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Schiel V, Bhattacharya R, Gupta A, Eftekharian K, Xia A, Santa Maria PL. Targeting the NLRP3 inflammasome in cochlear macrophages protects against hearing loss in chronic suppurative otitis media. J Neuroinflammation 2024; 21:223. [PMID: 39277762 PMCID: PMC11402200 DOI: 10.1186/s12974-024-03212-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Accepted: 08/09/2024] [Indexed: 09/17/2024] Open
Abstract
The activation of the NLRP3 inflammasome has been linked to several inflammatory and autoinflammatory diseases. Despite cases of potential hearing improvement in immune-mediated diseases, direct evidence of the efficacy of targeting this mechanism in the inner ear is still lacking. Previously, we discovered that macrophages are associated with Sensorineural Hearing loss (SNHL) in Chronic Suppurative Otitis Media (CSOM), the leading cause of this permanent hearing loss in the developing world and incurring costs of $4 to $11 billion dollars in the United States. However, the underlying mechanism remained unknown. Here, we investigate how macrophages drive permanent hearing loss in CSOM. We first confirmed the occurrence of NLRP3 inflammasome activation in cochlear macrophages in CSOM. We then revealed that Outer Hair Cells (OHCs) were protected in CSOM by macrophage depletion and subsequently confirmed the same protection in the NLRP3 knockout condition. Furthermore, we showed that therapeutic inhibition of NLRP3 inflammasome activation and downstream inhibition of IL-1β protects OHCs in CSOM. Collectively, our data demonstrates that the main driver for hearing loss in CSOM is NLRP3 inflammasome activation in cochlear macrophages and this is therapeutically targetable, leading the way for the development of interventions to prevent the leading cause of permanent hearing loss and a costly disease in the developed world.
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Affiliation(s)
- Viktoria Schiel
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Stanford University, Palo Alto, CA, 94305, USA
| | - Ritwija Bhattacharya
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Stanford University, Palo Alto, CA, 94305, USA
| | - Ankur Gupta
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Stanford University, Palo Alto, CA, 94305, USA
| | - Kourosh Eftekharian
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Stanford University, Palo Alto, CA, 94305, USA
| | - Anping Xia
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Stanford University, Palo Alto, CA, 94305, USA.
| | - Peter L Santa Maria
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Stanford University, Palo Alto, CA, 94305, USA.
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Lee SH, Shin HS, So YH, Lee DH, Kim JY, Lee EH, Jung EM. Effects of maternal nonylphenol exposure on the proliferation of glial cells in the brain of male offspring mice. Anim Cells Syst (Seoul) 2024; 28:439-452. [PMID: 39280932 PMCID: PMC11395876 DOI: 10.1080/19768354.2024.2401389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2024] [Revised: 08/06/2024] [Accepted: 08/09/2024] [Indexed: 09/18/2024] Open
Abstract
Glial cells play a significant role in maintaining brain homeostasis and normal brain development, and their functions can be impaired by exposure to endocrine disruptors. 4-n-Nonylphenol (NP), a representative endocrine disruptor, is widely used in personal care products and industrial materials. NP accumulates in various organs, including the brain, of living organisms and adversely influences brain health. However, studies on the effects of NP on glial cells are limited. This study aims to investigate the effects of NP on glial cells using primary mixed glial cells and offspring mice exposed to NP during gestation and lactation. In vitro experiments revealed that NP exposure stimulated the astrocytes and microglia proliferation but not oligodendrocytes. NP exposure activated microglia and reduced myelin protein expression in oligodendrocytes. Moreover, maternal NP exposure increased the numbers of microglia and oligodendrocytes in the cerebral cortex of adult offspring. NP exposure caused anxiety- and depressive-like behaviors in adult mice. Collectively, these findings suggest that maternal NP exposure negatively affects the brain development in adult offspring mice.
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Affiliation(s)
- Seung Hyun Lee
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea
- Institute for Future Earth, Pusan National University, Busan, Republic of Korea
| | - Hyun Seung Shin
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea
- Institute for Future Earth, Pusan National University, Busan, Republic of Korea
| | - Yun Hee So
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea
- Institute for Future Earth, Pusan National University, Busan, Republic of Korea
| | - Dong Hun Lee
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea
- Institute for Future Earth, Pusan National University, Busan, Republic of Korea
| | | | - Eun-Hee Lee
- Department of Microbiology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea
| | - Eui-Man Jung
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea
- Institute for Future Earth, Pusan National University, Busan, Republic of Korea
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Li X, Shan J, Liu X, Huang Z, Xu G, Ren L. Microglial repopulation induced by PLX3397 protects against ischemic brain injury by suppressing neuroinflammation in aged mice. Int Immunopharmacol 2024; 138:112473. [PMID: 38943977 DOI: 10.1016/j.intimp.2024.112473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 05/31/2024] [Accepted: 06/10/2024] [Indexed: 07/01/2024]
Abstract
As the resident immune cells in the central nervous system, microglia exhibit a 'sensitized' or 'primed' phenotype with dystrophic morphology and dysregulated functions in aged brains. Although studies have demonstrated the inflammatory profile of aged microglia in several neurological diseases, this issue is largely uncertain in stroke. Consequently, this study investigated the effects of primed and repopulated microglia on post-ischemic brain injury in aged mice. We replaced primed microglia with newly repopulated microglia through pharmacological administration and withdrawal of the colony-stimulating factor 1 receptor (CSF1R) inhibitor, PLX3397. Further, we performed a series of behavioral tests and flow cytometry in mouse models of middle cerebral artery occlusion (MCAO) to study the effects of microglial replacement on ischemic injury in the aged brain. With depletion and subsequent repopulation of microglia in MCAO mice, microglial replacement in aged mice improved neurological function and decreased brain infarction. This protective effect was accompanied by the reduction of peripheral immune cells infiltrating into brains. We showed that the repopulated microglia expressed elevated neuroprotective factors (including Cluster of Differentiation 206, transforming growth factor-β, and interleukin-10) and diminished expression of inflammatory markers (including Cluster of Differentiation 86, interleukin-6, and tumor necrosis factor α). Moreover, microglial replacement protected the blood-brain barrier and relieved neuronal death in aged mice subjected to 60 min of MCAO. These results imply that the replacement of microglia in the aged brain may alleviate brain damage and neuroinflammation, and therefore, ischemic brain damage. Thus, targeting microglia could be a promising therapeutic strategy for ischemic stroke.
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Affiliation(s)
- Xiuping Li
- Department of Neurology, Shenzhen Institute of Translational Medicine, First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen 518060, China; Department of Neurology, First Affiliated Hospital, Shanxi Medical University, Taiyuan 030000, China
| | - Jingyang Shan
- Department of Neurology, Shenzhen Institute of Translational Medicine, First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen 518060, China
| | - Xia Liu
- Department of Neurology, Shenzhen Institute of Translational Medicine, First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen 518060, China
| | - Zhengzheng Huang
- Department of Neurology, Shenzhen Institute of Translational Medicine, First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen 518060, China
| | - Gelin Xu
- Department of Neurology, Shenzhen Institute of Translational Medicine, First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen 518060, China.
| | - Lijie Ren
- Department of Neurology, Shenzhen Institute of Translational Medicine, First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen 518060, China.
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Du S, Drieu A, Cheng Y, Storck SE, Rustenhoven J, Mamuladze T, Bhattarai B, Brioschi S, Nguyen K, Ou F, Cao J, Rodrigues PF, Smirnov I, DeNardo D, Ginhoux F, Cella M, Colonna M, Kipnis J. Brain-Engrafted Monocyte-derived Macrophages from Blood and Skull-Bone Marrow Exhibit Distinct Identities from Microglia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.08.606900. [PMID: 39211090 PMCID: PMC11361186 DOI: 10.1101/2024.08.08.606900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Microglia are thought to originate exclusively from primitive macrophage progenitors in the yolk sac (YS) and to persist throughout life without much contribution from definitive hematopoiesis. Here, using lineage tracing, pharmacological manipulation, and RNA-sequencing, we elucidated the presence and characteristics of monocyte-derived macrophages (MDMs) in the brain parenchyma at baseline and during microglia repopulation, and defined the core transcriptional signatures of brain-engrafted MDMs. Lineage tracing mouse models revealed that MDMs transiently express CD206 during brain engraftment as CD206 + microglia precursors in the YS. We found that brain-engrafted MDMs exhibit transcriptional and epigenetic characteristics akin to meningeal macrophages, likely due to environmental imprinting within the meningeal space. Utilizing parabiosis and skull transplantation, we demonstrated that monocytes from both peripheral blood and skull bone marrow can repopulate microglia-depleted brains. Our results reveal the heterogeneous origins and cellular dynamics of brain parenchymal macrophages at baseline and in models of microglia depletion.
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Kodali M, Madhu LN, Somayaji Y, Attaluri S, Huard C, Panda PK, Shankar G, Rao S, Shuai B, Gonzalez JJ, Oake C, Hering C, Babu RS, Kotian S, Shetty AK. Residual Microglia Following Short-term PLX5622 Treatment in 5xFAD Mice Exhibit Diminished NLRP3 Inflammasome and mTOR Signaling, and Enhanced Autophagy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.11.603157. [PMID: 39071343 PMCID: PMC11275929 DOI: 10.1101/2024.07.11.603157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Chronic neuroinflammation represents a prominent hallmark of Alzheimer's disease (AD). While moderately activated microglia are pivotal in clearing amyloid beta (Aβ), hyperactivated microglia perpetuate neuroinflammation. Prior investigations have indicated that the elimination of ∼80% of microglia through a month-long inhibition of the colony-stimulating factor 1 receptor (CSF1R) during the advanced stage of neuroinflammation in 5xFamilial AD (5xFAD) mice mitigates synapse loss and neurodegeneration without impacting Aβ levels. Furthermore, prolonged CSF1R inhibition diminished the development of parenchymal plaques. Nonetheless, the immediate effects of short-term CSF1R inhibition during the early stages of neuroinflammation on residual microglial phenotype or metabolic fitness are unknown. Therefore, we investigated the effects of 10-day CSF1R inhibition in three-month-old female 5xFAD mice, a stage characterized by the onset of neuroinflammation and minimal Aβ plaques. We observed ∼65% microglia depletion in the hippocampus and cerebral cortex. The leftover microglia demonstrated a noninflammatory phenotype, with highly branched and ramified processes and reduced NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome complexes. Moreover, plaque-associated microglia were reduced in number with diminished Clec7a (dectin-1) expression. Additionally, both microglia and neurons displayed reduced mechanistic target of rapamycin (mTOR) signaling and autophagy. Biochemical assays validated the inhibition of NLRP3 inflammasome activation, decreased mTOR signaling, and enhanced autophagy. However, short-term CSF1R inhibition did not influence Aβ plaques, soluble Aβ-42 levels, or hippocampal neurogenesis. Thus, short-term CSF1R inhibition during the early stages of neuroinflammation in 5xFAD mice promotes the retention of homeostatic microglia with diminished inflammasome activation and mTOR signaling, alongside increased autophagy.
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Li H, Watkins LR, Wang X. Microglia in neuroimmunopharmacology and drug addiction. Mol Psychiatry 2024; 29:1912-1924. [PMID: 38302560 DOI: 10.1038/s41380-024-02443-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 02/03/2024]
Abstract
Drug addiction is a chronic and debilitating disease that is considered a global health problem. Various cell types in the brain are involved in the progression of drug addiction. Recently, the xenobiotic hypothesis has been proposed, which frames substances of abuse as exogenous molecules that are responded to by the immune system as foreign "invaders", thus triggering protective inflammatory responses. An emerging body of literature reveals that microglia, the primary resident immune cells in the brain, play an important role in the progression of addiction. Repeated cycles of drug administration cause a progressive, persistent induction of neuroinflammation by releasing microglial proinflammatory cytokines and their metabolic products. This contributes to drug addiction via modulation of neuronal function. In this review, we focus on the role of microglia in the etiology of drug addiction. Then, we discuss the dynamic states of microglia and the correlative and causal evidence linking microglia to drug addiction. Finally, possible mechanisms of how microglia sense drug-related stimuli and modulate the addiction state and how microglia-targeted anti-inflammation therapies affect addiction are reviewed. Understanding the role of microglia in drug addiction may help develop new treatment strategies to fight this devastating societal challenge.
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Affiliation(s)
- Hongyuan Li
- Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China
| | - Linda R Watkins
- Department of Psychology and Neuroscience, and the Center for Neuroscience, University of Colorado Boulder, Boulder, CO, 80309, USA
| | - Xiaohui Wang
- Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, 230026, China.
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China.
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Song Y, Liao Y, Liu T, Chen Y, Wang F, Zhou Z, Zhang W, Li J. Microglial repopulation restricts ocular inflammation and choroidal neovascularization in mice. Front Immunol 2024; 15:1366841. [PMID: 38711521 PMCID: PMC11070532 DOI: 10.3389/fimmu.2024.1366841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Accepted: 04/04/2024] [Indexed: 05/08/2024] Open
Abstract
Introduction Age-related macular degeneration (AMD) is a prevalent, chronic and progressive retinal degenerative disease characterized by an inflammatory response mediated by activated microglia accumulating in the retina. In this study, we demonstrate the therapeutically effects and the underlying mechanisms of microglial repopulation in the laser-induced choroidal neovascularization (CNV) model of exudative AMD. Methods The CSF1R inhibitor PLX3397 was used to establish a treatment paradigm for microglial repopulation in the retina. Neovascular leakage and neovascular area were examined by fundus fluorescein angiography (FFA) and immunostaining of whole-mount RPE-choroid-sclera complexes in CNV mice receiving PLX3397. Altered cellular senescence was measured by beta-galactosidase (SA-β-gal) activity and p16INK4a expression. The effect and mechanisms of repopulated microglia on leukocyte infiltration and the inflammatory response in CNV lesions were analyzed. Results We showed that ten days of the CSF1R inhibitor PLX3397 treatment followed by 11 days of drug withdrawal was sufficient to stimulate rapid repopulation of the retina with new microglia. Microglial repopulation attenuated pathological choroid neovascularization and dampened cellular senescence in CNV lesions. Repopulating microglia exhibited lower levels of activation markers, enhanced phagocytic function and produced fewer cytokines involved in the immune response, thereby ameliorating leukocyte infiltration and attenuating the inflammatory response in CNV lesions. Discussion The microglial repopulation described herein are therefore a promising strategy for restricting inflammation and choroidal neovascularization, which are important players in the pathophysiology of AMD.
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Affiliation(s)
- Yinting Song
- Department of Ophthalmology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
| | - Yuefeng Liao
- Department of Ophthalmology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
| | - Tong Liu
- Department of Ophthalmology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
| | - Yanxian Chen
- Department of Ophthalmology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
- Experimental Ophthalmology, School of Optometry, The Hong Kong Polytechnic University, HongKong, Hong Kong SAR, China
| | - Fei Wang
- Department of Ophthalmology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
| | - Zixia Zhou
- Department of Ophthalmology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
| | - Weili Zhang
- Department of Ophthalmology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
| | - Jinying Li
- Department of Ophthalmology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
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Pallarés-Moratalla C, Bergers G. The ins and outs of microglial cells in brain health and disease. Front Immunol 2024; 15:1305087. [PMID: 38665919 PMCID: PMC11043497 DOI: 10.3389/fimmu.2024.1305087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 03/19/2024] [Indexed: 04/28/2024] Open
Abstract
Microglia are the brain's resident macrophages that play pivotal roles in immune surveillance and maintaining homeostasis of the Central Nervous System (CNS). Microglia are functionally implicated in various cerebrovascular diseases, including stroke, aneurysm, and tumorigenesis as they regulate neuroinflammatory responses and tissue repair processes. Here, we review the manifold functions of microglia in the brain under physiological and pathological conditions, primarily focusing on the implication of microglia in glioma propagation and progression. We further review the current status of therapies targeting microglial cells, including their re-education, depletion, and re-population approaches as therapeutic options to improve patient outcomes for various neurological and neuroinflammatory disorders, including cancer.
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Bakhtazad S, Ghotbeddin Z, Tabandeh MR, Rahimi K. Alpha-pinene ameliorate behavioral deficit induced by early postnatal hypoxia in the rat: study the inflammatory mechanism. Sci Rep 2024; 14:6416. [PMID: 38494527 PMCID: PMC10944845 DOI: 10.1038/s41598-024-56756-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 03/11/2024] [Indexed: 03/19/2024] Open
Abstract
Neonatal hypoxia has a negative impact on the developing brain during the sensitive period. Inflammation plays a key role in the physiological response to hypoxic stress. Considering the anti-inflammatory properties of alpha-pinene, which has received a lot of attention in recent years, in this research we focused on the impact of alpha-pinene on the behavioral responses and proinflammatory factors in rats subjected to the neonatal hypoxia. This study involved Wistar rats (7-day-old) that were divided into six experimental groups, including a control group, groups receiving different doses of alpha-pinene (5 and 10 mg/kg), a hypoxia group receiving 7% O2 and 93% N2, 90 min duration for 7 days, and groups receiving alpha-pinene 30 min before hypoxia. All injections were done intraperitoneally. The rats were evaluated for proinflammatory factors 24 h after exposure to hypoxia (PND14) and at the end of the behavioral test (PND54). The results showed that hypoxia led to decreased motor activity, coordination, and memory, as well as increased inflammation. However, the rats that received alpha-pinene showed improved behavioral responses and reduced inflammation compared to the hypoxia group (all cases p < 0.05). This suggests that alpha-pinene may have a protective effect via anti-inflammatory properties against the negative impacts of hypoxia on the developing brain.
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Affiliation(s)
- Sharareh Bakhtazad
- Department of Basic Sciences, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Zohreh Ghotbeddin
- Department of Basic Sciences, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
- Stem Cell and Transgenic Technology Research Center, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
| | - Mohammad Reza Tabandeh
- Stem Cell and Transgenic Technology Research Center, Shahid Chamran University of Ahvaz, Ahvaz, Iran
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Kaveh Rahimi
- Department of Basic Sciences, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
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Boland R, Kokiko-Cochran ON. Deplete and repeat: microglial CSF1R inhibition and traumatic brain injury. Front Cell Neurosci 2024; 18:1352790. [PMID: 38450286 PMCID: PMC10915023 DOI: 10.3389/fncel.2024.1352790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 01/25/2024] [Indexed: 03/08/2024] Open
Abstract
Traumatic brain injury (TBI) is a public health burden affecting millions of people. Sustained neuroinflammation after TBI is often associated with poor outcome. As a result, increased attention has been placed on the role of immune cells in post-injury recovery. Microglia are highly dynamic after TBI and play a key role in the post-injury neuroinflammatory response. Therefore, microglia represent a malleable post-injury target that could substantially influence long-term outcome after TBI. This review highlights the cell specific role of microglia in TBI pathophysiology. Microglia have been manipulated via genetic deletion, drug inhibition, and pharmacological depletion in various pre-clinical TBI models. Notably, colony stimulating factor 1 (CSF1) and its receptor (CSF1R) have gained much traction in recent years as a pharmacological target on microglia. CSF1R is a transmembrane tyrosine kinase receptor that is essential for microglia proliferation, differentiation, and survival. Small molecule inhibitors targeting CSF1R result in a swift and effective depletion of microglia in rodents. Moreover, discontinuation of the inhibitors is sufficient for microglia repopulation. Attention is placed on summarizing studies that incorporate CSF1R inhibition of microglia. Indeed, microglia depletion affects multiple aspects of TBI pathophysiology, including neuroinflammation, oxidative stress, and functional recovery with measurable influence on astrocytes, peripheral immune cells, and neurons. Taken together, the data highlight an important role for microglia in sustaining neuroinflammation and increasing risk of oxidative stress, which lends to neuronal damage and behavioral deficits chronically after TBI. Ultimately, the insights gained from CSF1R depletion of microglia are critical for understanding the temporospatial role that microglia develop in mediating TBI pathophysiology and recovery.
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Affiliation(s)
- Rebecca Boland
- Department of Neuroscience, College of Medicine, Chronic Brain Injury Program, Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, United States
| | - Olga N Kokiko-Cochran
- Department of Neuroscience, College of Medicine, Chronic Brain Injury Program, Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, United States
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Adhikari A, Chauhan K, Adhikari M, Tiwari AK. Colony Stimulating Factor-1 Receptor: An emerging target for neuroinflammation PET imaging and AD therapy. Bioorg Med Chem 2024; 100:117628. [PMID: 38330850 DOI: 10.1016/j.bmc.2024.117628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 01/01/2024] [Accepted: 01/29/2024] [Indexed: 02/10/2024]
Abstract
Although neuroinflammation is a significant pathogenic feature of many neurologic disorders, its precise function in-vivo is still not completely known. PET imaging enables the longitudinal examination, quantification, and tracking of different neuroinflammation biomarkers in living subjects. Particularly, PET imaging of Microglia, specialised dynamic immune cells crucial for maintaining brain homeostasis in central nervous system (CNS), is crucial for staging the neuroinflammation. Colony Stimulating Factor- 1 Receptor (CSF-1R) PET imaging is a novel method for the quantification of neuroinflammation. CSF-1R is mainly expressed on microglia, and neurodegenerative disorders greatly up-regulate its expression. The present review primarily focuses on the development, pros and cons of all the CSF-1R PET tracers reported for neuroinflammation imaging. Apart from neuroinflammation imaging, CSF-1R inhibitors are also reported for the therapy of neurodegenerative diseases such as Alzheimer's disease (AD). AD is a prevalent, advancing, and fatal neurodegenerative condition that have the characteristic feature of persistent neuroinflammation and primarily affects the elderly. The aetiology of AD is profoundly influenced by amyloid-beta (Aβ) plaques, intracellular neurofibrillary tangles, and microglial dysfunction. Increasing evidence suggests that CSF-1R inhibitors (CSF-1Ri) can be helpful in preclinical models of neurodegenerative diseases. This review article also summarises the most recent developments of CSF-1Ri-based therapy for AD.
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Affiliation(s)
- Anupriya Adhikari
- Department of Chemistry, Graphic Era Hill University, Clement Town, Dehradun, Uttarakhand, India.
| | - Kanchan Chauhan
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera, Tijuana-Ensenada, Baja California 22860, Mexico
| | - Manish Adhikari
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Anjani K Tiwari
- Department of Chemistry, Babasaheb, Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
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12
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Weyer MP, Strehle J, Schäfer MKE, Tegeder I. Repurposing of pexidartinib for microglia depletion and renewal. Pharmacol Ther 2024; 253:108565. [PMID: 38052308 DOI: 10.1016/j.pharmthera.2023.108565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 11/20/2023] [Accepted: 11/22/2023] [Indexed: 12/07/2023]
Abstract
Pexidartinib (PLX3397) is a small molecule receptor tyrosine kinase inhibitor of colony stimulating factor 1 receptor (CSF1R) with moderate selectivity over other members of the platelet derived growth factor receptor family. It is approved for treatment of tenosynovial giant cell tumors (TGCT). CSF1R is highly expressed by microglia, which are macrophages of the central nervous system (CNS) that defend the CNS against injury and pathogens and contribute to synapse development and plasticity. Challenged by pathogens, apoptotic cells, debris, or inflammatory molecules they adopt a responsive state to propagate the inflammation and eventually return to a homeostatic state. The phenotypic switch may fail, and disease-associated microglia contribute to the pathophysiology in neurodegenerative or neuropsychiatric diseases or long-lasting detrimental brain inflammation after brain, spinal cord or nerve injury or ischemia/hemorrhage. Microglia also contribute to the growth permissive tumor microenvironment of glioblastoma (GBM). In rodents, continuous treatment for 1-2 weeks via pexidartinib food pellets leads to a depletion of microglia and subsequent repopulation from the remaining fraction, which is aided by peripheral monocytes that search empty niches for engraftment. The putative therapeutic benefit of such microglia depletion or forced renewal has been assessed in almost any rodent model of CNS disease or injury or GBM with heterogeneous outcomes, but a tendency of partial beneficial effects. So far, microglia monitoring e.g. via positron emission imaging is not standard of care for patients receiving Pexidartinib (e.g. for TGCT), so that the depletion and repopulation efficiency in humans is still largely unknown. Considering the virtuous functions of microglia, continuous depletion is likely no therapeutic option but short-lasting transient partial depletion to stimulate microglia renewal or replace microglia in genetic disease in combination with e.g. stem cell transplantation or as part of a multimodal concept in treatment of glioblastoma appears feasible. The present review provides an overview of the preclinical evidence pro and contra microglia depletion as a therapeutic approach.
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Affiliation(s)
- Marc-Philipp Weyer
- Institute of Clinical Pharmacology, Goethe-University Frankfurt, Faculty of Medicine, Frankfurt, Germany
| | - Jenny Strehle
- Department of Anesthesiology, University Medical Center Johannes Gutenberg-University Mainz, Germany
| | - Michael K E Schäfer
- Department of Anesthesiology, University Medical Center Johannes Gutenberg-University Mainz, Germany
| | - Irmgard Tegeder
- Institute of Clinical Pharmacology, Goethe-University Frankfurt, Faculty of Medicine, Frankfurt, Germany.
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13
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Frumer GR, Shin SH, Jung S, Kim JS. Not just Glia-Dissecting brain macrophages in the mouse. Glia 2024; 72:5-18. [PMID: 37501579 DOI: 10.1002/glia.24445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 07/05/2023] [Accepted: 07/14/2023] [Indexed: 07/29/2023]
Abstract
Macrophages have emerged as critical cellular components of the central nervous system (CNS), promoting development, maintenance, and immune defense of the CNS. Here we will review recent advances in our understanding of brain macrophage heterogeneity, including microglia and border-associated macrophages, focusing on the mouse. Emphasis will be given to the discussion of strengths and limitations of the experimental approaches that have led to the recent insights and hold promise to further deepen our mechanistic understanding of brain macrophages that might eventually allow to harness their activities for the management of CNS pathologies.
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Affiliation(s)
- Gal Ronit Frumer
- Department of Immunology and Regenerative Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Sun-Hye Shin
- Department of Immunology and Regenerative Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Steffen Jung
- Department of Immunology and Regenerative Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Jung-Seok Kim
- Department of Immunology and Regenerative Biology, Weizmann Institute of Science, Rehovot, Israel
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14
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Kim JD, Copperi F, Diano S. Microglia in Central Control of Metabolism. Physiology (Bethesda) 2024; 39:0. [PMID: 37962895 PMCID: PMC11283896 DOI: 10.1152/physiol.00021.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 11/12/2023] [Accepted: 11/12/2023] [Indexed: 11/15/2023] Open
Abstract
Beyond their role as brain immune cells, microglia act as metabolic sensors in response to changes in nutrient availability, thus playing a role in energy homeostasis. This review highlights the evidence and challenges of studying the role of microglia in metabolism regulation.
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Affiliation(s)
- Jung Dae Kim
- Institute of Human Nutrition, Columbia University Irving Medical Center, New York, New York, United States
| | - Francesca Copperi
- Institute of Human Nutrition, Columbia University Irving Medical Center, New York, New York, United States
| | - Sabrina Diano
- Institute of Human Nutrition, Columbia University Irving Medical Center, New York, New York, United States
- Department of Molecular Pharmacology and Therapeutics, Columbia University Irving Medical Center, New York, New York, United States
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, New York, United States
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15
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Kim JS, Jung S. Visualization, Fate Mapping, Ablation, and Mutagenesis of Microglia in the Mouse Brain. ADVANCES IN NEUROBIOLOGY 2024; 37:53-63. [PMID: 39207686 DOI: 10.1007/978-3-031-55529-9_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Since the classical studies of Pío del Río-Hortega, microglia research has come a long way. In particular, recent advances in bulk and single-cell (sc) transcriptomics have yielded many fascinating new insights into these intriguing immune cells at the interface with the central nervous system (CNS), both in small animal models and human samples. In parallel, tools developed by advanced mouse genetics have revealed the unique ontogeny of microglia and their striking dynamic interactions with other cells in the brain parenchyma. In this chapter, we will discuss various applications of the Cre/loxP-based approach that have enabled the study of microglia in their physiological context of the mouse brain. We will highlight selected key findings that have shaped our current understanding of these cells and discuss the technical intricacies of the Cre/loxP approach and some remaining challenges.
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Affiliation(s)
- Jung-Seok Kim
- Department of Immunology and Regenerative Biology (IRB), Weizmann Institute of Science, Rehovot, Israel.
| | - Steffen Jung
- Department of Immunology and Regenerative Biology (IRB), Weizmann Institute of Science, Rehovot, Israel
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16
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He Y, Liu T, He Q, Ke W, Li X, Du J, Deng S, Shu Z, Wu J, Yang B, Wang Y, Mao Y, Rao Y, Shu Y, Peng B. Microglia facilitate and stabilize the response to general anesthesia via modulating the neuronal network in a brain region-specific manner. eLife 2023; 12:RP92252. [PMID: 38131301 PMCID: PMC10746144 DOI: 10.7554/elife.92252] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023] Open
Abstract
General anesthesia leads to a loss of consciousness and an unrousable state in patients. Although general anesthetics are widely used in clinical practice, their underlying mechanisms remain elusive. The potential involvement of nonneuronal cells is unknown. Microglia are important immune cells in the central nervous system (CNS) that play critical roles in CNS function and dysfunction. We unintentionally observed delayed anesthesia induction and early anesthesia emergence in microglia-depleted mice. We found that microglial depletion differentially regulates neuronal activities by suppressing the neuronal network of anesthesia-activated brain regions and activating emergence-activated brain regions. Thus, microglia facilitate and stabilize the anesthesia status. This influence is not mediated by dendritic spine plasticity. Instead, it relies on the activation of microglial P2Y12 and subsequent calcium influx, which facilitates the general anesthesia response. Together, we elucidate the regulatory role of microglia in general anesthesia, extending our knowledge of how nonneuronal cells modulate neuronal activities.
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Affiliation(s)
- Yang He
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Taohui Liu
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Quansheng He
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Wei Ke
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Xiaoyu Li
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Jinjin Du
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
- School of Basic Medical Sciences, Jinzhou Medical UniversityJinzhouChina
| | - Suixin Deng
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Zhenfeng Shu
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Jialin Wu
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Baozhi Yang
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
- School of Basic Medical Sciences, Jinzhou Medical UniversityJinzhouChina
| | - Yuqing Wang
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
- School of Basic Medical Sciences, Jinzhou Medical UniversityJinzhouChina
| | - Ying Mao
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Yanxia Rao
- Department of Neurology, Zhongshan Hospital, Department of Laboratory Animal Science, MOE Frontiers Center for Brain Science, Fudan UniversityShanghaiChina
| | - Yousheng Shu
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Bo Peng
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
- Co-Innovation Center of Neurodegeneration, Nantong UniversityNantongChina
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17
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Perna A, Montine KS, White LR, Montine TJ, Cholerton BA. Paradigm Shift: Multiple Potential Pathways to Neurodegenerative Dementia. Neurotherapeutics 2023; 20:1641-1652. [PMID: 37733209 PMCID: PMC10684852 DOI: 10.1007/s13311-023-01441-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2023] [Indexed: 09/22/2023] Open
Abstract
Neurodegenerative dementia can result from multiple underlying abnormalities, including neurotransmitter imbalances, protein aggregation, and other neurotoxic events. A major complication in identifying effective treatment targets is the frequent co-occurrence of multiple neurodegenerative processes, occurring either in parallel or sequentially. The path towards developing effective treatments for Alzheimer's disease (AD) and other dementias has been relatively slow and until recently has focused on disease symptoms. Aducanumab and lecanemab, recently approved by the FDA, are meant to target disease structures but have only modest benefit on symptom progression and remain unproven in reversing or preventing dementia. A third, donanemab, appears more promising but awaits FDA approval. Ongoing trials include potential cognition enhancers, new combinations of known drugs for synergistic effects, prodrugs with less toxicity, and increasing interest in drugs targeting neuroinflammation or microbiome. Scientific and technological advances offer the opportunity to move in new therapy directions, such as modifying microglia to prevent or suppress underlying disease. A major challenge, however, is that underlying comorbidities likely influence the effectiveness of therapies. Indeed, the full range of comorbidity, today only definitively identified postmortem, likely contributes to failed clinical trials and overmedication of older adults, since it is difficult to exclude (during life) people unlikely to respond. Our current knowledge thus signals that a paradigm shift towards individualized and multimodal treatments is necessary to effectively advance the field of dementia therapeutics.
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Affiliation(s)
- Amalia Perna
- Department of Pathology, Stanford University, 300 Pasteur Dr., Stanford, CA, 94305, USA.
| | - Kathleen S Montine
- Department of Pathology, Stanford University, 300 Pasteur Dr., Stanford, CA, 94305, USA
| | - Lon R White
- Pacific Health Research and Education Institute, Honolulu, HI, USA
| | - Thomas J Montine
- Department of Pathology, Stanford University, 300 Pasteur Dr., Stanford, CA, 94305, USA
| | - Brenna A Cholerton
- Department of Pathology, Stanford University, 300 Pasteur Dr., Stanford, CA, 94305, USA
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18
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Li X, Li Y, Jin Y, Zhang Y, Wu J, Xu Z, Huang Y, Cai L, Gao S, Liu T, Zeng F, Wang Y, Wang W, Yuan TF, Tian H, Shu Y, Guo F, Lu W, Mao Y, Mei X, Rao Y, Peng B. Transcriptional and epigenetic decoding of the microglial aging process. NATURE AGING 2023; 3:1288-1311. [PMID: 37697166 PMCID: PMC10570141 DOI: 10.1038/s43587-023-00479-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 08/03/2023] [Indexed: 09/13/2023]
Abstract
As important immune cells, microglia undergo a series of alterations during aging that increase the susceptibility to brain dysfunctions. However, the longitudinal characteristics of microglia remain poorly understood. In this study, we mapped the transcriptional and epigenetic profiles of microglia from 3- to 24-month-old mice. We first discovered unexpected sex differences and identified age-dependent microglia (ADEM) genes during the aging process. We then compared the features of aging and reactivity in female microglia at single-cell resolution and epigenetic level. To dissect functions of aged microglia excluding the influence from other aged brain cells, we established an accelerated microglial turnover model without directly affecting other brain cells. By this model, we achieved aged-like microglia in non-aged brains and confirmed that aged-like microglia per se contribute to cognitive decline. Collectively, our work provides a comprehensive resource for decoding the aging process of microglia, shedding light on how microglia maintain brain functions.
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Affiliation(s)
- Xiaoyu Li
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Yuxin Li
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Yuxiao Jin
- Department of Neurology, Zhongshan Hospital, Department of Laboratory Animal Science, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Yuheng Zhang
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Jingchuan Wu
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Zhen Xu
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Yubin Huang
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Lin Cai
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
- Department of Neurology, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shuai Gao
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Taohui Liu
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Fanzhuo Zeng
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
- Department of Orthopedics, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, China
| | - Yafei Wang
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Wenxu Wang
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Ti-Fei Yuan
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hengli Tian
- Department of Neurology, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yousheng Shu
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Feifan Guo
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Wei Lu
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China
| | - Ying Mao
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Xifan Mei
- Department of Orthopedics, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, China
| | - Yanxia Rao
- Department of Neurology, Zhongshan Hospital, Department of Laboratory Animal Science, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China.
| | - Bo Peng
- Department of Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, Fudan University, Shanghai, China.
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China.
- Co-Innovation Center of Neurodegeneration, Nantong University, Nantong, China.
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19
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Yan L, Xuan FL, Chen S, Gou M, Chen W, Li Y, Wang Z, Wang L, Xie T, Fan F, Zharkovsky A, Tan Y, Tian L. Replenished microglia partially rescue schizophrenia-related stress response. Front Cell Neurosci 2023; 17:1254923. [PMID: 37771931 PMCID: PMC10522857 DOI: 10.3389/fncel.2023.1254923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 08/15/2023] [Indexed: 09/30/2023] Open
Abstract
Background Microglia play an important role in the maintenance of brain and behavioral homeostasis. The protective effect of microglial replenishment was reported in neurological diseases, but whether microglial therapy would benefit psychiatric disorders such as schizophrenia has been unclear. As schizophrenia is a stress-vulnerable disorder and psychosocial stress promotes inflammation and microglial activation, we aim to understand how microglial replenishment works in stress-associated schizophrenia. Methods We used a CSF1R-mediated pharmacological approach to study repopulated microglia (repMg) in a cohort of mice (n = 10/group) undergoing chronic unpredictable stress (CUS). We further studied a cohort of first-episode schizophrenia (FES, n = 74) patients who had higher perceived stress scores (PSS) than healthy controls (HCs, n = 68). Results Reborn microglia attenuated CUS-induced learned hopelessness and social withdrawal but not anxiety in mice. Compared to control, CUS- or repMg-induced differentially expressed genes (DEGs) in the prefrontal cortex regulated nervous system development and axonal guidance. CUS also caused microglial hyper-ramification and increased engulfment of synaptophysin and vesicular glutamate transporter-2 by microglia and astrocytes, which were recovered in CUS + repMg (all p < 0.05). Moreover, FES patients had smaller hippocampal fimbria than HCs (p < 1e-7), which were negatively associated with PSS (r = -0.397, p = 0.003). Blood DEGs involved in immune system development were also associated with PSS and the right fimbria more prominently in FES patients than HCs (Zr, p < 0.0001). The KCNQ1 was a partial mediator between PSS and fimbria size (β = -0.442, 95% CI: -1.326 ~ -0.087). Conclusion Microglial replenishment may potentially benefit psychiatric disorders such as schizophrenia.
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Affiliation(s)
- Ling Yan
- Institute of Biomedicine and Translational Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
| | - Fang-Ling Xuan
- Institute of Biomedicine and Translational Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
| | - Song Chen
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
| | - Mengzhuang Gou
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
| | - Wenjin Chen
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
| | - Yanli Li
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
| | - Zhiren Wang
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
| | - Leilei Wang
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
| | - Ting Xie
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
| | - Fengmei Fan
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
| | - Alexander Zharkovsky
- Institute of Biomedicine and Translational Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
| | - Yunlong Tan
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
| | - Li Tian
- Institute of Biomedicine and Translational Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
- Psychiatry Research Centre, Beijing Huilongguan Hospital, Peking University Health Science Center, Beijing, China
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20
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Wang Q, Wang YY, Pu WJ, Ma X, Ni RJ. Dynamic changes in microglia in the mouse hippocampus during administration and withdrawal of the CSF1R inhibitor PLX3397. J Anat 2023; 243:394-403. [PMID: 37038887 PMCID: PMC10439370 DOI: 10.1111/joa.13874] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 02/01/2023] [Accepted: 03/28/2023] [Indexed: 04/12/2023] Open
Abstract
Pexidartinib (PLX3397), a colony-stimulating factor-1 receptor (CSF1R) inhibitor, is currently in phase 1-3 clinical trials as a treatment for a variety of tumours. CSF1R signalling regulates the development, survival and maintenance of microglia, the resident brain innate immune cells. In this study, we examined the effects of PLX3397 in the drinking water of mice on microglia in the hippocampus using ionized calcium-binding adapter molecule 1 (Iba1, a microglial marker) immunocytochemistry. A high concentration of PLX3397 (1 mg/mL) significantly decreased the density of Iba1-immunoreactive cells after 7 days of exposure, but a low concentration of PLX3397 (0.5 mg/mL) did not. In addition, both low and high concentrations of PLX3397 significantly increased the intersection number, total length and maximum length of microglial processes in male mice. PLX3397 administered for 21 days eliminated microglia with 78% efficiency in males and 84% efficiency in females. Significant increases in microglial processes were found after both seven and 21 days of PLX3397 exposure in males, whereas decreases in microglial processes were observed after both 14 and 21 days of exposure in females. After PLX3397 withdrawal following its administration for 14 days in males, the soma size quickly returned to normal levels within a week. However, the microglial density, intersection number and total length of microglial processes after 3 days of recovery stabilized to untreated levels. In summary, these findings provide detailed insight into the dynamic changes in microglial number and morphology in the hippocampus in a dose- and time-dependent manner after PLX3397 treatment and withdrawal.
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Affiliation(s)
- Qirun Wang
- Psychiatric Laboratory and Mental Health Center, West China Hospital, Sichuan University, Chengdu, China
- Sichuan Clinical Medical Research Center for Mental Disorders, Chengdu, China
| | - Yi-Yan Wang
- Psychiatric Laboratory and Mental Health Center, West China Hospital, Sichuan University, Chengdu, China
- Sichuan Clinical Medical Research Center for Mental Disorders, Chengdu, China
| | - Wen-Jun Pu
- Psychiatric Laboratory and Mental Health Center, West China Hospital, Sichuan University, Chengdu, China
- Sichuan Clinical Medical Research Center for Mental Disorders, Chengdu, China
| | - Xiaohong Ma
- Psychiatric Laboratory and Mental Health Center, West China Hospital, Sichuan University, Chengdu, China
- Sichuan Clinical Medical Research Center for Mental Disorders, Chengdu, China
| | - Rong-Jun Ni
- Psychiatric Laboratory and Mental Health Center, West China Hospital, Sichuan University, Chengdu, China
- Sichuan Clinical Medical Research Center for Mental Disorders, Chengdu, China
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21
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Gan C, Li W, Xu J, Pang L, Tang L, Yu S, Li A, Ge H, Huang R, Cheng H. Advances in the study of the molecular biological mechanisms of radiation-induced brain injury. Am J Cancer Res 2023; 13:3275-3299. [PMID: 37693137 PMCID: PMC10492106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Accepted: 07/12/2023] [Indexed: 09/12/2023] Open
Abstract
Radiation therapy is one of the most commonly used treatments for head and neck cancers, but it often leads to radiation-induced brain injury. Patients with radiation-induced brain injury have a poorer quality of life, and no effective treatments are available. The pathogenesis of this condition is unknown. This review summarizes the molecular biological mechanism of radiation-induced brain injury and provides research directions for future studies. The molecular mechanisms of radiation-induced brain injury are diverse and complex. Radiation-induced chronic neuroinflammation, destruction of the blood-brain barrier, oxidative stress, neuronal damage, and physiopathological responses caused by specific exosome secretion lead to radiation-induced brain injury.
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Affiliation(s)
- Chen Gan
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
| | - Wen Li
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
| | - Jian Xu
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
| | - Lulian Pang
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
| | - Lingxue Tang
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
| | - Sheng Yu
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
| | - Anlong Li
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
| | - Han Ge
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
| | - Runze Huang
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
| | - Huaidong Cheng
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Anhui Medical UniversityHefei, Anhui, China
- Department of Oncology, Shenzhen Hospital of Southern Medical UniversityShenzhen, Guangdong, China
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22
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Melchiorri D, Merlo S, Micallef B, Borg JJ, Dráfi F. Alzheimer's disease and neuroinflammation: will new drugs in clinical trials pave the way to a multi-target therapy? Front Pharmacol 2023; 14:1196413. [PMID: 37332353 PMCID: PMC10272781 DOI: 10.3389/fphar.2023.1196413] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/02/2023] [Indexed: 06/20/2023] Open
Abstract
Despite extensive research, no disease-modifying therapeutic option, able to prevent, cure or halt the progression of Alzheimer's disease [AD], is currently available. AD, a devastating neurodegenerative pathology leading to dementia and death, is characterized by two pathological hallmarks, the extracellular deposits of amyloid beta (Aβ) and the intraneuronal deposits of neurofibrillary tangles (NFTs) consisting of altered hyperphosphorylated tau protein. Both have been widely studied and pharmacologically targeted for many years, without significant therapeutic results. In 2022, positive data on two monoclonal antibodies targeting Aβ, donanemab and lecanemab, followed by the 2023 FDA accelerated approval of lecanemab and the publication of the final results of the phase III Clarity AD study, have strengthened the hypothesis of a causal role of Aβ in the pathogenesis of AD. However, the magnitude of the clinical effect elicited by the two drugs is limited, suggesting that additional pathological mechanisms may contribute to the disease. Cumulative studies have shown inflammation as one of the main contributors to the pathogenesis of AD, leading to the recognition of a specific role of neuroinflammation synergic with the Aβ and NFTs cascades. The present review provides an overview of the investigational drugs targeting neuroinflammation that are currently in clinical trials. Moreover, their mechanisms of action, their positioning in the pathological cascade of events that occur in the brain throughout AD disease and their potential benefit/limitation in the therapeutic strategy in AD are discussed and highlighted as well. In addition, the latest patent requests for inflammation-targeting therapeutics to be developed in AD will also be discussed.
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Affiliation(s)
- Daniela Melchiorri
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Sara Merlo
- Department of Biomedical and Biotechnological Sciences, Section of Pharmacology, University of Catania, Catania, Italy
| | | | - John-Joseph Borg
- Malta Medicines Authority, San Ġwann, Malta
- School of Pharmacy, Department of Biology, University of Tor Vergata, Rome, Italy
| | - František Dráfi
- Institute of Experimental Pharmacology and Toxicology, Centre of Experimental Medicine SAS Bratislava, Bratislava, Slovakia
- State Institute for Drug Control, Bratislava, Slovakia
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23
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Manickam V, Gawande DY, Stothert AR, Clayman AC, Batalkina L, Warchol ME, Ohlemiller KK, Kaur T. Macrophages Promote Repair of Inner Hair Cell Ribbon Synapses following Noise-Induced Cochlear Synaptopathy. J Neurosci 2023; 43:2075-2089. [PMID: 36810227 PMCID: PMC10039750 DOI: 10.1523/jneurosci.1273-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 02/07/2023] [Accepted: 02/10/2023] [Indexed: 02/23/2023] Open
Abstract
Resident cochlear macrophages rapidly migrate into the inner hair cell synaptic region and directly contact the damaged synaptic connections after noise-induced synaptopathy. Eventually, such damaged synapses are spontaneously repaired, but the precise role of macrophages in synaptic degeneration and repair remains unknown. To address this, cochlear macrophages were eliminated using colony stimulating factor 1 receptor (CSF1R) inhibitor, PLX5622. Sustained treatment with PLX5622 in CX3CR1 GFP/+ mice of both sexes led to robust elimination of resident macrophages (∼94%) without significant adverse effects on peripheral leukocytes, cochlear function, and structure. At 1 day (d) post noise exposure of 93 or 90 dB SPL for 2 hours, the degree of hearing loss and synapse loss were comparable in the presence and absence of macrophages. At 30 d after exposure, damaged synapses appeared repaired in the presence of macrophages. However, in the absence of macrophages, such synaptic repair was significantly reduced. Remarkably, on cessation of PLX5622 treatment, macrophages repopulated the cochlea, leading to enhanced synaptic repair. Elevated auditory brainstem response thresholds and reduced auditory brainstem response Peak 1 amplitudes showed limited recovery in the absence of macrophages but recovered similarly with resident and repopulated macrophages. Cochlear neuron loss was augmented in the absence of macrophages but showed preservation with resident and repopulated macrophages after noise exposure. While the central auditory effects of PLX5622 treatment and microglia depletion remain to be investigated, these data demonstrate that macrophages do not affect synaptic degeneration but are necessary and sufficient to restore cochlear synapses and function after noise-induced synaptopathy.SIGNIFICANCE STATEMENT The synaptic connections between cochlear inner hair cells and spiral ganglion neurons can be lost because of noise over exposure or biological aging. This loss may represent the most common causes of sensorineural hearing loss also known as hidden hearing loss. Synaptic loss results in degradation of auditory information, leading to difficulty in listening in noisy environments and other auditory perceptual disorders. We demonstrate that resident macrophages of the cochlea are necessary and sufficient to restore synapses and function following synaptopathic noise exposure. Our work reveals a novel role for innate-immune cells, such as macrophages in synaptic repair, that could be harnessed to regenerate lost ribbon synapses in noise- or age-linked cochlear synaptopathy, hidden hearing loss, and associated perceptual anomalies.
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Affiliation(s)
- Vijayprakash Manickam
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
| | - Dinesh Y Gawande
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
| | - Andrew R Stothert
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
| | - Anna C Clayman
- Department of Otolaryngology, School of Medicine, Washington University, St. Louis, Missouri 63110
| | - Lyudmila Batalkina
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
| | - Mark E Warchol
- Department of Otolaryngology, School of Medicine, Washington University, St. Louis, Missouri 63110
| | - Kevin K Ohlemiller
- Department of Otolaryngology, School of Medicine, Washington University, St. Louis, Missouri 63110
| | - Tejbeer Kaur
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
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24
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The Chemokine Receptor CCR1 Mediates Microglia Stimulated Glioma Invasion. Int J Mol Sci 2023; 24:ijms24065136. [PMID: 36982211 PMCID: PMC10049042 DOI: 10.3390/ijms24065136] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 02/22/2023] [Accepted: 03/02/2023] [Indexed: 03/10/2023] Open
Abstract
Glioblastoma multiforme (GBM) is the most aggressive form of adult brain tumor which is highly resistant to conventional treatment and therapy. Glioma cells are highly motile resulting in infiltrative tumors with poorly defined borders. Another hallmark of GBM is a high degree of tumor macrophage/microglia infiltration. The level of these tumor-associated macrophages/microglia (TAMs) correlates with higher malignancy and poorer prognosis. We previously demonstrated that inhibition of TAM infiltration into glioma tumors with the CSF-1R antagonist pexidartinib (PLX3397) can inhibit glioma cell invasion in-vitro and in-vivo. In this study, we demonstrate an important role for the chemokine receptor CCR1 in mediating microglia/TAM stimulated glioma invasion. Using two structurally distinct CCR1 antagonists, including a novel inhibitor “MG-1-5”, we were able to block microglial activated GL261 glioma cell invasion in a dose dependent manner. Interestingly, treatment of a murine microglia cell line with glioma conditioned media resulted in a strong induction of CCR1 gene and protein expression. This induction was attenuated by inhibition of CSF-1R. In addition, glioma conditioned media treatment of microglia resulted in a rapid upregulation of gene expression of several CCR1 ligands including CCL3, CCL5, CCL6 and CCL9. These data support the existence of tumor stimulated autocrine loop within TAMs which ultimately mediates tumor cell invasion.
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25
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Pereira CPM, Francis-Oliveira J, Singulani MP, Ferreira AFF, Britto LRG. Microglial depletion exacerbates motor impairment and dopaminergic neuron loss in a 6-OHDA model of Parkinson's disease. J Neuroimmunol 2023; 375:578019. [PMID: 36681049 DOI: 10.1016/j.jneuroim.2023.578019] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/28/2022] [Accepted: 01/11/2023] [Indexed: 01/15/2023]
Abstract
6-hydroxydopamine (6-OHDA) is a common neurotoxin used to induce Parkinson's disease (PD) in mice, exerting neurotoxic effects through the production of reactive oxygen species and microglial activation. However, the role of microglia in PD is still not clear, with contradictory reports showing neuroprotection or exacerbation of neuronal death. Microglial depletion aggravates motor coordination impairments and reduces tyrosine hydroxylase positive neurons in the substantia nigra pars compacta. Moreover, MeCP2 and Adora1 genes expression were downregulated, suggesting they may be involved in the neurodegenerative process. This study highlights that microglia plays a protective role in dopaminergic neuron survival during the initial phase of PD, and the investigation of the mechanisms of this effect in future studies will help elucidate the pathophysiology of PD.
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Affiliation(s)
- Carolina Parga Martins Pereira
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil; Department of Neurobiology and Behavior, Institute of Memory Impairments and Neurological Disorders, University of California, Irvine, USA.
| | - José Francis-Oliveira
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil; Departament of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, USA
| | - Monique Patricio Singulani
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil
| | - Ana Flávia Fernandes Ferreira
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil
| | - Luiz Roberto G Britto
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil
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26
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CSF1R inhibitors induce a sex-specific resilient microglial phenotype and functional rescue in a tauopathy mouse model. Nat Commun 2023; 14:118. [PMID: 36624100 PMCID: PMC9829908 DOI: 10.1038/s41467-022-35753-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 12/23/2022] [Indexed: 01/10/2023] Open
Abstract
Microglia are central to pathogenesis in many neurological conditions. Drugs targeting colony-stimulating factor-1 receptor (CSF1R) to block microglial proliferation in preclinical disease models have shown mixed outcomes, thus the therapeutic potential of this approach remains unclear. Here, we show that CSF1R inhibitors given by multiple dosing paradigms in the Tg2541 tauopathy mouse model cause a sex-independent reduction in pathogenic tau and reversion of non-microglial gene expression patterns toward a normal wild type signature. Despite greater drug exposure in male mice, only female mice have functional rescue and extended survival. A dose-dependent upregulation of immediate early genes and neurotransmitter dysregulation are observed in the brains of male mice only, indicating that excitotoxicity may preclude functional benefits. Drug-resilient microglia in male mice exhibit morphological and gene expression patterns consistent with increased neuroinflammatory signaling, suggesting a mechanistic basis for sex-specific excitotoxicity. Complete microglial ablation is neither required nor desirable for neuroprotection and therapeutics targeting microglia must consider sex-dependent effects.
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27
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Torres-Rodriguez O, Ortiz-Nazario E, Rivera-Escobales Y, Velazquez B, Colón M, Porter JT. Sex-dependent effects of microglial reduction on impaired fear extinction induced by single prolonged stress. Front Behav Neurosci 2023; 16:1014767. [PMID: 36699653 PMCID: PMC9868263 DOI: 10.3389/fnbeh.2022.1014767] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 12/12/2022] [Indexed: 01/11/2023] Open
Abstract
Single prolonged stress (SPS) is a preclinical rodent model for studying post-traumatic stress disorder (PTSD)-like behaviors. Previously we found that increased expression of the microglial marker Iba-1 in the ventral hippocampus after SPS exposure was associated with impaired fear extinction, suggesting that microglial activity contributed to the SPS-induced behavioral changes. To test this, we examined whether reducing microglia with the colony-stimulating factor 1 receptor blocker, PLX3397, in the diet would prevent the SPS-induced extinction impairment. Male rats exposed to SPS showed enhanced fear acquisition and impaired fear extinction memory. Adding PLX3397 to the diet prevented these behavioral changes. In contrast, PLX3397 did not prevent SPS from impairing fear extinction memory in the female rats. Despite the sex-dependent behavioral effects, we found a reduced number and area fraction of Iba-1+ microglia in both male and female rats suggesting that PLX3397 had similar effects on microglia in both sexes. Altogether, these results suggest that microglia contribute to the behavioral changes induced by SPS in male but not female rats.
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Affiliation(s)
- Orlando Torres-Rodriguez
- Department of Basic Sciences, Ponce Research Institute, Ponce Health Sciences University, Ponce, Puerto Rico
| | - Emily Ortiz-Nazario
- Department of Biomedical Sciences, Pontifical Catholic University of Puerto Rico, Ponce, Puerto Rico
| | - Yesenia Rivera-Escobales
- Department of Basic Sciences, Ponce Research Institute, Ponce Health Sciences University, Ponce, Puerto Rico
| | - Bethzaly Velazquez
- Department of Basic Sciences, Ponce Research Institute, Ponce Health Sciences University, Ponce, Puerto Rico
| | - María Colón
- Department of Basic Sciences, Ponce Research Institute, Ponce Health Sciences University, Ponce, Puerto Rico
| | - James T. Porter
- Department of Basic Sciences, Ponce Research Institute, Ponce Health Sciences University, Ponce, Puerto Rico
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28
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Picard K, Corsi G, Decoeur F, Di Castro MA, Bordeleau M, Persillet M, Layé S, Limatola C, Tremblay MÈ, Nadjar A. Microglial homeostasis disruption modulates non-rapid eye movement sleep duration and neuronal activity in adult female mice. Brain Behav Immun 2023; 107:153-164. [PMID: 36202169 DOI: 10.1016/j.bbi.2022.09.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 09/12/2022] [Accepted: 09/30/2022] [Indexed: 11/07/2022] Open
Abstract
Sleep is a natural physiological state, tightly regulated through several neuroanatomical and neurochemical systems, which is essential to maintain physical and mental health. Recent studies revealed that the functions of microglia, the resident immune cells of the brain, differ along the sleep-wake cycle. Inflammatory cytokines, such as interleukin-1β and tumor necrosis factor-α, mainly produced by microglia in the brain, are also well-known to promote sleep. However, the contributing role of microglia on sleep regulation remains largely elusive, even more so in females. Given the higher prevalence of various sleep disorders in women, we aimed to determine the role of microglia in regulating the sleep-wake cycle specifically in female mice. Microglia were depleted in adult female mice with inhibitors of the colony-stimulating factor 1 receptor (CSF1R) (PLX3397 or PLX5622), which is required for microglial population maintenance. This led to a 65-73% reduction of the microglial population, as confirmed by immunofluorescence staining against IBA1 (marker of microglia/macrophages) and TMEM119 (microglia-specific marker) in the reticular nucleus of the thalamus and primary motor cortex. The spontaneous sleep-wake cycle was evaluated at steady-state, during microglial homeostasis disruption and after complete microglial repopulation, upon cessation of treatment with the inhibitors of CSF1R, using electroencephalography (EEG) and electromyography (EMG). We found that microglia-depleted female mice spent more time in non-rapid eye movement (NREM) sleep and had an increased number of NREM sleep episodes, which was partially restored after microglial total repopulation. To determine whether microglia could regulate sleep locally by modulating synaptic transmission, we used patch clamp to record spontaneous activity of pyramidal neurons in the primary motor cortex, which showed an increase of excitatory synaptic transmission during the dark phase. These changes in neuronal activity were modulated by microglial depletion in a phase-dependent manner. Altogether, our results indicate that microglia are involved in the sleep regulation of female mice, further strengthening their potential implication in the development and/or progression of sleep disorders. Furthermore, our findings indicate that microglial repopulation can contribute to normalizing sleep alterations caused by their partial depletion.
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Affiliation(s)
- Katherine Picard
- Axe Neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Département de médecine moléculaire, Université Laval, Québec, QC, Canada; Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Giorgio Corsi
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Fanny Decoeur
- Université de Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000 Bordeaux, France
| | | | - Maude Bordeleau
- Axe Neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada
| | - Marine Persillet
- Université de Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000 Bordeaux, France
| | - Sophie Layé
- Université de Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000 Bordeaux, France
| | - Cristina Limatola
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy; Department of Neurophysiology, Neuropharmacology, Inflammaging, IRCCS Neuromed, Pozzilli, Italy
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada; Département de médecine moléculaire, Université Laval, Québec, QC, Canada; Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada; Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
| | - Agnès Nadjar
- Université de Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000 Bordeaux, France; INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U1215, F-33000 Bordeaux, France; Institut Universitaire de France (IUF), France.
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29
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El Jordi O, Fischer KD, Meyer TB, Atwood BK, Oblak AL, Pan RW, McKinzie DL. Microglial knockdown does not affect acute withdrawal but delays analgesic tolerance from oxycodone in male and female C57BL/6J mice. ADVANCES IN DRUG AND ALCOHOL RESEARCH 2022; 2:10848. [PMID: 38390615 PMCID: PMC10880796 DOI: 10.3389/adar.2022.10848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 12/05/2022] [Indexed: 02/24/2024]
Abstract
Opioid Use Disorder (OUD) affects approximately 8%-12% of the population. In dependent individuals, abrupt cessation of opioid taking results in adverse withdrawal symptoms that reinforce drug taking behavior. Considerable unmet clinical need exists for new pharmacotherapies to treat opioid withdrawal as well as improve long-term abstinence. The neuroimmune system has received much scientific attention in recent years as a potential therapeutic target to combat various neurodegenerative and psychiatric disorders including addiction. However, the specific contribution of microglia has not been investigated in oxycodone dependence. Chronic daily treatment with the CSF1R inhibitor Pexidartinib (PLX3397) was administered to knockdown microglia expression and evaluate consequences on analgesia and on naloxone induced withdrawal from oxycodone. In vivo results indicated that an approximately 40% reduction in brain IBA1 staining was achieved in the PLX treatment group, which was associated with a delay in the development of analgesic tolerance to oxycodone and maintained antinociceptive efficacy. Acute withdrawal behavioral symptoms, brain astrocyte expression, and levels of many neuroinflammatory markers were not affected by PLX treatment. KC/GRO (also known as CXCL1) was significantly enhanced in the somatosensory cortex in oxycodone-treated mice receiving PLX. Microglial knock-down did not affect the expression of naloxoneinduced opioid withdrawal but affected antinociceptive responsivity. The consequences of increased KC/GRO expression within the somatosensory cortex due to microglial reduction during opioid dependence are unclear but may be important for neural pathways mediating opioid-induced analgesia.
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Affiliation(s)
- Omar El Jordi
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, United States
| | - Kathryn D Fischer
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, United States
| | - Timothy B Meyer
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, United States
| | - Brady K Atwood
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, United States
| | - Adrian L Oblak
- Department of Radiology and Imaging Sciences, Indiana University, Indianapolis, IN, United States
| | - Raymond W Pan
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, United States
| | - David L McKinzie
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, United States
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30
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Basilico B, Ferrucci L, Khan A, Di Angelantonio S, Ragozzino D, Reverte I. What microglia depletion approaches tell us about the role of microglia on synaptic function and behavior. Front Cell Neurosci 2022; 16:1022431. [PMID: 36406752 PMCID: PMC9673171 DOI: 10.3389/fncel.2022.1022431] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 10/17/2022] [Indexed: 11/06/2022] Open
Abstract
Microglia are dynamic cells, constantly surveying their surroundings and interacting with neurons and synapses. Indeed, a wealth of knowledge has revealed a critical role of microglia in modulating synaptic transmission and plasticity in the developing brain. In the past decade, novel pharmacological and genetic strategies have allowed the acute removal of microglia, opening the possibility to explore and understand the role of microglia also in the adult brain. In this review, we summarized and discussed the contribution of microglia depletion strategies to the current understanding of the role of microglia on synaptic function, learning and memory, and behavior both in physiological and pathological conditions. We first described the available microglia depletion methods highlighting their main strengths and weaknesses. We then reviewed the impact of microglia depletion on structural and functional synaptic plasticity. Next, we focused our analysis on the effects of microglia depletion on behavior, including general locomotor activity, sensory perception, motor function, sociability, learning and memory both in healthy animals and animal models of disease. Finally, we integrated the findings from the reviewed studies and discussed the emerging roles of microglia on the maintenance of synaptic function, learning, memory strength and forgetfulness, and the implications of microglia depletion in models of brain disease.
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Affiliation(s)
| | - Laura Ferrucci
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Azka Khan
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Silvia Di Angelantonio
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- Center for Life Nano- and Neuro-Science, Istituto Italiano di Tecnologia, Rome, Italy
| | - Davide Ragozzino
- Laboratory Affiliated to Institute Pasteur Italia – Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Rome, Italy
- *Correspondence: Davide Ragozzino,
| | - Ingrid Reverte
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Rome, Italy
- Ingrid Reverte,
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31
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Boucher T, Liang S, Brown AM. Advancing basic and translational research to deepen understanding of the molecular immune-mediated mechanisms regulating long-term persistence of HIV-1 in microglia in the adult human brain. J Leukoc Biol 2022; 112:1223-1231. [PMID: 35612272 PMCID: PMC9613482 DOI: 10.1002/jlb.1mr0422-620r] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 04/22/2022] [Indexed: 12/30/2022] Open
Abstract
Knowledge about the diversity microglia (MG) type and function in the rodent and human brain has advanced significantly in the last few years. Nevertheless, we have known for 40 years that MG, monocytes, and macrophages in the brain play crucial roles in the pathogenesis of the HIV-1 in all tissues. HIV enters and spreads in the brain early, long before the initiation of antiviral therapy. As a result, many people with HIV continue to experience neurologic and neuropsychiatric comorbid conditions collectively known as HIV-associated neurocognitive disorder (HAND). HIV pathogenic sequelae in the CNS pose a challenge for cure strategies. Detailed understanding at a mechanistic level of how low-level and latent HIV-1 infection in MG negatively impacts neuroglial function has remained somewhat elusive. Direct rigorous in vivo experimental validation that the virus can integrate into MG and assume a latent but reactivatable state has remained constrained. However, there is much excitement that human in vitro models for MG can now help close the gap. This review will provide a brief background to place the role of MG in the ongoing neurologic complications of HIV infection of the CNS, then focus on the use and refinement of human postmitotic monocyte-derived MG-like cells and how they are being applied to advance research on HIV persistence and proinflammatory signaling in the CNS. Critically, an understanding of myeloid plasticity and heterogeneity and rigorous attention to all aspects of cell handling is essential for reproducibility. Summary Sentence: This review focuses on human postmitotic monocyte-derived microglia-like cells as tools to advance research on HIV persistence and neuroinflammatory signaling.
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Affiliation(s)
- Thomas Boucher
- Department of NeurologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Shijun Liang
- Department of NeurologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Amanda M. Brown
- Department of NeurologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
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Green TRF, Murphy SM, Rowe RK. Comparisons of quantitative approaches for assessing microglial morphology reveal inconsistencies, ecological fallacy, and a need for standardization. Sci Rep 2022; 12:18196. [PMID: 36307475 PMCID: PMC9616881 DOI: 10.1038/s41598-022-23091-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 10/25/2022] [Indexed: 12/31/2022] Open
Abstract
Microglial morphology is used to measure neuroinflammation and pathology. For reliable inference, it is critical that microglial morphology is accurately quantified and that results can be easily interpreted and compared across studies and laboratories. The process through which microglial morphology is quantified is a key methodological choice and little is known about how this choice may bias conclusions. We applied five of the most commonly used ImageJ-based methods for quantifying the microglial morphological response to a stimulus to identical photomicrographs and individual microglial cells isolated from these photomicrographs, which allowed for direct comparisons of results generated using these approaches. We found a lack of comparability across methods that analyzed full photomicrographs, with significant discrepancies in results among the five methods. Quantitative methods to analyze microglial morphology should be selected based on several criteria, and combinations of these methods may give the most biologically accurate representation of microglial morphology.
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Affiliation(s)
- Tabitha R. F. Green
- grid.134563.60000 0001 2168 186XDepartment of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ USA ,grid.266190.a0000000096214564Department of Integrative Physiology, University of Colorado, 2860 Wilderness Place, Boulder, CO 80301 USA
| | - Sean M. Murphy
- grid.134563.60000 0001 2168 186XDepartment of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ USA
| | - Rachel K. Rowe
- grid.134563.60000 0001 2168 186XDepartment of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ USA ,grid.266190.a0000000096214564Department of Integrative Physiology, University of Colorado, 2860 Wilderness Place, Boulder, CO 80301 USA
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Race B, Williams K, Baune C, Striebel JF, Long D, Thomas T, Lubke L, Chesebro B, Carroll JA. Microglia have limited influence on early prion pathogenesis, clearance, or replication. PLoS One 2022; 17:e0276850. [PMID: 36301895 PMCID: PMC9612458 DOI: 10.1371/journal.pone.0276850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 10/14/2022] [Indexed: 11/07/2022] Open
Abstract
Microglia (MG) are critical to host defense during prion infection, but the mechanism(s) of this neuroprotection are poorly understood. To better examine the influence of MG during prion infection, we reduced MG in the brains of C57BL/10 mice using PLX5622 and assessed prion clearance and replication using multiple approaches that included bioassay, immunohistochemistry, and Real-Time Quaking Inducted Conversion (RT-QuIC). We also utilized a strategy of intermittent PLX5622 treatments to reduce MG and allow MG repopulation to test whether new MG could alter prion disease progress. Lastly, we investigated the influence of MG using tga20 mice, a rapid prion model that accumulates fewer pathological features and less PrPres in the infected brain. In C57BL/10 mice we found that MG were excluded from the inoculation site early after infection, but Iba1 positive infiltrating monocytes/macrophage were present. Reducing MG in the brain prior to prion inoculation did not increase susceptibility to prion infection. Short intermittent treatments with PLX5622 in prion infected C57BL/10 mice after 80 dpi were unsuccessful at altering the MG population, gliosis, or survival. Additionally, MG depletion using PLX5622 in tga20 mice had only a minor impact on prion pathogenesis, indicating that the presence of MG might be less important in this fast model with less prion accumulation. In contrast to the benefits of MG against prion disease in late stages of disease, our current experiments suggest MG do not play a role in early prion pathogenesis, clearance, or replication.
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Affiliation(s)
- Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail: (BR); (JAC)
| | - Katie Williams
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Chase Baune
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - James F. Striebel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Dan Long
- Rocky Mountain Veterinary Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Tina Thomas
- Rocky Mountain Veterinary Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Lori Lubke
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - James A. Carroll
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail: (BR); (JAC)
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Battis K, Florio JB, Mante M, Lana A, Naumann I, Gauer C, Lambrecht V, Müller SJ, Cobo I, Fixsen B, Kim HY, Masliah E, Glass CK, Schlachetzki JCM, Rissman RA, Winkler J, Hoffmann A. CSF1R-Mediated Myeloid Cell Depletion Prolongs Lifespan But Aggravates Distinct Motor Symptoms in a Model of Multiple System Atrophy. J Neurosci 2022; 42:7673-7688. [PMID: 36333098 PMCID: PMC9546481 DOI: 10.1523/jneurosci.0417-22.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 08/03/2022] [Accepted: 08/15/2022] [Indexed: 01/21/2023] Open
Abstract
As the CNS-resident macrophages and member of the myeloid lineage, microglia fulfill manifold functions important for brain development and homeostasis. In the context of neurodegenerative diseases, they have been implicated in degenerative and regenerative processes. The discovery of distinct activation patterns, including increased phagocytosis, indicated a damaging role of myeloid cells in multiple system atrophy (MSA), a devastating, rapidly progressing atypical parkinsonian disorder. Here, we analyzed the gene expression profile of microglia in a mouse model of MSA (MBP29-hα-syn) and identified a disease-associated expression profile and upregulation of the colony-stimulating factor 1 (Csf1). Thus, we hypothesized that CSF1 receptor-mediated depletion of myeloid cells using PLX5622 modifies the disease progression and neuropathological phenotype in this mouse model. Intriguingly, sex-balanced analysis of myeloid cell depletion in MBP29-hα-syn mice revealed a two-faced outcome comprising an improved survival rate accompanied by a delayed onset of neurological symptoms in contrast to severely impaired motor functions. Furthermore, PLX5622 reversed gene expression profiles related to myeloid cell activation but reduced gene expression associated with transsynaptic signaling and signal release. While transcriptional changes were accompanied by a reduction of dopaminergic neurons in the SNpc, striatal neuritic density was increased upon myeloid cell depletion in MBP29-hα-syn mice. Together, our findings provide insight into the complex, two-faced role of myeloid cells in the context of MSA emphasizing the importance to carefully balance the beneficial and adverse effects of CSF1R inhibition in different models of neurodegenerative disorders before its clinical translation.SIGNIFICANCE STATEMENT Myeloid cells have been implicated as detrimental in the disease pathogenesis of multiple system atrophy. However, long-term CSF1R-dependent depletion of these cells in a mouse model of multiple system atrophy demonstrates a two-faced effect involving an improved survival associated with a delayed onset of disease and reduced inflammation which was contrasted by severely impaired motor functions, synaptic signaling, and neuronal circuitries. Thus, this study unraveled a complex role of myeloid cells in multiple system atrophy, which indicates important functions beyond the previously described disease-associated, destructive phenotype and emphasized the need of further investigation to carefully and individually fine-tune immunologic processes in different neurodegenerative diseases.
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Affiliation(s)
- Kristina Battis
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
| | - Jazmin B Florio
- Department of Neurosciences, University of California-San Diego, La Jolla, California 92093
| | - Michael Mante
- Department of Neurosciences, University of California-San Diego, La Jolla, California 92093
| | - Addison Lana
- Department of Cellular and Molecular Medicine, University of California-San Diego, La Jolla, California 92093
| | - Isabel Naumann
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
| | - Carina Gauer
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
| | - Vera Lambrecht
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
- Center of Rare Diseases Erlangen (ZSEER), University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
| | - Simon Julian Müller
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
| | - Isidoro Cobo
- Department of Cellular and Molecular Medicine, University of California-San Diego, La Jolla, California 92093
| | - Bethany Fixsen
- Department of Cellular and Molecular Medicine, University of California-San Diego, La Jolla, California 92093
| | - Ha Yeon Kim
- Department of Neurosciences, University of California-San Diego, La Jolla, California 92093
| | - Eliezer Masliah
- Division of Neuroscience, National Institute on Aging, National Institutes of Health, Bethesda, Maryland 20892
| | - Christopher K Glass
- Department of Cellular and Molecular Medicine, University of California-San Diego, La Jolla, California 92093
| | - Johannes C M Schlachetzki
- Department of Cellular and Molecular Medicine, University of California-San Diego, La Jolla, California 92093
| | - Robert A Rissman
- Department of Neurosciences, University of California-San Diego, La Jolla, California 92093
| | - Jürgen Winkler
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
- Center of Rare Diseases Erlangen (ZSEER), University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
| | - Alana Hoffmann
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, 91054, Germany
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Liu H, Badawy M, Sun S, Cruz G, Ge S, Xiong Q. Microglial repopulation alleviates age-related decline of stable wakefulness in mice. Front Aging Neurosci 2022; 14:988166. [PMID: 36262885 PMCID: PMC9574185 DOI: 10.3389/fnagi.2022.988166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 09/06/2022] [Indexed: 12/04/2022] Open
Abstract
Changes in wake/sleep architecture have been observed in both aged human and animal models, presumably due to various functional decay throughout the aging body particularly in the brain. Microglia have emerged as a modulator for wake/sleep architecture in the adult brain, and displayed distinct morphology and activity in the aging brain. However, the link between microglia and age-related wake/sleep changes remains elusive. In this study, we systematically examined the brain vigilance and microglia morphology in aging mice (3, 6, 12, and 18 months old), and determined how microglia affect the aging-related wake/sleep alterations in mice. We found that from young adult to aged mice there was a clear decline in stable wakefulness at nighttime, and a decrease of microglial processes length in various brain regions involved in wake/sleep regulation. The decreased stable wakefulness can be restored following the time course of microglia depletion and repopulation in the adult brain. Microglia repopulation in the aging brain restored age-related decline in stable wakefulness. Taken together, our findings suggest a link between aged microglia and deteriorated stable wakefulness in aged brains.
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36
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Riquier AJ, Sollars SI. Terminal field volume of the glossopharyngeal nerve in adult rats reverts to prepruning size following microglia depletion with PLX5622. Dev Neurobiol 2022; 82:613-624. [PMID: 36308508 PMCID: PMC9790758 DOI: 10.1002/dneu.22904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 09/15/2022] [Accepted: 10/19/2022] [Indexed: 01/30/2023]
Abstract
Programmed reduction of synapses is a hallmark of the developing brain, with sensory systems emerging as useful models with which to study this pruning. The central projections (terminal field) of the gustatory glossopharyngeal nerve (GL) of the rat are a prime example of developmental pruning, undergoing an approximate 66% reduction in volume from postnatal day 15 (P15) to P25. Later in adulthood, developmental GL pruning can be experimentally reversed, expanding to preweaning volumes, suggesting mature volumes may be actively maintained throughout the life span. Microglia are central nervous system glia cells that perform pruning and maintenance functions in other sensory systems, including other gustatory nerves. To determine their role in GL pruning, we depleted microglia from Sprague-Dawley rat brains from P1 to P40 using daily intraperitoneal injections of the colony-stimulating factor 1 receptor inhibitor PLX5622. This prevented GL developmental pruning, resulting in preweaning terminal field volumes and innervation patterns persisting through P40, 2 weeks after pruning is normally completed. These findings show microglia are necessary for developmental GL pruning. Ceasing PLX5622 treatments at P40 allowed microglia repopulation, and within 4 weeks the GL terminal field had reduced to control volumes, indicating that pruning can occur outside of the typical developmental period. Conversely, when microglia were depleted in adult rats, GL terminal fields expanded, reverting to sizes comparable to the neonatal rat. These data indicate that microglia are required for GL pruning and may continue to maintain the GL terminal field at a reduced size into adulthood.
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Affiliation(s)
- Andrew J. Riquier
- Department of PsychologyUniversity of Nebraska at OmahaOmahaNebraskaUSA
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Barca C, Kiliaan AJ, Wachsmuth L, Foray C, Hermann S, Faber C, Schäfers M, Wiesmann M, Zinnhardt B, Jacobs AH. Short-Term Colony-Stimulating Factor 1 Receptor Inhibition-Induced Repopulation After Stroke Assessed by Longitudinal 18F-DPA-714 PET Imaging. J Nucl Med 2022; 63:1408-1414. [PMID: 35115368 PMCID: PMC9454465 DOI: 10.2967/jnumed.121.263004] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 01/12/2022] [Indexed: 01/26/2023] Open
Abstract
Studies on colony-stimulating factor 1 receptor (CSF-1R) inhibition-induced microglia depletion indicated that inhibitor withdrawal allowed the renewal of the microglia compartment via repopulation and resolved the inflammatory imbalance. Therefore, we investigated for the first time (to our knowledge) the effects of microglia repopulation on inflammation and functional outcomes in an ischemic mouse model using translocator protein (TSPO)-PET/CT and MR imaging, ex vivo characterization, and behavioral tests. Methods: Eight C57BL/6 mice per group underwent a 30-min transient occlusion of the middle cerebral artery. The treatment group received CSF-1R inhibitor in 1,200 ppm PLX5622 chow (Plexxikon Inc.) from days 3 to 7 to induce microglia/macrophage depletion and then went back to a control diet to allow repopulation. The mice underwent T2-weighted MRI on day 1 after ischemia and 18F-labeled N,N-diethyl-2-(2-[4-(2-fluoroethoxy)phenyl]-5,7-dimethylpyrazolo[1,5-α]pyrimidine-3-yl)acetamide (18F-DPA-714) (TSPO) PET/CT on days 7, 14, 21, and 30. The percentage injected tracer dose per milliliter within the infarct, contralateral striatum, and spleen was assessed. Behavioral tests were performed to assess motor function recovery. Brains were harvested on days 14 and 35 after ischemia for ex vivo analyses (immunoreactivity and real-time quantitative polymerase chain reaction) of microglia- and macrophage-related markers. Results: Repopulation significantly increased 18F-DPA-714 uptake within the infarct on days 14 (P < 0.001) and 21 (P = 0.002) after ischemia. On day 14, the ionized calcium binding adaptor molecule 1 (Iba-1)-positive cell population showed significantly higher expression of TSPO, CSF-1R, and CD68, in line with microglia repopulation. Gene expression analyses on day 14 indicated a significant increase in microglia-related markers (csf-1r, aif1, and p2ry12) with repopulation, whereas peripheral cell recruitment-related gene expression decreased (cx3cr1 and ccr2), indicative of peripheral recruitment during CSF-1R inhibition. Similarly, uncorrected spleen uptake was significantly higher on day 7 after ischemia with treatment (P = 0.001) and decreased after drug withdrawal. PLX5622-treated mice walked a longer distance (P < 0.001) and more quickly (P = 0.009), and showed greater forelimb strength (P < 0.001), than control mice on day 14. Conclusion: This study highlighted the potential of 18F-DPA-714 PET/CT imaging to track microglia and macrophage repopulation after short-term CSF-1R inhibition in stroke.
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Affiliation(s)
- Cristina Barca
- European Institute for Molecular Imaging, University of Münster, Münster, Germany;
| | - Amanda J. Kiliaan
- Department of Medical Imaging/Anatomy, Radboud University Medical Center, Radboud, The Netherlands
| | - Lydia Wachsmuth
- Translational Research Imaging Center, University Hospital Münster, Münster, Germany
| | - Claudia Foray
- European Institute for Molecular Imaging, University of Münster, Münster, Germany
| | - Sven Hermann
- European Institute for Molecular Imaging, University of Münster, Münster, Germany
| | - Cornelius Faber
- Translational Research Imaging Center, University Hospital Münster, Münster, Germany
| | - Michael Schäfers
- European Institute for Molecular Imaging, University of Münster, Münster, Germany;,Department of Nuclear Medicine, University Hospital Münster, Münster, Germany
| | - Maximilian Wiesmann
- Department of Medical Imaging/Anatomy, Radboud University Medical Center, Radboud, The Netherlands
| | - Bastian Zinnhardt
- European Institute for Molecular Imaging, University of Münster, Münster, Germany;,Department of Nuclear Medicine, University Hospital Münster, Münster, Germany;,Biomarkers and Translational Technologies, Pharma Research and Early Development, F. Hoffmann-La Roche Ltd., Basel, Switzerland; and
| | - Andreas H. Jacobs
- European Institute for Molecular Imaging, University of Münster, Münster, Germany;,Department of Geriatrics and Neurology, Johanniter Hospital, Bonn, Germany
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38
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Rowe RK, Green TRF, Giordano KR, Ortiz JB, Murphy SM, Opp MR. Microglia Are Necessary to Regulate Sleep after an Immune Challenge. BIOLOGY 2022; 11:1241. [PMID: 36009868 PMCID: PMC9405260 DOI: 10.3390/biology11081241] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 07/29/2022] [Accepted: 08/17/2022] [Indexed: 12/31/2022]
Abstract
Microglia play a critical role in the neuroimmune response, but little is known about the role of microglia in sleep following an inflammatory trigger. Nevertheless, decades of research have been predicated on the assumption that an inflammatory trigger increases sleep through microglial activation. We hypothesized that mice (n = 30) with depleted microglia using PLX5622 (PLX) would sleep less following the administration of lipopolysaccharide (LPS) to induce inflammation. Brains were collected and microglial morphology was assessed using quantitative skeletal analyses and physiological parameters were recorded using non-invasive piezoelectric cages. Mice fed PLX diet had a transient increase in sleep that dissipated by week 2. Subsequently, following a first LPS injection (0.4 mg/kg), mice with depleted microglia slept more than mice on the control diet. All mice were returned to normal rodent chow to repopulate microglia in the PLX group (10 days). Nominal differences in sleep existed during the microglia repopulation period. However, following a second LPS injection, mice with repopulated microglia slept similarly to control mice during the dark period but with longer bouts during the light period. Comparing sleep after the first LPS injection to sleep after the second LPS injection, controls exhibited temporal changes in sleep patterns but no change in cumulative minutes slept, whereas cumulative sleep in mice with repopulated microglia decreased during the dark period across all days. Repopulated microglia had a reactive morphology. We conclude that microglia are necessary to regulate sleep after an immune challenge.
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Affiliation(s)
- Rachel K. Rowe
- Department of Integrative Physiology, University of Colorado, Boulder, CO 80301, USA
- Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, USA
| | - Tabitha R. F. Green
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, USA
| | - Katherine R. Giordano
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, USA
- Phoenix Veterans Affairs Health Care System, Phoenix, AZ 85012, USA
| | - J. Bryce Ortiz
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, USA
- Phoenix Veterans Affairs Health Care System, Phoenix, AZ 85012, USA
| | - Sean M. Murphy
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, USA
| | - Mark R. Opp
- Department of Integrative Physiology, University of Colorado, Boulder, CO 80301, USA
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Liu Q, Huang Y, Duan M, Yang Q, Ren B, Tang F. Microglia as Therapeutic Target for Radiation-Induced Brain Injury. Int J Mol Sci 2022; 23:8286. [PMID: 35955439 PMCID: PMC9368164 DOI: 10.3390/ijms23158286] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 12/10/2022] Open
Abstract
Radiation-induced brain injury (RIBI) after radiotherapy has become an increasingly important factor affecting the prognosis of patients with head and neck tumor. With the delivery of high doses of radiation to brain tissue, microglia rapidly transit to a pro-inflammatory phenotype, upregulate phagocytic machinery, and reduce the release of neurotrophic factors. Persistently activated microglia mediate the progression of chronic neuroinflammation, which may inhibit brain neurogenesis leading to the occurrence of neurocognitive disorders at the advanced stage of RIBI. Fully understanding the microglial pathophysiology and cellular and molecular mechanisms after irradiation may facilitate the development of novel therapy by targeting microglia to prevent RIBI and subsequent neurological and neuropsychiatric disorders.
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Affiliation(s)
- Qun Liu
- The School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou 434023, China; (Q.L.); (Y.H.)
| | - Yan Huang
- The School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou 434023, China; (Q.L.); (Y.H.)
| | - Mengyun Duan
- Department of Pharmacology, School of Medicine, Yangtze University, Jingzhou 434023, China; (M.D.); (Q.Y.)
| | - Qun Yang
- Department of Pharmacology, School of Medicine, Yangtze University, Jingzhou 434023, China; (M.D.); (Q.Y.)
| | - Boxu Ren
- The School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou 434023, China; (Q.L.); (Y.H.)
| | - Fengru Tang
- Radiation Physiology Laboratory, Singapore Nuclear Research and Safety Initiative, National University of Singapore, Singapore 138602, Singapore
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40
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Shi W, Zhang J, Shang Z, Zhang Y, Xia Y, Fu H, Yu T. Restorative therapy using microglial depletion and repopulation for central nervous system injuries and diseases. Front Immunol 2022; 13:969127. [PMID: 35911768 PMCID: PMC9329909 DOI: 10.3389/fimmu.2022.969127] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 06/27/2022] [Indexed: 12/02/2022] Open
Abstract
Microglia are important resident immune cells in the central nervous system (CNS) and play an important role in its development, homeostasis, and disease treatments. Activated microglia perform diverse functions in mouse models of CNS neurodegenerative diseases or deficits. In humans, microglia have been linked to various neurodegenerative diseases. Following brain or spinal cord injury, microglia express pro- and anti-inflammatory phenotypes at different stages of recovery. With the development of pharmacological and genetic tools for microglial depletion, studies have demonstrated that microglial depletion exerts both positive and negative effects in the treatment of CNS diseases. Notably, microglial depletion provides an empty niche that stimulates production of new microglia. Microglial depletion and repopulation can not only treat diseases by eliminating dysfunctional microglia but can also provide an indication of the molecular mechanisms of diseases. Although this approach has shown impressive results, its use is still in its infancy. In this review, we summarize the current pharmacological and genetic tools for microglial depletion and highlight recent advances in microglial repopulation therapy for the treatment and functional recovery of neurological diseases and deficits. Finally, we briefly discuss the therapeutic challenges and prospective uses of microglial repopulation therapy.
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Affiliation(s)
- Weipeng Shi
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
- Medical Department of Qingdao University, Qingdao, China
| | - Jing Zhang
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
- Medical Department of Qingdao University, Qingdao, China
| | - Zhen Shang
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
- Medical Department of Qingdao University, Qingdao, China
| | - Yingze Zhang
- Key Laboratory of Biomechanics of Hebei Province, Department of Trauma Emergency Center, The Third Hospital of Hebei Medical University, Orthopaedics Research Institution of Hebei Province, Shijiazhuang, China
| | - Yanzhi Xia
- State Key Laboratory of Bio-Fibers and Eco-Textiles, Collaborative Innovation Center for Marine Biomass Fibers, Materials and Textiles of Shandong Province, College of Materials Science and Engineering, Institute of Marine Biobased Materials, Qingdao University, Qingdao, China
| | - Haitao Fu
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
- *Correspondence: Haitao Fu, ; Tengbo Yu,
| | - Tengbo Yu
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
- *Correspondence: Haitao Fu, ; Tengbo Yu,
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Ogaki A, Ikegaya Y, Koyama R. Replacement of Mouse Microglia With Human Induced Pluripotent Stem Cell (hiPSC)-Derived Microglia in Mouse Organotypic Slice Cultures. Front Cell Neurosci 2022; 16:918442. [PMID: 35910250 PMCID: PMC9325970 DOI: 10.3389/fncel.2022.918442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 06/20/2022] [Indexed: 11/24/2022] Open
Abstract
Microglia, the major immune cells in the brain, are reported to differ in gene expression patterns among species. Therefore, it would be preferable in some cases to use human microglia rather than mouse microglia in microglia-targeted disease research. In the past half a decade, researchers have developed in vivo transplantation methods in which human induced pluripotent stem cell-derived microglia (hiPSC-MG) are transplanted into a living mouse brain. However, in vivo transplantation methods are not necessarily accessible to all researchers due to the difficulty of obtaining the materials needed and the transplantation technique itself. In addition, for in vivo systems for microglia-targeted drug screening, it is difficult to control the pharmacokinetics, especially blood-brain barrier permeability. Therefore, in addition to existing in vivo transplantation systems, the development of an ex vivo transplantation system would help to further evaluate the properties of hiPSC-MG. In this study, we aimed to establish a method to efficiently transplant hiPSC-MG into cultured mouse hippocampal slices. We found that approximately 80% of the total microglia in a cultured slice were replaced by hiPSC-derived microglia when innate microglia were pharmacologically removed prior to transplantation. Furthermore, when neuronal death was induced by applying Kainic acid (KA) to slice cultures, transplanted hiPSC-MG changed their morphology and phagocytosed cell debris. Thus, this study provides a method to transplant hiPSC-MG into the mouse hippocampal slice cultures with a high replacement rate. Because the transplanted microglia survived and exerted phagocytic functions, this method will be useful for evaluating the properties of hiPSC-MG ex vivo.
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Affiliation(s)
- Ari Ogaki
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Bunkyo, Japan
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita, Japan
| | - Ryuta Koyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Bunkyo, Japan
- *Correspondence: Ryuta Koyama
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42
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Microglial Depletion Has No Impact on Disease Progression in a Mouse Model of Machado–Joseph Disease. Cells 2022; 11:cells11132022. [PMID: 35805106 PMCID: PMC9266279 DOI: 10.3390/cells11132022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/18/2022] [Accepted: 06/21/2022] [Indexed: 02/01/2023] Open
Abstract
Machado–Joseph disease (MJD), also known as spinocerebellar ataxia type 3 (SCA3), is an autosomal dominant neurodegenerative disorder (ND). While most research in NDs has been following a neuron-centric point of view, microglia are now recognized as crucial in the brain. Previous work revealed alterations that point to an increased activation state of microglia in the brain of CMVMJD135 mice, a MJD mouse model that replicates the motor symptoms and neuropathology of the human condition. Here, we investigated the extent to which microglia are actively contributing to MJD pathogenesis and symptom progression. For this, we used PLX3397 to reduce the number of microglia in the brain of CMVMJD135 mice. In addition, a set of statistical and machine learning models were further implemented to analyze the impact of PLX3397 on the morphology of the surviving microglia. Then, a battery of behavioral tests was used to evaluate the impact of microglial depletion on the motor phenotype of CMVMJD135 mice. Although PLX3397 treatment substantially reduced microglia density in the affected brain regions, it did not affect the motor deficits seen in CMVMJD135 mice. In addition to reducing the number of microglia, the treatment with PLX3397 induced morphological changes suggestive of activation in the surviving microglia, the microglia of wild-type animals becoming similar to those of CMVMJD135 animals. These results suggest that microglial cells are not key contributors for MJD progression. Furthermore, the impact of PLX3397 on microglial activation should be taken into account in the interpretation of findings of ND modification seen upon treatment with this CSF1R inhibitor.
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43
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Bray CE, Witcher KG, Adekunle-Adegbite D, Ouvina M, Witzel M, Hans E, Tapp ZM, Packer J, Goodman E, Zhao F, Chunchai T, O'Neil S, Chattipakorn SC, Sheridan J, Kokiko-Cochran ON, Askwith C, Godbout JP. Chronic Cortical Inflammation, Cognitive Impairment, and Immune Reactivity Associated with Diffuse Brain Injury Are Ameliorated by Forced Turnover of Microglia. J Neurosci 2022; 42:4215-4228. [PMID: 35440489 PMCID: PMC9121837 DOI: 10.1523/jneurosci.1910-21.2022] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 03/04/2022] [Accepted: 03/07/2022] [Indexed: 02/08/2023] Open
Abstract
Traumatic brain injury (TBI) is associated with an increased risk of cognitive, psychiatric, and neurodegenerative complications that may develop after injury. Increased microglial reactivity following TBI may underlie chronic neuroinflammation, neuropathology, and exaggerated responses to immune challenges. Therefore, the goal of this study was to force turnover of trauma-associated microglia that develop after diffuse TBI and determine whether this alleviated chronic inflammation, improved functional recovery and attenuated reduced immune reactivity to lipopolysaccharide (LPS) challenge. Male mice received a midline fluid percussion injury (mFPI) and 7 d later were subjected to a forced microglia turnover paradigm using CSF1R antagonism (PLX5622). At 30 d postinjury (dpi), cortical gene expression, dendritic complexity, myelin content, neuronal connectivity, cognition, and immune reactivity were assessed. Myriad neuropathology-related genes were increased 30 dpi in the cortex, and 90% of these gene changes were reversed by microglial turnover. Reduced neuronal connectivity was evident 30 dpi and these deficits were attenuated by microglial turnover. TBI-associated dendritic remodeling and myelin alterations, however, remained 30 dpi independent of microglial turnover. In assessments of functional recovery, increased depressive-like behavior, and cognitive impairment 30 dpi were ameliorated by microglia turnover. To investigate microglial priming and reactivity 30 dpi, mice were injected intraperitoneally with LPS. This immune challenge caused prolonged lethargy, sickness behavior, and microglial reactivity in the TBI mice. These extended complications with LPS in TBI mice were prevented by microglia turnover. Collectively, microglial turnover 7 dpi alleviated behavioral and cognitive impairments associated with microglial priming and immune reactivity 30 dpi.SIGNIFICANCE STATEMENT A striking feature of traumatic brain injury (TBI), even mild injuries, is that over 70% of individuals have long-term neuropsychiatric complications. Chronic inflammatory processes are implicated in the pathology of these complications and these issues can be exaggerated by immune challenge. Therefore, our goal was to force the turnover of microglia 7 d after TBI. This subacute 7 d postinjury (dpi) time point is a critical transitional period in the shift toward chronic inflammatory processes and microglia priming. This forced microglia turnover intervention in mice attenuated the deficits in behavior and cognition 30 dpi. Moreover, microglia priming and immune reactivity after TBI were also reduced with microglia turnover. Therefore, microglia represent therapeutic targets after TBI to reduce persistent neuroinflammation and improve recovery.
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Affiliation(s)
- Chelsea E Bray
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Kristina G Witcher
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | | | - Michelle Ouvina
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Mollie Witzel
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Emma Hans
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Zoe M Tapp
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Jonathan Packer
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Ethan Goodman
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Fangli Zhao
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
| | - Titikorn Chunchai
- Neurophysiology unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Shane O'Neil
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Siriporn C Chattipakorn
- Neurophysiology unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - John Sheridan
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Olga N Kokiko-Cochran
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
- Chronic Brain Injury Program, The Ohio State University, Columbus, Ohio 43210
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
| | - Candice Askwith
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
| | - Jonathan P Godbout
- Department of Neuroscience, The Ohio State University, Columbus, Ohio 43210
- Chronic Brain Injury Program, The Ohio State University, Columbus, Ohio 43210
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, Ohio 43210
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44
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Van Zeller M, Sebastião AM, Valente CA. Microglia Depletion from Primary Glial Cultures Enables to Accurately Address the Immune Response of Astrocytes. Biomolecules 2022; 12:biom12050666. [PMID: 35625594 PMCID: PMC9138960 DOI: 10.3390/biom12050666] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/25/2022] [Accepted: 04/28/2022] [Indexed: 02/01/2023] Open
Abstract
Astrocytes are the most abundant cells in the CNS parenchyma and play an essential role in several brain functions, such as the fine-tuning of synaptic transmission, glutamate uptake and the modulation of immune responses, among others. Much of the knowledge on the biology of astrocytes has come from the study of rodent primary astrocytic cultures. Usually, the culture is a mixed population of astrocytes and a small proportion of microglia. However, it is critical to have a pure culture of astrocytes if one wants to address their inflammatory response. If present, microglia sense the stimulus, rapidly proliferate and react to it, making it unfeasible to assess the individual responsiveness of astrocytes. Microglia have been efficiently eliminated in vivo through PLX-3397, a colony-stimulating factor-1 receptor (CSF-1R) inhibitor. In this work, the effectiveness of PLX-3397 in eradicating microglia from primary mixed glial cultures was evaluated. We tested three concentrations of PLX-3397—0.2 μM, 1 μM and 5 μM—and addressed its impact on the culture yield and viability of astrocytes. PLX-3397 is highly efficient in eliminating microglia without affecting the viability or response of cultured astrocytes. Thus, these highly enriched monolayers of astrocytes allow for the more accurate study of their immune response in disease conditions.
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Affiliation(s)
- Mariana Van Zeller
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, 1648-028 Lisboa, Portugal; (M.V.Z.); (A.M.S.)
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1648-028 Lisboa, Portugal
| | - Ana M. Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, 1648-028 Lisboa, Portugal; (M.V.Z.); (A.M.S.)
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1648-028 Lisboa, Portugal
| | - Cláudia A. Valente
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, 1648-028 Lisboa, Portugal; (M.V.Z.); (A.M.S.)
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1648-028 Lisboa, Portugal
- Correspondence:
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45
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Sharon A, Erez H, Spira ME. Significant Sex Differences in the Efficacy of the CSF1R Inhibitor-PLX5622 on Rat Brain Microglia Elimination. Pharmaceuticals (Basel) 2022; 15:569. [PMID: 35631395 PMCID: PMC9145577 DOI: 10.3390/ph15050569] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 12/30/2022] Open
Abstract
Microglia play pivotal roles in central nervous system development, homeostasis, responses to trauma, and neurodegenerative and neuropsychiatric disorders with significant sex-bias in their symptoms and prevalence. Survival of the microglia in adult brains depends on the expression of the colony-stimulating factor 1 receptor (CSF1R). The inhibition of CSF1R by brain-permeant PLX5622 in the chow eliminates, within 5-10 days, ~90% of the microglia in female and male mice, thereby enabling the investigation of the roles of the microglia in health and pathological mice models. Because of a prevailing "impression" that PLX5622 is ineffective in rats, it has hardly been used in studies of adult rats. Here, we report that effective microglia elimination by PLX5622-chow in rats is highly sex-dependent. Our observations provide missing information for the limited use and interpretation of PLX5622 in biomedical studies of the microglia in rat models. The sex differences that are too often overlooked must be carefully considered and clearly emphasized.
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Affiliation(s)
- Aviv Sharon
- Department of Neurobiology, Alexander Silberman Institute of Life Science, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel; (A.S.); (H.E.)
- The Charles E. Smith Family and Joel Elkes Laboratory for Collaborative Research in Psychobiology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Hadas Erez
- Department of Neurobiology, Alexander Silberman Institute of Life Science, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel; (A.S.); (H.E.)
- The Charles E. Smith Family and Joel Elkes Laboratory for Collaborative Research in Psychobiology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Micha E. Spira
- Department of Neurobiology, Alexander Silberman Institute of Life Science, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel; (A.S.); (H.E.)
- The Charles E. Smith Family and Joel Elkes Laboratory for Collaborative Research in Psychobiology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
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46
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Hohsfield LA, Tsourmas KI, Ghorbanian Y, Syage AR, Kim SJ, Cheng Y, Furman S, Inlay MA, Lane TE, Green KN. MAC2 is a long-lasting marker of peripheral cell infiltrates into the mouse CNS after bone marrow transplantation and coronavirus infection. Glia 2022; 70:875-891. [PMID: 35025109 PMCID: PMC8930563 DOI: 10.1002/glia.24144] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 01/03/2022] [Accepted: 01/05/2022] [Indexed: 01/09/2023]
Abstract
Microglia are the primary resident myeloid cells of the brain responsible for maintaining homeostasis and protecting the central nervous system (CNS) from damage and infection. Monocytes and monocyte-derived macrophages arising from the periphery have also been implicated in CNS pathologies, however, distinguishing between different myeloid cell populations in the CNS has been difficult. Here, we set out to develop a reliable histological marker that can assess distinct myeloid cell heterogeneity and functional contributions, particularly in the context of disease and/or neuroinflammation. scRNAseq from brains of mice infected with the neurotropic JHM strain of the mouse hepatitis virus (JHMV), a mouse coronavirus, revealed that Lgals3 is highly upregulated in monocyte and macrophage populations, but not in microglia. Subsequent immunostaining for galectin-3 (encoded by Lgals3), also referred to as MAC2, highlighted the high expression levels of MAC2 protein in infiltrating myeloid cells in JHMV-infected and bone marrow (BM) chimeric mice, in stark contrast to microglia, which expressed little to no staining in these models. Expression of MAC2 was found even 6-10 months following BM-derived cell infiltration into the CNS. We also demonstrate that MAC2 is not a specific label for plaque-associated microglia in the 5xFAD mouse model, but only appears in a distinct subset of these cells in the presence of JHMV infection or during aging. Our data suggest that MAC2 can serve as a reliable and long-lasting histological marker for monocyte/macrophages in the brain, identifying an accessible approach to distinguishing resident microglia from infiltrating cells in the CNS under certain conditions.
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Affiliation(s)
- Lindsay A. Hohsfield
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Kate Inman Tsourmas
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Yasamine Ghorbanian
- Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, CA 92697, USA
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA
| | - Amber R. Syage
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Sung Jin Kim
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Yuting Cheng
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Susana Furman
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Matthew A. Inlay
- Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, CA 92697, USA
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA
| | - Thomas E. Lane
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Kim N. Green
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
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47
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Du Y, Brennan FH, Popovich PG, Zhou M. Microglia maintain the normal structure and function of the hippocampal astrocyte network. Glia 2022; 70:1359-1379. [PMID: 35394085 PMCID: PMC9324808 DOI: 10.1002/glia.24179] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 03/09/2022] [Accepted: 03/28/2022] [Indexed: 12/14/2022]
Abstract
Microglial control of activity‐dependent plasticity and synaptic remodeling in neuronal networks has been the subject of intense research in the past several years. Although microglia–neuron interactions have been extensively studied, less is known about how microglia influence astrocyte‐dependent control over neuronal structure and function. Here, we explored a role for microglia in regulating the structure and function of the astrocyte syncytium in mouse hippocampus. After depleting microglia using a CSF1R antagonist (PLX5622, Plexxikon), we observed severe disruption of astrocyte syncytial isopotentiality and dye coupling. A decrease in astrocyte‐specific gap junction connexin (Cx) 30 and 43 expression, at least partially accounts for these microglia‐dependent changes in astrocytes. Because neuronal function requires intact astrocyte coupling, we also evaluated the effects of microglia depletion on synaptic transmission in the hippocampus. Without microglia, the strength of synaptic transmission was reduced at baseline and after long‐term potentiation (LTP). Conversely, priming microglia with systemic injections of lipopolysaccharide enhanced CA3‐CA1 synaptic transmission. This microglia‐induced scaling of synaptic transmission was associated with increased expression of post‐synaptic scaffold proteins (Homer1) in CA1. However, astrocyte network function was not affected by microglia priming, indicating that microglia‐dependent effects on astrocytes and neurons vary across functional states. Through manipulation of microglia in the brain, our results reveal the importance of microglia in homeostatic regulation of the astrocyte syncytium and scaling of synaptic transmission. These novel mechanisms uncover a new direction for future studies interrogating microglia function in various physiological and pathological contexts.
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Affiliation(s)
- Yixing Du
- Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Faith H Brennan
- Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA.,Center for Brain and Spinal Cord Repair, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Phillip G Popovich
- Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA.,Center for Brain and Spinal Cord Repair, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Min Zhou
- Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
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48
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Colony-stimulating factor 1 receptor signaling in the central nervous system and the potential of its pharmacological inhibitors to halt the progression of neurological disorders. Inflammopharmacology 2022; 30:821-842. [PMID: 35290551 DOI: 10.1007/s10787-022-00958-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 02/24/2022] [Indexed: 02/07/2023]
Abstract
Colony Stimulating Factor-1 (CSF-1)/Colony Stimulating Factor-1 Receptor (CSF-1R) signaling axis plays an essential role in the development, maintenance, and proliferation of macrophage lineage cells. Within the central nervous system, CSF-1R signaling primarily maintains microglial homeostasis. Microglia, being the resident macrophage and first responder to any neurological insults, plays critical importance in overall health of the human brain. Aberrant and sustained activation of microglia along with continued proliferation and release of neurotoxic proinflammatory cytokines have been reported in various neurological and neurodegenerative diseases. Therefore, halting the neuroinflammatory pathway via targeting microglial proliferation, which depends on CSF-1R signaling, has emerged as a potential therapeutic target for neurological disorders. However, apart from regulating the microglial function, recently it has been discovered that CSF-1R has much broader role in central nervous system. These findings limit the therapeutic utility of CSF-1R inhibitors but also highlight the need for a complete understanding of CSF-1R function within the central nervous system. Moreover, it has been found that selective inhibitors of CSF-1R may be more efficient in avoiding non-specific targeting and associated side effects. Short-term depletion of microglial population in diseased conditions have also been found to be beneficial; however, the dose and therapeutic window for optimum effects may need to be standardized further.This review summarizes the present understanding of CSF-1R function within the central nervous system. We discuss the CSF-1R signaling in the context of microglia function, crosstalk between microglia and astroglia, and regulation of neuronal cell function. We also discuss a few of the neurological disorders with a focus on the utility of CSF-1R inhibitors as potential therapeutic strategy for halting the progression of neurological diseases.
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49
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Acid-Sensing Ion Channels in Glial Cells. MEMBRANES 2022; 12:membranes12020119. [PMID: 35207041 PMCID: PMC8878633 DOI: 10.3390/membranes12020119] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 12/29/2021] [Accepted: 01/17/2022] [Indexed: 12/13/2022]
Abstract
Acid-sensing ion channels (ASICs) are proton-gated cation channels and key mediators of responses to neuronal injury. ASICs exhibit unique patterns of distribution in the brain, with high expression in neurons and low expression in glial cells. While there has been a lot of focus on ASIC in neurons, less is known about the roles of ASICs in glial cells. ASIC1a is expressed in astrocytes and might contribute to synaptic transmission and long-term potentiation. In oligodendrocytes, constitutive activation of ASIC1a participates in demyelinating diseases. ASIC1a, ASIC2a, and ASIC3, found in microglial cells, could mediate the inflammatory response. Under pathological conditions, ASIC dysregulation in glial cells can contribute to disease states. For example, activation of astrocytic ASIC1a may worsen neurodegeneration and glioma staging, activation of microglial ASIC1a and ASIC2a may perpetuate ischemia and inflammation, while oligodendrocytic ASIC1a might be involved in multiple sclerosis. This review concentrates on the unique ASIC components in each of the glial cells and integrates these glial-specific ASICs with their physiological and pathological conditions. Such knowledge provides promising evidence for targeting of ASICs in individual glial cells as a therapeutic strategy for a diverse range of conditions.
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50
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Barca C, Foray C, Hermann S, Herrlinger U, Remory I, Laoui D, Schäfers M, Grauer OM, Zinnhardt B, Jacobs AH. The Colony Stimulating Factor-1 Receptor (CSF-1R)-Mediated Regulation of Microglia/Macrophages as a Target for Neurological Disorders (Glioma, Stroke). Front Immunol 2021; 12:787307. [PMID: 34950148 PMCID: PMC8688767 DOI: 10.3389/fimmu.2021.787307] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/17/2021] [Indexed: 12/11/2022] Open
Abstract
Immunomodulatory therapies have fueled interest in targeting microglial cells as part of the innate immune response after infection or injury. In this context, the colony-stimulating factor 1 (CSF-1) and its receptor (CSF-1R) have gained attention in various neurological conditions to deplete and reprogram the microglia/macrophages compartment. Published data in physiological conditions support the use of small-molecule inhibitors to study microglia/macrophages dynamics under inflammatory conditions and as a therapeutic strategy in pathologies where those cells support disease progression. However, preclinical and clinical data highlighted that the complexity of the spatiotemporal inflammatory response could limit their efficiency due to compensatory mechanisms, ultimately leading to therapy resistance. We review the current state-of-art in the field of CSF-1R inhibition in glioma and stroke and provide an overview of the fundamentals, ongoing research, potential developments of this promising therapeutic strategy and further application toward molecular imaging.
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Affiliation(s)
- Cristina Barca
- European Institute for Molecular Imaging (EIMI), University of Münster, Münster, Germany
| | - Claudia Foray
- European Institute for Molecular Imaging (EIMI), University of Münster, Münster, Germany
| | - Sven Hermann
- European Institute for Molecular Imaging (EIMI), University of Münster, Münster, Germany
| | - Ulrich Herrlinger
- Division of Clinical Neuro-Oncology, Department of Neurology, University Hospital Bonn, Bonn, Germany.,Centre of Integrated Oncology, University Hospital Bonn, Bonn, Germany
| | - Isabel Remory
- In vivo Cellular and Molecular Imaging laboratory (ICMI), Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Damya Laoui
- Myeloid Cell Immunology Lab, VIB Center for Inflammation Research, Brussels, Belgium.,Lab of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Michael Schäfers
- European Institute for Molecular Imaging (EIMI), University of Münster, Münster, Germany.,Department of Nuclear Medicine, University Hospital Münster, Münster, Germany
| | - Oliver M Grauer
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany
| | - Bastian Zinnhardt
- European Institute for Molecular Imaging (EIMI), University of Münster, Münster, Germany.,Biomarkers & Translational Technologies (BTT), Pharma Research & Early Development (pRED), F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Andreas H Jacobs
- European Institute for Molecular Imaging (EIMI), University of Münster, Münster, Germany.,Centre of Integrated Oncology, University Hospital Bonn, Bonn, Germany.,Department of Geriatrics and Neurology, Johanniter Hospital, Bonn, Germany
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