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Martínez-Larrosa J, Matute-Blanch C, Montalban X, Comabella M. Modelling multiple sclerosis using induced pluripotent stem cells. J Neuroimmunol 2020; 349:577425. [PMID: 33130461 DOI: 10.1016/j.jneuroim.2020.577425] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 10/04/2020] [Accepted: 10/12/2020] [Indexed: 01/04/2023]
Abstract
Multiple Sclerosis (MS) is one of the leading causes of non-traumatic neurological disability among young adults. Due to its complex pathology and the lack of reliable disease models, there are no effective therapies for MS to prevent neurodegeneration or promote neuroprotection, and hence stop disease progression. The emergence of induced pluripotent stem cells (iPSC) has allowed the generation of patient-specific neural cell types for disease modelling, drug screening, and cell therapy. In this review, the challenges related with the use of iPSC-derived cells in MS are discussed, with a special focus on the functional studies performed, limitations and future perspectives.
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Affiliation(s)
- Júlia Martínez-Larrosa
- Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya (Cemcat), Institut de Recerca Vall d'Hebron (VHIR), Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Clara Matute-Blanch
- Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya (Cemcat), Institut de Recerca Vall d'Hebron (VHIR), Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Xavier Montalban
- Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya (Cemcat), Institut de Recerca Vall d'Hebron (VHIR), Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Manuel Comabella
- Servei de Neurologia-Neuroimmunologia, Centre d'Esclerosi Múltiple de Catalunya (Cemcat), Institut de Recerca Vall d'Hebron (VHIR), Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain.
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102
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Hou B, Jiang C, Wang D, Wang G, Wang Z, Zhu M, Kang Y, Su J, Wei P, Ren H, Ju F. Pharmacological Targeting of CSF1R Inhibits Microglial Proliferation and Aggravates the Progression of Cerebral Ischemic Pathology. Front Cell Neurosci 2020; 14:267. [PMID: 33177990 PMCID: PMC7596178 DOI: 10.3389/fncel.2020.00267] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 07/29/2020] [Indexed: 12/11/2022] Open
Abstract
Ischemic stroke can induce rapid activation of the microglia. It has been reported that the microglia’s survival is dependent on colony-stimulating factor 1 receptor (CSF1R) signaling and that pharmacological inhibition of CSF1R leads to morphological changes in the microglia in the healthy brain. However, the impact of CSF1R inhibition on neuronal structures and motor ability after ischemia–reperfusion remains unclear. In this study, we investigated microglial de-ramification, proliferation, and activation after inhibition of CSF1R by a tyrosine kinase inhibitor (ki20227) in a mouse model of global cerebral ischemia induced by bilateral common carotid artery ligation (BCAL). In addition to microglial morphology, we evaluated the mRNA expression of cytokines, chemokines, and inflammatory receptors. Our results show that pharmacological inhibition of CSF1R in ischemic mice resulted in the blockade of microglial proliferation and a shift in microglial morphology reflected by excessive de-ramification and a more activated phenotype accompanied by an enhanced innate immune response. Furthermore, we show that pharmacological inhibition of CSF1R in ischemic mice resulted in the aggravation of neuronal degeneration and behavioral impairment. Intravital two-photon imaging revealed that although pharmacological inhibition of CSF1R did not affect the recovery of dendritic structures, it caused a significant increase in spine elimination during reperfusion in ischemic mice. These findings suggest that pharmacological inhibition of CSF1R induces a blockade of microglial proliferation and causes acute activation of the microglia accompanied by a severe inflammatory response. It aggravates neuronal degeneration, loss of dendritic spines, and behavioral deficits after transient global cerebral ischemia.
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Affiliation(s)
- Boru Hou
- Department of Neurosurgery, Lanzhou University Second Hospital, Lanzhou, China
| | - Cheng Jiang
- Department of Neurosurgery, Lanzhou University Second Hospital, Lanzhou, China
| | - Dong Wang
- Department of Neurosurgery, Lanzhou University Second Hospital, Lanzhou, China
| | - Gang Wang
- Department of Neurosurgery, Lanzhou University Second Hospital, Lanzhou, China
| | - Zening Wang
- Department of Neurosurgery, Lanzhou University Second Hospital, Lanzhou, China
| | - Miaojuan Zhu
- Second Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Yuchen Kang
- Second Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Jiacheng Su
- Second Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Pengfei Wei
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, CAS Center for Excellence in Brain Science, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Haijun Ren
- Department of Neurosurgery, Lanzhou University Second Hospital, Lanzhou, China
| | - Furong Ju
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, CAS Center for Excellence in Brain Science, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,School of Life Sciences, Lanzhou University, Lanzhou, China
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103
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York EM, Zhang J, Choi HB, MacVicar BA. Neuroinflammatory inhibition of synaptic long-term potentiation requires immunometabolic reprogramming of microglia. Glia 2020; 69:567-578. [PMID: 32946147 DOI: 10.1002/glia.23913] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 09/05/2020] [Accepted: 09/06/2020] [Indexed: 12/12/2022]
Abstract
Immunometabolism refers to the rearrangement of metabolic pathways in response to immune stimulation, and the ability of these metabolic pathways themselves to control immune functions. Many aspects of immunometabolism have been revealed through studies of peripheral immune cells. However, immunometabolic reprogramming of microglia, the resident immune cell of the central nervous system, and the consequential outcome on neuronal activity have remained difficult to unravel. Microglia are highly sensitive to subtle changes in their environment, limiting the techniques available to study their metabolic and inflammatory profiles. Here, using fluorescence lifetime imaging of endogenous NAD(P)H, we measure the metabolic activity of individual microglia within acute hippocampal slices. We observed an LPS-induced increase in aerobic glycolysis, which was blocked by the addition of 5 mM 2-deoxyglucose (2DG). This LPS-induced glycolysis in microglia was necessary for the stabilization of hypoxia inducible factor-1α (HIF-1α) and production of the proinflammatory cytokine, interleukin-1β (IL-1β). Upon release, IL-1β acted via the neuronal interleukin-1 receptor to inhibit the formation of synaptic long-term potentiation (LTP) following high frequency stimulation. Remarkably, the addition of 2DG to blunt the microglial glycolytic increase also inhibited HIF-1α accumulation and IL-1β production, and therefore rescued LTP in LPS-stimulated slices. Overall, these data reveal the importance of metabolic reprogramming in regulating microglial immune functions, with appreciable outcomes on cytokine release and neuronal activity.
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Affiliation(s)
- Elisa M York
- Djavad Mowafaghian Centre for Brain Health, Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada.,Harvard Medical School, Department of Neurobiology, Boston, Massachusetts, USA
| | - Jingfei Zhang
- Djavad Mowafaghian Centre for Brain Health, Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Hyun B Choi
- Djavad Mowafaghian Centre for Brain Health, Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian A MacVicar
- Djavad Mowafaghian Centre for Brain Health, Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
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104
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Fung S, Smith CL, Prater KE, Case A, Green K, Osnis L, Winston C, Kinoshita Y, Sopher B, Morrison RS, Garden GA, Jayadev S. Early-Onset Familial Alzheimer Disease Variant PSEN2 N141I Heterozygosity is Associated with Altered Microglia Phenotype. J Alzheimers Dis 2020; 77:675-688. [PMID: 32741831 PMCID: PMC7592656 DOI: 10.3233/jad-200492] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Early-onset familial Alzheimer disease (EOFAD) is caused by heterozygous variants in the presenilin 1 (PSEN1), presenilin 2 (PSEN2), and APP genes. Decades after their discovery, the mechanisms by which these genes cause Alzheimer's disease (AD) or promote AD progression are not fully understood. While it is established that presenilin (PS) enzymatic activity produces amyloid-β (Aβ), PSs also regulate numerous other cellular functions, some of which intersect with known pathogenic drivers of neurodegeneration. Accumulating evidence suggests that microglia, resident innate immune cells in the central nervous system, play a key role in AD neurodegeneration. OBJECTIVE Previous work has identified a regulatory role for PS2 in microglia. We hypothesized that PSEN2 variants lead to dysregulated microglia, which could further contribute to disease acceleration. To mimic the genotype of EOFAD patients, we created a transgenic mouse expressing PSEN2 N141I on a mouse background expressing one wildtype PS2 and two PS1 alleles. RESULTS Microglial expression of PSEN2 N141I resulted in impaired γ-secretase activity as well as exaggerated inflammatory cytokine release, NFκB activity, and Aβ internalization. In vivo, PS2 N141I mice showed enhanced IL-6 and TREM2 expression in brain as well as reduced branch number and length, an indication of "activated" morphology, in the absence of inflammatory stimuli. LPS intraperitoneal injection resulted in higher inflammatory gene expression in PS2 N141I mouse brain relative to controls. CONCLUSION Our findings demonstrate that PSEN2 N141I heterozygosity is associated with disrupted innate immune homeostasis, suggesting EOFAD variants may promote disease progression through non-neuronal cells beyond canonical dysregulated Aβ production.
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Affiliation(s)
- Susan Fung
- Department of Neurology, University of Washington, Seattle, WA, USA
| | - Carole L. Smith
- Department of Neurology, University of Washington, Seattle, WA, USA
| | | | - Amanda Case
- Department of Neurology, University of Washington, Seattle, WA, USA
| | - Kevin Green
- Department of Neurology, University of Washington, Seattle, WA, USA
| | - Leah Osnis
- Department of Neurology, University of Washington, Seattle, WA, USA
| | - Chloe Winston
- Department of Neurology, University of Washington, Seattle, WA, USA
| | - Yoshito Kinoshita
- Department of Neurosurgery, University of Washington, Seattle, WA, USA
| | - Bryce Sopher
- Department of Neurology, University of Washington, Seattle, WA, USA
| | | | - Gwenn A. Garden
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
| | - Suman Jayadev
- Department of Neurology, University of Washington, Seattle, WA, USA,Dr. Suman Jayadev, Department of Neurology, Box 356465, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA. Tel.: +1 206 221 2930;
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105
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Mohammed M, Thelin J, Gällentoft L, Thorbergsson PT, Kumosa LS, Schouenborg J, Pettersson LME. Ice coating -A new method of brain device insertion to mitigate acute injuries. J Neurosci Methods 2020; 343:108842. [PMID: 32628965 DOI: 10.1016/j.jneumeth.2020.108842] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/22/2020] [Accepted: 07/02/2020] [Indexed: 01/12/2023]
Abstract
BACKGROUND Reduction of insertion injury is likely important to approach physiological conditions in the vicinity of implanted devices intended to interface with the surrounding brain. NEW METHODS We have developed a novel, low-friction coating around frozen, gelatin embedded needles. By introducing a layer of thawing ice onto the gelatin, decreasing surface friction, we mitigate damage caused by the implantation. RESULTS AND COMPARISON WITH EXISTING METHODS The acute effects of a transient stab on neuronal density and glial reactions were assessed 1 and 7 days post stab in rat cortex and striatum both within and outside the insertion track using immunohistochemical staining. The addition of a coat of melting ice to the frozen gelatin embedded needles reduced the insertion force with around 50 %, substantially reduced the loss neurons (i.e. reduced neuronal void), and yielded near normal levels of astrocytes within the insertion track 1 day after insertion, as compared to gelatin coated probes of the same temperature without ice coating. There were negligible effects on glial reactions and neuronal density immediately outside the insertion track of both ice coated and cold gelatin embedded needles. This new method of implantation presents a considerable improvement compared to existing modes of device insertion. CONCLUSIONS Acute brain injuries following insertion of e.g. ultra-flexible electrodes, can be reduced by providing an outer coat of ultra-slippery thawing ice. No adverse effect of lowered implant temperature was found, opening the possibility of locking fragile electrode construct configurations in frozen gelatin, prior to implantation into the brain.
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Affiliation(s)
- Mohsin Mohammed
- Neuronano Research Center, Department of Experimental Medicine, Lund University, Lund, Sweden.
| | - Jonas Thelin
- Neuronano Research Center, Department of Experimental Medicine, Lund University, Lund, Sweden
| | - Lina Gällentoft
- Neuronano Research Center, Department of Experimental Medicine, Lund University, Lund, Sweden
| | - Palmi Thor Thorbergsson
- Neuronano Research Center, Department of Experimental Medicine, Lund University, Lund, Sweden
| | - Lucas S Kumosa
- Neuronano Research Center, Department of Experimental Medicine, Lund University, Lund, Sweden
| | - Jens Schouenborg
- Neuronano Research Center, Department of Experimental Medicine, Lund University, Lund, Sweden; NanoLund, Lund University, Professorsgatan 1, SE-223 63, Lund, Sweden
| | - Lina M E Pettersson
- Neuronano Research Center, Department of Experimental Medicine, Lund University, Lund, Sweden; NanoLund, Lund University, Professorsgatan 1, SE-223 63, Lund, Sweden.
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106
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Nakamura Y, Kimura S, Takada N, Takemura M, Iwamoto M, Hisaoka-Nakashima K, Nakata Y, Morioka N. Stimulation of toll-like receptor 4 downregulates the expression of α7 nicotinic acetylcholine receptors via histone deacetylase in rodent microglia. Neurochem Int 2020; 138:104751. [DOI: 10.1016/j.neuint.2020.104751] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/23/2020] [Accepted: 05/03/2020] [Indexed: 12/17/2022]
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107
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Pinto MV, Fernandes A. Microglial Phagocytosis-Rational but Challenging Therapeutic Target in Multiple Sclerosis. Int J Mol Sci 2020; 21:ijms21175960. [PMID: 32825077 PMCID: PMC7504120 DOI: 10.3390/ijms21175960] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 08/12/2020] [Accepted: 08/17/2020] [Indexed: 12/14/2022] Open
Abstract
Multiple sclerosis (MS) is the most common autoimmune and demyelinating disease of the central nervous system (CNS), characterized, in the majority of cases, by initial relapses that later evolve into progressive neurodegeneration, severely impacting patients’ motor and cognitive functions. Despite the availability of immunomodulatory therapies effective to reduce relapse rate and slow disease progression, they all failed to restore CNS myelin that is necessary for MS full recovery. Microglia are the primary inflammatory cells present in MS lesions, therefore strongly contributing to demyelination and lesion extension. Thus, many microglial-based therapeutic strategies have been focused on the suppression of microglial pro-inflammatory phenotype and neurodegenerative state to reduce disease severity. On the other hand, the contribution of myelin phagocytosis advocating the neuroprotective role of microglia in MS has been less explored. Indeed, despite the presence of functional oligodendrocyte precursor cells (OPCs), within lesioned areas, MS plaques fail to remyelinate as a result of the over-accumulation of myelin-toxic debris that must be cleared away by microglia. Dysregulation of this process has been associated with the impaired neuronal recovery and deficient remyelination. In line with this, here we provide a comprehensive review of microglial myelin phagocytosis and its involvement in MS development and repair. Alongside, we discuss the potential of phagocytic-mediated therapeutic approaches and encourage their modulation as a novel and rational approach to ameliorate MS-associated pathology.
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Affiliation(s)
- Maria V. Pinto
- Neuron-Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal;
| | - Adelaide Fernandes
- Neuron-Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal;
- Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal
- Correspondence: ; Tel.: +351-217946400
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108
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Jurga AM, Paleczna M, Kuter KZ. Overview of General and Discriminating Markers of Differential Microglia Phenotypes. Front Cell Neurosci 2020; 14:198. [PMID: 32848611 PMCID: PMC7424058 DOI: 10.3389/fncel.2020.00198] [Citation(s) in RCA: 491] [Impact Index Per Article: 122.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 06/05/2020] [Indexed: 12/12/2022] Open
Abstract
Inflammatory processes and microglia activation accompany most of the pathophysiological diseases in the central nervous system. It is proven that glial pathology precedes and even drives the development of multiple neurodegenerative conditions. A growing number of studies point out the importance of microglia in brain development as well as in physiological functioning. These resident brain immune cells are divergent from the peripherally infiltrated macrophages, but their precise in situ discrimination is surprisingly difficult. Microglial heterogeneity in the brain is especially visible in their morphology and cell density in particular brain structures but also in the expression of cellular markers. This often determines their role in physiology or pathology of brain functioning. The species differences between rodent and human markers add complexity to the whole picture. Furthermore, due to activation, microglia show a broad spectrum of phenotypes ranging from the pro-inflammatory, potentially cytotoxic M1 to the anti-inflammatory, scavenging, and regenerative M2. A precise distinction of specific phenotypes is nowadays essential to study microglial functions and tissue state in such a quickly changing environment. Due to the overwhelming amount of data on multiple sets of markers that is available for such studies, the choice of appropriate markers is a scientific challenge. This review gathers, classifies, and describes known and recently discovered protein markers expressed by microglial cells in their different phenotypes. The presented microglia markers include qualitative and semi-quantitative, general and specific, surface and intracellular proteins, as well as secreted molecules. The information provided here creates a comprehensive and practical guide through the current knowledge and will facilitate the choosing of proper, more specific markers for detailed studies on microglia and neuroinflammatory mechanisms in various physiological as well as pathological conditions. Both basic research and clinical medicine need clearly described and validated molecular markers of microglia phenotype, which are essential in diagnostics, treatment, and prevention of diseases engaging glia activation.
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Affiliation(s)
- Agnieszka M Jurga
- Maj Institute of Pharmacology, Department of Neuropsychopharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Martyna Paleczna
- Maj Institute of Pharmacology, Department of Neuropsychopharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Katarzyna Z Kuter
- Maj Institute of Pharmacology, Department of Neuropsychopharmacology, Polish Academy of Sciences, Krakow, Poland
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109
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Sugama S, Kakinuma Y. Stress and brain immunity: Microglial homeostasis through hypothalamus-pituitary-adrenal gland axis and sympathetic nervous system. Brain Behav Immun Health 2020; 7:100111. [PMID: 34589871 PMCID: PMC8474505 DOI: 10.1016/j.bbih.2020.100111] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 07/09/2020] [Accepted: 07/19/2020] [Indexed: 01/03/2023] Open
Abstract
Stress has been well documented to bring about various clinical disorders, ranging from neurodegeneration, such as Parkinson’s (PD) and Alzheimer’s diseases (AD), to metabolic disorders including diabetes mellitus. Importantly, microglia, immunocompetent cells in the brain, have been shown to be involved in these clinical disorders. In the recent studies aiming to clarify the microglial responses, microglia are found to be quite responsive to stressful events, such as acute, subchronic, chronic stress, and social defeat stress. However, the mechanisms of these stress response on microglial activation have been not fully understood. In response to stress exposure, both the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS) are simultaneously activated, with the former inducing glucocorticoids (GCs) and the latter noradrenaline (NA), respectively. However, the effects of these stress-induced GCs and NA have not been consistent. The GCs, conventionally known to act on microglia as immunosuppressant, is also reported to act on it as stimulator. Similarly, the NA has been reported to act on microglia as stimulator or inhibitor depending on environmental conditions. Since any kinds of stress upregulate the HPA axis and SNS, with the levels of upregulation variable depending on the stress type, it is plausible that microglia is closely regulated by these two stress pathways. In this review, we discuss the microglial responses induced by various stresses as well as the possible mechanism by which stress induces microglial activation. The present study introduces the mechanism by which microglial activation occurs following acute stress. The present study suggests that microglial activation may be regulated through the HPA axis and sympathetic nervous system. The present study suggests that microglia may be inhibited by glucocorticoids, while activated by noradrenaline under physiological conditions. The present study suggests the hypothesis that the HPA axis may interact with sympathetic nervous system to maintain microglial homeostasis.
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110
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Polysialic acid and Siglec-E orchestrate negative feedback regulation of microglia activation. Cell Mol Life Sci 2020; 78:1637-1653. [PMID: 32725371 PMCID: PMC7904730 DOI: 10.1007/s00018-020-03601-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 06/23/2020] [Accepted: 07/17/2020] [Indexed: 11/09/2022]
Abstract
Polysialic acid (polySia) emerges as a novel regulator of microglia activity. We recently identified polysialylated proteins in the Golgi compartment of murine microglia that are released in response to inflammatory stimulation. Since exogenously added polySia is able to attenuate the inflammatory response, we proposed that the release of polysialylated proteins constitutes a mechanism for negative feedback regulation of microglia activation. Here, we demonstrate that translocation of polySia from the Golgi to the cell surface can be induced by calcium depletion of the Golgi compartment and that polysialylated proteins are continuously released for at least 24 h after the onset of inflammatory stimulation. The latter was unexpected, because polySia signals detected by immunocytochemistry are rapidly depleted. However, it indicates that the amount of released polySia is much higher than anticipated based on immunostaining. This may be crucial for microglial responses during traumatic brain injury (TBI), as we detected polySia signals in activated microglia around a stab wound in the adult mouse brain. In BV2 microglia, the putative polySia receptor Siglec-E is internalized during lipopolysaccharide (LPS)-induced activation and in response to polySia exposure, indicating interaction. Correspondingly, CRISPR/Cas9-mediated Siglec-E knockout prevents inhibition of pro inflammatory activation by exogenously added polySia and leads to a strong increase of the LPS response. A comparable increase of LPS-induced activation has been observed in microglia with abolished polySia synthesis. Together, these results indicate that the release of the microglia-intrinsic polySia pool, as implicated in TBI, inhibits the inflammatory response by acting as a trans-activating ligand of Siglec-E.
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111
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Edison P. Neuroinflammation, microglial activation, and glucose metabolism in neurodegenerative diseases. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2020; 154:325-344. [PMID: 32739010 DOI: 10.1016/bs.irn.2020.03.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Alzheimer's disease is characterized by aggregated amyloid beta plaques and neurofibrillary tangles. Apart from the plaques and tangles, microglial activation plays a significant role in neurodegeneration and neuronal function. This review discusses the way in which microglial activation influences neurodegeneration and how systemic inflammation, type 2 diabetes mellitus, obesity and hypercholesterolemia influence neuroinflammation. Also reviewed is how systemic inflammation influences microglial activation along with the relationship between microglial activation and glucose metabolism.
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Affiliation(s)
- Paul Edison
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom; Cardiff University, Cardiff, United Kingdom.
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112
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Abstract
Microglia are the major immune cells in the central nervous system and play a key role in the normal function of the brain. Microglia exhibit functional diversity, and they control the inflammation in central nervous system through releasing inflammatory cytokine, clearing apoptotic cells via phagocytosis, regulating synaptic plasticity and the formation of neural network by synapse pruning. Recent studies have strongly indicated that the microglial dysfunction is associated with a variety of neuropsychiatric diseases such as depression, which have been termed as "microgliopathy". The emergency of advanced technologies and tools has enabled us to comprehensively understand the role of microglia in physiology and pathology, and growing studies have targetted microglia to explore the treatment of neuropsychiatric diseases. Here, we describe the key progress of microglia research, and review the recent developments in the understanding of the role of microglia in physiology and etiology of depression.
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113
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Quantitative immunohistochemical analysis of myeloid cell marker expression in human cortex captures microglia heterogeneity with anatomical context. Sci Rep 2020; 10:11693. [PMID: 32678124 PMCID: PMC7366669 DOI: 10.1038/s41598-020-68086-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 06/12/2020] [Indexed: 12/14/2022] Open
Abstract
Current immunohistochemical methods of studying microglia in the post-mortem human brain do not capture the heterogeneity of microglial function in response to damage and disease. We therefore investigated the expression of eight myeloid cell proteins associated with changes in function alongside Iba1. To study the myeloid cells we used immunohistochemistry on post-mortem human middle temporal gyrus sections from neurologically normal individuals. First we investigated co-labelling between the classical 'activation' marker, HLA-DR and each of the other markers of interest. Significant co-labelling between HLA-DR with CD206, CD32, CD163, or L-Ferritin was observed, although complete overlap of expression of HLA-DR with aforementioned markers was not observed. A qualitative assessment also demonstrated that perivascular macrophages expressed higher levels of the markers of interest we investigated than microglia, suggesting perivascular macrophages show a more phagocytic and antigen presentation state in the human brain. To determine whether the markers of interest were expressed in different functional states, the immunoreactivity for each marker was qualitatively assessed on microglial morphologies. Degenerating marker, L-Ferritin, was specific for dystrophic microglia. We demonstrate that microglial heterogeneity can be investigated in immunohistochemically stain post-mortem human tissue by integrating the single-cell abundance of proteins and cell morphology to infer function.
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114
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Chunchai T, Keawtep P, Arinno A, Saiyasit N, Prus D, Apaijai N, Pratchayasakul W, Chattipakorn N, Chattipakorn SC. N-acetyl cysteine, inulin and the two as a combined therapy ameliorate cognitive decline in testosterone-deprived rats. Aging (Albany NY) 2020; 11:3445-3462. [PMID: 31160542 PMCID: PMC6594791 DOI: 10.18632/aging.101989] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/20/2019] [Indexed: 12/13/2022]
Abstract
Our previous studies reported that testosterone-deprived rats developed cognitive decline as a result of increased brain oxidative stress, microglia hyperactivity, and hippocampal dysplasticity. In addition, gut dysbiosis occurred in these rats. Previous studies demonstrated that n-acetyl cysteine (NAC) and a prebiotic (inulin) improved cognition in several pathological conditions. However, its effects on cognition in the testosterone-deprived condition have never been investigated. This study hypothesized that the administration of NAC, inulin, and a combined therapy improved cognition in castrated rats. Here we report that metabolic disturbance was not observed in the ORX rats, but gut dysbiosis was found in these rats. ORX rats developed blood-brain-barrier (BBB) breakdown, and increased brain oxidative stress as indicated by increased hippocampal production of reactive oxygen species (ROS) and an increase in brain malondialdehyde level. ORX rats also demonstrated glia hyperactivation, resulting in hippocampal apoptosis, hippocampal dysplasticity, and cognitive decline. All treatments equally ameliorated cognitive decline by improving gut dysbiosis, alleviating BBB dysfunction, decreasing hippocampal ROS production, decreasing hippocampal apoptosis, and reducing microglia and astrocyte activity. These findings suggest that NAC, inulin, and the combined therapy ameliorated the deleterious effects on the brain in castrated male rats similar to those treated with testosterone.
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Affiliation(s)
- Titikorn Chunchai
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Cardiac Electrophysiology Unit, Department of Physiology Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Puntarik Keawtep
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Cardiac Electrophysiology Unit, Department of Physiology Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Apiwan Arinno
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Cardiac Electrophysiology Unit, Department of Physiology Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Napatsorn Saiyasit
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Cardiac Electrophysiology Unit, Department of Physiology Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Dillon Prus
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Nattayaporn Apaijai
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Cardiac Electrophysiology Unit, Department of Physiology Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Wasana Pratchayasakul
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Cardiac Electrophysiology Unit, Department of Physiology Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Nipon Chattipakorn
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Cardiac Electrophysiology Unit, Department of Physiology Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Siriporn C Chattipakorn
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.,Department of Oral Biology and Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai 50200, Thailand
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115
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Zhang C, Frye MD, Sun W, Sharma A, Manohar S, Salvi R, Hu BH. New insights on repeated acoustic injury: Augmentation of cochlear susceptibility and inflammatory reaction resultant of prior acoustic injury. Hear Res 2020; 393:107996. [PMID: 32534268 DOI: 10.1016/j.heares.2020.107996] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 04/29/2020] [Accepted: 05/12/2020] [Indexed: 12/20/2022]
Abstract
In industrial and military settings, individuals who suffer from one episode of acoustic trauma are likely to sustain another episode of acoustic stress, creating an opportunity for a potential interaction between the two stress conditions. We previously demonstrated that acoustic overstimulation perturbs the cochlear immune environment. However, how the cochlear immune system responds to repeated acoustic overstimulation is unknown. Here, we used a mouse model to investigate the cochlear immune response to repeated stress. We reveal that exposure to an intense noise at 120 dB SPL for 1 h activates the cochlear immune response in a time-dependent fashion with substantial expansion and activation of the macrophage population in the cochlea at 2-days post-exposure. At 20-days post-exposure, the number and pro-inflammatory phenotypes of cochlear macrophages have significantly subsided, but have yet to return to homeostatic levels. Monocytes with anti-inflammatory phenotypes are recruited into the cochlea. With the presence of this residual immune activation, a second exposure to the same noise provokes an exaggerated inflammatory response as evidenced by exacerbated maturation of macrophages. Furthermore, the second noise causes greater sensory cell pathogenesis. Unlike the first noise-induced damage that occurs mainly between 0 and 2 days post-exposure, the second noise-induced damage occurs more frequently between 2 and 20 days post-exposure, the period when secondary damage takes place. These observations suggest that repeated acoustic overstimulation exacerbates cochlear inflammation and secondary sensory cell pathogenesis. Together, our results suggest that the cochlear immune system plays an important role in modulating cochlear responses to repeated acoustic stress.
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Affiliation(s)
- Celia Zhang
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY, 14214, USA.
| | - Mitchell D Frye
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY, 14214, USA.
| | - Wei Sun
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY, 14214, USA.
| | - Ashu Sharma
- Department of Oral Biology, University at Buffalo, School of Dental Medicine, University of Buffalo, The State University of New York, Buffalo, NY, USA, 14214.
| | - Senthilvelan Manohar
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY, 14214, USA.
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY, 14214, USA.
| | - Bo Hua Hu
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY, 14214, USA.
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116
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Rotterman TM, Alvarez FJ. Microglia Dynamics and Interactions with Motoneurons Axotomized After Nerve Injuries Revealed By Two-Photon Imaging. Sci Rep 2020; 10:8648. [PMID: 32457369 PMCID: PMC7250868 DOI: 10.1038/s41598-020-65363-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 05/01/2020] [Indexed: 01/08/2023] Open
Abstract
The significance of activated microglia around motoneurons axotomized after nerve injuries has been intensely debated. In particular, whether microglia become phagocytic is controversial. To resolve these issues we directly observed microglia behaviors with two-photon microscopy in ex vivo spinal cord slices from CX3CR1-GFP mice complemented with confocal analyses of CD68 protein. Axotomized motoneurons were retrogradely-labeled from muscle before nerve injuries. Microglia behaviors close to axotomized motoneurons greatly differ from those within uninjured motor pools. They develop a phagocytic phenotype as early as 3 days after injury, characterized by frequent phagocytic cups, high phagosome content and CD68 upregulation. Interactions between microglia and motoneurons changed with time after axotomy. Microglia first extend processes that end in phagocytic cups at the motoneuron surface, then they closely attach to the motoneuron while extending filopodia over the cell body. Confocal 3D analyses revealed increased microglia coverage of the motoneuron cell body surface with time after injury and the presence of CD68 granules in microglia surfaces opposed to motoneurons. Some microglia formed macroclusters associated with dying motoneurons. Microglia in these clusters display the highest CD68 expression and associate with cytotoxic T-cells. These observations are discussed in relation to current theories on microglia function around axotomized motoneurons.
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Affiliation(s)
- Travis M Rotterman
- Department of Physiology, Emory University, Atlanta, GA, 30322, United States of America.,School of Biological Sciences, Georgia Tech, Atlanta, GA, 30318, United States of America
| | - Francisco J Alvarez
- Department of Physiology, Emory University, Atlanta, GA, 30322, United States of America.
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117
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Prinz M, Jung S, Priller J. Microglia Biology: One Century of Evolving Concepts. Cell 2020; 179:292-311. [PMID: 31585077 DOI: 10.1016/j.cell.2019.08.053] [Citation(s) in RCA: 750] [Impact Index Per Article: 187.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 08/08/2019] [Accepted: 08/27/2019] [Indexed: 01/05/2023]
Abstract
Microglia were first recognized as a distinct cell population in the CNS one century ago. For a long time, they were primarily considered to be phagocytes responsible for removing debris during CNS development and disease. More recently, advances in imaging and genetics and the advent of single-cell technologies provided new insights into the much more complex and fascinating biology of microglia. The ontogeny of microglia was identified, and their functions in health and disease were better defined. Although many questions about microglia and their roles in human diseases remain unanswered, the prospect of targeting microglia for the treatment of neurological and psychiatric disorders is tantalizing.
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Affiliation(s)
- Marco Prinz
- Institute of Neuropathology, Medical Faculty, University of Freiburg, Freiburg, Germany; Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany; Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany.
| | - Steffen Jung
- Department of Immunology, Weizmann Institute of Science, Rehovot 76100, Israel.
| | - Josef Priller
- Department of Neuropsychiatry and Laboratory of Molecular Psychiatry, Charité - Universitätsmedizin Berlin, Berlin, Germany; DZNE and BIH, Berlin, Germany; University of Edinburgh and UK DRI, Edinburgh, UK.
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118
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Fruits and leaves from wild blueberry plants contain diverse polyphenols and decrease neuroinflammatory responses in microglia. J Funct Foods 2020. [DOI: 10.1016/j.jff.2020.103906] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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119
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Di Marco S, Riccitelli S, Di Paolo M, Campos E, Buzzi M, Bisti S, Versura P. Cord Blood Serum (CBS)-Based Eye Drops Modulate Light-Induced Neurodegeneration in Albino Rat Retinas. Biomolecules 2020; 10:biom10050678. [PMID: 32354031 PMCID: PMC7277721 DOI: 10.3390/biom10050678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 04/19/2020] [Accepted: 04/24/2020] [Indexed: 12/13/2022] Open
Abstract
Age-related macular degeneration (AMD) is one of the leading causes of visual loss in western countries, it has no cure, and its incidence will grow in the future, for the overall population aging. Albino rats with retinal degeneration induced by exposure to high-intensity light (light-damage, LD) have been extensively used as a model of AMD to test neuroprotective agents. Among them, trophic factors (NGF and BDNF) have been shown to play a significant role in photoreceptors' survival. Interestingly, cord blood serum (CBS) is an extract full of chemokines and trophic factors; we, therefore, hypothesized that CBS could be an excellent candidate for neuroprotection. Here, we investigate whether CBS-based eye drops might mitigate the effects of light-induced retinal degeneration in albino rats. CBS treatment significantly preserved flash-electroretinogram (f-ERG) response after LD and reduced the "hot-spot" extension. Besides, CBS-treated animals better preserved the morphology of the outer nuclear layer, together with a reduction in microglia migration and activation. Interestingly, the treatment did not modulate reactive gliosis and activation of the self-protective mechanism (FGF2). In conclusion, our results suggest that CBS-based eye drops might be successfully used to mitigate retinal neurodegenerative processes such as AMD.
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Affiliation(s)
- Stefano Di Marco
- Department of Applied Clinical Science and Biotechnology, University of L’Aquila, Via Vetoio, Coppito II, 67100 L’Aquila, Italy
- Istituto Nazionale di Biostrutture e Biosistemi (INBB), Via Medaglie d’Oro 305, 00136 Roma, Italy
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Largo Rosanna Benzi, 16132 Genova, Italy
- IRCCS, Ospedale Policlinico San Martino, Largo Rosanna Benzi, 16132 Genova, Italy
- Correspondence: (S.D.M.); (S.B.)
| | - Serena Riccitelli
- Department of Applied Clinical Science and Biotechnology, University of L’Aquila, Via Vetoio, Coppito II, 67100 L’Aquila, Italy
| | - Mattia Di Paolo
- Department of Applied Clinical Science and Biotechnology, University of L’Aquila, Via Vetoio, Coppito II, 67100 L’Aquila, Italy
| | - Emilio Campos
- Ophthalmology Unit, University of Bologna and S. Orsola-Malpighi Teaching Hospital, 40138 Bologna, Italy
| | - Marina Buzzi
- Emilia Romagna, Cord Blood Bank-Transfusion Service, S. Orsola-Malpighi Teaching Hospital, 40138 Bologna, Italy
| | - Silvia Bisti
- Department of Applied Clinical Science and Biotechnology, University of L’Aquila, Via Vetoio, Coppito II, 67100 L’Aquila, Italy
- Istituto Nazionale di Biostrutture e Biosistemi (INBB), Via Medaglie d’Oro 305, 00136 Roma, Italy
- NetS3 Laboratory, Istituto Italiano di Tecnologia, Via Morego, 30, 16163 Genova, Italy
- Correspondence: (S.D.M.); (S.B.)
| | - Piera Versura
- Ophthalmology Unit, University of Bologna and S. Orsola-Malpighi Teaching Hospital, 40138 Bologna, Italy
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120
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Yuan C, Aierken A, Xie Z, Li N, Zhao J, Qing H. The age-related microglial transformation in Alzheimer's disease pathogenesis. Neurobiol Aging 2020; 92:82-91. [PMID: 32408056 DOI: 10.1016/j.neurobiolaging.2020.03.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/11/2020] [Accepted: 03/31/2020] [Indexed: 12/15/2022]
Abstract
Neuroinflammatory responses mediated by microglia, the resident immune cells of the central nervous system, have long been a subject of study in the field of Alzheimer's disease (AD). Microglia express a wide range of receptors that act as molecular sensors, through which they can fulfill their various functions. In this review, we first analyzed the changes in the expression levels of microglial membrane receptors SR-A, TREM2, CD36, CD33, and CR3 in aging and AD and described the different roles of these receptors in amyloid-beta clearance and inflammatory responses. Two classical hallmarks of AD are extracellular amyloid-beta deposits and intracellular aggregated phosphorylated tau. In AD, microglia reaction was initially thought to be triggered by amyloid deposits. New evidence showed it also associated with increased phosphorylation of tau. However, which first appeared and induced activated microglia is not clear. Then we summarized diverse opinions on it. Besides, as AD is tightly linked to aging, and microglia changes dramatically on aging, yet the relative impacts of both aging and microglia are less frequently considered, so at last, we discussed the roles of aging microglia in AD. We hope to provide a reference for subsequent research.
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Affiliation(s)
- Chunxu Yuan
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biological Sciences, School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Ailikemu Aierken
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biological Sciences, School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Zhen Xie
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biological Sciences, School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Nuomin Li
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biological Sciences, School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Juan Zhao
- School of Materials Science and Engineering, Department of Materials Processing Engineering, Beijing Institute of Technology, Beijing, China.
| | - Hong Qing
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biological Sciences, School of Life Science, Beijing Institute of Technology, Beijing, China.
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121
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LeBlang CJ, Medalla M, Nicoletti NW, Hays EC, Zhao J, Shattuck J, Cruz AL, Wolozin B, Luebke JI. Reduction of the RNA Binding Protein TIA1 Exacerbates Neuroinflammation in Tauopathy. Front Neurosci 2020; 14:285. [PMID: 32327969 PMCID: PMC7161592 DOI: 10.3389/fnins.2020.00285] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 03/12/2020] [Indexed: 12/13/2022] Open
Abstract
Neuroinflammatory processes play an integral role in the exacerbation and progression of pathology in tauopathies, a class of neurodegenerative disease characterized by aggregation of hyperphosphorylated tau protein. The RNA binding protein (RBP) T-cell Intracellular Antigen 1 (TIA1) is an important regulator of the innate immune response in the periphery, dampening cytotoxic inflammation and apoptosis during cellular stress, however, its role in neuroinflammation is unknown. We have recently shown that TIA1 regulates tau pathophysiology and toxicity in part through the binding of phospho-tau oligomers into pathological stress granules, and that haploinsufficiency of TIA1 in the P301S mouse model of tauopathy results in reduced accumulation of toxic tau oligomers, pathologic stress granules, and the development of downstream pathological features of tauopathy. The putative role of TIA1 as a regulator of the peripheral immune response led us to investigate the effects of TIA1 on neuroinflammation in the context of tauopathy, a chronic stressor in the neural environment. Here, we evaluated indicators of neuroinflammation including; reactive microgliosis and phagocytosis, pro-inflammatory cytokine release, and oxidative stress in hippocampal neurons and glia of wildtype and P301S transgenic mice expressing TIA1+/+, TIA1+/-, and TIA1-/- in both early (5 month) and advanced (9 month) disease states through biochemical, ultrastructural, and histological analyses. Our data show that both TIA1 haploinsufficiency and TIA1 knockout exacerbate neuroinflammatory processes in advanced stages of tauopathy, suggesting that TIA1 dampens the immune response in the central nervous system during chronic stress.
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Affiliation(s)
- Chelsey Jenna LeBlang
- Laboratory of Cellular Neuroscience, Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, United States
| | - Maria Medalla
- Laboratory of Cellular Neuroscience, Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, United States
| | - Nicholas William Nicoletti
- Laboratory of Cellular Neuroscience, Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, United States
| | - Emma Catherine Hays
- Laboratory of Cellular Neuroscience, Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, United States
| | - James Zhao
- Laboratory of Cellular Neuroscience, Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, United States
| | - Jenifer Shattuck
- Laboratory of Neurodegeneration, Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
| | - Anna Lourdes Cruz
- Laboratory of Neurodegeneration, Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
| | - Benjamin Wolozin
- Laboratory of Neurodegeneration, Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
- Department of Neurology, Boston University School of Medicine, Boston, MA, United States
- Department of Neuroscience, Boston University, Boston, MA, United States
| | - Jennifer Irene Luebke
- Laboratory of Cellular Neuroscience, Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, United States
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122
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Neuronal mitochondria-targeted micelles relieving oxidative stress for delayed progression of Alzheimer's disease. Biomaterials 2020; 238:119844. [DOI: 10.1016/j.biomaterials.2020.119844] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 02/03/2020] [Accepted: 02/03/2020] [Indexed: 12/21/2022]
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123
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Mariani MM, Mojziszek K, Curley E, Thornton JE. Lowering luteinizing hormone (LH) reverses spatial memory deficits associated with neurotoxin infusion into the hippocampus of ovx rats. Horm Behav 2020; 119:104631. [PMID: 31759942 DOI: 10.1016/j.yhbeh.2019.104631] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 10/24/2019] [Accepted: 10/28/2019] [Indexed: 01/14/2023]
Affiliation(s)
- Monica M Mariani
- Neuroscience Department, Oberlin College, 119 Woodland Street, Oberlin, OH 44074, USA.
| | - Kirsten Mojziszek
- Neuroscience Department, Oberlin College, 119 Woodland Street, Oberlin, OH 44074, USA
| | - Emily Curley
- Neuroscience Department, Oberlin College, 119 Woodland Street, Oberlin, OH 44074, USA
| | - Janice E Thornton
- Neuroscience Department, Oberlin College, 119 Woodland Street, Oberlin, OH 44074, USA
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124
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Xu S, Lu J, Shao A, Zhang JH, Zhang J. Glial Cells: Role of the Immune Response in Ischemic Stroke. Front Immunol 2020; 11:294. [PMID: 32174916 PMCID: PMC7055422 DOI: 10.3389/fimmu.2020.00294] [Citation(s) in RCA: 307] [Impact Index Per Article: 76.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 02/05/2020] [Indexed: 12/16/2022] Open
Abstract
Ischemic stroke, which accounts for 75-80% of all strokes, is the predominant cause of morbidity and mortality worldwide. The post-stroke immune response has recently emerged as a new breakthrough target in the treatment strategy for ischemic stroke. Glial cells, including microglia, astrocytes, and oligodendrocytes, are the primary components of the peri-infarct environment in the central nervous system (CNS) and have been implicated in post-stroke immune regulation. However, increasing evidence suggests that glial cells exert beneficial and detrimental effects during ischemic stroke. Microglia, which survey CNS homeostasis and regulate innate immune responses, are rapidly activated after ischemic stroke. Activated microglia release inflammatory cytokines that induce neuronal tissue injury. By contrast, anti-inflammatory cytokines and neurotrophic factors secreted by alternatively activated microglia are beneficial for recovery after ischemic stroke. Astrocyte activation and reactive gliosis in ischemic stroke contribute to limiting brain injury and re-establishing CNS homeostasis. However, glial scarring hinders neuronal reconnection and extension. Neuroinflammation affects the demyelination and remyelination of oligodendrocytes. Myelin-associated antigens released from oligodendrocytes activate peripheral T cells, thereby resulting in the autoimmune response. Oligodendrocyte precursor cells, which can differentiate into oligodendrocytes, follow an ischemic stroke and may result in functional recovery. Herein, we discuss the mechanisms of post-stroke immune regulation mediated by glial cells and the interaction between glial cells and neurons. In addition, we describe the potential roles of various glial cells at different stages of ischemic stroke and discuss future intervention targets.
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Affiliation(s)
- Shenbin Xu
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jianan Lu
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Anwen Shao
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - John H Zhang
- Department of Physiology and Pharmacology, School of Medicine, Loma Linda University, Loma Linda, CA, United States.,Department of Anesthesiology, School of Medicine, Loma Linda University, Loma Linda, CA, United States.,Department of Neurosurgery, School of Medicine, Loma Linda University, Loma Linda, CA, United States
| | - Jianmin Zhang
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Brain Research Institute, Zhejiang University, Hangzhou, China.,Collaborative Innovation Center for Brain Science, Zhejiang University, Hangzhou, China
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125
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Tomita N, Nakamura T, Sunden Y, Miyata H, Morita T. Temporal analysis of histopathology and cytokine expression in the rat cerebral cortex after insulin-induced hypoglycemia. Neuropathology 2020; 40:240-250. [PMID: 32080930 DOI: 10.1111/neup.12643] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/24/2019] [Accepted: 12/25/2019] [Indexed: 11/30/2022]
Abstract
Hypoglycemic coma causes neuronal death in the cerebral neocortex; however, its unclear pathogenesis prevents the establishment of preventive measures. Inflammation plays a pivotal role in neuronal damage in the hypoglycemic state; however, the dynamics of glial cell activation or cytokine expression remain unknown. Here, we aimed to elucidate the spatiotemporal morphological changes of microglia and time-course cytokine expression profiles in the rat cerebral cortex after hypoglycemic coma. We performed histopathological and immunohistochemical (Iba1, neuronal nuclei, glial fibrillary acidic protein) analyses in the cingulate cortex and four areas of the neocortex: hindlimb area (HL), parietal cortex area 1 (Par1), parietal cortex area 2 (Par2), and perirhinal cortex (PRh). We measured tumor necrosis factor alpha (TNFα) and interleukin-6 messenger RNA (mRNA) expression by real-time reverse transcriptase-polymerase chain reaction. Necrotic neurons appeared in the neocortex as early as 3 h after hypoglycemic coma, while they were absent in the cingulate cortex. Neuronal nuclei-immunopositive neurons in the HL, Par2, and PRh were significantly less abundant than in the control at day 1. In Iba1 immunostaining, large rod-shaped cells were detected at 3-6 h after hypoglycemia, and commonly observed in the HL, Par2, and PRh. After 6 h, rod-shaped cells were rarely observed; instead, there was a prominent infiltration of hypertrophic and ameboid-shaped cells until day 7. The mRNA expression of TNFα was significantly higher than the control at 3-6 h after hypoglycemia in the neocortex, while it was significantly higher only at 3 h in the cingulate cortex. Our results indicate that early and transient appearance of rod-shaped microglia and persisting high TNFα expression levels characterize inflammatory responses to hypoglycemic neuronal damage in the cerebral neocortex, which might contribute to neuronal necrosis in response to transient hypoglycemic coma.
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Affiliation(s)
- Nagi Tomita
- Laboratory of Veterinary Pathology, Tottori University, Tottori, Japan.,The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan
| | - Tomoki Nakamura
- Laboratory of Veterinary Pathology, Tottori University, Tottori, Japan
| | - Yuji Sunden
- Laboratory of Veterinary Pathology, Tottori University, Tottori, Japan
| | - Hajime Miyata
- Department of Neuropathology, Research Institute for Brain and Blood Vessels, Akita Cerebrospinal and Cardiovascular Center, Akita, Japan
| | - Takehito Morita
- Laboratory of Veterinary Pathology, Tottori University, Tottori, Japan
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126
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Holmkvist AD, Agorelius J, Forni M, Nilsson UJ, Linsmeier CE, Schouenborg J. Local delivery of minocycline-loaded PLGA nanoparticles from gelatin-coated neural implants attenuates acute brain tissue responses in mice. J Nanobiotechnology 2020; 18:27. [PMID: 32024534 PMCID: PMC7003334 DOI: 10.1186/s12951-020-0585-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 01/27/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Neural interfaces often elicit inflammatory responses and neuronal loss in the surrounding tissue which adversely affect the function and longevity of the implanted device. Minocycline, an anti-inflammatory pharmaceutics with neuroprotective properties, may be used for reducing the acute brain tissue responses after implantation. However, conventional administration routes require high doses which can cause adverse systemic side effects. Therefore, the aim of this study was to develop and evaluate a new drug-delivery-system for local and sustained administration of minocycline in the brain. METHODS Stainless steel needles insulated with Parylene-C were dip-coated with non-crosslinked gelatin and minocycline-loaded PLGA nanoparticles (MC-NPs) were incorporated into the gelatin-coatings by an absorption method and subsequently trapped by drying the gelatin. Parylene-C insulated needles coated only with gelatin were used as controls. The expression of markers for activated microglia (CD68), all microglia (CX3CR1-GFP), reactive astrocytes (GFAP), neurons (NeuN) and all cell nuclei (DAPI) surrounding the implantation sites were quantified at 3 and 7 days after implantation in mice. RESULTS MC-NPs were successfully incorporated into gelatin-coatings of neural implants by an absorption method suitable for thermosensitive drug-loads. Immunohistochemical analysis of the in vivo brain tissue responses, showed that MC-NPs significantly attenuate the activation of microglial cells without effecting the overall population of microglial cells around the implantation sites. A delayed but significant reduction of the astrocytic response was also found in comparison to control implants. No effect on neurons or total cell count was found which may suggest that the MC-NPs are non-toxic to the central nervous system. CONCLUSIONS A novel drug-nanoparticle-delivery-system was developed for neural interfaces and thermosensitive drug-loads. The local delivery of MC-NPs was shown to attenuate the acute brain tissue responses nearby an implant and therefore may be useful for improving biocompatibility of implanted neuro-electronic interfaces. The developed drug-delivery-system may potentially also be used for other pharmaceutics to provide highly localized and therefore more specific effects as compared to systemic administration.
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Affiliation(s)
- Alexander Dontsios Holmkvist
- Neuronano Research Center, Department of Experimental Medical Science, Faculty of Medicine, Lund University, Medicon Village, Building 404 A2, Scheelevägen 2, 223 81, Lund, Sweden. .,Centre for Analysis and Synthesis, Department of Chemistry, Lund University, Box 124, 221 00, Lund, Sweden.
| | - Johan Agorelius
- Neuronano Research Center, Department of Experimental Medical Science, Faculty of Medicine, Lund University, Medicon Village, Building 404 A2, Scheelevägen 2, 223 81, Lund, Sweden.,NanoLund, Lund University, Professorsgatan 1, 223 63, Lund, Sweden
| | - Matilde Forni
- Neuronano Research Center, Department of Experimental Medical Science, Faculty of Medicine, Lund University, Medicon Village, Building 404 A2, Scheelevägen 2, 223 81, Lund, Sweden
| | - Ulf J Nilsson
- Centre for Analysis and Synthesis, Department of Chemistry, Lund University, Box 124, 221 00, Lund, Sweden
| | - Cecilia Eriksson Linsmeier
- Neuronano Research Center, Department of Experimental Medical Science, Faculty of Medicine, Lund University, Medicon Village, Building 404 A2, Scheelevägen 2, 223 81, Lund, Sweden
| | - Jens Schouenborg
- Neuronano Research Center, Department of Experimental Medical Science, Faculty of Medicine, Lund University, Medicon Village, Building 404 A2, Scheelevägen 2, 223 81, Lund, Sweden. .,NanoLund, Lund University, Professorsgatan 1, 223 63, Lund, Sweden.
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127
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Liu Y, Wu C, Hou Z, Fu X, Yuan L, Sun S, Zhang H, Yang D, Yao X, Yang J. Pseudoginsenoside-F11 Accelerates Microglial Phagocytosis of Myelin Debris and Attenuates Cerebral Ischemic Injury Through Complement Receptor 3. Neuroscience 2020; 426:33-49. [DOI: 10.1016/j.neuroscience.2019.11.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 11/06/2019] [Accepted: 11/07/2019] [Indexed: 02/08/2023]
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128
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Aghaie CI, Hausknecht KA, Wang R, Dezfuli PH, Haj-Dahmane S, Kane CJM, Sigurdson WJ, Shen RY. Prenatal Ethanol Exposure and Postnatal Environmental Intervention Alter Dopaminergic Neuron and Microglia Morphology in the Ventral Tegmental Area During Adulthood. Alcohol Clin Exp Res 2020; 44:435-444. [PMID: 31872887 DOI: 10.1111/acer.14275] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 12/13/2019] [Indexed: 12/27/2022]
Abstract
BACKGROUND Prenatal ethanol exposure (PE) impairs midbrain dopaminergic (DA) neuron function, which might contribute to various cognitive and behavioral deficits, including attention deficits and increased addiction risk, often observed in individuals with fetal alcohol spectrum disorders. Currently, the underlying mechanisms for PE-induced deficits are unclear. PE could lead to neuroinflammation by activating microglia, which play an important role in synaptic function. In the present study, we investigated PE effects on microglial activation and DA neuron density and morphology in the ventral tegmental area (VTA). Since postnatal environmental enrichment can reduce neuroinflammation and ameliorate several PE-induced behavioral deficits, we examined if a postnatal environmental intervention strategy using neonatal handling and postweaning complex housing could reverse PE effects on VTA DA neurons and microglia. METHODS Pregnant rats received 0 or 6 g/kg/d ethanol by 2 intragastric intubations on gestation days 8 to 20. After birth, rats were reared in the standard laboratory or enriched condition. Male adult rats (8 to 12 weeks old) were used for immunocytochemistry. RESULTS The results showed that PE decreased VTA DA neuron body size in standardly housed rats. Moreover, there was a significant decrease in numbers of VTA microglial branches and junctions in PE rats, suggesting morphological activation of microglia and possible neuroinflammation. The PE effects on microglia were normalized by postnatal environmental intervention, which also decreased the numbers of microglial branches and junctions in control animals, possibly via reduced stress. CONCLUSIONS Our findings show an association between PE-induced morphological activation of microglia and impaired DA neuron morphology in the VTA. Importantly, postnatal environmental intervention rescues possible PE-induced microglial activation. These data support that environmental intervention can be effective in ameliorating cognitive and behavioral deficits associated with VTA DA neuron dysfunctions, such as attention deficits and increased addiction risk.
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Affiliation(s)
- Claudia I Aghaie
- Department of Pathology and Anatomical Sciences, University at Buffalo, Buffalo, New York
| | - Kathryn A Hausknecht
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York
| | - Ruixiang Wang
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York
| | | | - Samir Haj-Dahmane
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York
| | - Cynthia J M Kane
- Department of Neurobiology and Developmental Sciences, College of Medicine, the University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Wade J Sigurdson
- Department of Pathology and Anatomical Sciences, University at Buffalo, Buffalo, New York
| | - Roh-Yu Shen
- Department of Pathology and Anatomical Sciences, University at Buffalo, Buffalo, New York.,Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York
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129
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García-Magro N, Martin YB, Palomino-Antolin A, Egea J, Negredo P, Avendaño C. Multiple Morphometric Assessment of Microglial Cells in Deafferented Spinal Trigeminal Nucleus. Front Neuroanat 2020; 13:103. [PMID: 32038181 PMCID: PMC6987390 DOI: 10.3389/fnana.2019.00103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 12/16/2019] [Indexed: 12/11/2022] Open
Abstract
Microglia (MG) are the first cells to react to the abnormal incoming signals that follow an injury of sensory nerves and play a critical role in the development and maintenance of neuropathic pain, a common sequel of nerve injuries. Here we present population data on cell number, soma size, and length of processes of MG in the caudal division of the spinal trigeminal nucleus (Sp5C) in control mice and at the peak of microgliosis (7 days) following unilateral transection of the infraorbital nerve (IoN). The study is performed combining several bias- and assumption-free imaging and stereological approaches with different immunolabeling procedures, with the objective of tackling some hard problems that often hinder proper execution of MG morphometric studies. Our approach may easily be applied to low-density MG populations, but also works, with limited biases, in territories where MG cell bodies and processes form dense meshworks. In controls, and contralaterally to the deafferented side, MG cell body size and shape and branching pattern matched well the descriptions of “resting” or “surveillant” MG described elsewhere, with only moderate intersubject variability. On the superficial laminae of the deafferented side, however, MG displayed on average larger somata and remarkable diversity in shape. The number of cells and the length of MG processes per mm3 increased 5 and 2.5 times, respectively, indicating a net 50% decrease in the mean length of processes per cell. By using specific immunolabeling and cell sorting of vascular macrophages, we found only a negligible fraction of these cells in Sp5C, with no differences between controls and deafferented animals, suggesting that blood-borne monocytes play at most a very limited role in the microgliosis occurring following sensory nerve deafferentation. In sum, here we present reliable morphometric data on MG in control and deafferented trigeminal nuclei using efficient methods that we propose may equally be applied to any morphometric population analysis of these cells under different physiological or pathological conditions.
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Affiliation(s)
- Nuria García-Magro
- Department of Anatomy, Histology and Neuroscience, Medical School, Autonomous University of Madrid, Madrid, Spain.,Ph.D. Programme in Neuroscience, Doctoral School, Autonomous University of Madrid, Madrid, Spain
| | - Yasmina B Martin
- Department of Anatomy, Faculty of Medicine, Francisco de Vitoria University, Madrid, Spain
| | - Alejandra Palomino-Antolin
- Research Unit, Hospital Universitario Santa Cristina, Instituto de Investigación Sanitaria Hospital Universitario de La Princesa, Madrid, Spain
| | - Javier Egea
- Research Unit, Hospital Universitario Santa Cristina, Instituto de Investigación Sanitaria Hospital Universitario de La Princesa, Madrid, Spain
| | - Pilar Negredo
- Department of Anatomy, Histology and Neuroscience, Medical School, Autonomous University of Madrid, Madrid, Spain
| | - Carlos Avendaño
- Department of Anatomy, Histology and Neuroscience, Medical School, Autonomous University of Madrid, Madrid, Spain
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130
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Kelly R, Joers V, Tansey MG, McKernan DP, Dowd E. Microglial Phenotypes and Their Relationship to the Cannabinoid System: Therapeutic Implications for Parkinson's Disease. Molecules 2020; 25:molecules25030453. [PMID: 31973235 PMCID: PMC7037317 DOI: 10.3390/molecules25030453] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/14/2020] [Accepted: 01/16/2020] [Indexed: 12/11/2022] Open
Abstract
Parkinson’s disease is a neurodegenerative disorder, the motor symptoms of which are associated classically with Lewy body formation and nigrostriatal degeneration. Neuroinflammation has been implicated in the progression of this disease, by which microglia become chronically activated in response to α-synuclein pathology and dying neurons, thereby acquiring dishomeostatic phenotypes that are cytotoxic and can cause further neuronal death. Microglia have a functional endocannabinoid signaling system, expressing the cannabinoid receptors in addition to being capable of synthesizing and degrading endocannabinoids. Alterations in the cannabinoid system—particularly an upregulation in the immunomodulatory CB2 receptor—have been demonstrated to be related to the microglial activation state and hence the microglial phenotype. This paper will review studies that examine the relationship between the cannabinoid system and microglial activation, and how this association could be manipulated for therapeutic benefit in Parkinson’s disease.
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Affiliation(s)
- Rachel Kelly
- Pharmacology & Therapeutics, National University of Ireland, H91 W5P7 Galway, Ireland; (R.K.); (D.P.M.)
| | - Valerie Joers
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL 32611, USA; (V.J.); (M.G.T.)
| | - Malú G. Tansey
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL 32611, USA; (V.J.); (M.G.T.)
- Center for Translation Research in Neurodegenerative Disease, University of Florida College of Medicine, Gainesville, FL 32611, USA
| | - Declan P. McKernan
- Pharmacology & Therapeutics, National University of Ireland, H91 W5P7 Galway, Ireland; (R.K.); (D.P.M.)
| | - Eilís Dowd
- Pharmacology & Therapeutics, National University of Ireland, H91 W5P7 Galway, Ireland; (R.K.); (D.P.M.)
- Correspondence:
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131
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Motataianu A, Barcutean L, Balasa R. Neuroimmunity in amyotrophic lateral sclerosis: focus on microglia. Amyotroph Lateral Scler Frontotemporal Degener 2020; 21:159-166. [PMID: 31903792 DOI: 10.1080/21678421.2019.1708949] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS), an incurable, devastating condition of the central nervous system, is characterized by selective destruction of motoneurons with an important contribution of innate and adaptative immunity. Microglia and immune cells are key players in neuroinflammation and active participants in ALS pathogenesis. Recent experiments in animal models have shown that microglia display both neuroprotective and neurotoxic properties, depending on the stage of disease progression and cytokine secretion. A better knowledge of the interactions between T cells and microglia in the immunopathogenesis of ALS is desirable for the development of ALS therapeutic strategies.
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Affiliation(s)
- Anca Motataianu
- Neurology Department, University of Medicine, Pharmacy, Science and Technology "George Emil Palade", Targu Mures, Romania
| | - Laura Barcutean
- Neurology Department, University of Medicine, Pharmacy, Science and Technology "George Emil Palade", Targu Mures, Romania
| | - Rodica Balasa
- Neurology Department, University of Medicine, Pharmacy, Science and Technology "George Emil Palade", Targu Mures, Romania
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132
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Sugama S, Takenouchi T, Hashimoto M, Ohata H, Takenaka Y, Kakinuma Y. Stress-induced microglial activation occurs through β-adrenergic receptor: noradrenaline as a key neurotransmitter in microglial activation. J Neuroinflammation 2019; 16:266. [PMID: 31847911 PMCID: PMC6916186 DOI: 10.1186/s12974-019-1632-z] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Accepted: 11/06/2019] [Indexed: 02/06/2023] Open
Abstract
Background The involvement of microglia in neuroinflammatory responses has been extensively demonstrated. Recent animal studies have shown that exposure to either acute or chronic stress induces robust microglial activation in the brain. In the present study, we investigated the underlying mechanism of brain microglial activation by acute stress. Methods We first looked at the spatial distribution of the noradrenaline (NA)-synthesizing enzyme, DBH (dopamine β-hydroxylase), in comparison with NA receptors—β1, β2, and β3 adrenergic receptors (β1-AR, β2-AR, and β3-AR)—after which we examined the effects of the β-blocker propranolol and α-blockers prazosin and yohimbine on stress-induced microglial activation. Finally, we compared stress-induced microglial activation between wild-type (WT) mice and double-knockout (DKO) mice lacking β1-AR and β2-AR. Results The results demonstrated that (1) microglial activation occurred in most studied brain regions, including the hippocampus (HC), thalamus (TM), and hypothalamus (HT); (2) within these three brain regions, the NA-synthesizing enzyme DBH was densely stained in the neuronal fibers; (3) β1-AR and β2-AR, but not β3-AR, are detected in the whole brain, and β1-AR and β2-AR are co-localized with microglial cells, as observed by laser scanning microscopy; (4) β-blocker treatment inhibited microglial activation in terms of morphology and count through the whole brain; α-blockers did not show such effect; (5) unlike WT mice, DKO mice exhibited substantial inhibition of stress-induced microglial activation in the brain. Conclusions We demonstrate that neurons/microglia may interact with NA via β1-AR and β2-AR.
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Affiliation(s)
- Shuei Sugama
- Department of Physiology, Nippon Medical School, 1-1-5 Sendagi Bunkyo-ku, Tokyo, 113-8602, Japan.
| | - Takato Takenouchi
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Ohwashi, Tsukuba, Ibaraki, 305-8634, Japan
| | - Makoto Hashimoto
- Division of Sensory and Motor Systems, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-0057, Japan
| | - Hisayuki Ohata
- Department of Physiology, Nippon Medical School, 1-1-5 Sendagi Bunkyo-ku, Tokyo, 113-8602, Japan
| | - Yasuhiro Takenaka
- Department of Physiology, Nippon Medical School, 1-1-5 Sendagi Bunkyo-ku, Tokyo, 113-8602, Japan
| | - Yoshihiko Kakinuma
- Department of Physiology, Nippon Medical School, 1-1-5 Sendagi Bunkyo-ku, Tokyo, 113-8602, Japan
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133
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Frost GR, Jonas LA, Li YM. Friend, Foe or Both? Immune Activity in Alzheimer's Disease. Front Aging Neurosci 2019; 11:337. [PMID: 31920620 PMCID: PMC6916654 DOI: 10.3389/fnagi.2019.00337] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 11/21/2019] [Indexed: 12/18/2022] Open
Abstract
Alzheimer's disease (AD) is marked by the presence of amyloid beta (Aβ) plaques, neurofibrillary tangles (NFT), neuronal death and synaptic loss, and inflammation in the brain. AD research has, in large part, been dedicated to the understanding of Aβ and NFT deposition as well as to the pharmacological reduction of these hallmarks. However, recent GWAS data indicates neuroinflammation plays a critical role in AD development, thereby redirecting research efforts toward unveiling the complexities of AD-associated neuroinflammation. It is clear that the innate immune system is intimately associated with AD progression, however, the specific roles of glia and neuroinflammation in AD pathology remain to be described. Moreover, inflammatory processes have largely been painted as detrimental to AD pathology, when in fact, many immune mechanisms such as phagocytosis aid in the reduction of AD pathologies. In this review, we aim to outline the delicate balance between the beneficial and detrimental aspects of immune activation in AD as a more thorough understanding of these processes is critical to development of effective therapeutics for AD.
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Affiliation(s)
- Georgia R. Frost
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, Manhattan, NY, United States
| | - Lauren A. Jonas
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, Manhattan, NY, United States
- Pharmacology Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, Ithaca, NY, United States
| | - Yue-Ming Li
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, Manhattan, NY, United States
- Pharmacology Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, Ithaca, NY, United States
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134
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Franco-Bocanegra DK, George B, Lau LC, Holmes C, Nicoll JAR, Boche D. Microglial motility in Alzheimer's disease and after Aβ42 immunotherapy: a human post-mortem study. Acta Neuropathol Commun 2019; 7:174. [PMID: 31703599 PMCID: PMC6842157 DOI: 10.1186/s40478-019-0828-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 10/13/2019] [Indexed: 02/04/2023] Open
Abstract
Microglial function is highly dependent on cell motility, with baseline motility required for homeostatic surveillance activity and directed motility to migrate towards a source of injury. Experimental evidence suggests impaired microglial motility in Alzheimer’s disease (AD) and therefore we have investigated whether the expression of proteins associated with motility is altered in AD and affected by the Aβ immunotherapy using post-mortem brain tissue of 32 controls, 44 AD cases, and 16 AD cases from our unique group of patients immunised against Aβ42 (iAD). Sections of brain were immunolabelled and quantified for (i) the motility-related microglial proteins Iba1, cofilin 1 (CFL1), coronin-1a (CORO1A) and P2RY12, and (ii) pan-Aβ, Aβ42 and phosphorylated tau (ptau). The neuroinflammatory environment was characterised using Meso Scale Discovery multiplex assays. The expression of all four motility-related proteins was unmodified in AD compared with controls, whereas Iba1 and P2RY12, the homeostatic markers, were increased in the iAD group compared with AD. Iba1 and P2RY12 showed significant positive correlations with Aβ in controls but not in the AD or iAD groups. Pro- and anti-inflammatory proteins were increased in AD, whereas immunotherapy appears to result in a slightly less pro-inflammatory environment. Our findings suggest that as Aβ appears during the ageing process, the homeostatic Iba1 and P2RY12 –positive microglia respond to Aβ, but this response is absent in AD. Aβ-immunisation promoted increased Iba1 and P2RY12 expression, likely reflecting increased baseline microglial motility but without restoring the profile observed in controls.
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135
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Kim JD, Yoon NA, Jin S, Diano S. Microglial UCP2 Mediates Inflammation and Obesity Induced by High-Fat Feeding. Cell Metab 2019; 30:952-962.e5. [PMID: 31495690 PMCID: PMC7251564 DOI: 10.1016/j.cmet.2019.08.010] [Citation(s) in RCA: 131] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 05/01/2019] [Accepted: 08/09/2019] [Indexed: 11/19/2022]
Abstract
Microglia play a crucial role in immune responses, including inflammation. Diet-induced obesity (DIO) triggers microglia activation and hypothalamic inflammation as early as 3 days after high-fat diet (HFD) exposure, before changes in body weight occur. The intracellular mechanism(s) responsible for HFD-induced microglia activation is ill defined. Here, we show that in vivo, HFD induced a rapid and transient increase in uncoupling protein 2 (Ucp2) mRNA expression together with changes in mitochondrial dynamics. Selective microglial deletion of Ucp2 prevented changes in mitochondrial dynamics and function, microglia activation, and hypothalamic inflammation. In association with these, male and female mice were protected from HFD-induced obesity, showing decreased feeding and increased energy expenditure that were associated with changes in the synaptic input organization and activation of the anorexigenic hypothalamic POMC neurons and astrogliosis. Together, our data point to a fuel-availability-driven mitochondrial mechanism as a major player of microglia activation in the central regulation of DIO.
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Affiliation(s)
- Jung Dae Kim
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Nal Ae Yoon
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Sungho Jin
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Sabrina Diano
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Neuroscience, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples 80131, Italy.
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136
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Frye MD, Ryan AF, Kurabi A. Inflammation associated with noise-induced hearing loss. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 146:4020. [PMID: 31795714 PMCID: PMC7480080 DOI: 10.1121/1.5132545] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 06/17/2019] [Accepted: 06/20/2019] [Indexed: 05/22/2023]
Abstract
Inflammation is a complex biological response to harmful stimuli including infection, tissue damage, and toxins. Thus, it is not surprising that cochlear damage by noise includes an inflammatory component. One mechanism by which inflammation is generated by tissue damage is the activation of damage-associated molecular patterns (DAMPs). Many of the cellular receptors for DAMPS, including Toll-like receptors, NOD-like receptors, and DNA receptors, are also receptors for pathogens, and function in the innate immune system. DAMP receptors are known to be expressed by cochlear cells, and binding of molecules released by damaged cells to these receptors result in the activation of cell stress pathways. This leads to the generation of pro-inflammatory cytokines and chemokines that recruit pro-inflammatory leukocytes. Extensive evidence indicates pro-inflammatory cytokines including TNF alpha and interleukin 1 beta, and chemokines including CCL2, are induced in the cochlea after noise exposure. The recruitment of macrophages into the cochlea has also been demonstrated. These provide substrates for noise damage to be enhanced by inflammation. Evidence is provided by the effectiveness of anti-inflammatory drugs in ameliorating noise-induced hearing loss. Involvement of inflammation provides a wide variety of additional anti-inflammatory and pro-resolution agents as potential pharmacological interventions in noise-induced hearing loss.
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Affiliation(s)
- Mitchell D Frye
- Callier Center for Communication Disorders, School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, Texas 75080, USA
| | - Allen F Ryan
- Department of Surgery/Otolaryngology, University of California San Diego, School of Medicine, and Veterans Administration Medical Center, La Jolla, California 92093, USA
| | - Arwa Kurabi
- Department of Surgery/Otolaryngology, University of California San Diego, School of Medicine, and Veterans Administration Medical Center, La Jolla, California 92093, USA
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137
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Fernández-Arjona MDM, Grondona JM, Fernández-Llebrez P, López-Ávalos MD. Microglial Morphometric Parameters Correlate With the Expression Level of IL-1β, and Allow Identifying Different Activated Morphotypes. Front Cell Neurosci 2019; 13:472. [PMID: 31708746 PMCID: PMC6824358 DOI: 10.3389/fncel.2019.00472] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 10/02/2019] [Indexed: 12/22/2022] Open
Abstract
Microglia are the resident macrophages in the brain. Traditionally, two forms of microglia have been described: one considered as a resting/surveillant state in which cells have a highly branched morphology, and another considered as an activated state in which they acquire a de-ramified or amoeboid form. However, many studies describe intermediate microglial morphologies which emerge during pathological processes. Since microglial form and function are closely related, it is of interest to correlate microglial morphology with the extent of its activation. To address this issue, we used a rat model of neuroinflammation consisting in a single injection of the enzyme neuraminidase (NA) within the lateral ventricle. Sections from NA-injected animals were co-immunolabeled with the microglial marker IBA1 and the cytokine IL-1β, which highlight features of the cell’s shape and inflammatory activation, respectively. Activated (IL-1β positive) microglial cells were sampled from the dorsal hypothalamus nearby the third ventricle. Images of single microglial cells were processed in two different ways to obtain (1) an accurate measure of the level of expression of IL-1β (indicating the degree of activation), and (2) a set of 15 morphological parameters to quantitatively and objectively describe the cell’s shape. A simple regression analysis revealed a dependence of most of the morphometric parameters on IL-1β expression, demonstrating that the morphology of microglial cells changes progressively with the degree of activation. Moreover, a hierarchical cluster analysis pointed out four different morphotypes of activated microglia, which are characterized not only by morphological parameters values, but also by specific IL-1β expression levels. Thus, these results demonstrate in an objective manner that the activation of microglial cells is a gradual process, and correlates with their morphological change. Even so, it is still possible to categorize activated cells according to their morphometric parameters, each category presenting a different activation degree. The physiological relevance of those activated morphotypes is an issue worth to be assessed in the future.
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Affiliation(s)
| | - Jesús M Grondona
- Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
| | - Pedro Fernández-Llebrez
- Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
| | - María D López-Ávalos
- Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
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138
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Noda M, Hatano M, Hattori T, Takarada-Iemata M, Shinozaki T, Sugimoto H, Ito M, Yoshizaki T, Hori O. Microglial activation in the cochlear nucleus after early hearing loss in rats. Auris Nasus Larynx 2019; 46:716-723. [DOI: 10.1016/j.anl.2019.02.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/18/2019] [Accepted: 02/13/2019] [Indexed: 01/22/2023]
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139
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Ferguson M, Sharma D, Ross D, Zhao F. A Critical Review of Microelectrode Arrays and Strategies for Improving Neural Interfaces. Adv Healthc Mater 2019; 8:e1900558. [PMID: 31464094 PMCID: PMC6786932 DOI: 10.1002/adhm.201900558] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/25/2019] [Indexed: 12/19/2022]
Abstract
Though neural interface systems (NISs) can provide a potential solution for mitigating the effects of limb loss and central nervous system damage, the microelectrode array (MEA) component of NISs remains a significant limiting factor to their widespread clinical applications. Several strategies can be applied to MEA designs to increase their biocompatibility. Herein, an overview of NISs and their applications is provided, along with a detailed discussion of strategies for alleviating the foreign body response (FBR) and abnormalities seen at the interface of MEAs and the brain tissue following MEA implantation. Various surface modifications, including natural/synthetic surface coatings, hydrogels, and topography alterations, have shown to be highly successful in improving neural cell adhesion, reducing gliosis, and increasing MEA longevity. Different MEA surface geometries, such as those seen in the Utah and Michigan arrays, can help alleviate the resultant FBR by reducing insertion damage, while providing new avenues for improving MEA recording performance and resolution. Increasing overall flexibility of MEAs as well as reducing their stiffness is also shown to reduce MEA induced micromotion along with FBR severity. By combining multiple different properties into a single MEA, the severity and duration of an FBR postimplantation can be reduced substantially.
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Affiliation(s)
- Morgan Ferguson
- Department of Biomedical Engineering, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931
| | - Dhavan Sharma
- Department of Biomedical Engineering, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931
| | - David Ross
- Department of Biomedical Engineering, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931
| | - Feng Zhao
- Department of Biomedical Engineering, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931
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140
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Gao Y, Liu EJ, Wang WJ, Wang YL, Li XG, Wang X, Li SH, Zhang SJ, Li MZ, Zhou QZ, Long XB, Zhang HQ, Wang JZ. Microglia CREB-Phosphorylation Mediates Amyloid-β-Induced Neuronal Toxicity. J Alzheimers Dis 2019; 66:333-345. [PMID: 30282353 DOI: 10.3233/jad-180286] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Extracellular accumulation of amyloid-β (Aβ) forming senile plaques is one of the hallmark pathologies in Alzheimer's disease (AD), while the mechanisms underlying the neuronal toxic effect of Aβ are not fully understood. Here, we found that intracerebroventricular infusion of the aged Aβ42 in mice only induces memory deficit at 24 h but not at 7 days. Interestingly, a remarkably increased CREB (cAMP response element-binding protein) Ser133-phosphorylation (pS133-CREB) with microglial activation was detected at 24 h but not at 7 days after Aβ infusion. Aβ treatment for 24 h increased pS133-CREB level in microglia of the hippocampal non-granular cell layers with remarkably decreased pS133-CREB immunoreactivity in neurons of the hippocampal granular cell layers, including CA1, CA3, and DG subsets. Inhibition of microglia activation by minocycline or CREB phosphorylation by H89, an inhibitor of protein kinase A (PKA), abolished Aβ-induced microglia CREB hyperphosphorylation with restoration of neuronal function and attenuation of inflammatory response, i.e., reduced levels of interleukin-6 (IL6) and pCREB binding of matrix metalloproteinase-9 (MMP9) DNA. Finally, treatment of the primary hippocampal neurons with Aβ-potentiated microglia media decreased neuronal GluN1 and GluA2 levels, while simultaneous inhibition of PKA restored the levels. These novel findings reveal that intracerebroventricular infusion of Aβ only induces transient memory deficit in mice and the molecular mechanisms involve a stimulated microglial CREB phosphorylation.
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Affiliation(s)
- Yuan Gao
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - En-Jie Liu
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wei-Jin Wang
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ya-Li Wang
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao-Guang Li
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xin Wang
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shi-Hong Li
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shu-Juan Zhang
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Meng-Zhu Li
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qiu-Zhi Zhou
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao-Bing Long
- Neurosurgery Department, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Hospital, Tongji Medical College, Wuhan, China
| | - Hua-Qiu Zhang
- Neurosurgery Department, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Hospital, Tongji Medical College, Wuhan, China
| | - Jian-Zhi Wang
- Pathophysiology Department, School of Basic Medicine, Key Laboratory of Ministry of Education of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
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141
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Lauro C, Chece G, Monaco L, Antonangeli F, Peruzzi G, Rinaldo S, Paone A, Cutruzzolà F, Limatola C. Fractalkine Modulates Microglia Metabolism in Brain Ischemia. Front Cell Neurosci 2019; 13:414. [PMID: 31607865 PMCID: PMC6755341 DOI: 10.3389/fncel.2019.00414] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 08/27/2019] [Indexed: 01/17/2023] Open
Abstract
In the CNS, the chemokine CX3CL1 (fractalkine) is expressed on neurons while its specific receptor CX3CR1 is expressed on microglia and macrophages. Microglia play an important role in health and disease through CX3CL1/CX3CR1 signaling, and in many neurodegenerative disorders, microglia dysregulation has been associated with neuro-inflammation. We have previously shown that CX3CL1 has neuroprotective effects against cerebral ischemia injury. Here, we investigated the involvement of CX3CL1 in the modulation of microglia phenotype and the underlying neuroprotective effect on ischemia injury. The expression profiles of anti- and pro-inflammatory genes showed that CX3CL1 markedly inhibited microglial activation both in vitro and in vivo after permanent middle cerebral artery occlusion (pMCAO), accompanied by an increase in the expression of anti-inflammatory genes. Moreover, CX3CL1 induces a metabolic switch in microglial cells with an increase in the expression of genes related to the oxidative pathway and a reduction in those related to the glycolytic pathway, which is the metabolic state associated to the pro-inflammatory phenotype for energy production. The data reported in this paper suggest that CX3CL1 protects against cerebral ischemia modulating the activation state of microglia and its metabolism in order to restrain inflammation and organize a neuroprotective response against the ischemic insult.
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Affiliation(s)
- Clotilde Lauro
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Giuseppina Chece
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Lucia Monaco
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Fabrizio Antonangeli
- Department of Molecular Medicine, Laboratory Affiliated to Istituto Pasteur Italia - Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Giovanna Peruzzi
- Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Rome, Italy
| | - Serena Rinaldo
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy
| | - Alessio Paone
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy
| | - Francesca Cutruzzolà
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy
| | - Cristina Limatola
- Department of Physiology and Pharmacology, Laboratory Affiliated to Istituto Pasteur Italia - Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy.,IRCCS NeuroMed, Pozzilli, Italy
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142
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Parra I, Martínez I, Ramírez-García G, Tizabi Y, Mendieta L. Differential Effects of LPS and 6-OHDA on Microglia's Morphology in Rats: Implications for Inflammatory Model of Parkinson's Disease. Neurotox Res 2019; 37:1-11. [PMID: 31478124 DOI: 10.1007/s12640-019-00104-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 08/05/2019] [Accepted: 08/22/2019] [Indexed: 01/27/2023]
Abstract
Parkinson's disease (PD) is an idiopathic and progressive neurodegenerative disease characterized by the loss of ~ 80% of dopaminergic neurons in substantia nigra pars compacta (SNpc). Because activation of the innate cellular immune response, mediated by microglia, has been linked to the neurodegeneration in PD, in the present study, we evaluated the effects of lipopolysaccharide (LPS) and 6-hydroxydopamine (6-OHDA) on microglia's morphology, reflective of their activity, as well as tyrosine hydroxylase (TH)-positive neurons in SNpc and motor behavior. Adult male Wistar rats were stereotactically injected with LPS or 6-OHDA into the left dorsolateral striatum. Control groups received appropriate vehicle. The morphological changes of microglial cells and neurotoxic effects were examined at 1, 7, and 14 post-injection days. Both LPS and 6-OHDA caused activation and morphological changes in microglial cells as well as loss of dopaminergic neurons in SNpc. These effects were maximal at 14 days post-injection where motor impairments were also evident. However, our findings indicate that 6-OHDA causes a low degree of microglia activation compared to LPS. Hence, it may be concluded that LPS model of PD might be a better representation of inflammatory involvement in this devastating disease.
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Affiliation(s)
- Irving Parra
- Laboratorio de Neuroquímica, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio CU, Col. San Manuel, 72570, Puebla, Mexico
| | - Isabel Martínez
- Laboratorio de Neuroquímica, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio CU, Col. San Manuel, 72570, Puebla, Mexico
| | - Gabriel Ramírez-García
- Unidad Periférica de Neurociencias, Facultad de Medicina, Universidad Nacional Autónoma de México, Instituto Nacional de Neurología y Neurocirugía "Manuel Velasco Suárez", Ciudad de Mexico, Mexico
| | - Yousef Tizabi
- Department of Pharmacology, Howard University College of Medicine, Washington, DC, USA
| | - Liliana Mendieta
- Laboratorio de Neuroquímica, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio CU, Col. San Manuel, 72570, Puebla, Mexico.
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143
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Zhang Z, Hou H, Yu S, Zhou C, Zhang X, Li N, Zhang S, Song K, Lu Y, Liu D, Lu H, Xu H. Inflammation-induced mammalian target of rapamycin signaling is essential for retina regeneration. Glia 2019; 68:111-127. [PMID: 31444939 DOI: 10.1002/glia.23707] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 08/05/2019] [Accepted: 08/07/2019] [Indexed: 12/18/2022]
Abstract
Upon retina injury, Müller glia in the zebrafish retina respond by generating multipotent progenitors to repair the retina. However, the complete mechanisms underlying retina regeneration remain elusive. Here we report inflammation-induced mammalian target of rapamycin (mTOR) signaling in the Müller glia is essential for retina regeneration in adult zebrafish. We show after a stab injury, mTOR is rapidly activated in Müller glia and later Müller glia-derived progenitor cells (MGPCs). Importantly, mTOR is required for Müller glia dedifferentiation, as well as the proliferation of Müller glia and MGPCs. Interestingly, transient mTOR inhibition by rapamycin only reversibly suppresses MGPC proliferation, while its longer suppression by knocking down Raptor significantly inhibits the regeneration of retinal neurons. We further show mTOR promotes retina regeneration by regulating the mRNA expression of key reprogramming factors ascl1a and lin-28a, cell cycle-related genes and critical cytokines. Surprisingly, we identify microglia/macrophage-mediated inflammation as an important upstream regulator of mTOR in the Müller glia and it promotes retina regeneration through mTOR. Our study not only demonstrates the important functions of mTOR but also reveals an interesting link between inflammation and the mTOR signaling during retina regeneration.
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Affiliation(s)
- Zhiqiang Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Jiangsu Province, China
| | - Haitao Hou
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Jiangsu Province, China
| | - Shuguang Yu
- State Key Laboratory of Neuroscience, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Cuiping Zhou
- Department of Ophthalmology, Eye Institute, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Xiaoli Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Jiangsu Province, China
| | - Na Li
- Department of Ophthalmology, Eye Institute, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Shuqiang Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Jiangsu Province, China
| | - Kaida Song
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Jiangsu Province, China
| | - Ying Lu
- Department of Ophthalmology, Eye Institute, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Dong Liu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Jiangsu Province, China
| | - Hong Lu
- Department of Ophthalmology, Eye Institute, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Hui Xu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Jiangsu Province, China
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144
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Du H, Chen X, Zhang L, Liu Y, Zhan C, Chen J, Wang H, Yu Z, Liang C. Experimental Autoimmune Prostatitis Induces Learning-Memory Impairment and Structural Neuroplastic Changes in Mice. Cell Mol Neurobiol 2019; 40:99-111. [DOI: 10.1007/s10571-019-00723-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 08/07/2019] [Indexed: 01/28/2023]
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145
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Shtaya A, Bridges LR, Esiri MM, Lam‐Wong J, Nicoll JAR, Boche D, Hainsworth AH. Rapid neuroinflammatory changes in human acute intracerebral hemorrhage. Ann Clin Transl Neurol 2019; 6:1465-1479. [PMID: 31402627 PMCID: PMC6689697 DOI: 10.1002/acn3.50842] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/19/2019] [Accepted: 06/25/2019] [Indexed: 01/06/2023] Open
Abstract
OBJECTIVE Spontaneous intracerebral hemorrhage (ICH) is the commonest form of hemorrhagic stroke and is associated with a poor prognosis. Neurosurgical removal of intracerebral hematoma has limited benefit and no pharmacotherapies are available. In acute ICH, primary tissue damage is followed by secondary pathology, where the cellular and neuroinflammatory changes are poorly understood. METHODS We studied histological changes in postmortem tissue from a cohort of spontaneous supra-tentorial primary ICH cases (n = 27) with survival of 1-12 days, compared to a matched control group (n = 16) examined in corresponding regions. Hematoxylin-eosin and microglial (Iba1) immunolabelled sections were assessed at 0-2, 3-5, and 7-12 days post-ICH. RESULTS Peri-hematoma, the observed ICH-related changes include edema, tissue neutrophils and macrophages from day 1. Ischemic neurons and swollen endothelial cells were common at day 1 and universal after day 5, as were intramural erythrocytes within small vessel walls. Activated microglia were evident at day 1 post-ICH. There was a significant increase in Iba1 positive area fraction at 0-2 (threefold), 3-5 (fourfold), and 7-12 days post ICH (ninefold) relative to controls. Giant microglia were detected peri-hematoma from day 5 and consistently 7-12 days post-ICH. INTERPRETATION Our data indicate that neuroinflammatory processes commence from day 1 post-ICH with changing microglial size and morphology following ICH and up to day 12. From day 5 some microglia exhibit a novel multiply nucleated morphology, which may be related to changing phagocytic function. Understanding the time course of neuroinflammatory changes, post-ICH may reveal novel targets for therapy and brain restoration.
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Affiliation(s)
- Anan Shtaya
- Neuroscience Research Centre, Molecular and Clinical Sciences Research InstituteSt. George’s, University of LondonLondonUK
| | - Leslie R. Bridges
- Department of Cellular PathologySt George's University Hospitals NHS Foundation TrustLondonUK
| | - Margaret M. Esiri
- Nuffield Department of Clinical NeurosciencesOxford UniversityOxfordUK
| | - Joanne Lam‐Wong
- Department of Cellular PathologySt George's University Hospitals NHS Foundation TrustLondonUK
| | - James A. R. Nicoll
- Clinical Neurosciences, Clinical & Experimental SciencesUniversity of SouthamptonSouthamptonUK
| | - Delphine Boche
- Clinical Neurosciences, Clinical & Experimental SciencesUniversity of SouthamptonSouthamptonUK
| | - Atticus H. Hainsworth
- Neuroscience Research Centre, Molecular and Clinical Sciences Research InstituteSt. George’s, University of LondonLondonUK
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146
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Elevated TREM2 Gene Dosage Reprograms Microglia Responsivity and Ameliorates Pathological Phenotypes in Alzheimer's Disease Models. Neuron 2019. [PMID: 29518357 DOI: 10.1016/j.neuron.2018.02.002] [Citation(s) in RCA: 226] [Impact Index Per Article: 45.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Variants of TREM2 are associated with Alzheimer's disease (AD). To study whether increasing TREM2 gene dosage could modify the disease pathogenesis, we developed BAC transgenic mice expressing human TREM2 (BAC-TREM2) in microglia. We found that elevated TREM2 expression reduced amyloid burden in the 5xFAD mouse model. Transcriptomic profiling demonstrated that increasing TREM2 levels conferred a rescuing effect, which includes dampening the expression of multiple disease-associated microglial genes and augmenting downregulated neuronal genes. Interestingly, 5xFAD/BAC-TREM2 mice showed further upregulation of several reactive microglial genes linked to phagocytosis and negative regulation of immune cell activation. Moreover, these mice showed enhanced process ramification and phagocytic marker expression in plaque-associated microglia and reduced neuritic dystrophy. Finally, elevated TREM2 gene dosage led to improved memory performance in AD models. In summary, our study shows that a genomic transgene-driven increase in TREM2 expression reprograms microglia responsivity and ameliorates neuropathological and behavioral deficits in AD mouse models.
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147
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Camacho-Hernández NP, Lorea-Hernández JJ, Peña-Ortega F. Microglial modulators reduce respiratory rhythm long-term facilitation in vitro. Respir Physiol Neurobiol 2019; 265:9-18. [DOI: 10.1016/j.resp.2018.07.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 06/08/2018] [Accepted: 07/30/2018] [Indexed: 12/28/2022]
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148
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Juliano J, Gil O, Hawkins-Daarud A, Noticewala S, Rockne RC, Gallaher J, Massey SC, Sims PA, Anderson ARA, Swanson KR, Canoll P. Comparative dynamics of microglial and glioma cell motility at the infiltrative margin of brain tumours. J R Soc Interface 2019; 15:rsif.2017.0582. [PMID: 29445035 DOI: 10.1098/rsif.2017.0582] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 01/22/2018] [Indexed: 01/03/2023] Open
Abstract
Microglia are a major cellular component of gliomas, and abundant in the centre of the tumour and at the infiltrative margins. While glioma is a notoriously infiltrative disease, the dynamics of microglia and glioma migratory patterns have not been well characterized. To investigate the migratory behaviour of microglia and glioma cells at the infiltrative edge, we performed two-colour time-lapse fluorescence microscopy of brain slices generated from a platelet-derived growth factor-B (PDGFB)-driven rat model of glioma, in which glioma cells and microglia were each labelled with one of two different fluorescent markers. We used mathematical techniques to analyse glioma cells and microglia motility with both single cell tracking and particle image velocimetry (PIV). Our results show microglia motility is strongly correlated with the presence of glioma, while the correlation of the speeds of glioma cells and microglia was variable and weak. Additionally, we showed that microglia and glioma cells exhibit different types of diffusive migratory behaviour. Microglia movement fit a simple random walk, while glioma cell movement fits a super diffusion pattern. These results show that glioma cells stimulate microglia motility at the infiltrative margins, creating a correlation between the spatial distribution of glioma cells and the pattern of microglia motility.
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Affiliation(s)
- Joseph Juliano
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Orlando Gil
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
| | | | - Sonal Noticewala
- University of California San Diego School of Medicine, La Jolla, CA, USA
| | - Russell C Rockne
- Division of Mathematical Oncology, City of Hope National Medical Center, Duarte, CA, USA
| | - Jill Gallaher
- Integrated Mathematical Oncology, H Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | | | - Peter A Sims
- Department of Systems Biology, Columbia University Medical Center, New York, NY, USA
| | - Alexander R A Anderson
- Integrated Mathematical Oncology, H Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | | | - Peter Canoll
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
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149
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Intravital 2-photon imaging reveals distinct morphology and infiltrative properties of glioblastoma-associated macrophages. Proc Natl Acad Sci U S A 2019; 116:14254-14259. [PMID: 31235603 DOI: 10.1073/pnas.1902366116] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Characterized by a dismal survival rate and limited response to therapy, glioblastoma (GBM) remains one of the most aggressive human malignancies. Recent studies of the role of tumor-associated macrophages (TAMs) in the progression of GBMs have demonstrated that TAMs are significant contributors to tumor growth, invasion, and therapeutic resistance. TAMs, which include brain-resident microglia and circulating bone marrow derived-monocytes (BMDMs), are typically grouped together in histopathological and molecular analyses due to the lack of reliable markers of distinction. To develop more effective therapies aimed at specific TAM populations, we must first understand how these cells differ both morphologically and behaviorally. Furthermore, we must develop a deeper understanding of the mechanisms encouraging their infiltration and how these mechanisms can be therapeutically exploited. In this study, we combined immunocompetent lineage tracing mouse models of GBM with high-resolution open-skull 2-photon microscopy to investigate the phenotypical and functional characteristics of TAMs. We demonstrate that TAMs are composed of 2 morphologically distinct cell types that have differential migratory propensities. We show that BMDMs are smaller, minimally branched cells that are highly migratory compared with microglia, which are larger, highly branched stationary cells. In addition, 2 populations of monocytic macrophages were observed that differed in terms of CX3CR1 expression and migratory capacity. Finally, we demonstrate the efficacy of anti-vascular endothelial growth factor A blockade for prohibiting TAM infiltration, especially against BMDMs. Taken together, our data clearly define characteristics of individual TAM populations and suggest that combination therapy with antivascular and antichemotaxis therapy may be an attractive option for treating these tumors.
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150
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Microglia-neuron crosstalk: Signaling mechanism and control of synaptic transmission. Semin Cell Dev Biol 2019; 94:138-151. [PMID: 31112798 DOI: 10.1016/j.semcdb.2019.05.017] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/17/2019] [Accepted: 05/16/2019] [Indexed: 12/13/2022]
Abstract
The continuous crosstalk between microglia and neurons is required for microglia housekeeping functions and contributes to brain homeostasis. Through these exchanges, microglia take part in crucial brain functions, including development and plasticity. The alteration of neuron-microglia communication contributes to brain disease states with consequences, ranging from synaptic function to neuronal survival. This review focuses on the signaling pathways responsible for neuron-microglia crosstalk, highlighting their physiological roles and their alteration or specific involvement in disease. In particular, we discuss studies, establishing how these signaling allow microglial cells to control relevant physiological functions during brain development, including synaptic formation and circuit refinement. In addition, we highlight how microglia and neurons interact functionally to regulate highly dynamical synaptic functions. Microglia are able to release several signaling molecules involved in the regulation of synaptic activity and plasticity. On the other side, molecules of neuronal origin control microglial processes motility in an activity-dependent manner. Indeed, the continuous crosstalk between microglia and neurons is required for the sensing and housekeeping functions of microglia and contributes to the maintenance of brain homeostasis and, particularly, to the sculpting of neuronal connections during development. These interactions lay on the delicate edge between physiological processes and homeostasis alteration in pathology and are themselves altered during neuroinflammation. The full description of these processes could be fundamental for understanding brain functioning in health and disease.
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