital of Soochow University, Suzhou, 215025, China.
- Department of Neonatology, Children's Hospital of Soochow University, No.92 Zhongnanjie Road, Suzhou, 215025, Jiangsu, China.
| | - Xin Ding
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury;, Children's Hospital of Soochow University, Suzhou, 215025, China.
- Department of Neonatology, Children's Hospital of Soochow University, No.92 Zhongnanjie Road, Suzhou, 215025, Jiangsu, China.
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Chen Y, Li X, Xiong Q, Du Y, Luo M, Yi L, Pang Y, Shi X, Wang YT, Dong Z. Inhibiting NLRP3 inflammasome signaling pathway promotes neurological recovery following hypoxic-ischemic brain damage by increasing p97-mediated surface GluA1-containing AMPA receptors. J Transl Med 2023; 21:567. [PMID: 37620837 PMCID: PMC10463885 DOI: 10.1186/s12967-023-04452-5] [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: 03/22/2023] [Accepted: 08/19/2023] [Indexed: 08/26/2023] Open
Abstract
BACKGROUND The nucleotide-binding oligomeric domain (NOD)-like receptor protein 3 (NLRP3) inflammasome is believed to be a key mediator of neuroinflammation and subsequent secondary brain injury induced by ischemic stroke. However, the role and underlying mechanism of the NLRP3 inflammasome in neonates with hypoxic-ischemic encephalopathy (HIE) are still unclear. METHODS The protein expressions of the NLRP3 inflammasome including NLRP3, cysteinyl aspartate specific proteinase-1 (caspase-1) and interleukin-1β (IL-1β), the α-amino-3-hydroxy-5-methyl-4-isoxazole-propionicacid receptor (AMPAR) subunit, and the ATPase valosin-containing protein (VCP/p97), were determined by Western blotting. The interaction between p97 and AMPA glutamate receptor 1 (GluA1) was determined by co-immunoprecipitation. The histopathological level of hypoxic-ischemic brain damage (HIBD) was determined by triphenyltetrazolium chloride (TTC) staining. Polymerase chain reaction (PCR) and Western blotting were used to confirm the genotype of the knockout mice. Motor functions, including myodynamia and coordination, were evaluated by using grasping and rotarod tests. Hippocampus-dependent spatial cognitive function was measured by using the Morris-water maze (MWM). RESULTS We reported that the NLRP3 inflammasome signaling pathway, such as NLRP3, caspase-1 and IL-1β, was activated in rats with HIBD and oxygen-glucose deprivation (OGD)-treated cultured primary neurons. Further studies showed that the protein level of the AMPAR GluA1 subunit on the hippocampal postsynaptic membrane was significantly decreased in rats with HIBD, and it could be restored to control levels after treatment with the specific caspase-1 inhibitor AC-YVAD-CMK. Similarly, in vitro studies showed that OGD reduced GluA1 protein levels on the plasma membrane in cultured primary neurons, whereas AC-YVAD-CMK treatment restored this reduction. Importantly, we showed that OGD treatment obviously enhanced the interaction between p97 and GluA1, while AC-YVAD-CMK treatment promoted the dissociation of p97 from the GluA1 complex and consequently facilitated the localization of GluA1 on the plasma membrane of cultured primary neurons. Finally, we reported that the deficits in motor function, learning and memory in animals with HIBD, were ameliorated by pharmacological intervention or genetic ablation of caspase-1. CONCLUSION Inhibiting the NLRP3 inflammasome signaling pathway promotes neurological recovery in animals with HIBD by increasing p97-mediated surface GluA1 expression, thereby providing new insight into HIE therapy.
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Affiliation(s)
- Yuxin Chen
- Growth, Development, and Mental Health of Children and Adolescence Center, Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Xiaohuan Li
- Growth, Development, and Mental Health of Children and Adolescence Center, Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Qian Xiong
- Growth, Development, and Mental Health of Children and Adolescence Center, Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Yehong Du
- Growth, Development, and Mental Health of Children and Adolescence Center, Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Man Luo
- Growth, Development, and Mental Health of Children and Adolescence Center, Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Lilin Yi
- Growth, Development, and Mental Health of Children and Adolescence Center, Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Yayan Pang
- Growth, Development, and Mental Health of Children and Adolescence Center, Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Xiuyu Shi
- Growth, Development, and Mental Health of Children and Adolescence Center, Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Yu Tian Wang
- Department of Medicine, Brain Research Centre, Vancouver Coastal Health Research Institute, University of British Columbia, Vancouver, BC, V6T 2B5, Canada
| | - Zhifang Dong
- Growth, Development, and Mental Health of Children and Adolescence Center, Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China.
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St. Pierre M, Duck SA, Nazareth M, Fung C, Jantzie LL, Chavez-Valdez R. Unbiased Quantitative Single-Cell Morphometric Analysis to Identify Microglia Reactivity in Developmental Brain Injury. Life (Basel) 2023; 13:life13040899. [PMID: 37109428 PMCID: PMC10147015 DOI: 10.3390/life13040899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 03/03/2023] [Accepted: 03/10/2023] [Indexed: 03/31/2023] Open
Abstract
Microglia morphological studies have been limited to the process of reviewing the most common characteristics of a group of cells to conclude the likelihood of a “pathological” milieu. We have developed an Imaris-software-based analytical pipeline to address selection and operator biases, enabling use of highly reproducible machine-learning algorithms to quantify at single-cell resolution differences between groups. We hypothesized that this analytical pipeline improved our ability to detect subtle yet important differences between groups. Thus, we studied the temporal changes in Iba1+ microglia-like cell (MCL) populations in the CA1 between P10–P11 and P18–P19 in response to intrauterine growth restriction (IUGR) at E12.5 in mice, chorioamnionitis (chorio) at E18 in rats and neonatal hypoxia–ischemia (HI) at P10 in mice. Sholl and convex hull analyses differentiate stages of maturation of Iba1+ MLCs. At P10–P11, IUGR or HI MLCs were more prominently ‘ameboid’, while chorio MLCs were hyper-ramified compared to sham. At P18–P19, HI MLCs remained persistently ‘ameboid’ to ‘transitional’. Thus, we conclude that this unbiased analytical pipeline, which can be adjusted to other brain cells (i.e., astrocytes), improves sensitivity to detect previously elusive morphological changes known to promote specific inflammatory milieu and lead to worse outcomes and therapeutic responses.
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Affiliation(s)
- Mark St. Pierre
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA
| | - Sarah Ann Duck
- Department of Molecular and Cellular Biology, Johns Hopkins University Krieger School of Arts and Sciences, Baltimore, MD 21205, USA
| | - Michelle Nazareth
- Department of Molecular and Cellular Biology, Johns Hopkins University Krieger School of Arts and Sciences, Baltimore, MD 21205, USA
| | - Camille Fung
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, UT 84132, USA
| | - Lauren L. Jantzie
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA
| | - Raul Chavez-Valdez
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA
- Correspondence: ; Tel.: +(410)-955-7156
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Wang S, Gao Z, Yang Y, Zhang Q, Huang J, Wang B, Lei S, Tan Q, Liu D, Guo L, Song Y, Liu J, Ma T, Tian Y. Sonodynamic Therapy With Concentric Ultrasound Imaging Array for Precision Theranostics for Atherosclerotic Plaque. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2022; 69:3270-3283. [PMID: 36269912 DOI: 10.1109/tuffc.2022.3215436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Atherosclerotic cardiovascular disease is a major cause of human disability and mortality. Our previous study demonstrated the safety and efficacy of sonodynamic therapy (SDT) on atherosclerotic plaques. However, traditional single-element therapeutic transducer has single acoustic field, and positioning therapeutic and imaging transducers in the same position is difficult during ultrasound imaging-guided SDT. Continuously changing the position of transducers to intervene lesions in different positions is required, increasing the difficulty of treatment. Thus, an SDT device with precise theranostics is required. Therefore, we designed and fabricated a "concentric ultrasound transducer for theranostics" (CUST-T), comprising a central 8-MHz linear array transducer for ultrasound imaging, and a peripheral 1-MHz hollow two-dimensional (2-D) planar array transducer for generating phased-array focused ultrasound (PAFUS). The CUST-T exhibited high imaging resolution at a distance of up to 20 mm from the transducer and could generate a personalized complex PAFUS acoustic field to match various lesions. In vitro biomedical results showed that PAFUS-SDT induced RAW264.7-derived foam cell apoptosis leading to a targeting field apoptotic rate 4.36-6.24 times that of the nontargeting field and the significant apoptotic region was consistent with the PAFUS acoustic field. In vivo, PAFUS-SDT guided by ultrasound imaging significantly increased the lumen area ( ) and collagen level ( ), whereas the wall thickness ( ) and lipid content ( ) of rabbit femoral artery were reduced. In conclusion, CUST-T provided image guidance sufficient for accurate SDT for atherosclerotic plaques in peripheral arteries and could be applied in clinical practice.
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Bourget C, Adams KV, Morshead CM. Reduced microglia activation following metformin administration or microglia ablation is sufficient to prevent functional deficits in a mouse model of neonatal stroke. J Neuroinflammation 2022; 19:146. [PMID: 35705953 PMCID: PMC9199194 DOI: 10.1186/s12974-022-02487-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 04/29/2022] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Neonatal stroke is a devastating insult that can lead to life-long impairments. In response to hypoxic-ischaemic injury, there is loss of neurons and glia as well as a neuroinflammatory response mediated by resident immune cells, including microglia and astrocytes, which can exacerbate damage. Administration of the antidiabetic drug metformin has been shown to improve functional outcomes in preclinical models of brain injury and the cellular basis for metformin-mediated recovery is unknown. Given metformin's demonstrated anti-inflammatory properties, we investigated its role in regulating the microglia activation and used a microglia ablation strategy to investigate the microglia-mediated outcomes in a mouse model of neonatal stroke. METHODS Hypoxia-ischaemia (H-I) was performed on post-natal day 8. Metformin was administered for one week, starting one day after injury. Immunohistochemistry was used to examine the spatiotemporal response of microglia and astrocytes after hypoxia-ischaemia, with or without metformin treatment. To evaluate the effects of microglia depletion after hypoxia-ischaemia, we delivered Plexxikon 5622 for 1 or 2 weeks post-injury. The regional pattern of microglia and astrocyte depletion was assessed through immunohistochemistry. Motor behaviour was assessed with the righting reflex, hindlimb suspension, grip strength and cylinder tests. RESULTS Herein, we revealed a spatiotemporally regulated response of microglia and astrocytes after hypoxia-ischaemia. Metformin treatment after hypoxia-ischaemia had no effect on microglia number and proliferation, but significantly reduced microglia activation in all regions examined, concomitant with improved behavioural outcomes in injured mice. Plexxikon 5622 treatment successfully ablated microglia, resulting in a > 90% depletion in microglia in the neonatal brain. Microglia rapidly repopulated upon treatment cessation of Plexxikon. Most interesting, microglia ablation was sufficient to reduce functional deficits after hypoxia-ischaemia, mimicking the effects of 1 week of metformin treatment post-injury. CONCLUSION These results highlight the importance of regulating the neuroinflammatory response after neonatal stroke to promote recovery.
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Affiliation(s)
- Clara Bourget
- Institute of Medical Sciences, University of Toronto, Toronto, M5S1A8, Canada
| | - Kelsey V Adams
- Institute of Medical Sciences, University of Toronto, Toronto, M5S1A8, Canada
| | - Cindi M Morshead
- Institute of Medical Sciences, University of Toronto, Toronto, M5S1A8, Canada.
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Room 1006, Toronto, ON, M5S3E1, Canada.
- Division of Anatomy, Department of Surgery, University of Toronto, Toronto, M5S1A8, Canada.
- Institute of Biomedical Engineering, University of Toronto, Toronto, M5S3E1, Canada.
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Guo L, Zhu L. Multiple Roles of Peripheral Immune System in Modulating Ischemia/Hypoxia-Induced Neuroinflammation. Front Mol Biosci 2021; 8:752465. [PMID: 34881289 PMCID: PMC8645603 DOI: 10.3389/fmolb.2021.752465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 10/05/2021] [Indexed: 12/20/2022] Open
Abstract
Given combined efforts of neuroscience and immunology, increasing evidence has revealed the critical roles of the immune system in regulating homeostasis and disorders of the central nervous system (CNS). Microglia have long been considered as the only immune cell type in parenchyma, while at the interface between CNS and the peripheral (meninges, choroid plexus, and perivascular space), embryonically originated border-associated macrophages (BAMs) and multiple surveilling leukocytes capable of migrating into and out of the brain have been identified to function in the healthy brain. Hypoxia-induced neuroinflammation is the key pathological procedure that can be detected in healthy people at high altitude or in various neurodegenerative diseases, during which a very thin line between a beneficial response of the peripheral immune system in maintaining brain homeostasis and a pathological role in exacerbating neuroinflammation has been revealed. Here, we are going to focus on the role of the peripheral immune system and its crosstalk with CNS in the healthy brain and especially in hypobaric or ischemic hypoxia-associated neuroinflammation.
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Affiliation(s)
- Liang Guo
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Lingling Zhu
- Beijing Institute of Basic Medical Sciences, Beijing, China.,University of Nanhua, Hengyang, China.,Anhui Medical University, Hefei, China
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Yuan J, Li L, Yang Q, Ran H, Wang J, Hu K, Pu W, Huang J, Wen L, Zhou L, Jiang Y, Xiong X, Zhang J, Zhou Z. Targeted Treatment of Ischemic Stroke by Bioactive Nanoparticle-Derived Reactive Oxygen Species Responsive and Inflammation-Resolving Nanotherapies. ACS NANO 2021; 15:16076-16094. [PMID: 34606239 DOI: 10.1021/acsnano.1c04753] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Stroke is a primary cause of death and disability worldwide, while effective and safe drugs remain to be developed for its clinical treatment. Herein, we report bioactive nanoparticle-derived multifunctional nanotherapies for ischemic stroke, which are engineered from a pharmacologically active oligosaccharide material (termed as TPCD) prepared by covalently conjugating a radical-scavenging compound (Tempol) and a hydrogen-peroxide-eliminating moiety of phenylboronic acid pinacol ester (PBAP) on β-cyclodextrin. Of note, combined functional moieties of Tempol and PBAP on β-cyclodextrin contribute to antioxidative and anti-inflammatory activities of TPCD. Cellularly, TPCD nanoparticles (i.e., TPCD NPs) reduced oxygen-glucose deprivation-induced overproduction of oxidative mediators, increased antioxidant enzyme expression, and suppressed microglial-mediated inflammation, thereby inhibiting neuronal apoptosis. After intravenous (i.v.) delivery, TPCD NPs could efficiently accumulate at the cerebral ischemic injury site of mice with middle cerebral artery occlusion (MCAO), showing considerable distribution in cells relevant to the pathogenesis of stroke. Therapeutically, TPCD NPs significantly decreased infarct volume and accelerated recovery of neurological function in MCAO mice. Mechanistically, efficacy of TPCD NPs is achieved by its antioxidative, anti-inflammatory, and antiapoptotic effects. Furthermore, TPCD NPs can function as a reactive oxygen species labile nanovehicle to efficiently load and triggerably release an inflammation-resolving peptide Ac2-26, giving rise to an inflammation-resolving nanotherapy (i.e., ATPCD NP). Compared to TPCD NP, ATPCD NP demonstrated notably enhanced in vivo efficacies, largely resulting from its additional inflammation-resolving activity. Consequently, TPCD NP-derived nanomedicines can be further developed as promising targeted therapies for stroke and other inflammation-associated cerebrovascular diseases.
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Affiliation(s)
- Jichao Yuan
- Department of Neurology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Lanlan Li
- Department of Pharmaceutics, College of Pharmacy, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Qinghua Yang
- Department of Pharmaceutics, College of Pharmacy, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Hong Ran
- Department of Neurology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Jie Wang
- Department of Neurology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Kaiyao Hu
- Department of Pharmaceutics, College of Pharmacy, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Wendan Pu
- Department of Pharmaceutics, College of Pharmacy, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Jialu Huang
- Department of Neurology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Lan Wen
- Department of Neurology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Linke Zhou
- Department of Neurology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Ying Jiang
- Department of Neurology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Xiaoxing Xiong
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, China
| | - Jianxiang Zhang
- Department of Pharmaceutics, College of Pharmacy, Third Military Medical University (Army Medical University), Chongqing 400038, China
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Zhenhua Zhou
- Department of Neurology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
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