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Chen J, Zhao X, Huang C, Lin J. Novel insights into molecular signatures and pathogenic cell populations shared by systemic lupus erythematosus and vascular dementia. Funct Integr Genomics 2023; 23:337. [PMID: 37971684 DOI: 10.1007/s10142-023-01270-2] [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: 07/27/2023] [Revised: 11/06/2023] [Accepted: 11/07/2023] [Indexed: 11/19/2023]
Abstract
Although vascular dementia (VD) and systemic lupus erythematosus (SLE) may share immune-mediated pathophysiologic processes, the underlying mechanisms are unclear. This study investigated shared gene signatures in SLE versus VD, as well as their potential molecular mechanisms. Bulk RNA sequencing (RNAseq) and single-cell or single-nucleus RNAseq (sc/snRNAseq) datasets from SLE blood samples and VD brain samples were obtained from Gene Expression Omnibus. The identification of genes associated with both SLE and VD was performed using the weighted gene co-expression network analysis (WGCNA) and machine learning algorithms. For the sc/snRNAseq data, an unbiased clustering pipeline based on Seurat and CellChat was used to determine the cellular landscape profile and examine intracellular communication, respectively. The results were subsequently validated using a mice model of SLE with cognitive dysfunction (female MRL/lpr mice). WGCNA and machine learning identified C1QA, LY96, CD163, and MS4A4A as key genes for SLE and VD. sc/snRNAseq analyses revealed that CD163 and MS4A4A were upregulated in mononuclear phagocytes (MPs) from SLE and VD samples and were associated with monocyte-macrophage differentiation. Intriguingly, LGALS9-associated molecular pathway, as the only signaling pathway common between SLE and VD via CellChat analysis, exhibited significant upregulation in cortical microglia of MRL/lpr mice. Our analyses identified C1QA, LY96, CD163, and MS4A4A as potential biomarkers for SLE and VD. Moreover, the upregulation of CD163/MS4A4A and activation of LGALS9 signaling in MPs may contribute to the pathogenesis of VD with SLE. These findings offer novel insight into the mechanisms underlying VD in SLE patients.
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Affiliation(s)
- Jing Chen
- Department of Neurology, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510630, China
- Department of Rheumatology, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Xiao'feng Zhao
- Department of Rheumatology, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Cheng Huang
- Department of Neurology, Clinical Neuroscience Institute, The First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Jia'xing Lin
- Department of Neurology, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510630, China.
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Tylek K, Trojan E, Leśkiewicz M, Francavilla F, Lacivita E, Leopoldo M, Basta-Kaim A. Stimulation of Formyl Peptide Receptor-2 by the New Agonist CMC23 Protects against Endotoxin-Induced Neuroinflammatory Response: A Study in Organotypic Hippocampal Cultures. ACS Chem Neurosci 2023; 14:3869-3882. [PMID: 37775304 DOI: 10.1021/acschemneuro.3c00525] [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] [Indexed: 10/01/2023] Open
Abstract
A substantial body of evidence demonstrates an association between a malfunction in the resolution of acute inflammation and the development of chronic inflammation. Recently, in this context, the importance of formyl peptide receptor 2 (FPR2) has been underlined. FPR2 activity is modulated by a wide range of endogenous ligands, including specialized pro-resolving mediators (SPMs) (e.g., LXA4 and AT-LXA4) and synthetic ligands. Since SPMs have unfavorable pharmacokinetic properties, we aimed to evaluate the protective and pro-resolving effects of a new potent FPR2 agonist, compound CMC23, in organotypic hippocampal cultures (OHCs) stimulated with lipopolysaccharide (LPS). The protective activity of CMC23 limited the lactate dehydrogenase release in LPS-stimulated cultures. This activity was mediated by the interaction with FPR2 as pretreatment with the FPR2 selective antagonist WRW4 abolished CMC23-induced protection. Furthermore, decreased levels of pro-inflammatory IL-1β and IL-6 were observed after CMC23 administration in LPS-treated OHCs. CMC23 also diminished the LPS-induced increase in IL-17A and both IL-23 subunits p19 and p40 in OHCs. Finally, we demonstrated that CMC23 exerts its beneficial impact via the STAT3/SOCS3 signaling pathway since it attenuated the level of phospho-STAT3 and maintained the LPS-induced SOCS3 levels in OHCs. Collectively, our research implies that the new FPR2 agonist CMC23 has beneficial protective and anti-inflammatory properties in nanomolar doses and FPR2 represents a promising target for the enhancement of inflammation resolution.
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Affiliation(s)
- Kinga Tylek
- Laboratory of Immunoendocrinology, Department of Experimental Neuroendocrinology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna St, Kraków 31-343, Poland
| | - Ewa Trojan
- Laboratory of Immunoendocrinology, Department of Experimental Neuroendocrinology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna St, Kraków 31-343, Poland
| | - Monika Leśkiewicz
- Laboratory of Immunoendocrinology, Department of Experimental Neuroendocrinology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna St, Kraków 31-343, Poland
| | - Fabio Francavilla
- Department of Pharmacy─Drug Sciences, University of Bari, Via Orabona 4, Bari 70125, Italy
| | - Enza Lacivita
- Department of Pharmacy─Drug Sciences, University of Bari, Via Orabona 4, Bari 70125, Italy
| | - Marcello Leopoldo
- Department of Pharmacy─Drug Sciences, University of Bari, Via Orabona 4, Bari 70125, Italy
| | - Agnieszka Basta-Kaim
- Laboratory of Immunoendocrinology, Department of Experimental Neuroendocrinology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna St, Kraków 31-343, Poland
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Chu E, Mychasiuk R, Tsantikos E, Raftery AL, L’Estrange-Stranieri E, Dill LK, Semple BD, Hibbs ML. Regulation of Microglial Signaling by Lyn and SHIP-1 in the Steady-State Adult Mouse Brain. Cells 2023; 12:2378. [PMID: 37830592 PMCID: PMC10571795 DOI: 10.3390/cells12192378] [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: 09/06/2023] [Revised: 09/21/2023] [Accepted: 09/26/2023] [Indexed: 10/14/2023] Open
Abstract
Chronic neuroinflammation and glial activation are associated with the development of many neurodegenerative diseases and neuropsychological disorders. Recent evidence suggests that the protein tyrosine kinase Lyn and the lipid phosphatase SH2 domain-containing inositol 5' phosphatase-1 (SHIP-1) regulate neuroimmunological responses, but their homeostatic roles remain unclear. The current study investigated the roles of Lyn and SHIP-1 in microglial responses in the steady-state adult mouse brain. Young adult Lyn-/- and SHIP-1-/- mice underwent a series of neurobehavior tests and postmortem brain analyses. The microglial phenotype and activation state were examined by immunofluorescence and flow cytometry, and neuroimmune responses were assessed using gene expression analysis. Lyn-/- mice had an unaltered behavioral phenotype, neuroimmune response, and microglial phenotype, while SHIP-1-/- mice demonstrated reduced explorative activity and exhibited microglia with elevated activation markers but reduced granularity. In addition, expression of several neuroinflammatory genes was increased in SHIP-1-/- mice. In response to LPS stimulation ex vivo, the microglia from both Lyn-/- and SHIP-1-/- showed evidence of hyper-activity with augmented TNF-α production. Together, these findings demonstrate that both Lyn and SHIP-1 have the propensity to control microglial responses, but only SHIP-1 regulates neuroinflammation and microglial activation in the steady-state adult brain, while Lyn activity appears dispensable for maintaining brain homeostasis.
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Affiliation(s)
- Erskine Chu
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
- Department of Immunology, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia; (E.T.); (A.L.R.); (E.L.-S.)
| | - Richelle Mychasiuk
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
- Department of Neurology, Alfred Health, Melbourne, VIC 3004, Australia
| | - Evelyn Tsantikos
- Department of Immunology, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia; (E.T.); (A.L.R.); (E.L.-S.)
| | - April L. Raftery
- Department of Immunology, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia; (E.T.); (A.L.R.); (E.L.-S.)
| | - Elan L’Estrange-Stranieri
- Department of Immunology, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia; (E.T.); (A.L.R.); (E.L.-S.)
| | - Larissa K. Dill
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Bridgette D. Semple
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
- Department of Neurology, Alfred Health, Melbourne, VIC 3004, Australia
- Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Margaret L. Hibbs
- Department of Immunology, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia; (E.T.); (A.L.R.); (E.L.-S.)
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McMillan RE, Wang E, Carlin AF, Coufal NG. Human microglial models to study host-virus interactions. Exp Neurol 2023; 363:114375. [PMID: 36907350 PMCID: PMC10521930 DOI: 10.1016/j.expneurol.2023.114375] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 02/13/2023] [Accepted: 03/02/2023] [Indexed: 03/14/2023]
Abstract
Microglia, the resident macrophage of the central nervous system, are increasingly recognized as contributing to diverse aspects of human development, health, and disease. In recent years, numerous studies in both mouse and human models have identified microglia as a "double edged sword" in the progression of neurotropic viral infections: protecting against viral replication and cell death in some contexts, while acting as viral reservoirs and promoting excess cellular stress and cytotoxicity in others. It is imperative to understand the diversity of human microglial responses in order to therapeutically modulate them; however, modeling human microglia has been historically challenging due to significant interspecies differences in innate immunity and rapid transformation upon in vitro culture. In this review, we discuss the contribution of microglia to the neuropathogenesis of key neurotropic viral infections: human immunodeficiency virus 1 (HIV-1), Zika virus (ZIKV), Japanese encephalitis virus (JEV), West Nile virus (WNV), Herpes simplex virus (HSV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We pay special attention to recent work with human stem cell-derived microglia and propose strategies to leverage these powerful models to further uncover species- and disease-specific microglial responses and novel therapeutic interventions for neurotropic viral infections.
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Affiliation(s)
- Rachel E McMillan
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, United States of America; Department of Pathology and Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093, United States of America
| | - Ellen Wang
- Department of Pediatrics, University of California, San Diego, School of Medicine, La Jolla, CA 92093, United States of America; Sanford Consortium for Regenerative Medicine, La Jolla, CA 92093, United States of America
| | - Aaron F Carlin
- Department of Pathology and Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093, United States of America.
| | - Nicole G Coufal
- Department of Pediatrics, University of California, San Diego, School of Medicine, La Jolla, CA 92093, United States of America; Sanford Consortium for Regenerative Medicine, La Jolla, CA 92093, United States of America.
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Morphine and HIV-1 Tat interact to cause region-specific hyperphosphorylation of tau in transgenic mice. Neurosci Lett 2020; 741:135502. [PMID: 33202259 DOI: 10.1016/j.neulet.2020.135502] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 11/08/2020] [Accepted: 11/10/2020] [Indexed: 12/24/2022]
Abstract
Opiate abuse is prevalent among HIV-infected individuals and may exacerbate HIV-associated age-related neurocognitive disorders. However, the extent to which HIV and opiates converge to accelerate pathological traits indicative of brain aging remains unknown. The pathological phospho-isotypes of tau (pSer396, pSer404, pThr205, pSer202, and pThr181) and the tau kinases GSK3β and CDK5/p35 were explored in the striatum, hippocampus, and prefrontal cortex of inducible male and female HIV-1 Tat-transgenic mice, with some receiving escalating doses of morphine for 2 weeks. In the striatum of male mice, pSer396 was increased by co-exposure to morphine and Tat as compared to all other groups. Striatal pSer404 and pThr205 were increased by Tat alone, while pSer202 and pThr181 were unchanged. A comparison between Tat-transgenic female and male mice revealed disparate outcomes for pThr205. No other sex-related changes to tau phosphorylation were observed. In the hippocampus, Tat increased pSer396, while other phosphorylation sites were unchanged and pSer202 was not detected. In the prefrontal cortex, morphine increased pSer396 levels, which were unaffected by Tat, while other phosphorylation sites were unaffected. Assessment of tau kinases revealed no changes to striatal GSK3β (phosphorylated or total) or the total CDK5 levels. Striatal levels of phosphorylated CDK5 and p35, the activator of CDK5, were increased by Tat and with morphine co-exposure, respectively. P35 levels positively correlated with those of pSer396 with Tat and morphine co-exposure. The results reveal region-specific hyperphosphorylation of tau induced by exposure to morphine, Tat, and unique morphine and Tat interactions.
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Aw E, Zhang Y, Carroll M. Microglial responses to peripheral type 1 interferon. J Neuroinflammation 2020; 17:340. [PMID: 33183319 PMCID: PMC7659169 DOI: 10.1186/s12974-020-02003-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 10/19/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Interferon α (IFNα) is a cytokine whose production is increased endogenously in response to viral infection and in autoimmune diseases such as systemic lupus erythematosus (SLE). An elevated IFNα signature has been associated with clinically observed neuro-behavioural deficits such as mild cognitive impairment, fatigue, depression and psychosis in these diseases. However, the mechanisms underlying these neuropsychiatric symptoms remain largely unknown, and it is as yet unclear how IFNα signalling might influence central nervous system (CNS) function. Aberrant microglia-mediated synaptic pruning and function has recently been implicated in several neurodegenerative and neuropsychiatric diseases, but whether and how IFNα modulates these functions are not well defined. METHODS Using a model of peripheral IFNα administration, we investigated gene expression changes due to IFNAR signalling in microglia. Bulk RNA sequencing on sorted microglia from wild type and microglia-specific Ifnar1 conditional knockout mice was performed to evaluate IFNα and IFNAR signalling-dependent changes in gene expression. Furthermore, the effects of IFNα on microglia morphology and synapse engulfment were assessed, via immunohistochemistry and flow cytometry. RESULTS We found that IFNα exposure through the periphery induces a unique gene signature in microglia that includes the expected upregulation of multiple interferon-stimulated genes (ISGs), as well as the complement component C4b. We additionally characterized several IFNα-dependent changes in microglial phenotype, including expression of CD45 and CD68, cellular morphology and presynaptic engulfment, that reveal subtle brain region-specific differences. Finally, by specifically knocking down expression of IFNAR1 on microglia, we show that these changes are largely attributable to direct IFNAR signalling on microglia and not from indirect signalling effects through other CNS parenchymal cell types which are capable of IFNα-IFNAR signal transduction. CONCLUSIONS Peripheral IFNα induces unique genetic and phenotypic changes in microglia that are largely dependent on direct signalling through microglial IFNAR. The IFNα-induced upregulation of C4b could play important roles in the context of aberrant synaptic pruning in neuropsychiatric disease.
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Affiliation(s)
- Ernest Aw
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Division of Medical Sciences, Harvard Medical School, Boston, MA, USA
| | - Yingying Zhang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
| | - Michael Carroll
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA.
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Vigil FA, Bozdemir E, Bugay V, Chun SH, Hobbs M, Sanchez I, Hastings SD, Veraza RJ, Holstein DM, Sprague SM, M Carver C, Cavazos JE, Brenner R, Lechleiter JD, Shapiro MS. Prevention of brain damage after traumatic brain injury by pharmacological enhancement of KCNQ (Kv7, "M-type") K + currents in neurons. J Cereb Blood Flow Metab 2020; 40:1256-1273. [PMID: 31272312 PMCID: PMC7238379 DOI: 10.1177/0271678x19857818] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Nearly three million people in the USA suffer traumatic brain injury (TBI) yearly; however, there are no pre- or post-TBI treatment options available. KCNQ2-5 voltage-gated K+ channels underlie the neuronal "M current", which plays a dominant role in the regulation of neuronal excitability. Our strategy towards prevention of TBI-induced brain damage is predicated on the suggested hyper-excitability of neurons induced by TBIs, and the decrease in neuronal excitation upon pharmacological augmentation of M/KCNQ K+ currents. Seizures are very common after a TBI, making further seizures and development of epilepsy disease more likely. Our hypothesis is that TBI-induced hyperexcitability and ischemia/hypoxia lead to metabolic stress, cell death and a maladaptive inflammatory response that causes further downstream morbidity. Using the mouse controlled closed-cortical impact blunt TBI model, we found that systemic administration of the prototype M-channel "opener", retigabine (RTG), 30 min after TBI, reduces the post-TBI cascade of events, including spontaneous seizures, enhanced susceptibility to chemo-convulsants, metabolic stress, inflammatory responses, blood-brain barrier breakdown, and cell death. This work suggests that acutely reducing neuronal excitability and energy demand via M-current enhancement may be a novel model of therapeutic intervention against post-TBI brain damage and dysfunction.
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Affiliation(s)
- Fabio A Vigil
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Eda Bozdemir
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Vladislav Bugay
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Sang H Chun
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - MaryAnn Hobbs
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Isamar Sanchez
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Shayne D Hastings
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Rafael J Veraza
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Deborah M Holstein
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Shane M Sprague
- Department of Neurosurgery, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Chase M Carver
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Jose E Cavazos
- Department of Neurology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Robert Brenner
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
| | - James D Lechleiter
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Mark S Shapiro
- Department of Cellular and Integrative Physiology, University of Texas Health San Antonio, San Antonio, TX, USA
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Morris DR, Bounds SE, Liu H, Ding WQ, Chen Y, Liu Y, Cai J. Exosomal MiRNA Transfer between Retinal Microglia and RPE. Int J Mol Sci 2020; 21:ijms21103541. [PMID: 32429541 PMCID: PMC7279010 DOI: 10.3390/ijms21103541] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/10/2020] [Accepted: 05/14/2020] [Indexed: 12/16/2022] Open
Abstract
The retinal pigment epithelium (RPE), the outermost layer of the retina, provides essential support to both the neural retina and choroid. Additionally, the RPE is highly active in modulating functions of immune cells such as microglia, which migrate to the subretinal compartment during aging and age-related degeneration. Recently, studies have highlighted the important roles of microRNA (miRNA) in the coordination of general tissue maintenance as well as in chronic inflammatory conditions. In this study, we analyzed the miRNA profiles in extracellular vesicles (EVs) released by the RPE, and identified and validated miRNA species whose expression levels showed age-dependent changes in the EVs. Using co-culture of RPE and retinal microglia, we further demonstrated that miR-21 was transferred between the two types of cells, and the increased miR-21 in microglia influenced the expression of genes downstream of the p53 pathway. These findings suggest that exosome-mediated miRNA transfer is a signaling mechanism that contributes to the regulation of microglia function in the aging retina.
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Affiliation(s)
- Dorothea R. Morris
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (D.R.M.); (Y.C.)
| | - Sarah E. Bounds
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (S.E.B.); (H.L.)
| | - Huanhuan Liu
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (S.E.B.); (H.L.)
| | - Wei-Qun Ding
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA;
| | - Yan Chen
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (D.R.M.); (Y.C.)
- Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Yin Liu
- Department of Neurobiology and Anatomy, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Correspondence: (Y.L.); (J.C.); Tel.: +1-713-500-5632 (Y.L.); +1-405-271-2226 (J.C.)
| | - Jiyang Cai
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (D.R.M.); (Y.C.)
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (S.E.B.); (H.L.)
- Correspondence: (Y.L.); (J.C.); Tel.: +1-713-500-5632 (Y.L.); +1-405-271-2226 (J.C.)
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Gavegnano C, Haile WB, Hurwitz S, Tao S, Jiang Y, Schinazi RF, Tyor WR. Baricitinib reverses HIV-associated neurocognitive disorders in a SCID mouse model and reservoir seeding in vitro. J Neuroinflammation 2019; 16:182. [PMID: 31561750 PMCID: PMC6764124 DOI: 10.1186/s12974-019-1565-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 08/28/2019] [Indexed: 12/12/2022] Open
Abstract
Background Since HIV-associated neurocognitive disorders (HANDs) occur in up to half of HIV-positive individuals, even with combined antiretroviral therapy (cART), adjunctive therapies are needed. Chronic CNS inflammation contributes to HAND and HIV encephalitis (HIVE). Baricitinib is a JAK 1/2 inhibitor approved in the USA, EU, and Japan for rheumatoid arthritis, demonstrating potent inhibition of IL-6, D-dimer, CRP, TNF-α, IFN-α/β, and other pro-inflammatory cytokines. Methods Our modified murine HAND model was used to evaluate the ability of baricitinib to cross the blood-brain barrier (BBB) and modulate monocyte/macrophage-driven HAND. Severity of HAND was measured by assessing cognitive performance of low- and high-dose baricitinib treated versus untreated HAND mice. The severity of brain neuroinflammation was evaluated in these mouse groups after flow cytometric analyses. We also assessed the ability of baricitinib to block events in myeloid and lymphoid cells in vitro that may undergird the persistence of HIV in the central nervous system (CNS) in primary human macrophages (Mϕ) and lymphocytes including HIV replication, HIV-induced activation, reservoir expansion, and reservoir maintenance. Results In vivo, both doses of 10 and 50 mg/kg qd baricitinib crossed the BBB and reversed behavioral abnormalities conferred by HIV infection. Moreover, baricitinib significantly reduced HIV-induced neuroinflammation marked by glial activation: activated microglia (MHCII+/CD45+) and astrogliosis (GFAP). Baricitinib also significantly reduced the percentage of p24+ human macrophages in mouse brains (p < 0.05 versus HAND mice; t test). In vitro, baricitinib significantly reduced markers of persistence, reservoir size, and reseeding in Mϕ. Conclusion These results show that blocking the JAK/STAT pathway reverses cognitive deficits and curtails inflammatory markers in HAND in mice. Our group recently reported safety and tolerability of ruxolitinib in HIV-infected individuals (Marconi et al., Safety, tolerability and immunologic activity of ruxolitinib added to suppressive ART, 2019), underscoring potential safety and utility of JAK inhibitors for additional human trials. The data reported herein coupled with our recent human trial with JAK inhibitors provide compelling preclinical data and impetus for considering a trial of baricitinib in HAND individuals treated with cART to reverse cognitive deficits and key events driving viral persistence. Electronic supplementary material The online version of this article (10.1186/s12974-019-1565-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Christina Gavegnano
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University, Atlanta, GA, 30322, USA.,Emory Center for AIDS Research (CFAR), Emory University, Atlanta, GA, 30322, USA
| | - Woldeab B Haile
- Emory Center for AIDS Research (CFAR), Emory University, Atlanta, GA, 30322, USA.,Department of Neurology, School of Medicine, Emory University, Atlanta, GA, 30209, USA.,Atlanta Veterans Affairs Medical Center, Decatur, GA, 30033, USA
| | - Selwyn Hurwitz
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University, Atlanta, GA, 30322, USA.,Emory Center for AIDS Research (CFAR), Emory University, Atlanta, GA, 30322, USA
| | - Sijia Tao
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University, Atlanta, GA, 30322, USA.,Emory Center for AIDS Research (CFAR), Emory University, Atlanta, GA, 30322, USA
| | - Yong Jiang
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University, Atlanta, GA, 30322, USA.,Emory Center for AIDS Research (CFAR), Emory University, Atlanta, GA, 30322, USA
| | - Raymond F Schinazi
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University, Atlanta, GA, 30322, USA. .,Emory Center for AIDS Research (CFAR), Emory University, Atlanta, GA, 30322, USA.
| | - William R Tyor
- Emory Center for AIDS Research (CFAR), Emory University, Atlanta, GA, 30322, USA. .,Department of Neurology, School of Medicine, Emory University, Atlanta, GA, 30209, USA. .,Atlanta Veterans Affairs Medical Center, Decatur, GA, 30033, USA.
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Bhat SA, Sood A, Shukla R, Hanif K. AT2R Activation Prevents Microglia Pro-inflammatory Activation in a NOX-Dependent Manner: Inhibition of PKC Activation and p47phox Phosphorylation by PP2A. Mol Neurobiol 2018; 56:3005-3023. [DOI: 10.1007/s12035-018-1272-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 07/19/2018] [Indexed: 12/22/2022]
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11
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Malada-Edelstein YF, Hadad N, Levy R. Regulatory role of cytosolic phospholipase A 2 alpha in the induction of CD40 in microglia. J Neuroinflammation 2017; 14:33. [PMID: 28187742 PMCID: PMC5303221 DOI: 10.1186/s12974-017-0811-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 02/02/2017] [Indexed: 01/25/2023] Open
Abstract
Background The aberrant expression of CD40, a co-stimulatory receptor found on the antigen-presenting cells, is involved in the pathogenesis of various degenerative diseases. Our previous study demonstrated that the reduction of cytosolic phospholipase A2 alpha (cPLA2α) protein overexpression and activation in the spinal cord of a mouse model of ALS, hmSOD1 G93A, inhibited CD40 upregulation in microglia. The present study was designed to determine whether cPLA2α has a direct, participatory role in the molecular events leading to CD40 induction. Methods Cultures of primary mouse microglia or BV-2 microglia cell line exposed to lipopolysaccharide (LPS) or interferon gamma (IFNγ) for different periods of time, in order to study the role of cPLA2α in the events leading to CD40 protein induction. Results Addition of LPS or IFNγ caused a significant upregulation of cPLA2α and of CD40, while prevention of cPLA2α upregulation by a specific oligonucleotide antisense (AS) prevented the induction of CD40, suggesting a role of cPLA2α in the induction of CD40. Addition of LPS to microglia caused an immediate activation of cPLA2α detected by its phosphorylated form, while addition of IFNγ induced cPLA2α activation at a later time scale (4 h). The activation of cPLA2α is mediated by ERK activity. Suppression of cPLA2α activity inhibited superoxide production by NOX2-NADPH oxidase and activation of NF-κB detected by the phosphorylation of p65 on serine 536 at 15 min by LPS and at 4 h by IFNγ. Inhibition of NOX2 prevented NF-κB activation and CD40 induction but did not affect cPLA2α activation, suggesting cPLA2α is located upstream to NOX2 and NF-κB. The activation of cPLA2 by LPS was mediated by both adaptor proteins downstream to LPS receptor; TRIF and MyD88, while the activation of cPLA2α by IFNγ was mediated by the secreted TNF-α at 4 h. The early activation of STAT1α (detected by phospho-serine727 and phoshpo-tyrosine701) by IFNγ and the late activation of STAT1α by LPS were not affected in the presence of cPLA2α inhibitors, indicating that STAT1α is not under cPLA2α regulation. Conclusions Our results show for the first time that cPLA2 upregulates CD40 protein expression induced by either LPS or IFNγ, and this regulatory effect is mediated via the activation of NOX2-NADPH oxidase and NF-κB. Cumulatively, our results indicate that cPLA2α may serve as a pivotal amplifier of the inflammatory response in the CNS.
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Affiliation(s)
- Yafa Fetfet Malada-Edelstein
- Infectious Diseases Laboratory, Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, 84105, Beer-Sheva, Israel
| | - Nurit Hadad
- Infectious Diseases Laboratory, Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, 84105, Beer-Sheva, Israel
| | - Rachel Levy
- Infectious Diseases Laboratory, Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, 84105, Beer-Sheva, Israel.
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Kim JY, Park J, Chang JY, Kim SH, Lee JE. Inflammation after Ischemic Stroke: The Role of Leukocytes and Glial Cells. Exp Neurobiol 2016; 25:241-251. [PMID: 27790058 PMCID: PMC5081470 DOI: 10.5607/en.2016.25.5.241] [Citation(s) in RCA: 207] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 10/12/2016] [Accepted: 10/17/2016] [Indexed: 12/17/2022] Open
Abstract
The immune response after stroke is known to play a major role in ischemic brain pathobiology. The inflammatory signals released by immune mediators activated by brain injury sets off a complex series of biochemical and molecular events which have been increasingly recognized as a key contributor to neuronal cell death. The primary immune mediators involved are glial cells and infiltrating leukocytes, including neutrophils, monocytes and lymphocyte. After ischemic stroke, activation of glial cells and subsequent release of pro- and anti-inflammatory signals are important for modulating both neuronal cell damage and wound healing. Infiltrated leukocytes release inflammatory mediators into the site of the lesion, thereby exacerbating brain injury. This review describes how the roles of glial cells and circulating leukocytes are a double-edged sword for neuroinflammation by focusing on their detrimental and protective effects in ischemic stroke. Here, we will focus on underlying characterize of glial cells and leukocytes under inflammation after ischemic stroke.
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Affiliation(s)
- Jong Youl Kim
- Department of Anatomy, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Joohyun Park
- Department of Anatomy, Yonsei University College of Medicine, Seoul 03722, Korea.; Bk21 Plus Project for Medical Sciences and Brain Research Institute, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Ji Young Chang
- Department of Anatomy, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Sa-Hyun Kim
- Department of Clinical Laboratory Science, Semyung University, Jaecheon 27136, Korea
| | - Jong Eun Lee
- Department of Anatomy, Yonsei University College of Medicine, Seoul 03722, Korea.; Bk21 Plus Project for Medical Sciences and Brain Research Institute, Yonsei University College of Medicine, Seoul 03722, Korea
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Cannabinoid CB2 Receptor Mediates Nicotine-Induced Anti-Inflammation in N9 Microglial Cells Exposed to β Amyloid via Protein Kinase C. Mediators Inflamm 2016; 2016:4854378. [PMID: 26884647 PMCID: PMC4738711 DOI: 10.1155/2016/4854378] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2015] [Revised: 12/07/2015] [Accepted: 12/16/2015] [Indexed: 01/08/2023] Open
Abstract
Background. Reducing β amyloid- (Aβ-) induced microglial activation is considered to be effective in treating Alzheimer's disease (AD). Nicotine attenuates Aβ-induced microglial activation; the mechanism, however, is still elusive. Microglia could be activated into classic activated state (M1 state) or alternative activated state (M2 state); the former is cytotoxic and the latter is neurotrophic. In this investigation, we hypothesized that nicotine attenuates Aβ-induced microglial activation by shifting microglial M1 to M2 state, and cannabinoid CB2 receptor and protein kinase C mediate the process. Methods. We used Aβ1–42 to activate N9 microglial cells and observed nicotine-induced effects on microglial M1 and M2 biomarkers by using western blot, immunocytochemistry, and enzyme-linked immunosorbent assay (ELISA). Results. We found that nicotine reduced the levels of M1 state markers, including inducible nitric oxide synthase (iNOS) expression and tumor necrosis factor α (TNF-α) and interleukin- (IL-) 6 releases; meanwhile, it increased the levels of M2 state markers, including arginase-1 (Arg-1) expression and brain-derived neurotrophic factor (BDNF) release, in the Aβ-stimulated microglia. Coadministration of cannabinoid CB2 receptor antagonist or protein kinase C (PKC) inhibitor partially abolished the nicotine-induced effects. Conclusion. These findings indicated that cannabinoid CB2 receptor mediates nicotine-induced anti-inflammation in microglia exposed to Aβ via PKC.
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Assembly, organization and regulation of cell-surface receptors by lectin–glycan complexes. Biochem J 2015; 469:1-16. [DOI: 10.1042/bj20150461] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Galectins are a family of β-galactoside-binding lectins carrying at least one consensus sequence in the carbohydrate-recognition domain. Properties of glycosylated ligands, such as N- and O-glycan branching, LacNAc (N-acetyl-lactosamine) content and the balance of α2,3- and α2,6-linked sialic acid dramatically influence galectin binding to a preferential set of counter-receptors. The presentation of specific glycans in galectin-binding partners is also critical, as proper orientation and clustering of oligosaccharide ligands on multiple carbohydrate side chains increase the binding avidity of galectins for particular glycosylated receptors. When galectins are released from the cells, they typically concentrate on the cell surface and the local matrix, raising their local concentration. Thus galectins can form their own multimers in the extracellular milieu, which in turn cross-link glycoconjugates on the cell surface generating galectin–glycan complexes that modulate intracellular signalling pathways, thus regulating cellular processes such as apoptosis, proliferation, migration and angiogenesis. Subtle changes in receptor expression, rates of protein synthesis, activities of Golgi enzymes, metabolite concentrations supporting glycan biosynthesis, density of glycans, strength of protein–protein interactions at the plasma membrane and stoichiometry may modify galectin–glycan complexes. Although galectins are key contributors to the formation of these extended glycan complexes leading to promotion of receptor segregation/clustering, and inhibition of receptor internalization by surface retention, when these complexes are disrupted, some galectins, particularly galectin-3 and -4, showed the ability to drive clathrin-independent mechanisms of endocytosis. In the present review, we summarize the data available on the assembly, hierarchical organization and regulation of conspicuous galectin–glycan complexes, and their implications in health and disease.
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Sun MK, Nelson TJ, Alkon DL. Towards universal therapeutics for memory disorders. Trends Pharmacol Sci 2015; 36:384-94. [DOI: 10.1016/j.tips.2015.04.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 04/07/2015] [Accepted: 04/08/2015] [Indexed: 12/22/2022]
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16
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Galectin-1-secreting neural stem cells elicit long-term neuroprotection against ischemic brain injury. Sci Rep 2015; 5:9621. [PMID: 25858671 PMCID: PMC4392363 DOI: 10.1038/srep09621] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 03/09/2015] [Indexed: 12/20/2022] Open
Abstract
Galectin-1 (gal-1), a special lectin with high affinity to β-galactosides, is implicated in protection against ischemic brain injury. The present study investigated transplantation of gal-1-secreting neural stem cell (s-NSC) into ischemic brains and identified the mechanisms underlying protection. To accomplish this goal, secretory gal-1 was stably overexpressed in NE-4C neural stem cells. Transient cerebral ischemia was induced in mice by middle cerebral artery occlusion for 60 minutes and s-NSCs were injected into the striatum and cortex within 2 hours post-ischemia. Brain infarct volume and neurological performance were assessed up to 28 days post-ischemia. s-NSC transplantation reduced infarct volume, improved sensorimotor and cognitive functions, and provided more robust neuroprotection than non-engineered NSCs or gal-1-overexpressing (but non-secreting) NSCs. White matter injury was also ameliorated in s-NSC-treated stroke mice. Gal-1 modulated microglial function in vitro, by attenuating secretion of pro-inflammatory cytokines (TNF-α and nitric oxide) in response to LPS stimulation and enhancing production of anti-inflammatory cytokines (IL-10 and TGF-β). Gal-1 also shifted microglia/macrophage polarization toward the beneficial M2 phenotype in vivo by reducing CD16 expression and increasing CD206 expression. In sum, s-NSC transplantation confers robust neuroprotection against cerebral ischemia, probably by alleviating white matter injury and modulating microglial/macrophage function.
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Abdominal obesity contributes to neurocognitive impairment in HIV-infected patients with increased inflammation and immune activation. J Acquir Immune Defic Syndr 2015; 68:281-8. [PMID: 25469522 DOI: 10.1097/qai.0000000000000458] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
OBJECTIVE We tested our hypothesis that abdominal obesity when associated with increased levels of systemic and central nervous system immunoinflammatory mediators contributes to neurocognitive impairment (NCI). DESIGN Cross-sectional. SETTING Six Academic Centers. PARTICIPANTS One hundred fifty-two patients with plasma HIV RNA <1000 copies per milliliter had clinical evaluations and cognitive function quantified by global deficit scores (GDS). OUTCOME MEASURES GDS, waist circumference (WC) and plasma IL-6, sCD163, and sCD14 and CSF sCD40L, sTNFrII, MCP-1, sICAM, and MMP-9. RESULTS WC and plasma IL-6 levels positively correlated with GDS; the WC correlation was strongest in the high tertile of IL-6 (ρ = 0.39, P = 0.005). IL-6 correlated with GDS only if WC was ≥99 cm. In the high tertile of CSF sCD40L, a biomarker of macrophage and microglial activation, the correlation of IL-6 to GDS was strongest (ρ = 0.60, P < 0.0001). Across 3-5 visits within ±1 year of the index visit, GDS remained worse in patients with IL-6 levels in the high versus low tertile (P = 0.02). Path analysis to explore potential mediators of NCI produced a strong integrated model for patients in the high CSF sCD40L tertile. In this model, WC affected GDS both directly and through a second path that was mediated by IL-6. Inclusion of plasma sCD14 levels strengthened the model. NCI was more common in men and for individuals with components of the metabolic syndrome. CONCLUSIONS Neurocognitive function was significantly linked to abdominal obesity, systemic inflammation (high IL-6), and immune activation in plasma (high sCD14) and CSF (high sCD40L). Abdominal obesity, inflammation, and central nervous system immune activation are potential therapeutic targets for NCI in HIV-positive patients.
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Su F, Yi H, Xu L, Zhang Z. Fluoxetine and S-citalopram inhibit M1 activation and promote M2 activation of microglia in vitro. Neuroscience 2015; 294:60-8. [PMID: 25711936 DOI: 10.1016/j.neuroscience.2015.02.028] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 02/12/2015] [Accepted: 02/13/2015] [Indexed: 12/27/2022]
Abstract
Increasing evidence has suggested that microglia dysfunction plays an important role in the pathogenesis of depression. Both classical activation (M1 activation) and alternative activation (M2 activation) may be involved in the process. M1-activated microglia secrete various pro-inflammatory cytokines and neurotoxic mediators, which may contribute to the development of depression, while M2-activated microglia promote tissue reconstruction by releasing anti-inflammatory cytokines involved in the process of depression. Selective serotonin reuptake inhibitors (SSRIs) are first-line treatments for depression, and their effects on immune system modulation have recently gained attention. Several studies have suggested that SSRIs affect the M1 activation of microglia, but results have varied. In addition, little is known about the effect of SSRIs on M2 activation in depression. The aim of this study was to investigate the effects of fluoxetine and S-citalopram, two widely used SSRIs in clinical, on both the M1 and M2 activation of microglia (the murine BV2 cell line and mouse primary microglia cell). The indexes of activation were measured by real-time polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA) and Western blot. The present results showed that both fluoxetine and S-citalopram significantly down-regulated the indexes of M1 activation and up-regulated the M2 activation indexes on mRNA and protein levels either in cell line or primary cells. Taken together, the results suggested that fluoxetine and S-citalopram modulated the immune system by inhibiting M1 activation and by improving M2 activation of microglia and that the immune system modulation may partially mediate the therapeutic effects of antidepressant drugs-SSRIs.
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Affiliation(s)
- F Su
- The Department of Neurology of Affiliated ZhongDa Hospital, The Institute of Neuropsychiatry and Medical School of Southeast University, Nanjing, China
| | - H Yi
- The Department of Neurology of Affiliated ZhongDa Hospital, The Institute of Neuropsychiatry and Medical School of Southeast University, Nanjing, China
| | - L Xu
- Laboratory of Learning and Memory, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Z Zhang
- The Department of Neurology of Affiliated ZhongDa Hospital, The Institute of Neuropsychiatry and Medical School of Southeast University, Nanjing, China.
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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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20
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Brown LAM, Scarola J, Smith AJ, Sanberg PR, Tan J, Giunta B. The role of tau protein in HIV-associated neurocognitive disorders. Mol Neurodegener 2014; 9:40. [PMID: 25304757 PMCID: PMC4210623 DOI: 10.1186/1750-1326-9-40] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 09/15/2014] [Indexed: 11/14/2022] Open
Abstract
Given the increased life expectancy of human immunodeficiency virus (HIV) infected individuals treated with combination antiretroviral therapy (cART) and the ongoing inflammation observed in the brains of these patients, it is likely that premature neurodegeneration as measured by phospho-tau (p-tau) or increased total tau (t-tau) protein may become an increasing problem. This review examines the seven human studies that have occurred over the past 14 years measuring p-tau and/or t-tau in cerebrospinal fluid (CSF) or via post-mortem brain immunohistochemistry. Although not all studies are in agreement as to the changes in p-and t-tau in HIV infected patients, HIV persists in the brain despite cART. Thus is it is suggested that those maintained on long-term cART may develop tau pathology beyond the extent seen in the studies reviewed herein and overtime may then reach the threshold for clinical manifestation.
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Affiliation(s)
| | | | | | | | | | - Brian Giunta
- Department of Molecular Pharmacology and Physiology, University of South Florida, Morsani College of Medicine, Tampa, FL 33613, USA.
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Pareek S, Roy S, Kumari B, Jain P, Banerjee A, Vrati S. MiR-155 induction in microglial cells suppresses Japanese encephalitis virus replication and negatively modulates innate immune responses. J Neuroinflammation 2014; 11:97. [PMID: 24885259 PMCID: PMC4050406 DOI: 10.1186/1742-2094-11-97] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 05/13/2014] [Indexed: 02/07/2023] Open
Abstract
Background Microglial cells, which are resident macrophages of the central nervous system, play important roles in immune responses and pathogenesis. Japanese encephalitis virus (JEV) is a neurotropic virus that infects microglial cells in brain. Several microRNAs including miR-155 and miR-146a play an important role in defining the microglia inflammatory profile. In this study, we have investigated the effect of miR-155 and miR-146a modulation on JEV infection as well as innate immune responses in human microglial cells. Methods In vitro studies were performed in JEV-infected human microglial CHME3 cells. miR-155 or miR-146a were overexpressed and total RNA and protein were extracted following JEV-infection. Expression of genes involved in innate immune responses was studied by PCR array, quantitative real-time PCR (qPCR), western blot and Fluorescence activated cell sorter (FACS). JEV replication was monitored by studying the viral RNA by qPCR, protein by western blot, and titres by plaque assay. Results Overexpression of miR-155 in CHME3 cells resulted in significantly reduced JEV replication whereas miR-146a overexpression had an insignificant effect. Additionally, interferon regulatory factor 8 (IRF8) and complement factor H (CFH) were induced during JEV infection; however, this induction was attenuated in miR-155 overexpressing cells following JEV infection. Further, JEV-induced NF-κB regulated downstream gene expression was attenuated. Interestingly, an increased level of CD45, a negative regulator of microglia activation and a reduced phosphorylated-Signal Transducers and Activators of Transcription (p-STAT1) expression was observed in miR-155 overexpressing cells upon JEV infection. Conclusion Induction of miR-155 in human microglial cells may negatively modulate JEV-induced innate immune gene expression and may have a beneficial role in limiting JEV replication in human microglial cells.
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Affiliation(s)
| | | | | | | | - Arup Banerjee
- Vaccine and Infectious Disease Research Center, Translational Health Science and Technology Institute, 496, Udyog Vihar Phase-III, Gurgaon 122016, India.
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22
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Lynch MA. The impact of neuroimmune changes on development of amyloid pathology; relevance to Alzheimer's disease. Immunology 2014; 141:292-301. [PMID: 23876085 DOI: 10.1111/imm.12156] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 07/17/2013] [Accepted: 07/18/2013] [Indexed: 12/12/2022] Open
Abstract
Neuroinflammatory changes are a characteristic of several, if not all, neurodegenerative diseases including Alzheimer's disease and are typified by increased microglial activation. Microglia express several receptors making them highly reactive and plastic cells, and, at least in vitro, they adopt different phenotypes in a manner analogous to their peripheral counterparts, macrophages. Microglia also express numerous cell surface proteins enabling them to interact with cells and the evidence indicates that maintenance of microglia in a quiescent state relies, at least to some extent, on an interaction with neurons by means of specific ligand-receptor pairs, for example CD200-CD200R. It is clear that microglia also interact with T cells and recent evidence indicates that co-incubation of microglia with T helper type 1 cells markedly increases their activation. Under normal conditions, small numbers of activated T cells gain entry to the brain and are involved in immune surveillance but infiltration of significant numbers of T cells occurs in disease and following injury. The consequences of T cell infiltration appear to depend on the conditions, with descriptions of both neurodestructive and neuroprotective effects in animal models of different diseases. This review will discuss the modulatory effect of T cells on microglia and the impact of infiltration of T cells into the brain with a focus on Alzheimer's disease, and will propose that infiltration of interferon-γ-producing cells may be an important factor in triggering inflammation that is pathogenic and destructive.
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Affiliation(s)
- Marina A Lynch
- Trinity College Institute for Neuroscience, Trinity College, Dublin, Ireland
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Galectin-1 deactivates classically activated microglia and protects from inflammation-induced neurodegeneration. Immunity 2012; 37:249-63. [PMID: 22884314 DOI: 10.1016/j.immuni.2012.05.023] [Citation(s) in RCA: 271] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 04/05/2012] [Accepted: 05/01/2012] [Indexed: 12/27/2022]
Abstract
Inflammation-mediated neurodegeneration occurs in the acute and the chronic phases of multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). Classically activated (M1) microglia are key players mediating this process. Here, we identified Galectin-1 (Gal1), an endogenous glycan-binding protein, as a pivotal regulator of M1 microglial activation that targets the activation of p38MAPK-, CREB-, and NF-κB-dependent signaling pathways and hierarchically suppresses downstream proinflammatory mediators, such as iNOS, TNF, and CCL2. Gal1 bound to core 2 O-glycans on CD45, favoring retention of this glycoprotein on the microglial cell surface and augmenting its phosphatase activity and inhibitory function. Gal1 was highly expressed in the acute phase of EAE, and its targeted deletion resulted in pronounced inflammation-induced neurodegeneration. Adoptive transfer of Gal1-secreting astrocytes or administration of recombinant Gal1 suppressed EAE through mechanisms involving microglial deactivation. Thus, Gal1-glycan interactions are essential in tempering microglial activation, brain inflammation, and neurodegeneration, with critical therapeutic implications for MS.
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Lentiviral-mediated administration of IL-25 in the CNS induces alternative activation of microglia. Gene Ther 2012; 20:487-96. [DOI: 10.1038/gt.2012.58] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Jin J, Lam L, Sadic E, Fernandez F, Tan J, Giunta B. HIV-1 Tat-induced microglial activation and neuronal damage is inhibited via CD45 modulation: A potential new treatment target for HAND. Am J Transl Res 2012; 4:302-315. [PMID: 22937208 PMCID: PMC3426392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 07/19/2012] [Indexed: 06/01/2023]
Abstract
Microglia become activated in humans subsequent to infection with HIV, and uncontrolled brain inflammation plays a key role in neuronal injury and and cognitive dysfunction during HIV infection. Various studies have shown a deleterious role for the HIV regulatory protein Tat in the development and maintenance of HIV-associated neurocognitive disorders (HAND). One cell surface receptor implicated in inhibiting microglial activation is the protein-tyrosine phosphatase (PTP), CD45. It is especially effective at inhibiting microglial activation because its action takes place far upstream from proinflammatory intracellular signaling mediators. To investigate the possible role of CD45 in microglial responsiveness to HIV-1 Tat protein, we treated BV-2 microglia with a tyrosine phosphatase inhibitor [potassium bisperoxo (1, 10-phenanthroline) oxovanadate (phen), 5 μM] and HIV-1 Tat protein (700ng/ml). We found a synergistic pro-inflammatory microglial activation as supported by tumor necrosis factor-alpha (TNF-α) and interleukin 1-beta (IL-1β) release, both of which were dependent on p44/42 mitogen-activated protein kinase (MAPK) activation. Stimulation of microglial CD45 by anti-CD45 antibody markedly inhibited these Tat or Tat/Phen effects via attenuation of p44/42 MAPK, suggesting CD45 negatively regulates microglial activation. As a validation of these findings in vivo, brains from transgenic mice deficient for CD45 through complete genetic ablation, or by CNS delivery of CD45shRNA, demonstrate markedly increased production of TNF-α 24 hours after intracerebroventricular injection of HIV-Tat protein (5μg/mouse) compared to control mice. This increased microglial activation was accompanied by astrogliosis and a significant loss of cortical neurons due to apoptosis in CD45 deficient animals. These results suggest therapeutic agents that activate CD45 PTP signaling may be effective in suppressing microglial activation associated with HAND.
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Affiliation(s)
- Jingji Jin
- Department of Psychiatry and Behavioral Neurosciences, Neuroimmunology Laboratory, University of South Florida, Morsani College of MedicineTampa, FL 33613, USA
| | - Lucy Lam
- Department of Psychiatry and Behavioral Neurosciences, Neuroimmunology Laboratory, University of South Florida, Morsani College of MedicineTampa, FL 33613, USA
| | - Edin Sadic
- Department of Psychiatry and Behavioral Neurosciences, Neuroimmunology Laboratory, University of South Florida, Morsani College of MedicineTampa, FL 33613, USA
| | - Frank Fernandez
- Department of Psychiatry and Behavioral Neurosciences, Neuroimmunology Laboratory, University of South Florida, Morsani College of MedicineTampa, FL 33613, USA
| | - Jun Tan
- Department of Psychiatry and Behavioral Neurosciences, Rashid Developmental Neurobiology Laboratory, Silver Child Development Center, University of South Florida, Morsani
- Department of Molecular Pharmacology and Physiology, University of South Florida, Morsani College of MedicineTampa, FL 33613, USA
- James A. Haley Veterans Administration HospitalTampa, FL 33612, USA
| | - Brian Giunta
- Department of Psychiatry and Behavioral Neurosciences, Neuroimmunology Laboratory, University of South Florida, Morsani College of MedicineTampa, FL 33613, USA
- Department of Molecular Pharmacology and Physiology, University of South Florida, Morsani College of MedicineTampa, FL 33613, USA
- James A. Haley Veterans Administration HospitalTampa, FL 33612, USA
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Antonelli MC, Guillemin GJ, Raisman-Vozari R, Del-Bel EA, Aschner M, Collins MA, Tizabi Y, Moratalla R, West AK. New strategies in neuroprotection and neurorepair. Neurotox Res 2011; 21:49-56. [PMID: 21861211 DOI: 10.1007/s12640-011-9265-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 07/28/2011] [Accepted: 08/03/2011] [Indexed: 12/29/2022]
Abstract
There are currently few clinical strategies in place, which provide effective neuroprotection and repair, despite an intense international effort over the past decades. One possible explanation for this is that a deeper understanding is required of how endogenous mechanisms act to confer neuroprotection. This mini-review reports the proceedings of a recent workshop "Neuroprotection and Neurorepair: New Strategies" (Iguazu Falls, Misiones, Argentina, April 11-13, 2011, Satellite Symposium of the V Neurotoxicity Society Meeting, 2011) in which four areas of active research were identified to have the potential to generate new insights into this field. Topics discussed were (i) metallothionein and other multipotent neuroprotective molecules; (ii) oxidative stress and their signal mediated pathways in neuroregeneration; (iii) neurotoxins in glial cells, and (iv) drugs of abuse with neuroprotective effects.
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Affiliation(s)
- Marta C Antonelli
- Instituto de Química y Fisicoquímica Biológicas (UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, C1113AAD, Buenos Aires, Argentina.
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