1
|
Li J, Wang Z, Zhang Y, Li Y, Feng L, Wang J, Zhang J, Zhou Z, Zhang Y, Chang X. Effects of environmentally relevant concentration of short-chain chlorinated paraffins on BV2 microglia activation and lipid metabolism, implicating altered neurogenesis. ENVIRONMENTAL RESEARCH 2024; 251:118602. [PMID: 38431072 DOI: 10.1016/j.envres.2024.118602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 02/11/2024] [Accepted: 02/28/2024] [Indexed: 03/05/2024]
Abstract
Short-chain chlorinated paraffins (SCCPs), a class of persistent organic pollutants, have been found to cause diverse organ and systemic toxicity. However, little is known about their neurotoxic effects. In this study, we exposed BV2, a mouse microglia cell line, to environmentally relevant concentration of SCCPs (1 μg/L, 10 μg/L, 100 μg/L) for 24 h to investigate their impacts on the nervous system. Our observations revealed that SCCPs induced the activation of BV2 microglia, as indicated by altered morphology, stimulated cell proliferation, enhanced phagocytic and migratory capabilities. Analysis at the mRNA level confirmed the activation status, with the downregulation of TMEM119 and Tgfbr1, and upregulation of Iba1 and CD11b. The upregulated expression of genes such as cenpe, mki67, Axl, APOE and LPL also validated alterations in cell functions. Moreover, BV2 microglia presented an M2 alternative phenotype upon SCCPs exposure, substantiated by the reduction of NF-κB, TNF-α, IL-1β, and the elevation of TGF-β. Additionally, SCCPs caused lipid metabolic changes in BV2 microglia, characterized by the upregulations of long-chain fatty acids and acylcarnitines, reflecting an enhancement of β-oxidation. This aligns with our findings of increased ATP production upon SCCPs exposure. Intriguingly, cell activation coincided with elevated levels of omega-3 polyunsaturated fatty acids. Furthermore, activated microglial medium remarkably altered the proliferation and differentiation of mouse neural stem cells. Collectively, exposure to environmentally relevant concentrations of SCCPs resulted in activation and lipid metabolic alterations in BV2 microglia, potentially impacting neurogenesis. These findings provide valuable insights for further research on the neurotoxic effect of SCCPs.
Collapse
Affiliation(s)
- Jiayi Li
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Zheng Wang
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Yuwei Zhang
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Yixi Li
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Longfei Feng
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Jinglin Wang
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Jiming Zhang
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Zhijun Zhou
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Yunhui Zhang
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China.
| | - Xiuli Chang
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Fudan University, Shanghai, 200032, China.
| |
Collapse
|
2
|
Veneruso V, Petillo E, Pizzetti F, Orro A, Comolli D, De Paola M, Verrillo A, Baggiolini A, Votano S, Castiglione F, Sponchioni M, Forloni G, Rossi F, Veglianese P. Synergistic Pharmacological Therapy to Modulate Glial Cells in Spinal Cord Injury. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2307747. [PMID: 37990971 DOI: 10.1002/adma.202307747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 11/10/2023] [Indexed: 11/23/2023]
Abstract
Current treatments for modulating the glial-mediated inflammatory response after spinal cord injury (SCI) have limited ability to improve recovery. This is quite likely due to the lack of a selective therapeutic approach acting on microgliosis and astrocytosis, the glia components most involved after trauma, while maximizing efficacy and minimizing side effects. A new nanogel that can selectively release active compounds in microglial cells and astrocytes is developed and characterized. The degree of selectivity and subcellular distribution of the nanogel is evaluated by applying an innovative super-resolution microscopy technique, expansion microscopy. Two different administration schemes are then tested in a SCI mouse model: in an early phase, the nanogel loaded with Rolipram, an anti-inflammatory drug, achieves significant improvement in the animal's motor performance due to the increased recruitment of microglia and macrophages that are able to localize the lesion. Treatment in the late phase, however, gives opposite results, with worse motor recovery because of the widespread degeneration. These findings demonstrate that the nanovector can be selective and functional in the treatment of the glial component in different phases of SCI. They also open a new therapeutic scenario for tackling glia-mediated inflammation after neurodegenerative events in the central nervous system.
Collapse
Affiliation(s)
- Valeria Veneruso
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, via Mario Negri 2, Milano, 20156, Italy
- Faculty of Biomedical Sciences, Università della Svizzera Italiana, via Buffi 13, Lugano, 6900, Switzerland
| | - Emilia Petillo
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, via Mario Negri 2, Milano, 20156, Italy
| | - Fabio Pizzetti
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, Milano, 20131, Italy
| | - Alessandro Orro
- Department of Biomedical Sciences National Research Council, Institute for Biomedical Technologies, Via Fratelli Cervi 93, Segrate, 20054, Italy
| | - Davide Comolli
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, via Mario Negri 2, Milano, 20156, Italy
| | - Massimiliano De Paola
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, via Mario Negri 2, Milano, 20156, Italy
| | - Antonietta Verrillo
- Faculty of Biomedical Sciences, Università della Svizzera Italiana, via Buffi 13, Lugano, 6900, Switzerland
- Institute of Oncology Research (IOR), BIOS+, Via Francesco Chiesa 5, Bellinzona, 6500, Switzerland
| | - Arianna Baggiolini
- Faculty of Biomedical Sciences, Università della Svizzera Italiana, via Buffi 13, Lugano, 6900, Switzerland
- Institute of Oncology Research (IOR), BIOS+, Via Francesco Chiesa 5, Bellinzona, 6500, Switzerland
| | - Simona Votano
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, Milano, 20131, Italy
| | - Franca Castiglione
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, Milano, 20131, Italy
| | - Mattia Sponchioni
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, Milano, 20131, Italy
| | - Gianluigi Forloni
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, via Mario Negri 2, Milano, 20156, Italy
| | - Filippo Rossi
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, Milano, 20131, Italy
| | - Pietro Veglianese
- Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, via Mario Negri 2, Milano, 20156, Italy
- Faculty of Biomedical Sciences, Università della Svizzera Italiana, via Buffi 13, Lugano, 6900, Switzerland
| |
Collapse
|
3
|
Mohamed W, Kumar J, Alghamdi BS, Soliman AH, Toshihide Y. Neurodegeneration and inflammation crosstalk: Therapeutic targets and perspectives. IBRO Neurosci Rep 2023; 14:95-110. [PMID: 37388502 PMCID: PMC10300452 DOI: 10.1016/j.ibneur.2022.12.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 11/19/2022] [Accepted: 12/08/2022] [Indexed: 12/23/2022] Open
Abstract
Glia, which was formerly considered to exist just to connect neurons, now plays a key function in a wide range of physiological events, including formation of memory, learning, neuroplasticity, synaptic plasticity, energy consumption, and homeostasis of ions. Glial cells regulate the brain's immune responses and confers nutritional and structural aid to neurons, making them an important player in a broad range of neurological disorders. Alzheimer's, ALS, Parkinson's, frontotemporal dementia (FTD), and epilepsy are a few of the neurodegenerative diseases that have been linked to microglia and astroglia cells, in particular. Synapse growth is aided by glial cell activity, and this activity has an effect on neuronal signalling. Each glial malfunction in diverse neurodegenerative diseases is distinct, and we will discuss its significance in the progression of the illness, as well as its potential for future treatment.
Collapse
Affiliation(s)
- Wael Mohamed
- Department of Basic Medical Sciences, Kulliyyah of Medicine, International Islamic University Malaysia (IIUM), Kuantan, Malaysia
- Clinical Pharmacology Department, Menoufia Medical School, Menoufia University, Menoufia, Egypt
| | - Jaya Kumar
- Department of Physiology, Faculty of Medicine, UKM Medical Centre (UKMMC), Kuala Lumpur, Malaysia
| | | | | | | |
Collapse
|
4
|
Churchward MA, Michaud ER, Mullish BH, Miguens Blanco J, Garcia Perez I, Marchesi JR, Xu H, Kao D, Todd KG. Short-chain fatty and carboxylic acid changes associated with fecal microbiota transplant communally influence microglial inflammation. Heliyon 2023; 9:e16908. [PMID: 37484415 PMCID: PMC10360965 DOI: 10.1016/j.heliyon.2023.e16908] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 05/24/2023] [Accepted: 05/31/2023] [Indexed: 07/25/2023] Open
Abstract
The intestinal microbiota has been proposed to influence human mental health and cognition through the gut-brain axis. Individuals experiencing recurrent Clostridioides difficile infection (rCDI) frequently report depressive symptoms, which are improved after fecal microbiota transplantation (FMT); however, mechanisms underlying this association are poorly understood. Short-chain fatty acids and carboxylic acids (SCCA) produced by the intestinal microbiota cross the blood brain barrier and have been proposed to contribute to gut-brain communication. We hypothesized that changes in serum SCCA measured before and after successful FMT for rCDI influences the inflammatory response of microglia, the resident immune cells of the central nervous system. Serum SCCA were quantified using gas chromatography-mass spectroscopy from 38 patients who participated in a randomized trial comparing oral capsule-vs colonoscopy-delivered FMT for rCDI, and quality of life was assessed by SF-36 at baseline, 4, and 12 weeks after FMT treatment. Successful FMT was associated with improvements in mental and physical health, as well as significant changes in a number of circulating SCCA, including increased butyrate, 2-methylbutyrate, valerate, and isovalerate, and decreased 2-hydroxybutyrate. Primary cultured microglia were treated with SCCA and the response to a pro-inflammatory stimulus was measured. Treatment with a combination of SCCA based on the post-FMT serum profile, but not single SCCA species, resulted in significantly reduced inflammatory response including reduced cytokine release, reduced nitric oxide release, and accumulation of intracellular lipid droplets. This suggests that both levels and diversity of SCCA may be an important contributor to gut-brain communication.
Collapse
Affiliation(s)
- Matthew A. Churchward
- Department of Biological and Environmental Sciences, Concordia University of Edmonton, AB, T5B 4E4, Canada
- Neurochemical Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB, T6G 2R3, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, T6G 2R3, Canada
| | - Emily R. Michaud
- Neurochemical Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB, T6G 2R3, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, T6G 2R3, Canada
| | - Benjamin H. Mullish
- Division of Digestive Diseases, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, W2 1NY, UK
| | - Jesús Miguens Blanco
- Division of Digestive Diseases, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, W2 1NY, UK
| | - Isabel Garcia Perez
- Division of Digestive Diseases, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, W2 1NY, UK
| | - Julian R. Marchesi
- Division of Digestive Diseases, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, W2 1NY, UK
| | - Huiping Xu
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine Indianapolis, IN, USA, 46202
| | - Dina Kao
- Division of Gastroenterology, Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, T6G 2R3, Canada
| | - Kathryn G. Todd
- Neurochemical Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB, T6G 2R3, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, T6G 2R3, Canada
- Department of Biomedical Engineering, University of Alberta, Edmonton, AB, T6G 2R3, Canada
| |
Collapse
|
5
|
The role of ApoE-mediated microglial lipid metabolism in brain aging and disease. IMMUNOMETABOLISM (COBHAM (SURREY, ENGLAND)) 2023; 5:e00018. [PMID: 36710921 PMCID: PMC9869962 DOI: 10.1097/in9.0000000000000018] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 12/20/2022] [Indexed: 01/31/2023]
Abstract
Microglia are a unique population of immune cells resident in the brain that integrate complex signals and dynamically change phenotypes in response to the brain microenvironment. In recent years, single-cell sequencing analyses have revealed profound cellular heterogeneity and context-specific transcriptional plasticity of microglia during brain development, aging, and disease. Emerging evidence suggests that microglia adapt phenotypic plasticity by flexibly reprogramming cellular metabolism to fulfill distinct immune functions. The control of lipid metabolism is central to the appropriate function and homeostasis of the brain. Microglial lipid metabolism regulated by apolipoprotein E (ApoE), a crucial lipid transporter in the brain, has emerged as a critical player in regulating neuroinflammation. The ApoE gene allelic variant, ε4, is associated with a greater risk for neurodegenerative diseases. In this review, we explore novel discoveries in microglial lipid metabolism mediated by ApoE. We elaborate on the functional impact of perturbed microglial lipid metabolism on the underlying pathogenesis of brain aging and disease.
Collapse
|
6
|
Yang D, Wang X, Zhang L, Fang Y, Zheng Q, Liu X, Yu W, Chen S, Ying J, Hua F. Lipid metabolism and storage in neuroglia: role in brain development and neurodegenerative diseases. Cell Biosci 2022; 12:106. [PMID: 35831869 PMCID: PMC9277953 DOI: 10.1186/s13578-022-00828-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 06/05/2022] [Indexed: 11/13/2022] Open
Abstract
The importance of neuroglia in maintaining normal brain function under physiological and pathological conditions has been supported by growing evidence in recent years. The most important issues regarding glial metabolism and function include the cooperation between glial populations and neurons, morphological and functional changes in pathological states, and the role in the onset and progression of neurodegenerative diseases. Although lipid accumulation and further lipid droplet production in neurodegenerative disease brain models have been observed for a long time, the dynamic development of brain lipid droplet research in recent years suggests its role in the development and progression of neurodegenerative diseases was previously underestimated. First recognized as organelles of lipid storage, lipid droplets (LDs) have emerged as an important organelle in metabolic diseases, inflammation, and host defense. Dynamic changes in lipid metabolism within neurons and glial cells resulting in lipid accumulation and lipid droplet formation are present in brain models of various neurodegenerative diseases, yet their role in the brain remains largely unexplored. This paper first reviews the metabolism and accumulation of several major lipids in the brain and discusses the regulation of lipid accumulation in different types of brain cells. We explore the potential role of intracellular lipid accumulation in the pathogenesis of neurodegeneration, starting from lipid metabolism and LDs biogenesis in glial cells, and discuss several pathological factors that promote lipid droplet formation, mainly focusing on oxidative stress, energy metabolism and glial cell-neuron coupling, which are closely related to the etiology and progression of neurodegenerative diseases. Finally, the directions and challenges of intracellular lipid metabolism in glial cells in neurodegeneration are discussed.
Collapse
|
7
|
Reactive Microgliosis in Sepsis-Associated and Acute Hepatic Encephalopathies: An Ultrastructural Study. Int J Mol Sci 2022; 23:ijms232214455. [PMID: 36430933 PMCID: PMC9696099 DOI: 10.3390/ijms232214455] [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: 10/12/2022] [Revised: 11/17/2022] [Accepted: 11/19/2022] [Indexed: 11/23/2022] Open
Abstract
Sepsis and acute liver failure are associated with severe endogenous intoxication. Microglia, which are the resident immune brain cells, play diverse roles in central nervous system development, surveillance, and defense, as well as contributing to neuroinflammatory reactions. In particular, microglia are fundamental to the pathophysiology of reactive toxic encephalopathies. We analyzed microglial ultrastructure, morphotypes, and phagocytosis in the sensorimotor cortex of cecal ligation and puncture (CLP) and acetaminophen-induced liver failure (AILF) Wistar rats. A CLP model induced a gradual shift of ~50% of surveillant microglia to amoeboid hypertrophic-like and gitter cell-like reactive phenotypes with active phagocytosis and frequent contacts with damaged neurons. In contrast, AILF microglia exhibited amoeboid, rod-like, and hypertrophic-like reactive morphotypes with minimal indications for efficient phagocytosis, and were mostly in contact with edematous astrocytes. Close interactions of reactive microglia with neurons, astrocytes, and blood-brain barrier components reflect an active contribution of these cells to the tissue adaptation and cellular remodeling to toxic brain damage. Partial disability of reactive microglia may affect the integrity and metabolism in all tissue compartments, leading to failure of the compensatory mechanisms in acute endogenous toxic encephalopathies.
Collapse
|
8
|
Cirulli F, De Simone R, Musillo C, Ajmone-Cat MA, Berry A. Inflammatory Signatures of Maternal Obesity as Risk Factors for Neurodevelopmental Disorders: Role of Maternal Microbiota and Nutritional Intervention Strategies. Nutrients 2022; 14:nu14153150. [PMID: 35956326 PMCID: PMC9370669 DOI: 10.3390/nu14153150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 07/18/2022] [Accepted: 07/28/2022] [Indexed: 02/01/2023] Open
Abstract
Obesity is a main risk factor for the onset and the precipitation of many non-communicable diseases. This condition, which is associated with low-grade chronic systemic inflammation, is of main concern during pregnancy leading to very serious consequences for the new generations. In addition to the prominent role played by the adipose tissue, dysbiosis of the maternal gut may also sustain the obesity-related inflammatory milieu contributing to create an overall suboptimal intrauterine environment. Such a condition here generically defined as “inflamed womb” may hold long-term detrimental effects on fetal brain development, increasing the vulnerability to mental disorders. In this review, we will examine the hypothesis that maternal obesity-related gut dysbiosis and the associated inflammation might specifically target fetal brain microglia, the resident brain immune macrophages, altering neurodevelopmental trajectories in a sex-dependent fashion. We will also review some of the most promising nutritional strategies capable to prevent or counteract the effects of maternal obesity through the modulation of inflammation and oxidative stress or by targeting the maternal microbiota.
Collapse
Affiliation(s)
- Francesca Cirulli
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy; or
- Correspondence: (F.C.); (A.B.)
| | - Roberta De Simone
- National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy; (R.D.S.); (M.A.A.-C.)
| | - Chiara Musillo
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy; or
- PhD Program in Behavioral Neuroscience, Department of Psychology, Sapienza University of Rome, 00185 Rome, Italy
| | - Maria Antonietta Ajmone-Cat
- National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy; (R.D.S.); (M.A.A.-C.)
| | - Alessandra Berry
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy; or
- Correspondence: (F.C.); (A.B.)
| |
Collapse
|
9
|
Age-Associated Glia Remodeling and Mitochondrial Dysfunction in Neurodegeneration: Antioxidant Supplementation as a Possible Intervention. Nutrients 2022; 14:nu14122406. [PMID: 35745134 PMCID: PMC9230668 DOI: 10.3390/nu14122406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/06/2022] [Accepted: 06/07/2022] [Indexed: 02/07/2023] Open
Abstract
Aging induces substantial remodeling of glia, including density, morphology, cytokine expression, and phagocytic capacity. Alterations of glial cells, such as hypertrophy of lysosomes, endosomes and peroxisomes, and the progressive accumulation of lipofuscin, lipid droplets, and other debris have also been reported. These abnormalities have been associated with significant declines of microglial processes and reduced ability to survey the surrounding tissue, maintain synapses, and recover from injury. Similarly, aged astrocytes show reduced capacity to support metabolite transportation to neurons. In the setting of reduced glial activity, stressors and/or injury signals can trigger a coordinated action of microglia and astrocytes that may amplify neuroinflammation and contribute to the release of neurotoxic factors. Oxidative stress and proteotoxic aggregates may burst astrocyte-mediated secretion of pro-inflammatory cytokines, thus activating microglia, favoring microgliosis, and ultimately making the brain more susceptible to injury and/or neurodegeneration. Here, we discuss the contribution of microglia and astrocyte oxidative stress to neuroinflammation and neurodegeneration, highlight the pathways that may help gain insights into their molecular mechanisms, and describe the benefits of antioxidant supplementation-based strategies.
Collapse
|
10
|
Bai Q, Yang X, Li Q, Chen W, Tian H, Lian R, Liu X, Wang S, Yang Y. Metastatic Tumor Cell-Specific FABP7 Promotes NSCLC Metastasis via Inhibiting β-Catenin Degradation. Cells 2022; 11:cells11050805. [PMID: 35269427 PMCID: PMC8909100 DOI: 10.3390/cells11050805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/16/2022] [Accepted: 02/22/2022] [Indexed: 02/04/2023] Open
Abstract
Metastasis accounts for 90% of cancer-related deaths and represents a prominent malignant feature in non-small cell lung cancer (NSCLC), while tumor cell-specific mechanisms and molecules pivotal for the metastatic capacity remain unclear. By analyzing single-cell RNA sequencing data, we found that fatty acid binding protein 7 (FABP7) was specifically up-regulated in tumor cells of metastatic NSCLC patients and might be a prognostic indicator for poor survival. Experimental studies based on NSCLC cell lines showed that FABP7 promoted the metastatic competencies of NSCLC cells in vitro and in vivo. Mechanistically, we demonstrated that FABP7 was important to canonical Wnt signaling activation and competitively inhibited the interaction between β-catenin and components of its cytoplasmic degradation complex, thereby repressing the phosphorylation-dependent ubiquitination and degradation of β-catenin. Our present study identifies FABP7 as a metastatic tumor cell-specific pro-metastatic gene and uncovers a previously unknown regulatory mechanism underlying Wnt hyperactivation via FABP7-impaired cytoplasmic β-catenin degradation, implicating a novel molecule in regulating NSCLC metastasis.
Collapse
Affiliation(s)
- Qiaorui Bai
- Department of Basic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China;
| | - Xia Yang
- Department of Microbiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; (X.Y.); (X.L.); (S.W.)
| | - Quanfeng Li
- Cancer Institute, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China;
| | - Weizhong Chen
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China;
| | - Han Tian
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China;
| | - Rong Lian
- Key Laboratory of Tropical Disease Control, Ministry of Education, Sun Yat-sen University, Guangzhou 510080, China;
| | - Ximeng Liu
- Department of Microbiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; (X.Y.); (X.L.); (S.W.)
| | - Shuang Wang
- Department of Microbiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; (X.Y.); (X.L.); (S.W.)
| | - Yi Yang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China;
- Correspondence: ; Tel./Fax: +86-20-8733-5868
| |
Collapse
|
11
|
Pathophysiology of Lipid Droplets in Neuroglia. Antioxidants (Basel) 2021; 11:antiox11010022. [PMID: 35052526 PMCID: PMC8773017 DOI: 10.3390/antiox11010022] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 12/12/2022] Open
Abstract
In recent years, increasing evidence regarding the functional importance of lipid droplets (LDs), cytoplasmic storage organelles in the central nervous system (CNS), has emerged. Although not abundantly present in the CNS under normal conditions in adulthood, LDs accumulate in the CNS during development and aging, as well as in some neurologic disorders. LDs are actively involved in cellular lipid turnover and stress response. By regulating the storage of excess fatty acids, cholesterol, and ceramides in addition to their subsequent release in response to cell needs and/or environmental stressors, LDs are involved in energy production, in the synthesis of membranes and signaling molecules, and in the protection of cells against lipotoxicity and free radicals. Accumulation of LDs in the CNS appears predominantly in neuroglia (astrocytes, microglia, oligodendrocytes, ependymal cells), which provide trophic, metabolic, and immune support to neuronal networks. Here we review the most recent findings on the characteristics and functions of LDs in neuroglia, focusing on astrocytes, the key homeostasis-providing cells in the CNS. We discuss the molecular mechanisms affecting LD turnover in neuroglia under stress and how this may protect neural cell function. We also highlight the role (and potential contribution) of neuroglial LDs in aging and in neurologic disorders.
Collapse
|
12
|
Blaylock RL. Covid-19 pandemic: What is the truth? Surg Neurol Int 2021; 12:591. [PMID: 34992908 PMCID: PMC8720447 DOI: 10.25259/sni_1008_2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 10/27/2021] [Indexed: 12/12/2022] Open
Abstract
The ongoing “pandemic” involving the severe acute respiratory syndrome coronavirus 2 virus (SARS-CoV-2) has several characteristics that make it unique in the history of pandemics. This entails not only the draconian measures that some countries and individual states within the United States and initiated and made policy, most of which are without precedent or scientific support, but also the completely unscientific way the infection has been handled. For the 1st time in medical history, major experts in virology, epidemiology, infectious diseases, and vaccinology have not only been ignored, but are also demonized, marginalized and in some instances, become the victim of legal measures that can only be characterized as totalitarian. Discussions involving various scientific opinions have been eliminated, top scientists have been frightened into silence by threats to their careers, physicians have lost their licenses, and the concept of early treatment has been virtually eliminated. Hundreds of thousands of people have died needlessly as a result of, in my opinion and the opinion of others, poorly designed treatment protocols, mostly stemming from the Center for Disease Control and Prevention, which have been rigidly enforced among all hospitals. The economic, psychological, and institutional damage caused by these unscientific policies is virtually unmeasurable. Whole generations of young people will suffer irreparable damage, both physical and psychological, possibly forever. The truth must be told.
Collapse
|
13
|
Enlow W, Bordeleau M, Piret J, Ibáñez FG, Uyar O, Venable MC, Goyette N, Carbonneau J, Tremblay ME, Boivin G. Microglia are involved in phagocytosis and extracellular digestion during Zika virus encephalitis in young adult immunodeficient mice. J Neuroinflammation 2021; 18:178. [PMID: 34399779 PMCID: PMC8369691 DOI: 10.1186/s12974-021-02221-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 07/16/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Zika virus (ZIKV) has been associated with several neurological complications in adult patients. METHODS We used a mouse model deficient in TRIF and IPS-1 adaptor proteins, which are involved in type I interferon production, to study the role of microglia during brain infection by ZIKV. Young adult mice were infected intravenously with the contemporary ZIKV strain PRVABC59 (1 × 105 PFUs/100 µL). RESULTS Infected mice did not present overt clinical signs of the disease nor body weight loss compared with noninfected animals. However, mice exhibited a viremia and a brain viral load that were maximal (1.3 × 105 genome copies/mL and 9.8 × 107 genome copies/g of brain) on days 3 and 7 post-infection (p.i.), respectively. Immunohistochemistry analysis showed that ZIKV antigens were distributed in several regions of the brain, especially the dorsal hippocampus. The number of Iba1+/TMEM119+ microglia remained similar in infected versus noninfected mice, but their cell body and arborization areas significantly increased in the stratum radiatum and stratum lacunosum-moleculare layers of the dorsal hippocampus cornu ammoni (CA)1, indicating a reactive state. Ultrastructural analyses also revealed that microglia displayed increased phagocytic activities and extracellular digestion of degraded elements during infection. Mice pharmacologically depleted in microglia with PLX5622 presented a higher brain viral load compared to untreated group (2.8 × 1010 versus 8.5 × 108 genome copies/g of brain on day 10 p.i.) as well as an increased number of ZIKV antigens labeled with immunogold in the cytoplasm and endoplasmic reticulum of neurons and astrocytes indicating an enhanced viral replication. Furthermore, endosomes of astrocytes contained nanogold particles together with digested materials, suggesting a compensatory phagocytic activity upon microglial depletion. CONCLUSIONS These results indicate that microglia are involved in the control of ZIKV replication and/or its elimination in the brain. After depletion of microglia, the removal of ZIKV-infected cells by phagocytosis could be partly compensated by astrocytes.
Collapse
Affiliation(s)
- William Enlow
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
| | - Maude Bordeleau
- Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada.,Neurosciences Axis, Centre de recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
| | - Jocelyne Piret
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
| | - Fernando González Ibáñez
- Neurosciences Axis, Centre de recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada.,Department of Molecular Medicine, Université Laval, Quebec City, QC, Canada.,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Olus Uyar
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
| | - Marie-Christine Venable
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
| | - Nathalie Goyette
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
| | - Julie Carbonneau
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
| | - Marie-Eve Tremblay
- Neurosciences Axis, Centre de recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada. .,Department of Molecular Medicine, Université Laval, Quebec City, QC, Canada. .,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada. .,Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada. .,Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada.
| | - Guy Boivin
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada.
| |
Collapse
|
14
|
Choi WS, Xu X, Goruk S, Wang Y, Patel S, Chow M, Field CJ, Godbout R. FABP7 Facilitates Uptake of Docosahexaenoic Acid in Glioblastoma Neural Stem-like Cells. Nutrients 2021; 13:2664. [PMID: 34444824 PMCID: PMC8402214 DOI: 10.3390/nu13082664] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/26/2021] [Accepted: 07/29/2021] [Indexed: 01/14/2023] Open
Abstract
Glioblastoma (GBM) is an aggressive tumor with a dismal prognosis. Neural stem-like cells contribute to GBM's poor prognosis by driving drug resistance and maintaining cellular heterogeneity. GBM neural stem-like cells express high levels of brain fatty acid-binding protein (FABP7), which binds to polyunsaturated fatty acids (PUFAs) ω-6 arachidonic acid (AA) and ω-3 docosahexaenoic acid (DHA). Similar to brain, GBM tissue is enriched in AA and DHA. However, DHA levels are considerably lower in GBM tissue compared to adult brain. Therefore, it is possible that increasing DHA content in GBM, particularly in neural stem-like cells, might have therapeutic value. Here, we examine the fatty acid composition of patient-derived GBM neural stem-like cells grown as neurosphere cultures. We also investigate the effect of AA and DHA treatment on the fatty acid profiles of GBM neural stem-like cells with or without FABP7 knockdown. We show that DHA treatment increases DHA levels and the DHA:AA ratio in GBM neural stem-like cells, with FABP7 facilitating the DHA uptake. We also found that an increased uptake of DHA inhibits the migration of GBM neural stem-like cells. Our results suggest that increasing DHA content in the GBM microenvironment may reduce the migration/infiltration of FABP7-expressing neural stem-like cancer cells.
Collapse
Affiliation(s)
- Won-Shik Choi
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB T6G 1Z2, Canada; (W.-S.C.); (X.X.); (Y.W.); (S.P.)
| | - Xia Xu
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB T6G 1Z2, Canada; (W.-S.C.); (X.X.); (Y.W.); (S.P.)
| | - Susan Goruk
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2E1, Canada; (S.G.); (C.J.F.)
| | - Yixiong Wang
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB T6G 1Z2, Canada; (W.-S.C.); (X.X.); (Y.W.); (S.P.)
| | - Samir Patel
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB T6G 1Z2, Canada; (W.-S.C.); (X.X.); (Y.W.); (S.P.)
| | - Michael Chow
- Department of Surgery, University of Alberta, Edmonton, AB T6G 2B7, Canada;
| | - Catherine J. Field
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2E1, Canada; (S.G.); (C.J.F.)
| | - Roseline Godbout
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB T6G 1Z2, Canada; (W.-S.C.); (X.X.); (Y.W.); (S.P.)
| |
Collapse
|
15
|
Ralhan I, Chang CL, Lippincott-Schwartz J, Ioannou MS. Lipid droplets in the nervous system. J Cell Biol 2021; 220:e202102136. [PMID: 34152362 PMCID: PMC8222944 DOI: 10.1083/jcb.202102136] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/31/2021] [Accepted: 06/01/2021] [Indexed: 01/20/2023] Open
Abstract
Lipid droplets are dynamic intracellular lipid storage organelles that respond to the physiological state of cells. In addition to controlling cell metabolism, they play a protective role for many cellular stressors, including oxidative stress. Despite prior descriptions of lipid droplets appearing in the brain as early as a century ago, only recently has the role of lipid droplets in cells found in the brain begun to be understood. Lipid droplet functions have now been described for cells of the nervous system in the context of development, aging, and an increasing number of neuropathologies. Here, we review the basic mechanisms of lipid droplet formation, turnover, and function and discuss how these mechanisms enable lipid droplets to function in different cell types of the nervous system under healthy and pathological conditions.
Collapse
Affiliation(s)
- Isha Ralhan
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
- Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada
| | - Chi-Lun Chang
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA
| | | | - Maria S. Ioannou
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
- Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| |
Collapse
|
16
|
Microglial heterogeneity in aging and Alzheimer's disease: Is sex relevant? J Pharmacol Sci 2021; 146:169-181. [PMID: 34030799 DOI: 10.1016/j.jphs.2021.03.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 02/24/2021] [Accepted: 03/22/2021] [Indexed: 02/08/2023] Open
Abstract
Neurodegenerative diseases and their associated cognitive decline are known to be more prevalent during aging. Recent evidence has uncovered the role of microglia, the immunocompetent cells of the brain, in dysfunctions linked to neurodegenerative diseases such as is Alzheimer's disease (AD). Similar to other pathologies, AD is shown to be sex-biased, with females being more at risk compared to males. While the mechanisms driving this prevalence are still unclear, emerging data suggest the sex differences present in microglia throughout life might lead to different responses of these cells in both health and disease. Furthermore, microglial cells have recently been recognized as a deeply heterogeneous population, with multiple subsets and/or phenotypes stemming from diverse parameters such as age, sex or state of health. Therefore, this review discusses microglial heterogeneity during aging in both basal conditions and AD with a focus on existing sex differences in this process.
Collapse
|
17
|
Gran ER, Bertorelle F, Fakhouri H, Antoine R, Perić Bakulić M, Sanader Maršić Ž, Bonačić-Koutecký V, Blain M, Antel J, Maysinger D. Size and ligand effects of gold nanoclusters in alteration of organellar state and translocation of transcription factors in human primary astrocytes. NANOSCALE 2021; 13:3173-3183. [PMID: 33527928 DOI: 10.1039/d0nr06401g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Ultra-small gold nanoclusters (AuNCs) with designed sizes and ligands are gaining popularity for biomedical purposes and ultimately for human imaging and therapeutic applications. Human non-tumor brain cells, astrocytes, are of particular interest because they are abundant and play a role in functional regulation of neurons under physiological and pathological conditions. Human primary astrocytes were treated with AuNCs of varying sizes (Au10, Au15, Au18, Au25) and ligand composition (glutathione, polyethylene glycol, N-acetyl cysteine). Concentration and time-dependent studies showed no significant cell loss with AuNC concentrations <10 μM. AuNC treatment caused marked differential astrocytic responses at the organellar and transcription factor level. The effects were exacerbated under severe oxidative stress induced by menadione. Size-dependent effects were most remarkable with the smallest and largest AuNCs (10, 15 Au atoms versus 25 Au atoms) and might be related to the accessibility of biological targets toward the AuNC core, as demonstrated by QM/MM simulations. In summary, these findings suggest that AuNCs are not inert in primary human astrocytes, and that their sizes play a critical role in modulation of organellar and redox-responsive transcription factor homeostasis.
Collapse
Affiliation(s)
- Evan Rizzel Gran
- Department of Pharmacology & Therapeutics, McGill University, Montréal, QC H3G 1Y6, Canada.
| | - Franck Bertorelle
- Institut Lumière Matière UMR 5306, Université Claude Bernard Lyon 1, CNRS, Univ Lyon, F-69100 Villeurbanne, France.
| | - Hussein Fakhouri
- Institut Lumière Matière UMR 5306, Université Claude Bernard Lyon 1, CNRS, Univ Lyon, F-69100 Villeurbanne, France.
| | - Rodolphe Antoine
- Institut Lumière Matière UMR 5306, Université Claude Bernard Lyon 1, CNRS, Univ Lyon, F-69100 Villeurbanne, France.
| | - Martina Perić Bakulić
- Center of Excellence for Science and Technology-Integration of Mediterranean Region (STIM), Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia
| | - Željka Sanader Maršić
- Center of Excellence for Science and Technology-Integration of Mediterranean Region (STIM), Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia and Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Republic of Croatia
| | - Vlasta Bonačić-Koutecký
- Center of Excellence for Science and Technology-Integration of Mediterranean Region (STIM), Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia and Interdisciplinary Center for Advanced Science and Technology (ICAST) at University of Split, Meštrovićevo šetalište 45, 21000 Split, Croatia and Chemistry Department, Humboldt University of Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Manon Blain
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada
| | - Jack Antel
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada
| | - Dusica Maysinger
- Department of Pharmacology & Therapeutics, McGill University, Montréal, QC H3G 1Y6, Canada.
| |
Collapse
|
18
|
Loving BA, Tang M, Neal MC, Gorkhali S, Murphy R, Eckel RH, Bruce KD. Lipoprotein Lipase Regulates Microglial Lipid Droplet Accumulation. Cells 2021; 10:cells10020198. [PMID: 33498265 PMCID: PMC7909280 DOI: 10.3390/cells10020198] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 12/18/2022] Open
Abstract
Microglia become increasingly dysfunctional with aging and contribute to the onset of neurodegenerative disease (NDs) through defective phagocytosis, attenuated cholesterol efflux, and excessive secretion of pro-inflammatory cytokines. Dysfunctional microglia also accumulate lipid droplets (LDs); however, the mechanism underlying increased LD load is unknown. We have previously shown that microglia lacking lipoprotein lipase (LPL KD) are polarized to a pro-inflammatory state and have impaired lipid uptake and reduced fatty acid oxidation (FAO). Here, we also show that LPL KD microglia show excessive accumulation of LD-like structures. Moreover, LPL KD microglia display a pro-inflammatory lipidomic profile, increased cholesterol ester (CE) content, and reduced cholesterol efflux at baseline. We also show reduced expression of genes within the canonical cholesterol efflux pathway. Importantly, PPAR agonists (rosiglitazone and bezafibrate) rescued the LD-associated phenotype in LPL KD microglia. These data suggest that microglial-LPL is associated with lipid uptake, which may drive PPAR signaling and cholesterol efflux to prevent inflammatory lipid distribution and LD accumulation. Moreover, PPAR agonists can reverse LD accumulation, and therefore may be beneficial in aging and in the treatment of NDs.
Collapse
Affiliation(s)
- Bailey A. Loving
- Department of Radiation Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, MI 48309, USA;
| | - Maoping Tang
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
| | - Mikaela C. Neal
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
| | - Sachi Gorkhali
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
| | - Robert Murphy
- Department of Pharmacology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Robert H. Eckel
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
| | - Kimberley D. Bruce
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA; (M.T.); (M.C.N.); (S.G.); (R.H.E.)
- Correspondence:
| |
Collapse
|
19
|
da Silva Chagas L, Sandre PC, de Velasco PC, Marcondes H, Ribeiro E Ribeiro NCA, Barreto AL, Alves Mauro LB, Ferreira JH, Serfaty CA. Neuroinflammation and Brain Development: Possible Risk Factors in COVID-19-Infected Children. Neuroimmunomodulation 2021; 28:22-28. [PMID: 33530091 PMCID: PMC7900470 DOI: 10.1159/000512815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 11/01/2020] [Indexed: 11/19/2022] Open
Abstract
COVID-19, a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) betacoronavirus, affects children in a different way than it does in adults, with milder symptoms. However, several cases of neurological symptoms with neuroinflammatory syndromes, such as the multisystem inflammatory syndrome (MIS-C), following mild cases, have been reported. As with other viral infections, such as rubella, influenza, and cytomegalovirus, SARS-CoV-2 induces a surge of proinflammatory cytokines that affect microglial function, which can be harmful to brain development. Along with the viral induction of neuroinflammation, other noninfectious conditions may interact to produce additional inflammation, such as the nutritional imbalance of fatty acids and polyunsaturated fatty acids and alcohol consumption during pregnancy. Additionally, transient thyrotoxicosis induced by SARS-CoV-2 with secondary autoimmune hypothyroidism has been reported, which could go undetected during pregnancy. Together, those factors may pose additional risk factors for SARS-CoV-2 infection impacting mechanisms of neural development such as synaptic pruning and neural circuitry formation. The present review discusses those conditions in the perspective of the understanding of risk factors that should be considered and the possible emergence of neurodevelopmental disorders in COVID-19-infected children.
Collapse
Affiliation(s)
- Luana da Silva Chagas
- Laboratory of Neural Plasticity, Neurobiology Department, Biology Institute, Federal Fluminense University, Niteroi, Brazil
| | - Poliana Capucho Sandre
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Patricia Coelho de Velasco
- Department of Applied Nutrition, Institute of Nutrition, Rio de Janeiro State University, Rio de Janeiro, Brazil
| | - Henrique Marcondes
- Laboratory of Neural Plasticity, Neurobiology Department, Biology Institute, Federal Fluminense University, Niteroi, Brazil
| | | | - Aline Loureiro Barreto
- Laboratory of Neural Plasticity, Neurobiology Department, Biology Institute, Federal Fluminense University, Niteroi, Brazil
| | - Luiza Beatriz Alves Mauro
- Laboratory of Neural Plasticity, Neurobiology Department, Biology Institute, Federal Fluminense University, Niteroi, Brazil
| | - Julia Huber Ferreira
- Laboratory of Neural Plasticity, Neurobiology Department, Biology Institute, Federal Fluminense University, Niteroi, Brazil
| | - Claudio A Serfaty
- Laboratory of Neural Plasticity, Neurobiology Department, Biology Institute, Federal Fluminense University, Niteroi, Brazil,
- National Institute of Science and Technology on Neuroimmunomodulation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil,
| |
Collapse
|
20
|
Madore C, Leyrolle Q, Morel L, Rossitto M, Greenhalgh AD, Delpech JC, Martinat M, Bosch-Bouju C, Bourel J, Rani B, Lacabanne C, Thomazeau A, Hopperton KE, Beccari S, Sere A, Aubert A, De Smedt-Peyrusse V, Lecours C, Bisht K, Fourgeaud L, Gregoire S, Bretillon L, Acar N, Grant NJ, Badaut J, Gressens P, Sierra A, Butovsky O, Tremblay ME, Bazinet RP, Joffre C, Nadjar A, Layé S. Essential omega-3 fatty acids tune microglial phagocytosis of synaptic elements in the mouse developing brain. Nat Commun 2020; 11:6133. [PMID: 33257673 PMCID: PMC7704669 DOI: 10.1038/s41467-020-19861-z] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/03/2020] [Indexed: 12/23/2022] Open
Abstract
Omega-3 fatty acids (n-3 PUFAs) are essential for the functional maturation of the brain. Westernization of dietary habits in both developed and developing countries is accompanied by a progressive reduction in dietary intake of n-3 PUFAs. Low maternal intake of n-3 PUFAs has been linked to neurodevelopmental diseases in Humans. However, the n-3 PUFAs deficiency-mediated mechanisms affecting the development of the central nervous system are poorly understood. Active microglial engulfment of synapses regulates brain development. Impaired synaptic pruning is associated with several neurodevelopmental disorders. Here, we identify a molecular mechanism for detrimental effects of low maternal n-3 PUFA intake on hippocampal development in mice. Our results show that maternal dietary n-3 PUFA deficiency increases microglia-mediated phagocytosis of synaptic elements in the rodent developing hippocampus, partly through the activation of 12/15-lipoxygenase (LOX)/12-HETE signaling, altering neuronal morphology and affecting cognitive performance of the offspring. These findings provide a mechanistic insight into neurodevelopmental defects caused by maternal n-3 PUFAs dietary deficiency.
Collapse
Affiliation(s)
- C Madore
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women´s Hospital, Harvard Medical School, Boston, MA, USA
| | - Q Leyrolle
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
- NeuroDiderot, Inserm, Université de Paris Diderot, F-75019, Paris, France
| | - L Morel
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - M Rossitto
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - A D Greenhalgh
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - J C Delpech
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - M Martinat
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - C Bosch-Bouju
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - J Bourel
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - B Rani
- Department of Health Sciences, University of Florence, Florence, Italy
| | - C Lacabanne
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - A Thomazeau
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - K E Hopperton
- Department of Nutritional Sciences, University of Toronto, Toronto, ON, M5S 3E2, Canada
| | - S Beccari
- Achucarro Basque Center for Neuroscience, University of the Basque Country and Ikerbasque Foundation, 48940, Leioa, Spain
| | - A Sere
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - A Aubert
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - V De Smedt-Peyrusse
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - C Lecours
- Neurosciences Axis, CRCHU de Québec-Université Laval, Québec City, QC, Canada
| | - K Bisht
- Neurosciences Axis, CRCHU de Québec-Université Laval, Québec City, QC, Canada
| | - L Fourgeaud
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - S Gregoire
- Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
| | - L Bretillon
- Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
| | - N Acar
- Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Univ. Bourgogne Franche-Comté, F-21000, Dijon, France
| | - N J Grant
- CNRS UPR3212, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - J Badaut
- CNRS UMR5287, University of Bordeaux, Bordeaux, France
| | - P Gressens
- NeuroDiderot, Inserm, Université de Paris Diderot, F-75019, Paris, France
- Centre for the Developing Brain, Department of Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, SE1 7EH, UK
| | - A Sierra
- Achucarro Basque Center for Neuroscience, University of the Basque Country and Ikerbasque Foundation, 48940, Leioa, Spain
| | - O Butovsky
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women´s Hospital, Harvard Medical School, Boston, MA, USA
- Evergrande Center for Immunologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - M E Tremblay
- Neurosciences Axis, CRCHU de Québec-Université Laval, Québec City, QC, Canada
| | - R P Bazinet
- Department of Nutritional Sciences, University of Toronto, Toronto, ON, M5S 3E2, Canada
| | - C Joffre
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France
| | - A Nadjar
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France.
| | - S Layé
- Univ. Bordeaux, INRAE, Bordeaux INP, NutriNeuro, UMR 1286, F-33000, Bordeaux, France.
| |
Collapse
|
21
|
Chausse B, Kakimoto PA, Kann O. Microglia and lipids: how metabolism controls brain innate immunity. Semin Cell Dev Biol 2020; 112:137-144. [PMID: 32807643 DOI: 10.1016/j.semcdb.2020.08.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/31/2020] [Accepted: 08/01/2020] [Indexed: 12/26/2022]
Abstract
Microglia are universal sensors of alterations in CNS physiology. These cells integrate complex molecular signals and undergo comprehensive phenotypical remodeling to adapt inflammatory responses. In the last years, single-cell analyses have revealed that microglia exhibit diverse phenotypes during development, growth and disease. Emerging evidence suggests that such phenotype transitions are mediated by reprogramming of cell metabolism. Indeed, metabolic pathways are distinctively altered in activated microglia and are central nodes controlling microglial responses. Microglial lipid metabolism has been specifically involved in the control of microglial activation and effector functions, such as migration, phagocytosis and inflammatory signaling, and minor disturbances in microglial lipid handling associates with altered brain function in disorders featuring neuroinflammation. In this review, we explore new and relevant aspects of microglial metabolism in health and disease. We give special focus on how different branches of lipid metabolism, such as lipid sensing, synthesis and oxidation, integrate and control essential aspects of microglial biology, and how disturbances in these processes associate with aging and the pathogenesis of, for instance, multiple sclerosis and Alzheimer's disease. Finally, challenges and advances in microglial lipid research are discussed.
Collapse
Affiliation(s)
- Bruno Chausse
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany.
| | - Pamela A Kakimoto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000, São Paulo, Brazil
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany; Interdisciplinary Center for Neurosciences, University of Heidelberg, D-69120 Heidelberg, Germany
| |
Collapse
|
22
|
Chew H, Solomon VA, Fonteh AN. Involvement of Lipids in Alzheimer's Disease Pathology and Potential Therapies. Front Physiol 2020; 11:598. [PMID: 32581851 PMCID: PMC7296164 DOI: 10.3389/fphys.2020.00598] [Citation(s) in RCA: 156] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 05/14/2020] [Indexed: 12/15/2022] Open
Abstract
Lipids constitute the bulk of the dry mass of the brain and have been associated with healthy function as well as the most common pathological conditions of the brain. Demographic factors, genetics, and lifestyles are the major factors that influence lipid metabolism and are also the key components of lipid disruption in Alzheimer's disease (AD). Additionally, the most common genetic risk factor of AD, APOE ϵ4 genotype, is involved in lipid transport and metabolism. We propose that lipids are at the center of Alzheimer's disease pathology based on their involvement in the blood-brain barrier function, amyloid precursor protein (APP) processing, myelination, membrane remodeling, receptor signaling, inflammation, oxidation, and energy balance. Under healthy conditions, lipid homeostasis bestows a balanced cellular environment that enables the proper functioning of brain cells. However, under pathological conditions, dyshomeostasis of brain lipid composition can result in disturbed BBB, abnormal processing of APP, dysfunction in endocytosis/exocytosis/autophagocytosis, altered myelination, disturbed signaling, unbalanced energy metabolism, and enhanced inflammation. These lipid disturbances may contribute to abnormalities in brain function that are the hallmark of AD. The wide variance of lipid disturbances associated with brain function suggest that AD pathology may present as a complex interaction between several metabolic pathways that are augmented by risk factors such as age, genetics, and lifestyles. Herewith, we examine factors that influence brain lipid composition, review the association of lipids with all known facets of AD pathology, and offer pointers for potential therapies that target lipid pathways.
Collapse
Affiliation(s)
- Hannah Chew
- Huntington Medical Research Institutes, Pasadena, CA, United States
- University of California, Los Angeles, Los Angeles, CA, United States
| | | | - Alfred N. Fonteh
- Huntington Medical Research Institutes, Pasadena, CA, United States
| |
Collapse
|
23
|
Joffre C, Rey C, Layé S. N-3 Polyunsaturated Fatty Acids and the Resolution of Neuroinflammation. Front Pharmacol 2019; 10:1022. [PMID: 31607902 PMCID: PMC6755339 DOI: 10.3389/fphar.2019.01022] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 08/12/2019] [Indexed: 12/22/2022] Open
Abstract
In the past few decades, as a result of their anti-inflammatory properties, n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFAs), have gained greater importance in the regulation of inflammation, especially in the central nervous system (in this case known as neuroinflammation). If sustained, neuroinflammation is a common denominator of neurological disorders, including Alzheimer’s disease and major depression, and of aging. Hence, limiting neuroinflammation is a real strategy for neuroinflammatory disease therapy and treatment. Recent data show that n-3 LC-PUFAs exert anti-inflammatory properties in part through the synthesis of specialized pro-resolving mediators (SPMs) such as resolvins, maresins and protectins. These SPMs are crucially involved in the resolution of inflammation. They could be good candidates to resolve brain inflammation and to contribute to neuroprotective functions and could lead to novel therapeutics for brain inflammatory diseases. This review presents an overview 1) of brain n-3 LC-PUFAs as precursors of SPMs with an emphasis on the effect of n-3 PUFAs on neuroinflammation, 2) of the formation and action of SPMs in the brain and their biological roles, and the possible regulation of their synthesis by environmental factors such as inflammation and nutrition and, in particular, PUFA consumption.
Collapse
Affiliation(s)
- Corinne Joffre
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux, France.,Université de Bordeaux 2, Bordeaux, France
| | - Charlotte Rey
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux, France.,Université de Bordeaux 2, Bordeaux, France.,ITERG, Nutrition Health and Lipid Biochemistry Department, Canéjan, France
| | - Sophie Layé
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux, France.,Université de Bordeaux 2, Bordeaux, France
| |
Collapse
|
24
|
Leyrolle Q, Layé S, Nadjar A. Direct and indirect effects of lipids on microglia function. Neurosci Lett 2019; 708:134348. [PMID: 31238131 DOI: 10.1016/j.neulet.2019.134348] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 06/05/2019] [Accepted: 06/21/2019] [Indexed: 02/07/2023]
Abstract
Microglia are key players in brain function by maintaining brain homeostasis across lifetime. They participate to brain development and maturation through their ability to release neurotrophic factors, to remove immature synapses or unnecessary neural progenitors. They modulate neuronal activity in healthy adult brains and they also orchestrate the neuroinflammatory response in various pathophysiological contexts such as aging and neurodegenerative diseases. One of the main features of microglia is their high sensitivity to environmental factors, partly via the expression of a wide range of receptors. Recent data pinpoint that dietary fatty acids modulate microglia function. Both the quantity and the type of fatty acid are potent modulators of microglia physiology. The present review aims at dissecting the current knowledge on the direct and indirect mechanisms (focus on gut microbiota and hormones) through which fatty acids influence microglial physiology. We summarize main discoveries from in vitro and in vivo models on fatty acid-mediated microglial modulation. All these studies represent a promising field of research that could promote using nutrition as a novel therapeutic or preventive tool in diseases involving microglia dysfunctions.
Collapse
Affiliation(s)
- Q Leyrolle
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France
| | - S Layé
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France
| | - A Nadjar
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France.
| |
Collapse
|
25
|
El Hajj H, Savage JC, Bisht K, Parent M, Vallières L, Rivest S, Tremblay MÈ. Ultrastructural evidence of microglial heterogeneity in Alzheimer's disease amyloid pathology. J Neuroinflammation 2019; 16:87. [PMID: 30992040 PMCID: PMC6469225 DOI: 10.1186/s12974-019-1473-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 04/01/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is the most common neurodegenerative disease, characterized by the deposition of extracellular fibrillar amyloid β (fΑβ) and the intracellular accumulation of neurofibrillary tangles. As AD progresses, Aβ drives a robust and prolonged inflammatory response via its recognition by microglia, the brain's immune cells. Microglial reactivity to fAβ plaques may impair their normal surveillance duties, facilitating synaptic loss and neuronal death, as well as cognitive decline in AD. METHODS In the current study, we performed correlative light, transmission, and scanning electron microscopy to provide insights into microglial structural and functional heterogeneity. We analyzed microglial cell bodies and processes in areas containing fAβ plaques and neuronal dystrophy, dystrophy only, or appearing healthy, among the hippocampus CA1 of 14-month-old APPSwe-PS1Δe9 mice versus wild-type littermates. RESULTS Our quantitative analysis revealed that microglial cell bodies in the AD model mice were larger and displayed ultrastructural signs of cellular stress, especially nearby plaques. Microglial cell bodies and processes were overall less phagocytic in AD model mice. However, they contained increased fibrillar materials and non-empty inclusions proximal to plaques. Microglial cell bodies and processes in AD model mice also displayed reduced association with extracellular space pockets that contained debris. In addition, microglial processes in healthy subregions of AD model mice encircled synaptic elements more often compared with plaque-associated processes. These observations in mice were qualitatively replicated in post-mortem hippocampal samples from two patients with AD (Braak stage 5). CONCLUSION Together, our findings identify at the ultrastructural level distinct microglial transformations common to mouse and human in association with amyloid pathology.
Collapse
Affiliation(s)
- Hassan El Hajj
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, 2705, boulevard Laurier, T2-50, Quebec, QC G1V 4G2 Canada
| | - Julie C. Savage
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, 2705, boulevard Laurier, T2-50, Quebec, QC G1V 4G2 Canada
| | - Kanchan Bisht
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, 2705, boulevard Laurier, T2-50, Quebec, QC G1V 4G2 Canada
| | - Martin Parent
- Département de psychiatrie et de neurosciences, Faculté de médecine, Université Laval, Quebec, QC Canada
- CERVO Brain Research Center, Quebec, QC Canada
| | - Luc Vallières
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, 2705, boulevard Laurier, T2-50, Quebec, QC G1V 4G2 Canada
- Département de médecine moléculaire, Faculté de médecine, Université Laval, Quebec, QC Canada
| | - Serge Rivest
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, 2705, boulevard Laurier, T2-50, Quebec, QC G1V 4G2 Canada
- Département de médecine moléculaire, Faculté de médecine, Université Laval, Quebec, QC Canada
| | - Marie-Ève Tremblay
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, 2705, boulevard Laurier, T2-50, Quebec, QC G1V 4G2 Canada
- Département de médecine moléculaire, Faculté de médecine, Université Laval, Quebec, QC Canada
| |
Collapse
|
26
|
Distinct metabolic patterns during microglial remodeling by oleate and palmitate. Biosci Rep 2019; 39:BSR20190072. [PMID: 30867255 PMCID: PMC6449521 DOI: 10.1042/bsr20190072] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 02/20/2019] [Accepted: 03/06/2019] [Indexed: 12/13/2022] Open
Abstract
Microglial activation by oleate and palmitate differentially modulates brain inflammatory status. However, the metabolic reprogramming supporting these reactive phenotypes remains unknown. Employing real-time metabolic measurements and lipidomic analysis, we show that both fatty acids promote microglial oxidative metabolism, while lipopolysaccharide (LPS) enhances glycolytic rates. Interestingly, oleate treatment was followed by enrichment in storage lipids bound to polyunsaturated fatty acids (PUFA), in parallel with protection against oxidative imbalance. Palmitate, in turn, induced a distinct lipid distribution defined by PUFA linked to membrane phospholipids, which are more susceptible to lipid peroxidation and inflammatory signaling cascades. This distribution was mirrored by LPS treatment, which led to a strong pro-inflammatory phenotype in microglia. Thus, although both oleate and palmitate preserve mitochondrial function, a contrasting lipid distribution supports differences in fatty acid-induced neuroinflammation. These data reinforce the concept that reactive microglial profiles are achieved by stimulus-evoked remodeling in cell metabolism.
Collapse
|
27
|
Labrousse VF, Leyrolle Q, Amadieu C, Aubert A, Sere A, Coutureau E, Grégoire S, Bretillon L, Pallet V, Gressens P, Joffre C, Nadjar A, Layé S. Dietary omega-3 deficiency exacerbates inflammation and reveals spatial memory deficits in mice exposed to lipopolysaccharide during gestation. Brain Behav Immun 2018; 73:427-440. [PMID: 29879442 DOI: 10.1016/j.bbi.2018.06.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 05/21/2018] [Accepted: 06/03/2018] [Indexed: 01/03/2023] Open
Abstract
Maternal immune activation (MIA) is a common environmental insult on the developing brain and represents a risk factor for neurodevelopmental disorders. Animal models of in utero inflammation further revealed a causal link between maternal inflammatory activation during pregnancy and behavioural impairment relevant to neurodevelopmental disorders in the offspring. Accumulating evidence point out that proinflammatory cytokines produced both in the maternal and fetal compartments are responsible for social, cognitive and emotional behavioral deficits in the offspring. Polyunsaturated fatty acids (PUFAs) are essential fatty acids with potent immunomodulatory activities. PUFAs and their bioactive derivatives can promote or inhibit many aspects of the immune and inflammatory response. PUFAs of the n-3 series ('n-3 PUFAs', also known as omega-3) exhibit anti-inflammatory/pro-resolution properties and promote immune functions, while PUFAs of the n-6 series ('n-6 PUFAs' or omega-6) favor pro-inflammatory responses. The present study aimed at providing insight into the effects of n-3 PUFAs on the consequences of MIA on brain development. We hypothesized that a reduction in n-3 PUFAs exacerbates both maternal and fetal inflammatory responses to MIA and later-life defects in memory in the offspring. Based on a lipopolysaccharide (LPS) model of MIA (LPS injection at embryonic day 17), we showed that n-3 PUFA deficiency 1) alters fatty acid composition of the fetal and adult offspring brain; 2) exacerbates maternal and fetal inflammatory processes with no significant alteration of microglia phenotype, and 3) induces spatial memory deficits in the adult offspring. We also showed a strong negative correlation between brain content in n-3 PUFA and cytokine production in MIA-exposed fetuses. Overall, our study is the first to address the deleterious effects of n-3 PUFA deficiency on brain lipid composition, inflammation and memory performances in MIA-exposed animals and indicates that it should be considered as a potent environmental risk factor for the apparition of neurodevelopmental disorders.
Collapse
Affiliation(s)
- V F Labrousse
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France
| | - Q Leyrolle
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; PROTECT, INSERM, Université Paris Diderot, Sorbonne Paris Cité, F-75019 Paris, France
| | - C Amadieu
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France
| | - A Aubert
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France
| | - A Sere
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France
| | - E Coutureau
- Centre National de la Recherche Scientifique, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Uité Mixte de Recherche 5287, 33076 Bordeaux, France; Université de Bordeaux, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, 33076 Bordeaux, France
| | - S Grégoire
- Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, Dijon, France
| | - L Bretillon
- Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, Dijon, France
| | - V Pallet
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France
| | - P Gressens
- PROTECT, INSERM, Université Paris Diderot, Sorbonne Paris Cité, F-75019 Paris, France; Centre for the Developing Brain, Department of Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London SE1 7EH, United Kingdom
| | - C Joffre
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France
| | - A Nadjar
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France.
| | - S Layé
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France; Univ. Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076 Bordeaux, France.
| |
Collapse
|
28
|
Sun GY, Simonyi A, Fritsche KL, Chuang DY, Hannink M, Gu Z, Greenlief CM, Yao JK, Lee JC, Beversdorf DQ. Docosahexaenoic acid (DHA): An essential nutrient and a nutraceutical for brain health and diseases. Prostaglandins Leukot Essent Fatty Acids 2018; 136:3-13. [PMID: 28314621 PMCID: PMC9087135 DOI: 10.1016/j.plefa.2017.03.006] [Citation(s) in RCA: 143] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 03/06/2017] [Accepted: 03/09/2017] [Indexed: 01/01/2023]
Abstract
Docosahexaenoic acid (DHA), a polyunsaturated fatty acid (PUFA) enriched in phospholipids in the brain and retina, is known to play multi-functional roles in brain health and diseases. While arachidonic acid (AA) is released from membrane phospholipids by cytosolic phospholipase A2 (cPLA2), DHA is linked to action of the Ca2+-independent iPLA2. DHA undergoes enzymatic conversion by 15-lipoxygenase (Alox 15) to form oxylipins including resolvins and neuroprotectins, which are powerful lipid mediators. DHA can also undergo non-enzymatic conversion by reacting with oxygen free radicals (ROS), which cause the production of 4-hydoxyhexenal (4-HHE), an aldehyde derivative which can form adducts with DNA, proteins and lipids. In studies with both animal models and humans, there is evidence that inadequate intake of maternal n-3 PUFA may lead to aberrant development and function of the central nervous system (CNS). What is less certain is whether consumption of n-3 PUFA is important in maintaining brain health throughout one's life span. Evidence mostly from non-human studies suggests that DHA intake above normal nutritional requirements might modify the risk/course of a number of diseases of the brain. This concept has fueled much of the present interest in DHA research, in particular, in attempts to delineate mechanisms whereby DHA may serve as a nutraceutical and confer neuroprotective effects. Current studies have revealed ability for the oxylipins to regulation of cell redox homeostasis through the Nuclear factor (erythroid-derived 2)-like 2/Antioxidant response element (Nrf2/ARE) anti-oxidant pathway, and impact signaling pathways associated with neurotransmitters, and modulation of neuronal functions involving brain-derived neurotropic factor (BDNF). This review is aimed at describing recent studies elaborating these mechanisms with special regard to aging and Alzheimer's disease, autism spectrum disorder, schizophrenia, traumatic brain injury, and stroke.
Collapse
Affiliation(s)
- Grace Y Sun
- Biochemistry Department, University of Missouri, Columbia, MO, United States
| | - Agnes Simonyi
- Biochemistry Department, University of Missouri, Columbia, MO, United States
| | - Kevin L Fritsche
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, United States
| | - Dennis Y Chuang
- Department of Neurology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, OH, United States
| | - Mark Hannink
- Biochemistry Department, University of Missouri, Columbia, MO, United States
| | - Zezong Gu
- Department of Pathology and Anatomical Sciences, University of Missouri School of Medicine, Columbia, MO, United States
| | | | - Jeffrey K Yao
- Medical Research Service, VA Pittsburgh Healthcare System, and Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - James C Lee
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, United States
| | - David Q Beversdorf
- Department of Radiology, Neurology, and Psychological Sciences, and the Thompson Center, William and Nancy Thompson Endowed Chair in Radiology, University of Missouri School of Medicine, Columbia, MO, United States
| |
Collapse
|
29
|
Nadjar A. Role of metabolic programming in the modulation of microglia phagocytosis by lipids. Prostaglandins Leukot Essent Fatty Acids 2018; 135:63-73. [PMID: 30103935 DOI: 10.1016/j.plefa.2018.07.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 07/11/2018] [Accepted: 07/11/2018] [Indexed: 02/06/2023]
Abstract
Microglia phagocytosis is an essential process to maintain lifelong brain homeostasis and clear potential toxic factors from the neuropil. Microglia can engulf cells or part of cells through the expression of specific receptors at their surface and activation of downstream signaling pathways to engulf material. Microglia phagocytosis is finely regulated and is under the dependence of many factors, including environmental cues such as dietary lipids. Yet, the molecular mechanisms implicated are still largely unknown. The present publication is a 'hypothesis review', assessing the possibility that lipid-mediated modulation of phagocytosis occurs by affecting bioenergetic pathways within microglia. I assess our present knowledge and the elements that allow drawing such hypothesis. I also list some of the important gaps in the literature that need to be filled in. I also consider opportunities for future therapeutic target including nutritional interventions.
Collapse
Affiliation(s)
- A Nadjar
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France; University Bordeaux, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France.
| |
Collapse
|
30
|
Yang B, Li R, Michael Greenlief C, Fritsche KL, Gu Z, Cui J, Lee JC, Beversdorf DQ, Sun GY. Unveiling anti-oxidative and anti-inflammatory effects of docosahexaenoic acid and its lipid peroxidation product on lipopolysaccharide-stimulated BV-2 microglial cells. J Neuroinflammation 2018; 15:202. [PMID: 29986724 PMCID: PMC6038194 DOI: 10.1186/s12974-018-1232-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 06/20/2018] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Phospholipids in the central nervous system are enriched in n-3 and n-6 polyunsaturated fatty acids (PUFA), especially docosahexaenoic acid (DHA) and arachidonic acid (ARA). These PUFA can undergo enzymatic reactions to produce lipid mediators, as well as reaction with oxygen free radicals to produce 4-hydroxyhexenal (4-HHE) from DHA and 4-hydroxynonenal (4-HNE) from ARA. Recent studies demonstrated pleiotropic properties of these peroxidation products through interaction with oxidative and anti-oxidant response pathways. In this study, BV-2 microglial cells were used to investigate ability for DHA, 4-HHE, and 4-HNE to stimulate the anti-oxidant stress responses involving the nuclear factor erythroid-2-related factor 2 (Nrf2) pathway and synthesis of heme oxygenase (HO-1), as well as to mitigate lipopolysaccharide (LPS)-induced nitric oxide (NO), reactive oxygen species (ROS), and cytosolic phospholipase A2 (cPLA2). In addition, LC-MS/MS analysis was carried out to examine effects of exogenous DHA and LPS stimulation on endogenous 4-HHE and 4-HNE levels in BV-2 microglial cells. METHODS Effects of DHA, 4-HHE, and 4-HNE on LPS-induced NO production was determined using the Griess reagent. LPS-induced ROS production was measured using CM-H2DCFDA. Western blots were used to analyze expression of p-cPLA2, Nrf2, and HO-1. Cell viability and cytotoxicity were measured using the WST-1 assay, and cell protein concentrations were measured using the BCA protein assay kit. An ultra-high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was used to determine levels of free 4-HHE and 4-HNE in cells. RESULTS DHA (12.5-100 μM), 4-HHE (1.25-10 μM), and 4-HNE (1.25-10 μM) dose dependently suppressed LPS-induced production of NO, ROS, and as p-cPLA2 in BV-2 microglial cells. With the same concentrations, these compounds could enhance Nrf2 and HO-1 expression in these cells. Based on the estimated IC50 values, 4-HHE and 4-HNE were five- to tenfold more potent than DHA in inhibiting LPS-induced NO, ROS, and p-cPLA2. LC-MS/MS analysis indicated ability for DHA (10-50 μM) to increase levels of 4-HHE and attenuate levels of 4-HNE in BV-2 microglial cells. Stimulation of cells with LPS caused an increase in 4-HNE which could be abrogated by cPLA2 inhibitor. In contrast, bromoenol lactone (BEL), a specific inhibitor for the Ca2+-independent phospholipase A2 (iPLA2), could only partially suppress levels of 4-HHE induced by DHA or DHA + LPS. CONCLUSIONS This study demonstrated the ability of DHA and its lipid peroxidation products, namely, 4-HHE and 4-HNE at 1.25-10 μM, to enhance Nrf2/HO-1 and mitigate LPS-induced NO, ROS, and p-cPLA2 in BV-2 microglial cells. In addition, LC-MS/MS analysis of the levels of 4-HHE and 4-HNE in microglial cells demonstrates that increases in production of 4-HHE from DHA and 4-HNE from LPS are mediated by different mechanisms.
Collapse
Affiliation(s)
- Bo Yang
- Chemistry Department, University of Missouri, Columbia, MO, USA
| | - Runting Li
- Biochemistry Department, University of Missouri, 117 Schweitzer Hall, Columbia, MO, 65211, USA
| | | | - Kevin L Fritsche
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA
| | - Zezong Gu
- Department of Pathology and Anatomical Sciences, University of Missouri, Columbia, MO, USA
| | - Jiankun Cui
- Department of Pathology and Anatomical Sciences, University of Missouri, Columbia, MO, USA
| | - James C Lee
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
| | - David Q Beversdorf
- Departments of Radiology, Neurology and Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Grace Y Sun
- Biochemistry Department, University of Missouri, 117 Schweitzer Hall, Columbia, MO, 65211, USA. .,Department of Pathology and Anatomical Sciences, University of Missouri, Columbia, MO, USA.
| |
Collapse
|
31
|
Rey C, Nadjar A, Joffre F, Amadieu C, Aubert A, Vaysse C, Pallet V, Layé S, Joffre C. Maternal n-3 polyunsaturated fatty acid dietary supply modulates microglia lipid content in the offspring. Prostaglandins Leukot Essent Fatty Acids 2018; 133:1-7. [PMID: 29789127 DOI: 10.1016/j.plefa.2018.04.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/20/2018] [Accepted: 04/20/2018] [Indexed: 12/12/2022]
Abstract
The brain is highly enriched in long chain polyunsaturated fatty acids (LC-PUFAs) that are esterified into phospholipids, the major components of cell membranes. They accumulate during the perinatal period when the brain is rapidly developing. Hence, the levels of LC-PUFAs in the brains of the offspring greatly depend on maternal dietary intake. Perinatal n-3 PUFA consumption has been suggested to modulate the activity of microglial cells, the brain's innate immune cells which contribute to the shaping of neuronal network during development. However, the impact of maternal n-3 PUFA intake on microglial lipid composition in the offspring has never been studied. To investigate the impact of maternal dietary n-3 PUFA supply on microglia lipid composition, pregnant mice were fed with n-3 PUFA deficient, n-3 PUFA balanced or n-3 PUFA supplemented diets during gestation and lactation. At weaning, microglia were isolated from the pup's brains to analyze their fatty acid composition and phospholipid class levels. We here report that post-natal microglial cells displayed a distinctive lipid profile as they contained high levels of eicosapentaenoic acid (EPA), more EPA than docosahexaenoic acid (DHA) and large amount of phosphatidylinositol (PI) / phosphatidylserine (PS). Maternal n-3 PUFA supply increased DHA levels and decreased n-6 docosapentaenoic acid (DPA) levels whereas the PI/PS membrane content was inversely correlated to the quantity of PUFAs in the diet. These results raise the possibility of modulating microglial lipid profile and their subsequent activity in the developing brain.
Collapse
Affiliation(s)
- Charlotte Rey
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France; Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France; ITERG, Institut des corps gras, Canéjan 33610, France
| | - Agnès Nadjar
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France; Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France
| | | | - Camille Amadieu
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France; Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France
| | - Agnès Aubert
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France; Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France
| | - Carole Vaysse
- ITERG, Institut des corps gras, Canéjan 33610, France
| | - Véronique Pallet
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France; Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France
| | - Sophie Layé
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France; Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France
| | - Corinne Joffre
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France; Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux 33076, France.
| |
Collapse
|
32
|
Savage JC, Picard K, González-Ibáñez F, Tremblay MÈ. A Brief History of Microglial Ultrastructure: Distinctive Features, Phenotypes, and Functions Discovered Over the Past 60 Years by Electron Microscopy. Front Immunol 2018; 9:803. [PMID: 29922276 PMCID: PMC5996933 DOI: 10.3389/fimmu.2018.00803] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/03/2018] [Indexed: 01/01/2023] Open
Abstract
The first electron microscope was constructed in 1931. Several decades later, techniques were developed to allow the first ultrastructural analysis of microglia by transmission electron microscopy (EM). In the 50 years that followed, important roles of microglia have been identified, specifically due to the ultrastructural resolution currently available only with EM. In particular, the addition of electron-dense staining using immunohistochemical EM methods has allowed the identification of microglial cell bodies, as well as processes, which are difficult to recognize in EM, and to uncover their complex interactions with neurons and synapses. The ability to recognize neuronal, astrocytic, and oligodendrocytic compartments in the neuropil without any staining is another invaluable advantage of EM over light microscopy for studying intimate cell-cell contacts. The technique has been essential in defining microglial interactions with neurons and synapses, thus providing, among other discoveries, important insights into their roles in synaptic stripping and pruning via phagocytosis of extraneous synapses. Recent technological advances in EM including serial block-face imaging and focused-ion beam scanning EM have also facilitated automated acquisition of large tissue volumes required to reconstruct neuronal circuits in 3D at nanometer-resolution. These cutting-edge techniques which are now becoming increasingly available will further revolutionize the study of microglia across stages of the lifespan, brain regions, and contexts of health and disease. In this mini-review, we will focus on defining the distinctive ultrastructural features of microglia and the unique insights into their function that were provided by EM.
Collapse
Affiliation(s)
- Julie C. Savage
- Axe neurosciences, Centre de Recherche du CHU de Québec – Université Laval, Québec City, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
| | - Katherine Picard
- Axe neurosciences, Centre de Recherche du CHU de Québec – Université Laval, Québec City, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
| | - Fernando González-Ibáñez
- Axe neurosciences, Centre de Recherche du CHU de Québec – Université Laval, Québec City, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
| | - Marie-Ève Tremblay
- Axe neurosciences, Centre de Recherche du CHU de Québec – Université Laval, Québec City, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
| |
Collapse
|
33
|
Layé S, Nadjar A, Joffre C, Bazinet RP. Anti-Inflammatory Effects of Omega-3 Fatty Acids in the Brain: Physiological Mechanisms and Relevance to Pharmacology. Pharmacol Rev 2017; 70:12-38. [PMID: 29217656 DOI: 10.1124/pr.117.014092] [Citation(s) in RCA: 233] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Accepted: 09/05/2017] [Indexed: 12/17/2022] Open
Abstract
Classically, polyunsaturated fatty acids (PUFA) were largely thought to be relatively inert structural components of brain, largely important for the formation of cellular membranes. Over the past 10 years, a host of bioactive lipid mediators that are enzymatically derived from arachidonic acid, the main n-6 PUFA, and docosahexaenoic acid, the main n-3 PUFA in the brain, known to regulate peripheral immune function, have been detected in the brain and shown to regulate microglia activation. Recent advances have focused on how PUFA regulate the molecular signaling of microglia, especially in the context of neuroinflammation and behavior. Several active drugs regulate brain lipid signaling and provide proof of concept for targeting the brain. Because brain lipid metabolism relies on a complex integration of diet, peripheral metabolism, including the liver and blood, which supply the brain with PUFAs that can be altered by genetics, sex, and aging, there are many pathways that can be disrupted, leading to altered brain lipid homeostasis. Brain lipid signaling pathways are altered in neurologic disorders and may be viable targets for the development of novel therapeutics. In this study, we discuss in particular how n-3 PUFAs and their metabolites regulate microglia phenotype and function to exert their anti-inflammatory and proresolving activities in the brain.
Collapse
Affiliation(s)
- Sophie Layé
- Institut National pour la Recherche Agronomique and Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux, France (S.L., A.N., C.J.); and Department of Nutritional Sciences, University of Toronto, Ontario, Canada (R.P.B.)
| | - Agnès Nadjar
- Institut National pour la Recherche Agronomique and Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux, France (S.L., A.N., C.J.); and Department of Nutritional Sciences, University of Toronto, Ontario, Canada (R.P.B.)
| | - Corinne Joffre
- Institut National pour la Recherche Agronomique and Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux, France (S.L., A.N., C.J.); and Department of Nutritional Sciences, University of Toronto, Ontario, Canada (R.P.B.)
| | - Richard P Bazinet
- Institut National pour la Recherche Agronomique and Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, Bordeaux, France (S.L., A.N., C.J.); and Department of Nutritional Sciences, University of Toronto, Ontario, Canada (R.P.B.)
| |
Collapse
|
34
|
Fourrier C, Remus-Borel J, Greenhalgh AD, Guichardant M, Bernoud-Hubac N, Lagarde M, Joffre C, Layé S. Docosahexaenoic acid-containing choline phospholipid modulates LPS-induced neuroinflammation in vivo and in microglia in vitro. J Neuroinflammation 2017; 14:170. [PMID: 28838312 PMCID: PMC5571638 DOI: 10.1186/s12974-017-0939-x] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 08/09/2017] [Indexed: 12/27/2022] Open
Abstract
Background Neuroinflammatory processes are considered a double-edged sword, having both protective and detrimental effects in the brain. Microglia, the brain’s resident innate immune cells, are a key component of neuroinflammatory response. There is a growing interest in developing drugs to target microglia and control neuroinflammatory processes. In this regard, docosahexaenoic acid (DHA), the brain’s n-3 polyunsaturated fatty acid, is a promising molecule to regulate pro-inflammatory microglia and cytokine production. Several works reported that the bioavailability of DHA to the brain is higher when DHA is acylated to phospholipid. In this work, we analyzed the anti-inflammatory activity of DHA-phospholipid, either acetylated at the sn-1 position (AceDoPC, a stable form thought to have superior access to the brain) or acylated with palmitic acid at the sn-1 position (PC-DHA) using a lipopolysaccharide (LPS)-induced neuroinflammation model both in vitro and in vivo. Methods In vivo, adult C57Bl6/J mice were injected intravenously (i.v.) with either AceDoPC or PC-DHA 24 h prior to LPS (i.p.). For in vitro studies, immortalized murine microglia cells BV-2 were co-incubated with DHA forms and LPS. AceDoPC and PC-DHA effect on brain or BV-2 PUFA content was assessed by gas chromatography. LPS-induced pro-inflammatory cytokines interleukin IL-1β, IL-6, and tumor necrosis factor (TNF) α production were measured by quantitative PCR (qPCR) or multiplex. IL-6 receptors and associated signaling pathway STAT3 were assessed by FACS analysis and western-blot in vitro. Results In vivo, a single injection of AceDoPC or PC-DHA decreased LPS-induced IL-6 production in the hippocampus of mice. This effect could be linked to their direct effect on microglia, as revealed in vitro. In addition, AceDoPC or PC-DHA reduced IL-6 receptor while only AceDoPC decreased IL-6-induced STAT3 phosphorylation. Conclusions These results highlight the potency of administered DHA—acetylated to phospholipids—to rapidly regulate LPS-induced neuroinflammatory processes through their effect on microglia. In particular, both IL-6 production and signaling are targeted by AceDoPC in microglia.
Collapse
Affiliation(s)
- Célia Fourrier
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France.,Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France
| | - Julie Remus-Borel
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France.,Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France
| | - Andrew D Greenhalgh
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France.,Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France
| | - Michel Guichardant
- CarMeN laboratory, INSERM UMR 1060, INRA UMR 1397, IMBL, INSA-Lyon, University of Lyon, Lyon, France
| | - Nathalie Bernoud-Hubac
- CarMeN laboratory, INSERM UMR 1060, INRA UMR 1397, IMBL, INSA-Lyon, University of Lyon, Lyon, France
| | - Michel Lagarde
- CarMeN laboratory, INSERM UMR 1060, INRA UMR 1397, IMBL, INSA-Lyon, University of Lyon, Lyon, France
| | - Corinne Joffre
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France. .,Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France.
| | - Sophie Layé
- INRA, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France. .,Bordeaux University, Nutrition et Neurobiologie Intégrée, UMR 1286, 33076, Bordeaux, France.
| |
Collapse
|
35
|
Chen X, Wu S, Chen C, Xie B, Fang Z, Hu W, Chen J, Fu H, He H. Omega-3 polyunsaturated fatty acid supplementation attenuates microglial-induced inflammation by inhibiting the HMGB1/TLR4/NF-κB pathway following experimental traumatic brain injury. J Neuroinflammation 2017; 14:143. [PMID: 28738820 PMCID: PMC5525354 DOI: 10.1186/s12974-017-0917-3] [Citation(s) in RCA: 170] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 07/11/2017] [Indexed: 01/12/2023] Open
Abstract
Background Microglial activation and the subsequent inflammatory response in the central nervous system play important roles in secondary damage after traumatic brain injury (TBI). High-mobility group box 1 (HMGB1) protein, an important mediator in late inflammatory responses, interacts with transmembrane receptor for advanced glycation end products (RAGE) and toll-like receptors (TLRs) to activate downstream signaling pathways, such as the nuclear factor (NF)-κB signaling pathway, leading to a cascade amplification of inflammatory responses, which are related to neuronal damage after TBI. Omega-3 polyunsaturated fatty acid (ω-3 PUFA) is a commonly used clinical immunonutrient, which has antioxidative and anti-inflammatory effects. However, the effects of ω-3 PUFA on HMGB1 expression and HMGB1-mediated activation of the TLR4/NF-κB signaling pathway are not clear. Methods The Feeney DM TBI model was adopted to induce brain injury in rats. Modified neurological severity scores, brain water content, and Nissl staining were employed to determine the neuroprotective effects of ω-3 PUFA supplementation. Assessment of microglial activation in lesioned sites and protein markers for proinflammatory, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, interferon (IFN)-γ, and HMGB1 were used to evaluate neuroinflammatory responses and anti-inflammation effects of ω-3 PUFA supplementation. Immunofluorescent staining and western blot analysis were used to detect HMGB1 nuclear translocation, secretion, and HMGB1-mediated activation of the TLR4/NF-κB signaling pathway to evaluate the effects of ω-3 PUFA supplementation and gain further insight into the mechanisms underlying the development of the neuroinflammatory response after TBI. Results It was found that ω-3 PUFA supplementation inhibited TBI-induced microglial activation and expression of inflammatory factors (TNF-α, IL-1β, IL-6, and IFN-γ), reduced brain edema, decreased neuronal apoptosis, and improved neurological functions after TBI. We further demonstrated that ω-3 PUFA supplementation inhibited HMGB1 nuclear translocation and secretion and decreased expression of HMGB1 in neurons and microglia in the lesioned areas. Moreover, ω-3 PUFA supplementation inhibited microglial activation and the subsequent inflammatory response by regulating HMGB1 and the TLR4/NF-κB signaling pathway. Conclusions The results of this study suggest that microglial activation and the subsequent neuroinflammatory response as well as the related HMGB1/TLR4/NF-κB signaling pathway play essential roles in secondary injury after TBI. Furthermore, ω-3 PUFA supplementation inhibited TBI-induced microglial activation and the subsequent inflammatory response by regulating HMGB1 nuclear translocation and secretion and also HMGB1-mediated activation of the TLR4/NF-κB signaling pathway, leading to neuroprotective effects.
Collapse
Affiliation(s)
- Xiangrong Chen
- Department of Neurosurgery, the Second Affiliated Hospital, Fujian Medical University, Quanzhou, 362000, Fujian Province, China
| | - Shukai Wu
- Department of Neurosurgery, the Second Affiliated Hospital, Fujian Medical University, Quanzhou, 362000, Fujian Province, China
| | - Chunnuan Chen
- Department of Neurology, the Second Affiliated Hospital, Fujian Medical University, Quanzhou, 362000, Fujian Province, China
| | - Baoyuan Xie
- Department of Neurosurgery, the Second Affiliated Hospital, Fujian Medical University, Quanzhou, 362000, Fujian Province, China
| | - Zhongning Fang
- Department of Neurosurgery, the Second Affiliated Hospital, Fujian Medical University, Quanzhou, 362000, Fujian Province, China
| | - Weipeng Hu
- Department of Neurosurgery, the Second Affiliated Hospital, Fujian Medical University, Quanzhou, 362000, Fujian Province, China
| | - Junyan Chen
- Department of Neurosurgery, the Second Affiliated Hospital, Fujian Medical University, Quanzhou, 362000, Fujian Province, China
| | - Huangde Fu
- Department of Neurosurgery, Affiliated Hospital of YouJiang Medical University for Nationalities, Baise, 533000, Guangxi Province, China.
| | - Hefan He
- Department of Anesthesia, the Second Affiliated Hospital, Fujian Medical University, Quanzhou, 362000, Fujian Province, China.
| |
Collapse
|
36
|
The Role of Lipid Bodies in the Microglial Aging Process and Related Diseases. Neurochem Res 2017; 42:3140-3148. [PMID: 28699057 DOI: 10.1007/s11064-017-2351-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 02/22/2017] [Accepted: 07/07/2017] [Indexed: 01/08/2023]
Abstract
Lipid bodies (LBs) have long been considered to be organelles merely for the storage of neutral lipids. However, recent studies have shown the significance of LBs in signal transduction, especially in glial cells, including microglia. Microglial cells are the resident mononuclear phagocytes in the central nervous system and have a close relationship with the aging process and neurodegenerative diseases. Evidence suggests that LBs accumulate and are remodeled during the aging process and the development of neuroinflammatory conditions. However, the mechanisms underlying the formation of LBs under these conditions and the mechanism by which LB remodeling influences the progression of neurodegeneration remain to be clarified. In this review, we have summarized the findings from recent studies with the aim of further elucidating these issues.
Collapse
|
37
|
Paolicelli RC, Ferretti MT. Function and Dysfunction of Microglia during Brain Development: Consequences for Synapses and Neural Circuits. Front Synaptic Neurosci 2017; 9:9. [PMID: 28539882 PMCID: PMC5423952 DOI: 10.3389/fnsyn.2017.00009] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 04/27/2017] [Indexed: 01/02/2023] Open
Abstract
Many diverse factors, ranging from stress to infections, can perturb brain homeostasis and alter the physiological activity of microglia, the immune cells of the central nervous system. Microglia play critical roles in the process of synaptic maturation and brain wiring during development. Any perturbation affecting microglial physiological function during critical developmental periods could result in defective maturation of synaptic circuits. In this review, we critically appraise the recent literature on the alterations of microglial activity induced by environmental and genetic factors occurring at pre- and early post-natal stages. Furthermore, we discuss the long-lasting consequences of early-life microglial perturbation on synaptic function and on vulnerability to neurodevelopmental and psychiatric disorders.
Collapse
Affiliation(s)
- Rosa C Paolicelli
- IREM, Institute for Regenerative Medicine, University of ZurichZürich, Switzerland.,ZNZ Neuroscience Center ZurichZürich, Switzerland
| | - Maria T Ferretti
- IREM, Institute for Regenerative Medicine, University of ZurichZürich, Switzerland.,ZNZ Neuroscience Center ZurichZürich, Switzerland
| |
Collapse
|
38
|
Churchward MA, Tchir DR, Todd KG. Microglial Function during Glucose Deprivation: Inflammatory and Neuropsychiatric Implications. Mol Neurobiol 2017; 55:1477-1487. [PMID: 28176274 PMCID: PMC5820372 DOI: 10.1007/s12035-017-0422-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Accepted: 01/25/2017] [Indexed: 12/23/2022]
Abstract
Inflammation is increasingly recognized as a contributor to the pathophysiology of neuropsychiatric disorders, including depression, anxiety disorders and autism, though the factors leading to contextually inappropriate or sustained inflammation in pathological conditions are yet to be elucidated. Microglia, as the key mediators of inflammation in the CNS, serve as likely candidates in initiating pathological inflammation and as an ideal point of therapeutic intervention. Glucose deprivation, as a component of the pathophysiology of ischemia or occurring transiently in diabetes, may serve to modify microglial function contributing to inflammatory injury. To this end, primary microglia were cultured from postnatal rat brain and subject to glucose deprivation in vitro. Microglia were characterized for their proliferation, phagocytic function and secretion of inflammatory factors, and tested for their capacity to respond to a potent inflammatory stimulus. In the absence of glucose, microglia remained capable of proliferation, phagocytosis and inflammatory activation and showed increased release of inflammatory factors after presentation of an inflammatory stimulus. Glucose-deprived microglia demonstrated increased phagocytic activity and decreased accumulation of lipids in lipid droplets over a 48-h timecourse, suggesting they may use scavenged lipids as a key alternate energy source during metabolic stress. In the present manuscript, we present novel findings that glucose deprivation may sensitize microglial release of inflammatory mediators and prime microglial functions for both survival and inflammatory roles, which may contribute to psychiatric comorbidities of ischemia, diabetes and/or metabolic disorder.
Collapse
Affiliation(s)
- Matthew A Churchward
- Neurochemical Research Unit, Department of Psychiatry, University of Alberta, 116th St and 85th Ave NW, Edmonton, AB T6G2R3, Canada
| | - Devan R Tchir
- Neurochemical Research Unit, Department of Psychiatry, University of Alberta, 116th St and 85th Ave NW, Edmonton, AB T6G2R3, Canada
| | - Kathryn G Todd
- Neurochemical Research Unit, Department of Psychiatry, University of Alberta, 116th St and 85th Ave NW, Edmonton, AB T6G2R3, Canada. .,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2R3, Canada.
| |
Collapse
|
39
|
Jiang X, Pu H, Hu X, Wei Z, Hong D, Zhang W, Gao Y, Chen J, Shi Y. A Post-stroke Therapeutic Regimen with Omega-3 Polyunsaturated Fatty Acids that Promotes White Matter Integrity and Beneficial Microglial Responses after Cerebral Ischemia. Transl Stroke Res 2016; 7:548-561. [PMID: 27714669 DOI: 10.1007/s12975-016-0502-6] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 09/24/2016] [Accepted: 09/27/2016] [Indexed: 02/03/2023]
Abstract
White matter injury induced by ischemic stroke elicits sensorimotor impairments, which can be further deteriorated by persistent proinflammatory responses. We previously reported that delayed and repeated treatments with omega-3 polyunsaturated fatty acids (n-3 PUFAs) improve spatial cognitive functions and hippocampal integrity after ischemic stroke. In the present study, we report a post-stroke n-3 PUFA therapeutic regimen that not only confers protection against neuronal loss in the gray matter but also promotes white matter integrity. Beginning 2 h after 60 min of middle cerebral artery occlusion (MCAO), mice were randomly assigned to receive intraperitoneal docosahexaenoic acid (DHA) injections (10 mg/kg, daily for 14 days), alone or in combination with dietary fish oil (FO) supplements starting 5 days after MCAO. Sensorimotor functions, gray and white matter injury, and microglial responses were examined up to 28 days after MCAO. Our results showed that DHA and FO combined treatment-facilitated long-term sensorimotor recovery and demonstrated greater beneficial effect than DHA injections alone. Mechanistically, n-3 PUFAs not only offered direct protection on white matter components, such as oligodendrocytes, but also potentiated microglial M2 polarization, which may be important for white matter repair. Notably, the improved white matter integrity and increased M2 microglia were strongly linked to the mitigation of sensorimotor deficits after stroke upon n-3 PUFA treatments. Together, our results suggest that post-stroke DHA injections in combination with FO dietary supplement benefit white matter restoration and microglial responses, thereby dictating long-term functional improvements.
Collapse
Affiliation(s)
- Xiaoyan Jiang
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai, 200032, China.,Pittsburgh Institute of Brain Disorders and Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Hongjian Pu
- Pittsburgh Institute of Brain Disorders and Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Xiaoming Hu
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai, 200032, China.,Pittsburgh Institute of Brain Disorders and Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA.,Geriatric Research, Educational and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA, 15261, USA
| | - Zhishuo Wei
- Pittsburgh Institute of Brain Disorders and Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Dandan Hong
- Pittsburgh Institute of Brain Disorders and Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Wenting Zhang
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Yanqin Gao
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai, 200032, China.,Pittsburgh Institute of Brain Disorders and Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Jun Chen
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai, 200032, China. .,Pittsburgh Institute of Brain Disorders and Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA. .,Geriatric Research, Educational and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA, 15261, USA.
| | - Yejie Shi
- Pittsburgh Institute of Brain Disorders and Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA. .,Geriatric Research, Educational and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA, 15261, USA.
| |
Collapse
|
40
|
Maysinger D, Zhang I. Nutritional and Nanotechnological Modulators of Microglia. Front Immunol 2016; 7:270. [PMID: 27471505 PMCID: PMC4945637 DOI: 10.3389/fimmu.2016.00270] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 06/27/2016] [Indexed: 12/11/2022] Open
Abstract
Microglia are the essential responders to alimentary, pharmacological, and nanotechnological immunomodulators. These neural cells play multiple roles as surveyors, sculptors, and guardians of essential parts of complex neural circuitries. Microglia can play dual roles in the central nervous system; they can be deleterious and/or protective. The immunomodulatory effects of alimentary components, gut microbiota, and nanotechnological products have been investigated in microglia at the single-cell level and in vivo using intravital imaging approaches, and different biochemical assays. This review highlights some of the emerging questions and topics from studies involving alimentation, microbiota, nanotechnological products, and associated problems in this area of research. Some of the advantages and limitations of in vitro and in vivo models used to study the neuromodulatory effects of these factors, as well as the merits and pitfalls of intravital imaging modalities employed are presented.
Collapse
Affiliation(s)
- Dusica Maysinger
- Department of Pharmacology and Therapeutics, McGill University , Montreal, QC , Canada
| | - Issan Zhang
- Department of Pharmacology and Therapeutics, McGill University , Montreal, QC , Canada
| |
Collapse
|