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Pramanik S, Devi M H, Chakrabarty S, Paylar B, Pradhan A, Thaker M, Ayyadhury S, Manavalan A, Olsson PE, Pramanik G, Heese K. Microglia signaling in health and disease - Implications in sex-specific brain development and plasticity. Neurosci Biobehav Rev 2024; 165:105834. [PMID: 39084583 DOI: 10.1016/j.neubiorev.2024.105834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Revised: 07/21/2024] [Accepted: 07/27/2024] [Indexed: 08/02/2024]
Abstract
Microglia, the intrinsic neuroimmune cells residing in the central nervous system (CNS), exert a pivotal influence on brain development, homeostasis, and functionality, encompassing critical roles during both aging and pathological states. Recent advancements in comprehending brain plasticity and functions have spotlighted conspicuous variances between male and female brains, notably in neurogenesis, neuronal myelination, axon fasciculation, and synaptogenesis. Nevertheless, the precise impact of microglia on sex-specific brain cell plasticity, sculpting diverse neural network architectures and circuits, remains largely unexplored. This article seeks to unravel the present understanding of microglial involvement in brain development, plasticity, and function, with a specific emphasis on microglial signaling in brain sex polymorphism. Commencing with an overview of microglia in the CNS and their associated signaling cascades, we subsequently probe recent revelations regarding molecular signaling by microglia in sex-dependent brain developmental plasticity, functions, and diseases. Notably, C-X3-C motif chemokine receptor 1 (CX3CR1), triggering receptors expressed on myeloid cells 2 (TREM2), calcium (Ca2+), and apolipoprotein E (APOE) emerge as molecular candidates significantly contributing to sex-dependent brain development and plasticity. In conclusion, we address burgeoning inquiries surrounding microglia's pivotal role in the functional diversity of developing and aging brains, contemplating their potential implications for gender-tailored therapeutic strategies in neurodegenerative diseases.
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Affiliation(s)
- Subrata Pramanik
- Jyoti and Bhupat Mehta School of Health Sciences and Technology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
| | - Harini Devi M
- Jyoti and Bhupat Mehta School of Health Sciences and Technology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Saswata Chakrabarty
- Jyoti and Bhupat Mehta School of Health Sciences and Technology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Berkay Paylar
- Biology, The Life Science Center, School of Science and Technology, Örebro University, Örebro 70182, Sweden
| | - Ajay Pradhan
- Biology, The Life Science Center, School of Science and Technology, Örebro University, Örebro 70182, Sweden
| | - Manisha Thaker
- Eurofins Lancaster Laboratories, Inc., 2425 New Holland Pike, Lancaster, PA 17601, USA
| | - Shamini Ayyadhury
- The Donnelly Centre, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | - Arulmani Manavalan
- Department of Cariology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu 600077, India
| | - Per-Erik Olsson
- Biology, The Life Science Center, School of Science and Technology, Örebro University, Örebro 70182, Sweden
| | - Gopal Pramanik
- Department of Pharmaceutical Sciences and Technology, Birla Institute of Technology, Mesra, Ranchi, Jharkhand 835215, India.
| | - Klaus Heese
- Graduate School of Biomedical Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133791, the Republic of Korea.
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2
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Dai CL, Liu F, Iqbal K, Gong CX. Gut Microbiota and Immunotherapy for Alzheimer's Disease. Int J Mol Sci 2022; 23:15230. [PMID: 36499564 PMCID: PMC9741026 DOI: 10.3390/ijms232315230] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/08/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder that eventually leads to dementia and death of the patient. Currently, no effective treatment is available that can slow or halt the progression of the disease. The gut microbiota can modulate the host immune system in the peripheral and central nervous system through the microbiota-gut-brain axis. Growing evidence indicates that gut microbiota dysbiosis plays an important role in the pathogenesis of AD, and modulation of the gut microbiota may represent a new avenue for treating AD. Immunotherapy targeting Aβ and tau has emerged as the most promising disease-modifying therapy for the treatment of AD. However, the underlying mechanism of AD immunotherapy is not known. Importantly, preclinical and clinical studies have highlighted that the gut microbiota exerts a major influence on the efficacy of cancer immunotherapy. However, the role of the gut microbiota in AD immunotherapy has not been explored. We found that immunotherapy targeting tau can modulate the gut microbiota in an AD mouse model. In this article, we focused on the crosstalk between the gut microbiota, immunity, and AD immunotherapy. We speculate that modulation of the gut microbiota induced by AD immunotherapy may partially underlie the efficacy of the treatment.
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Affiliation(s)
| | | | | | - Cheng-Xin Gong
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, NY 10314, USA
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3
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Miyata S. Glial functions in the blood-brain communication at the circumventricular organs. Front Neurosci 2022; 16:991779. [PMID: 36278020 PMCID: PMC9583022 DOI: 10.3389/fnins.2022.991779] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
The circumventricular organs (CVOs) are located around the brain ventricles, lack a blood-brain barrier (BBB) and sense blood-derived molecules. This review discusses recent advances in the importance of CVO functions, especially glial cells transferring periphery inflammation signals to the brain. The CVOs show size-limited vascular permeability, allowing the passage of molecules with molecular weight <10,000. This indicates that the lack of an endothelial cell barrier does not mean the free movement of blood-derived molecules into the CVO parenchyma. Astrocytes and tanycytes constitute a dense barrier at the distal CVO subdivision, preventing the free diffusion of blood-derived molecules into neighboring brain regions. Tanycytes in the CVOs mediate communication between cerebrospinal fluid and brain parenchyma via transcytosis. Microglia and macrophages of the CVOs are essential for transmitting peripheral information to other brain regions via toll-like receptor 2 (TLR2). Inhibition of TLR2 signaling or depletion of microglia and macrophages in the brain eliminates TLR2-dependent inflammatory responses. In contrast to TLR2, astrocytes and tanycytes in the CVOs of the brain are crucial for initiating lipopolysaccharide (LPS)-induced inflammatory responses via TLR4. Depletion of microglia and macrophages augments LPS-induced fever and chronic sickness responses. Microglia and macrophages in the CVOs are continuously activated, even under normal physiological conditions, as they exhibit activated morphology and express the M1/M2 marker proteins. Moreover, the microglial proliferation occurs in various regions, such as the hypothalamus, medulla oblongata, and telencephalon, with a marked increase in the CVOs, due to low-dose LPS administration, and after high-dose LPS administration, proliferation is seen in most brain regions, except for the cerebral cortex and hippocampus. A transient increase in the microglial population is beneficial during LPS-induced inflammation for attenuating sickness response. Transient receptor potential receptor vanilloid 1 expressed in astrocytes and tanycytes of the CVOs is responsible for thermoregulation upon exposure to a warm environment less than 37°C. Alternatively, Nax expressed in astrocytes and tanycytes of the CVOs is crucial for maintaining body fluid homeostasis. Thus, recent findings indicate that glial cells in the brain CVOs are essential for initiating neuroinflammatory responses and maintaining body fluid and thermal homeostasis.
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4
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Alimohammadi M, Makaremi S, Rahimi A, Asghariazar V, Taghadosi M, Safarzadeh E. DNA methylation changes and inflammaging in aging-associated diseases. Epigenomics 2022; 14:965-986. [PMID: 36043685 DOI: 10.2217/epi-2022-0143] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aging as an inevitable phenomenon is associated with pervasive changes in physiological functions. There is a relationship between aging and the increase of several chronic diseases. Most age-related disorders are accompanied by an underlying chronic inflammatory state, as demonstrated by local infiltration of inflammatory cells and greater levels of proinflammatory cytokines in the bloodstream. Within inflammaging, many epigenetic events, especially DNA methylation, change. During the aging process, due to aberrations of DNA methylation, biological processes are disrupted, leading to the emergence or progression of a variety of human diseases, including cancer, neurodegenerative disorders, cardiovascular disease and diabetes. The focus of this review is on DNA methylation, which is involved in inflammaging-related activities, and how its dysregulation leads to human disorders.
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Affiliation(s)
- Mina Alimohammadi
- Department of Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, 1983969411, Iran
| | - Shima Makaremi
- School of Medicine & Allied Medical Sciences, Ardabil University of Medical Sciences, Ardabil, 5618985991, Iran
| | - Ali Rahimi
- Department of Immunology, School of Medicine, Iran University of Medical Sciences, Tehran, 5618985991, Iran
| | - Vahid Asghariazar
- Deputy of Research & Technology, Ardabil University of Medical Sciences, Ardabil, 5618985991, Iran
| | - Mahdi Taghadosi
- Department of Immunology, Kermanshah University of Medical Sciences, Kermanshah, 6714869914, Iran
| | - Elham Safarzadeh
- Department of Microbiology, Parasitology, & Immunology, Ardabil University of Medical Sciences, Ardabil, 5618985991, Iran
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Ferlini L, Nonclercq A, Su F, Creteur J, Taccone FS, Gaspard N. Sepsis modulates cortical excitability and alters the local and systemic hemodynamic response to seizures. Sci Rep 2022; 12:11336. [PMID: 35790848 PMCID: PMC9256588 DOI: 10.1038/s41598-022-15426-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 06/23/2022] [Indexed: 11/09/2022] Open
Abstract
Non-convulsive seizures and status epilepticus are frequent and associated with increased mortality in septic patients. However, the mechanism through which seizures impact outcome in these patients is unclear. As previous studies yielded an alteration of neurovascular coupling (NVC) during sepsis, we hypothesized that non-convulsive seizures, might further impair NVC, leading to brain tissue hypoxia. We used a previously developed ovine model of sepsis. Animals were allocated to sham procedure or sepsis; septic animals were studied either during the hyperdynamic phase (sepsis group) or after septic shock occurrence (septic shock group). After allocation, seizures were induced by cortical application of penicillin. We recorded a greater seizure-induced increase in the EEG gamma power in the sepsis group than in sham. Using a neural mass model, we also found that the theoretical activity of the modeled inhibitory interneurons, thought to be important to reproduce gamma oscillations, were relatively greater in the sepsis group. However, the NVC was impaired in sepsis animals, despite a normal brain tissue oxygenation. In septic shock animals, it was not possible to induce seizures. Cortical activity declined in case of septic shock, but it did not differ between sham or sepsis animals. As the alteration in NVC preceded cortical activity reduction, we suggest that, during sepsis progression, the NVC inefficiency could be partially responsible for the alteration of brain function, which might prevent seizure occurrence during septic shock. Moreover, we showed that cardiac output decreased during seizures in sepsis animals instead of increasing as in shams. The alteration of the seizure-induced systemic hemodynamic variations in sepsis might further affect cerebrovascular response to neuronal activation. Our findings support the hypothesis that anomalies in the cerebral blood flow regulation may contribute to the sepsis-associated encephalopathy and that seizures might be dangerous in such a vulnerable setting.
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Affiliation(s)
- Lorenzo Ferlini
- Department of Neurology, Erasme Hospital, Université Libre de Bruxelles, Route de Lennik, 808, 1070, Brussels, Belgium
| | - Antoine Nonclercq
- Bio-, Electro- And Mechanical Systems (BEAMS), Université Libre de Bruxelles, Avenue F.D. Roosevelt 50 CP165/56, 1050, Brussels, Belgium
| | - Fuhong Su
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Route de Lennik, 808, 1070, Brussels, Belgium
| | - Jacques Creteur
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Route de Lennik, 808, 1070, Brussels, Belgium
| | - Fabio Silvio Taccone
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Route de Lennik, 808, 1070, Brussels, Belgium
| | - Nicolas Gaspard
- Department of Neurology, Erasme Hospital, Université Libre de Bruxelles, Route de Lennik, 808, 1070, Brussels, Belgium.
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6
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de Witte LD, Wang Z, Snijders GLJL, Mendelev N, Liu Q, Sneeboer MAM, Boks MPM, Ge Y, Haghighi F. Contribution of Age, Brain Region, Mood Disorder Pathology, and Interindividual Factors on the Methylome of Human Microglia. Biol Psychiatry 2022; 91:572-581. [PMID: 35027166 PMCID: PMC11181298 DOI: 10.1016/j.biopsych.2021.10.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 10/20/2021] [Accepted: 10/21/2021] [Indexed: 12/19/2022]
Abstract
BACKGROUND Transcriptome studies have revealed age-, disease-, and region-associated microglial phenotypes reflecting changes in microglial function during development, aging, central nervous system homeostasis, and pathology. The molecular mechanisms that contribute to these transcriptomic changes are largely unknown. The aim of this study was to characterize the DNA methylation landscape of human microglia and the factors that contribute to variations in the microglia methylome. We hypothesized that both age and brain region would have a large impact on DNA methylation in microglia. METHODS Microglia from postmortem brain tissue of four different brain regions of 22 donors, encompassing 1 patient with schizophrenia, 13 patients with mood disorder pathology, and 8 control subjects, were isolated and assayed using a genome-wide methylation array. RESULTS We found that human microglial cells have a methylation profile distinct from bulk brain tissue and neurons, and age explained a considerable part of the variation. Additionally, we showed that interindividual factors had a much larger effect on the methylation landscape of microglia than brain region, which was also seen at the transcriptome level. In our exploratory analysis, we found various differentially methylated regions that were related to disease status (mood disorder vs. control). This included differentially methylated regions that are linked to gene expression in microglia, as well as to myeloid cell function or neuropsychiatric disorders. CONCLUSIONS Although based on relatively small samples, these findings suggest that the methylation profile of microglia is responsive to interindividual variations and thereby plays an important role in the heterogeneity of microglia observed at the transcriptome level.
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Affiliation(s)
- Lot D de Witte
- Mental Illness Research, Education and Clinical Center, James J Peters VA Medical Center, Bronx, New York; Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Zhaoyu Wang
- Mental Illness Research, Education and Clinical Center, James J Peters VA Medical Center, Bronx, New York; Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Gijsje L J L Snijders
- Mental Illness Research, Education and Clinical Center, James J Peters VA Medical Center, Bronx, New York; Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Natalia Mendelev
- Mental Illness Research, Education and Clinical Center, James J Peters VA Medical Center, Bronx, New York; Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Qingkun Liu
- Mental Illness Research, Education and Clinical Center, James J Peters VA Medical Center, Bronx, New York; Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Marjolein A M Sneeboer
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York; Department of Psychiatry, University Medical Center Utrecht, UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands; Department of Translational Neuroscience, University Medical Center Utrecht, UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
| | - Marco P M Boks
- Department of Psychiatry, University Medical Center Utrecht, UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
| | - Yongchao Ge
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Fatemeh Haghighi
- Mental Illness Research, Education and Clinical Center, James J Peters VA Medical Center, Bronx, New York; Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York; Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York.
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7
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Nortey J, Smith D, Seitzman GD, Gonzales JA. Topical Therapeutic Options in Corneal Neuropathic Pain. Front Pharmacol 2022; 12:769909. [PMID: 35173607 PMCID: PMC8841414 DOI: 10.3389/fphar.2021.769909] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 12/28/2021] [Indexed: 11/16/2022] Open
Abstract
Purpose of Review: Corneal neuropathic pain can be difficult to treat, particularly due to its lack of response to standard dry eye therapies. We describe a variety of topical therapeutic options that are available to treat corneal neuropathic pain with a significant or primary peripheral component. We also describe possible mechanisms of action for such topical therapies. Recent Findings: Topical corticosteroids and blood-derived tear preparations can be helpful. Newer therapies, including topical lacosamide and low-dose naltrexone are emerging therapeutic options that may also be considered. Summary: Corneal neuropathic pain with a significant peripheral component may be managed with a variety of topical therapeutic options.
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Affiliation(s)
- Jeremy Nortey
- School of Medicine, University of North Carolina, Chapel Hill, NC, United Statesa
- Francis I. Proctor Foundation, University of California, San Francisco, San Francisco, CA, United States
| | - David Smith
- A&O Compounding Pharmacy, Vallejo, CA, United States
| | - Gerami D. Seitzman
- Francis I. Proctor Foundation, University of California, San Francisco, San Francisco, CA, United States
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, United States
| | - John A. Gonzales
- Francis I. Proctor Foundation, University of California, San Francisco, San Francisco, CA, United States
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, United States
- *Correspondence: John A. Gonzales,
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8
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Davoli-Ferreira M, Thomson CA, McCoy KD. Microbiota and Microglia Interactions in ASD. Front Immunol 2021; 12:676255. [PMID: 34113350 PMCID: PMC8185464 DOI: 10.3389/fimmu.2021.676255] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 05/12/2021] [Indexed: 12/12/2022] Open
Abstract
Autism spectrum disorders (ASD) are serious, highly variable neurodevelopmental disorders, commonly characterized by the manifestation of specific behavioral abnormalities, such as stereotypic behaviors and deficits in social skills, including communication. Although the neurobiological basis for ASD has attracted attention in recent decades, the role of microglial cells, which are the main resident myeloid cell population in the brain, is still controversial and underexplored. Microglia play several fundamental roles in orchestrating brain development and homeostasis. As such, alterations in the intrinsic functions of these cells could be one of the driving forces responsible for the development of various neurodevelopmental disorders, including ASD. Microglia are highly sensitive to environmental cues. Amongst the environmental factors known to influence their intrinsic functions, the gut microbiota has emerged as a central player, controlling both microglial maturation and activation. Strikingly, there is now compelling data suggesting that the intestinal microbiota can play a causative role in driving the behavioural changes associated with ASD. Not only is intestinal dysbiosis commonly reported in ASD patients, but therapies targeting the microbiome can markedly alleviate behavioral symptoms. Here we explore the emerging mechanisms by which altered microglial functions could contribute to several major etiological factors of ASD. We then demonstrate how pre- and postnatal environmental stimuli can modulate microglial cell phenotype and function, underpinning the notion that reciprocal interactions between microglia and intestinal microbes could play a crucial role in ASD aetiology.
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Affiliation(s)
- Marcela Davoli-Ferreira
- Department of Physiology and Pharmacology, Snyder Institute of Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Carolyn A Thomson
- Department of Physiology and Pharmacology, Snyder Institute of Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Kathy D McCoy
- Department of Physiology and Pharmacology, Snyder Institute of Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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9
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Sarno E, Moeser AJ, Robison AJ. Neuroimmunology of depression. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2021; 91:259-292. [PMID: 34099111 DOI: 10.1016/bs.apha.2021.03.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Depression is one of the leading causes of disability worldwide and a major contributor to the global burden of disease, yet the cellular and molecular etiology of depression remain largely unknown. Major Depressive Disorder (MDD) is associated with a variety of chronic physical inflammatory and autoimmune disorders, and mood disorders may act synergistically with other medical disorders to worsen patient outcomes. Here, we outline the neuroimmune complement, explore the evidence for altered immune system function in MDD, and present some of the potential mechanisms by which immune cells and molecules may drive the onset and course of MDD. These include pro-inflammatory signaling, alterations in the hypothalamic-pituitary-adrenal axis, dysregulation of the serotonergic and noradrenergic neurotransmitter systems, neuroinflammation, and meningeal immune dysfunction. Finally, we discuss the interactions between current antidepressants and the immune system and propose the possibility of immunomodulatory drugs as potential novel antidepressant treatments.
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Affiliation(s)
- Erika Sarno
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Adam J Moeser
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - Alfred J Robison
- Department of Physiology, Michigan State University, East Lansing, MI, United States.
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10
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Role of Microglia in Modulating Adult Neurogenesis in Health and Neurodegeneration. Int J Mol Sci 2020; 21:ijms21186875. [PMID: 32961703 PMCID: PMC7555074 DOI: 10.3390/ijms21186875] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 09/18/2020] [Indexed: 02/06/2023] Open
Abstract
Microglia are the resident immune cells of the brain, constituting the powerhouse of brain innate immunity. They originate from hematopoietic precursors that infiltrate the developing brain during different stages of embryogenesis, acquiring a phenotype characterized by the presence of dense ramifications. Microglial cells play key roles in maintaining brain homeostasis and regulating brain immune responses. They continuously scan and sense the brain environment to detect any occurring changes. Upon detection of a signal related to physiological or pathological processes, the cells are activated and transform to an amoeboid-like phenotype, mounting adequate responses that range from phagocytosis to secretion of inflammatory and trophic factors. The overwhelming evidence suggests that microglia are crucially implicated in influencing neuronal proliferation and differentiation, as well as synaptic connections, and thereby cognitive and behavioral functions. Here, we review the role of microglia in adult neurogenesis under physiological conditions, and how this role is affected in neurodegenerative diseases.
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11
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Litvin DG, Denstaedt SJ, Borkowski LF, Nichols NL, Dick TE, Smith CB, Jacono FJ. Peripheral-to-central immune communication at the area postrema glial-barrier following bleomycin-induced sterile lung injury in adult rats. Brain Behav Immun 2020; 87:610-633. [PMID: 32097765 PMCID: PMC8895345 DOI: 10.1016/j.bbi.2020.02.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 02/02/2020] [Accepted: 02/13/2020] [Indexed: 02/07/2023] Open
Abstract
The pathways for peripheral-to-central immune communication (P → C I-comm) following sterile lung injury (SLI) are unknown. SLI evokes systemic and central inflammation, which alters central respiratory control and viscerosensory transmission in the nucleus tractus solitarii (nTS). These functional changes coincide with increased interleukin-1 beta (IL-1β) in the area postrema, a sensory circumventricular organ that connects P → C I-comm to brainstem circuits that control homeostasis. We hypothesize that IL-1β and its downstream transcriptional target, cyclooxygenase-2 (COX-2), mediate P → C I-comm in the nTS. In a rodent model of SLI induced by intratracheal bleomycin (Bleo), the sigh frequency and duration of post-sigh apnea increased in Bleo- compared to saline- treated rats one week after injury. This SLI-dependent change in respiratory control occurred concurrently with augmented IL-1β and COX-2 immunoreactivity (IR) in the funiculus separans (FS), a barrier between the AP and the brainstem. At this barrier, increases in IL-1β and COX-2 IR were confined to processes that stained for glial fibrillary acidic protein (GFAP) and that projected basolaterally to the nTS. Further, FS radial-glia did not express TNF-α or IL-6 following SLI. To test our hypothesis, we blocked central COX-1/2 activity by intracerebroventricular (ICV) infusion of Indomethacin (Ind). Continuous ICV Ind treatment prevented Bleo-dependent increases in GFAP + and IL-1β + IR, and restored characteristics of sighs that reset the rhythm. These data indicate that changes in sighs following SLI depend partially on activation of a central COX-dependent P → C I-comm via radial-glia of the FS.
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Affiliation(s)
- David G Litvin
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Department of Fundamental Neuroscience, University of Lausanne, 1005 Lausanne, Switzerland
| | - Scott J Denstaedt
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109, United States
| | - Lauren F Borkowski
- Department of Biomedical Sciences, University of Missouri College of Veterinary Medicine, Columbia, MO 65212, United States
| | - Nicole L Nichols
- Department of Biomedical Sciences, University of Missouri College of Veterinary Medicine, Columbia, MO 65212, United States
| | - Thomas E Dick
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Corey B Smith
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Frank J Jacono
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, OH 44106, United States.
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12
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Systemic TNF-α blockade attenuates anxiety and depressive-like behaviors in db/db mice through downregulation of inflammatory signaling in peripheral immune cells. Saudi Pharm J 2020; 28:621-629. [PMID: 32435144 PMCID: PMC7229333 DOI: 10.1016/j.jsps.2020.04.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 04/02/2020] [Indexed: 12/14/2022] Open
Abstract
Research studies have indicated that the comorbidity burden of mood disorders and obesity is reasonably high. Insulin signaling has been shown to modulate multiple physiological functions in the brain, indicating its association with neuropsychiatric diseases, including mood disorders. Leptin is a hormone responsible for regulating body weight and insulin homeostasis. Previous studies on db/db mice (a mouse model that carries a spontaneous genetic mutation in leptin receptor Leprdb) have shown that they exhibit inflammation as well as neurobehavioral traits associated with mood. Therefore, targeting inflammatory pathways such as TNF-α may be an effective strategy in the treatment of obesity-linked mood disorders. The objective of this study was to investigate the effect of long-term administration of etanercept (a TNF-α blocker) on anxiety and depressive-like behaviors in db/db mice. This was performed using light/dark box, forced swim, and open field tests with lean littermate wild type (WT) mice serving as a control group. Using flow cytometry in peripheral blood, we further examined the molecular effects of etanercept on NF-κB p65, TNF-α, IL-17A, and TLR-4 expressing CD4+, CD8+, and CD14+ cells in the peripheral blood. Our data show that peripheral administration of etanercept decreased these cells in db/db mice. Furthermore, our results indicated that peripheral administration of etanercept reduced anxiety and depressive-like behaviors. Therefore, targeting TNF-α signaling might be an effective strategy for modulating obesity-associated depression and anxiety.
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13
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Yurinskaya MM, Garbuz DG, Evgen’ev MB, Vinokurov MG. Exogenous HSP70 and Signaling Pathways Involved in the Inhibition of LPS-Induced Neurotoxicity of Neuroblastoma Cells. Mol Biol 2020. [DOI: 10.1134/s0026893320010161] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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14
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Vargas-Caraveo A, Sayd A, Robledo-Montaña J, Caso JR, Madrigal JLM, García-Bueno B, Leza JC. Toll-like receptor 4 agonist and antagonist lipopolysaccharides modify innate immune response in rat brain circumventricular organs. J Neuroinflammation 2020; 17:6. [PMID: 31906991 PMCID: PMC6945636 DOI: 10.1186/s12974-019-1690-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 12/23/2019] [Indexed: 01/02/2023] Open
Abstract
Background The circumventricular organs (CVOs) are blood-brain-barrier missing structures whose activation through lipopolysaccharide (LPS) is a starting point for TLR-driven (Toll-like receptors) neuroinflammation. The aim of this study was to evaluate in the CVO area postrema (AP), subfornical organ (SFO), and median eminence (ME), the inflammatory response to two TLR4 agonists: LPS from Escherichia coli (EC-LPS), the strongest endotoxin molecule described, and LPS from Porphyromonas gingivalis (PG-LPS), a pathogenic bacteria present in the periodontium related to neuroinflammation in neurodegenerative/psychiatric diseases. The response to LPS from the cyanobacteria Rhodobacter sphaeroides (RS-LPS), a TLR4 antagonist with an interesting anti-inflammatory potential, was also assessed. Methods LPSs were intraperitoneally administered to Wistar rats and, as indicatives of neuroinflammation in CVOs, the cellular localization of the nuclear factor NF-κB was studied by immunofluorescence, and microglia morphology was quantified by fractal and skeleton analysis. Results Data showed that EC-LPS increased NF-κB nuclear translocation in the three CVOs studied and PG-LPS only induced NF-κB nuclear translocation in the ME. RS-LPS showed no difference in NF-κB nuclear translocation compared to control. Microglia in the three CVOs showed an ameboid-shape after EC-LPS exposure, whereas PG-LPS only elicited a mild tendency to induce an ameboid shape. On the other hand, RS-LPS produced a markedly elongated morphology described as “rod” microglia in the three CVOs. Conclusions In conclusion, at the doses tested, EC-LPS induces a stronger neuroinflammatory response than PG-LPS in CVOs, which might be related to their different potency as TLR4 agonists. The non-reduction of basal NF-κB activation and induction of rod microglia by RS-LPS, a cell morphology only present in severe brain injury and infections, suggests that this molecule must be carefully studied before being proposed as an anti-inflammatory treatment for neuroinflammation related to neurodegenerative/psychiatric diseases.
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Affiliation(s)
- Alejandra Vargas-Caraveo
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain. .,Biological and Health Sciences Division, Metropolitan Autonomous University (UAM), Campus Lerma, 52005, Lerma, Mexico.
| | - Aline Sayd
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
| | - Javier Robledo-Montaña
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
| | - Javier R Caso
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
| | - José L M Madrigal
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
| | - Borja García-Bueno
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain.
| | - Juan C Leza
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
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Zhang S, Xue R, Hu R. The neuroprotective effect and action mechanism of polyphenols in diabetes mellitus-related cognitive dysfunction. Eur J Nutr 2019; 59:1295-1311. [PMID: 31598747 DOI: 10.1007/s00394-019-02078-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 08/10/2019] [Indexed: 12/21/2022]
Abstract
BACKGROUND Diabetes mellitus (DM) is a complex and prevalent metabolic disorder worldwide. Strong evidence has emerged that DM is a risk factor for the accelerated rate of cognitive decline and the development of dementia. Though traditional pharmaceutical agents are efficient for the management of DM and DM-related cognitive decrement, long-term use of these drugs are along with undesired side effects. Therefore, tremendous studies have focused on the therapeutic benefits of natural compounds at present. Ample evidence exists to prove that polyphenols are capable to modulate diabetic neuropathy with minimal toxicity and adverse effects. PURPOSE To describe the benefits and mechanisms of polyphenols on DM-induced cognitive dysfunction. In this review, we introduce an updated overview of associations between DM and cognitive dysfunction. The risk factors as well as pathological and molecular mechanisms of DM-induced cognitive dysfunction are summarized. More importantly, many active polyphenols that possess preventive and therapeutic effects on DM-induced cognitive dysfunction and the potential signaling pathways involved in the action are highlighted. CONCLUSIONS The therapeutic effects of polyphenols on DM-related cognitive dysfunction pave a novel way for the management of diabetic encephalopathy.
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Affiliation(s)
- Shenshen Zhang
- College of Public Health, Zhengzhou University, Zhengzhou, China.
| | - Ran Xue
- College of Public Health, Zhengzhou University, Zhengzhou, China
| | - Ruizhe Hu
- School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou, China.
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16
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Laffer B, Bauer D, Wasmuth S, Busch M, Jalilvand TV, Thanos S, Meyer Zu Hörste G, Loser K, Langmann T, Heiligenhaus A, Kasper M. Loss of IL-10 Promotes Differentiation of Microglia to a M1 Phenotype. Front Cell Neurosci 2019; 13:430. [PMID: 31649508 PMCID: PMC6794388 DOI: 10.3389/fncel.2019.00430] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 09/09/2019] [Indexed: 12/12/2022] Open
Abstract
Microglia represent the primary resident immune cells of the central nervous system (CNS) and modulate local immune responses. Depending on their physiological functions, microglia can be classified into pro- (M1) and anti-inflammatory (M2) phenotype. Interleukin (IL)-10 is an important modulator of neuronal homeostasis, with anti-inflammatory and neuroprotective functions, and can be released by microglia. Here, we investigated how IL-10 deficiency affected the M1/2 polarization of primary microglia upon lipopolysaccharide (LPS) stimulation in vitro. Microglia phenotypes were analyzed via flow cytometry. Cytokine and chemokine secretion were examined by ELISA and bead-based multiplex LEGENDplexTM. Our results showed that genetic depletion of IL-10 led to elevated M1 like phenotype (CD86+ CD206−) under pro-inflammatory conditions associated with increased frequency of IL-6+, TNF-α+ cells and enhanced release of several pro-inflammatory chemokines. Absence of IL-10 led to an attenuated M2 like phenotype (CD86− CD206+) and a reduced secretion of TGF-β1 upon LPS stimulation. In conclusion, IL-10 deficiency may promote the polarization of microglia into M1-prone phenotype under pro-inflammatory conditions.
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Affiliation(s)
- Björn Laffer
- Department of Ophthalmology and Ophtha-Lab at St. Franziskus-Hospital, Münster, Germany.,Department of Ophthalmology, University of Duisburg-Essen, Essen, Germany
| | - Dirk Bauer
- Department of Ophthalmology and Ophtha-Lab at St. Franziskus-Hospital, Münster, Germany
| | - Susanne Wasmuth
- Department of Ophthalmology and Ophtha-Lab at St. Franziskus-Hospital, Münster, Germany
| | - Martin Busch
- Department of Ophthalmology and Ophtha-Lab at St. Franziskus-Hospital, Münster, Germany
| | - Tida Viola Jalilvand
- Department of Ophthalmology and Ophtha-Lab at St. Franziskus-Hospital, Münster, Germany.,Department of Experimental Ophthalmology, Westphalian Wilhelms University of Münster, Münster, Germany
| | - Solon Thanos
- Department of Experimental Ophthalmology, Westphalian Wilhelms University of Münster, Münster, Germany
| | - Gerd Meyer Zu Hörste
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany
| | - Karin Loser
- Department of Dermatology - Experimental Dermatology and Immunobiology of the Skin, University of Münster, Münster, Germany
| | - Thomas Langmann
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Arnd Heiligenhaus
- Department of Ophthalmology and Ophtha-Lab at St. Franziskus-Hospital, Münster, Germany.,University of Duisburg-Essen, Essen, Germany
| | - Maren Kasper
- Department of Ophthalmology and Ophtha-Lab at St. Franziskus-Hospital, Münster, Germany
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17
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Shin SH, Kim EK, Lee KY, Kim HS. TNF-α antagonist attenuates systemic lipopolysaccharide-induced brain white matter injury in neonatal rats. BMC Neurosci 2019; 20:45. [PMID: 31470812 PMCID: PMC6716877 DOI: 10.1186/s12868-019-0529-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 08/26/2019] [Indexed: 12/04/2022] Open
Abstract
Background Systemic inflammation is an important risk factor for neurodevelopmental impairments in preterm infants. Premyelinating oligodendrocytes are main building blocks of white matter in preterm infants and vulnerable to oxidative stress and excitotoxic stress. Tumour necrosis factor-α (TNF-α) plays important roles in systemic inflammation and local inflammation leading to apoptosis of premyelinating oligodendrocytes and white matter injury (WMI) in brain tissue. This study was conducted to investigate whether etanercept, a TNF-α antagonist, could attenuate systemic lipopolysaccharide (LPS)-induced WMI in the immature brain. Results We found that intraperitoneal LPS administration caused systemic and local inflammation in brain tissue. Subsequent etanercept treatment significantly attenuated LPS-induced inflammation in brain tissue as well as in systemic circulation. Intraperitoneal LPS also induced microgliosis and astrocytosis in the cingulum and etanercept treatment reduced LPS-induced microgliosis and astrocytosis. Additionally, systemic LPS-induced apoptosis of oligodendrocyte precursor cells was observed, which was lessened by etanercept treatment. The concentration of etanercept in the CSF was higher when it was administrated with LPS than when administrated with a vehicle. Conclusions It appears that etanercept reduce WMI in the neonatal rat brain via attenuation of systemic and local inflammation. This study provides preclinical data suggesting etanercept-mediated modulation of inflammation as a promising approach to reduce WMI caused by sepsis or necrotizing enterocolitis in preterm infants.
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Affiliation(s)
- Seung Han Shin
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, South Korea
| | - Ee-Kyung Kim
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, South Korea.
| | - Kyung-Yup Lee
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, South Korea
| | - Han-Suk Kim
- Department of Pediatrics, Seoul National University College of Medicine, Seoul National University Children's Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, South Korea
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18
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Knockdown of the CXCL12/CXCR7 chemokine pathway results in learning deficits and neural progenitor maturation impairment in mice. Brain Behav Immun 2019; 80:697-710. [PMID: 31100368 DOI: 10.1016/j.bbi.2019.05.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 05/10/2019] [Accepted: 05/13/2019] [Indexed: 12/26/2022] Open
Abstract
In adult brain, the chemokine CXCL12 and its receptors CXCR4 and CXCR7 are expressed in neural progenitor and glial cells. Conditional Cxcl12 or Cxcr4 gene knockout in mice leads to severe alterations in neural progenitor proliferation, migration and differentiation. As adult hippocampal neurogenesis is involved in learning and memory processes, we investigated the long-term effects of reduced expression of CXCL12 or CXCR7 in heterozygous Cxcl12+/- and Cxcr7+/- animals (KD mice) on hippocampal neurogenesis, neuronal differentiation and memory processing. In Cxcl12 KD mice, Cxcr4 mRNA expression was reduced, whereas Cxcr7 was slightly increased. Conversely, in Cxcr7 KD mice, both Cxcr4 and Cxcl12 mRNA levels were decreased. Moreover, Cxcl12 KD animals showed marked behavioral and learning deficits that were associated with impaired neurogenesis in the hippocampus. Conversely, Cxcr7 KD animals showed mild learning deficits with normal neurogenesis, but reduced cell differentiation, measured with doublecortin immunolabeling. These findings suggested that a single Cxcl12 or Cxcr7 allele might not be sufficient to maintain the hippocampal niche functionality throughout life, and that heterozygosity might represent a susceptibility factor for memory dysfunction progression.
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Aguilera G, Colín-González AL, Rangel-López E, Chavarría A, Santamaría A. Redox Signaling, Neuroinflammation, and Neurodegeneration. Antioxid Redox Signal 2018; 28:1626-1651. [PMID: 28467722 DOI: 10.1089/ars.2017.7099] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Production of pro-inflammatory and anti-inflammatory cytokines is part of the defense system that mostly microglia and macrophages display to induce normal signaling to counteract the deleterious actions of invading pathogens in the brain. Also, redox activity in the central nervous system (CNS) constitutes an integral part of the metabolic processes needed by cells to exert their normal molecular and biochemical functions. Under normal conditions, the formation of reactive oxygen and nitrogen species, and the following oxidative activity encounter a healthy balance with immunological responses to preserve cell functions in the brain. However, under different pathological conditions, inflammatory responses recruit pro-oxidant signals and vice versa. The aim of this article is to review the basic concepts about the triggering of inflammatory and oxidative responses in the CNS. Recent Advances: Diverse concurrent toxic pathways are described to provide a solid mechanistic scope for considering intervention at the experimental and clinical levels that are aimed at diminishing the harmful actions of these two contributing factors to nerve cell damage. Critical Issues and Future Directions: The main conclusion supports the existence of a narrow cross-talk between pro-inflammatory and oxidative signals that can lead to neuronal damage and subsequent neurodegeneration. Further investigation about critical pathways crosslinking oxidative stress and inflammation will strength our knowlegde on this topic. Antioxid. Redox Signal. 28, 1626-1651.
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Affiliation(s)
- Gabriela Aguilera
- 1 Laboratorio de Aminoácidos Excitadores, Instituto Nacional de Neurología y Neurocirugía , Mexico City, Mexico
| | - Ana Laura Colín-González
- 1 Laboratorio de Aminoácidos Excitadores, Instituto Nacional de Neurología y Neurocirugía , Mexico City, Mexico
| | - Edgar Rangel-López
- 1 Laboratorio de Aminoácidos Excitadores, Instituto Nacional de Neurología y Neurocirugía , Mexico City, Mexico
| | - Anahí Chavarría
- 2 Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México , Mexico City, Mexico
| | - Abel Santamaría
- 1 Laboratorio de Aminoácidos Excitadores, Instituto Nacional de Neurología y Neurocirugía , Mexico City, Mexico
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20
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O'Callaghan P, Zhang X, Li JP. Heparan Sulfate Proteoglycans as Relays of Neuroinflammation. J Histochem Cytochem 2018; 66:305-319. [PMID: 29290138 DOI: 10.1369/0022155417742147] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Heparan sulfate proteoglycans (HSPGs) are implicated as inflammatory mediators in a variety of settings, including chemokine activation, which is required to recruit circulating leukocytes to infection sites. Heparan sulfate (HS) polysaccharide chains are highly interactive and serve co-receptor roles in multiple ligand:receptor interactions. HS may also serve as a storage depot, sequestering ligands such as cytokines and restricting their access to binding partners. Heparanase, through its ability to fragment HS chains, is a key regulator of HS function and has featured prominently in studies of HS's involvement in inflammatory processes. This review focuses on recent discoveries regarding the role of HSPGs, HS, and heparanase during inflammation, with particular focus on the brain. HS chains emerge as critical go-betweens in multiple aspects of the inflammatory response-relaying signals between receptors and cells. The molecular interactions proposed to occur between HSPGs and the pathogen receptor toll-like receptor 4 (TLR4) are discussed, and we summarize some of the contrasting roles that HS and heparanase have been assigned in diseases associated with chronic inflammatory states, including Alzheimer's disease (AD). We conclude by briefly discussing how current knowledge could potentially be applied to augment HS-mediated events during sustained neuroinflammation, which contributes to neurodegeneration in AD.
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Affiliation(s)
- Paul O'Callaghan
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Xiao Zhang
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Jin-Ping Li
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
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21
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Mao L, Gao W, Chen S, Song Y, Song C, Zhou Z, Zhao H, Zhou K, Wang W, Zhu K, Liu C, Mei X. Epothilone B impairs functional recovery after spinal cord injury by increasing secretion of macrophage colony-stimulating factor. Cell Death Dis 2017; 8:e3162. [PMID: 29095439 PMCID: PMC5775408 DOI: 10.1038/cddis.2017.542] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Revised: 08/30/2017] [Accepted: 09/12/2017] [Indexed: 12/13/2022]
Abstract
The microtubule-stabilizing drug epothilone B (epoB) has shown potential value in the treatment of spinal cord injury (SCI) through diverse mechanisms. However, it remains elusive why a limited overall effect was observed. We aim to investigate the limiting factors underlying functional recovery promoted by epoB. The same SCI model treated by epoB was established as discussed previously. We used a cerebrospinal fluid (CSF) sample to assess the changes in cytokines in milieu of the SCI lesion site after epoB treatment. We then analyzed the source of cytokines, the state of microglia/macrophages/monocytes (M/Ms), and the recruitment of neutrophil in the lesion site by using the results of antibody array. Following these findings, we further evaluated the motor functional recovery caused by the reshaped microenvironment. Systemic administration of epoB significantly increased levels of several cytokines in the CSF of the rat SCI model; macrophage colony-stimulating factor (M-CSF) secreted by intact central nervous system (CNS) cells was one of the cytokines with increased levels. Along with epoB and other cytokines, M-CSF reshapes the SCI milieu by activating the microglias, killing bone marrow-derived macrophages, polarizing the M/M to M1 phenotype, and activating downstream cytokines to exacerbate the SCI injury, but it also increases the expression of neurotrophic factors. Anti-inflammatory therapy using a neutralizing antibody mix shows encouraging results. Using in vivo experiments, our findings indicate that epoB inhibits the SCI functional recovery in many ways by reshaping the milieu, which counteracts the therapeutic efficacy that led to the limited overall effectiveness.
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Affiliation(s)
- Liang Mao
- Department of Oncology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China.,Key Laboratory of Medical Tissue Engineering of Liaoning Province, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Wei Gao
- Department of Basic Medical Sciences, Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Shurui Chen
- Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Ying Song
- Key Laboratory of Medical Tissue Engineering of Liaoning Province, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Changwei Song
- Key Laboratory of Medical Tissue Engineering of Liaoning Province, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China.,Department of Hand Surgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Zipeng Zhou
- Department of Orthopedic Surgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Haosen Zhao
- Department of Orthopedic Surgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Kang Zhou
- Department of Orthopedic Surgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Wei Wang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Kunming Zhu
- Department of Orthopedic Surgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Chang Liu
- Department of Endocrinology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
| | - Xifan Mei
- Key Laboratory of Medical Tissue Engineering of Liaoning Province, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China.,Department of Orthopedic Surgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121000, People's Republic of China
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22
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da Fonseca ACC, Amaral R, Garcia C, Geraldo LH, Matias D, Lima FRS. Microglia in Cancer: For Good or for Bad? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 949:245-261. [PMID: 27714693 DOI: 10.1007/978-3-319-40764-7_12] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Glioblastoma is a malignant tumor of astrocytic origin that is highly invasive, proliferative and angiogenic. Despite current advances in multimodal therapies, such as surgery, radio- and chemotherapy, the outcome for patients with glioblastoma is nearly always fatal. The glioblastoma microenvironment has a tremendous influence over the tumor growth and spread. Microglia and macrophages are abundant cells in the tumor mass. Increasing evidence indicates that glioblastoma recruits these cell populations and signals in a way that microglia and macrophages are subverted to promote tumor progression. In this chapter, we discuss some aspects of the interaction between microglia and glioblastoma, consequences of this interaction for tumor progression and the possibility of microglial cells being used as therapeutic vectors, which opens up new alternatives for the development of GBM therapies targeting microglia.
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Affiliation(s)
- Anna Carolina Carvalho da Fonseca
- Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, Rio de Janeiro, RJ, 21949-590, Brazil
| | - Rackele Amaral
- Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, Rio de Janeiro, RJ, 21949-590, Brazil
| | - Celina Garcia
- Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, Rio de Janeiro, RJ, 21949-590, Brazil
| | - Luiz Henrique Geraldo
- Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, Rio de Janeiro, RJ, 21949-590, Brazil
| | - Diana Matias
- Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, Rio de Janeiro, RJ, 21949-590, Brazil
| | - Flavia Regina Souza Lima
- Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, Rio de Janeiro, RJ, 21949-590, Brazil.
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23
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Jensen P, Myhre CL, Lassen PS, Metaxas A, Khan AM, Lambertsen KL, Babcock AA, Finsen B, Larsen MR, Kempf SJ. TNFα affects CREB-mediated neuroprotective signaling pathways of synaptic plasticity in neurons as revealed by proteomics and phospho-proteomics. Oncotarget 2017; 8:60223-60242. [PMID: 28947966 PMCID: PMC5601134 DOI: 10.18632/oncotarget.19428] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 07/11/2017] [Indexed: 11/25/2022] Open
Abstract
Neuroinflammation is a hallmark of Alzheimer's disease and TNFα as the main inducer of neuroinflammation has neurodegenerative but also pro-regenerative properties, however, the dose-dependent molecular changes on signaling pathway level are not fully understood. We performed quantitative proteomics and phospho-proteomics to target this point. In HT22 cells, we found that TNFα reduced mitochondrial signaling and inhibited mTOR protein translation signaling but also led to induction of neuroprotective MAPK-CREB signaling. Stimulation of human neurons with TNFα revealed similar cellular mechanisms. Moreover, a number of synaptic plasticity-associated genes were altered in their expression profile including CREB. SiRNA-mediated knockdown of CREB in human neurons prior to TNFα stimulation led to a reduced number of protein/phospho-protein hits compared to siRNA-mediated knockdown of CREB or TNFα stimulation alone and countermeasured the reduced CREB signaling. In vivo data of TNFα knockout mice showed that learning ability did not depend on TNFα per se but that TNFα was essential for preserving the learning ability after episodes of lipopolysaccharide-induced neuroinflammation. This may be based on modulation of CREB/CREB signaling as revealed by the in vitro / in vivo data. Our data show that several molecular targets and signaling pathways induced by TNFα in neurons resemble those seen in Alzheimer's disease pathology.
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Affiliation(s)
- Pia Jensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Christa L Myhre
- Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Pernille S Lassen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Athanasios Metaxas
- Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Asif M Khan
- Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Current address: Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Kate L Lambertsen
- Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Neurology, Odense University Hospital, Odense, Denmark.,BRIDGE, Brain Research-Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Alicia A Babcock
- Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Bente Finsen
- Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,BRIDGE, Brain Research-Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Martin R Larsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Stefan J Kempf
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
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Wang H, Xu YS, Wang ML, Cheng C, Bian R, Yuan H, Wang Y, Guo T, Zhu LL, Zhou H. Protective effect of naringin against the LPS-induced apoptosis of PC12 cells: Implications for the treatment of neurodegenerative disorders. Int J Mol Med 2017; 39:819-830. [PMID: 28260042 PMCID: PMC5360435 DOI: 10.3892/ijmm.2017.2904] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 02/10/2017] [Indexed: 01/01/2023] Open
Abstract
Several studies have demonstrated that increased apoptosis plays an essential role in neurodegenerative disorders. It has been demonstrated that lipopolysaccharide (LPS) induces apoptosis largely through the production of intracellular reactive oxygen species (ROS) and inflammatory mediators. In this study, we investigated the potential protective mechanisms of naringin (Nar), a pummelo peel extract, on LPS-induced PC12 cell apoptosis. Nar pre-conditioning prior to stimulation with LPS for 18 h was a prerequisite for evaluating PC12 cell viability and the protective mechanisms of Nar. Nar significantly improved cell survival in a time- and concentration-dependent manner. On the one hand, Nar downregulated cytochrome P450 2E1 (CYP2E1), inhibited the release of ROS, mitigated the stimulation of oxidative stress, and rectified the antioxidant protein contents of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), superoxide dismutase (SOD)2 and glutathione synthetase (GSS). On the other hand, Nar down-regulated inflammatory gene and protein expression, including interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, HMGB1, high mobility group box 1 protein (HMGB1), cyclo-oxygenase-2 (COX-2), the Toll-like receptor 4 (TLR4)-myeloid differentiation factor 88 (MyD88)-TNF receptor-associated factor 6 (TRAF6) path way and downstream mitogen activated protein kinase (MAPK) phosphorylation, activator protein transcription factor-1 (AP-1) and nuclear factor (NF)-κB. Moroever, Nar markedly attenuated the cytochrome c shift from the mitochondria to the cytosol and regulated caspase-3-related protein expression. To the best of our knowledge, this is the first study to report the antioxidant, anti-inflammatory and anti-apoptotic effects of Nar in neuronal-like PC12 cells. These results suggest that Nar can be utilized as a potential drug for the treatment of neurodegenerative disorders.
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Affiliation(s)
- Hui Wang
- Department of Neurosurgery, Traffic Hospital of Shandong Province, Jinan, Shandong 250031, P.R. China
| | - You Song Xu
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Miao Lin Wang
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Chao Cheng
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Rui Bian
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Hao Yuan
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Yi Wang
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Ting Guo
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Lin Lin Zhu
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
| | - Hang Zhou
- Department of Neurosurgery, The 2nd Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116027, P.R. China
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25
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Turrin NP, Rivest S. Unraveling the Molecular Details Involved in the Intimate Link between the Immune and Neuroendocrine Systems. Exp Biol Med (Maywood) 2016; 229:996-1006. [PMID: 15522835 DOI: 10.1177/153537020422901003] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
During systemic infections, the immune system can signal the brain and act on different neuronal circuits via soluble molecules, such as proinflammatory cytokines, that act on the cells forming the blood-brain barrier and the circumventricular organs. These activated cells release prostaglandin of the E2 type (PGE2), which is the endogenous ligand that triggers the pathways involved in the control of autonomic functions necessary to restore homeostasis and provide inhibitory feedback to innate immunity. Among these neurophysiological functions, activation of the circuits that control the plasma release of glucocorticoids is probably the most critical to the survival of the host in the presence of pathogens. This review revisits this issue and describes in depth the molecular details (including the emerging role of Toll-like receptors during inflammation) underlying the influence of circulating inflammatory molecules on the cerebral tissue, focusing on their contribution in the synthesis and action PGE2 in the brain. We also provide an innovative view supporting the concept of “fast and delayed response” involving the same ligands but different groups of cells, signal transduction pathways, and target genes.
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Affiliation(s)
- Nicolas P Turrin
- Laboratory of Molecular Endocrinology, CHUL Research Center and Department of Anatomy and Physiology, Laval University, 2705 Boulevard Laurier, Québec G1V 4G2, Canada
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26
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Café-Mendes CC, Garay-Malpartida HM, Malta MB, de Sá Lima L, Scavone C, Ferreira ZS, Markus RP, Marcourakis T. Chronic nicotine treatment decreases LPS signaling through NF-κB and TLR-4 modulation in the hippocampus. Neurosci Lett 2016; 636:218-224. [PMID: 27984197 DOI: 10.1016/j.neulet.2016.10.056] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 10/09/2016] [Accepted: 10/20/2016] [Indexed: 01/30/2023]
Abstract
The hippocampus is a brain region that is rich in nicotinic acetylcholine receptors (nAChRs), especially the α7 subtype. The hippocampus is severely affected in disorders that have a neuroinflammatory component, such as Alzheimer's disease, Parkinson's disease, and schizophrenia. Previous studies demonstrated both in vivo and in vitro that nicotine inhibits immunological responses, including those that are triggered by the inflammatory agent lipopolysaccharide (LPS), the endotoxin of Gram-negative bacteria. The present study investigated whether chronically administered nicotine interferes with the nuclear binding of nuclear factor-κB (NF-κB) and the expression of LPS-induced inflammatory response genes. The results indicated that chronic nicotine administration (0.1mg/kg, s.c., 14days) inhibited the LPS-induced nuclear binding of NF-κB and mRNA expression levels of Tnf, Il1b, Nos2, and Tlr4. The presence of both the selective α7 nAChR antagonist methyllycaconitine (MLA; 5.0mg/kg i.p., 14days) and the nonselective nAChR antagonist mecamylamine (Meca; 1.0mg/kg, s.c., 14days) reversed the inhibitory effects of nicotine. These results suggest that the chronic activation of α7- and αxβy-containing nAChRs reduces acute inflammatory responses in the brain.
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Affiliation(s)
- Cecília Cerqueira Café-Mendes
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil; School of Medicine, University of São Paulo, São Paulo, Brazil
| | | | - Marília Brinati Malta
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Larrissa de Sá Lima
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Cristóforo Scavone
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Zulma S Ferreira
- Laboratory of Chronopharmacology, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Regina P Markus
- Laboratory of Chronopharmacology, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Tania Marcourakis
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil.
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Morita-Takemura S, Nakahara K, Tatsumi K, Okuda H, Tanaka T, Isonishi A, Wanaka A. Changes in endothelial cell proliferation and vascular permeability after systemic lipopolysaccharide administration in the subfornical organ. J Neuroimmunol 2016; 298:132-7. [PMID: 27609286 DOI: 10.1016/j.jneuroim.2016.06.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 06/13/2016] [Accepted: 06/28/2016] [Indexed: 01/16/2023]
Abstract
The subfornical organ (SFO) has highly permeable fenestrated vasculature and is a key site for immune-to-brain communications. Recently, we showed the occurrence of continuous angiogenesis in the SFO. In the present study, we found that systemic administration of bacterial lipopolysaccharide (LPS) reduced the vascular permeability and endothelial cell proliferation. In LPS-administered mice, the SFO vasculature showed a significant decrease in the immunoreactivity of plasmalemma vesicle associated protein-1, a marker of endothelial fenestral diaphragms. These data suggest that vasculature undergoes structural change to decrease vascular permeability in response to systemic LPS administration.
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Affiliation(s)
- Shoko Morita-Takemura
- Department of Anatomy & Neuroscience, Faculty of Medicine, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8521, Japan.
| | - Kazuki Nakahara
- Department of Anatomy & Neuroscience, Faculty of Medicine, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8521, Japan
| | - Kouko Tatsumi
- Department of Anatomy & Neuroscience, Faculty of Medicine, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8521, Japan
| | - Hiroaki Okuda
- Department of Anatomy & Neuroscience, Faculty of Medicine, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8521, Japan; Department of Functional Anatomy, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Tatsuhide Tanaka
- Department of Anatomy & Neuroscience, Faculty of Medicine, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8521, Japan
| | - Ayami Isonishi
- Department of Anatomy & Neuroscience, Faculty of Medicine, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8521, Japan
| | - Akio Wanaka
- Department of Anatomy & Neuroscience, Faculty of Medicine, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8521, Japan
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28
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Abstract
Microglia constitute the powerhouse of the innate immune system in the brain. It is now widely accepted that they are monocytic-derived cells that infiltrate the developing brain at the early embryonic stages, and acquire a resting phenotype characterized by the presence of dense branching processes, called ramifications. Microglia use these dynamic ramifications as sentinels to sense and detect any occurring alteration in brain homeostasis. Once a danger signal is detected, such as molecular factors associated to brain damage or infection, they get activated by acquiring a less ramified phenotype, and mount adequate responses that range from phagocyting cell debris to secreting inflammatory and trophic factors. Here, we review the origin of microglia and we summarize the main molecular signals involved in controlling their function under physiological conditions. In addition, their implication in the pathogenesis of multiple sclerosis and stress is discussed.
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Affiliation(s)
- Ayman ElAli
- Neuroscience Laboratory, CHU de Québec Research Center (CHUL), Department of Psychiatry and Neuroscience, Faculty of Medicine, Laval University Quebec, CA, Canada
| | - Serge Rivest
- Neuroscience Laboratory, CHU de Québec Research Center (CHUL), Department of Molecular Medicine, Faculty of Medicine, Laval University Quebec, CA, Canada
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29
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Abstract
The innate immune response is a coordinated set of reactions involving cells of myeloid lineage and a network of signaling molecules. Such a response takes place in the CNS during trauma, stroke, spinal cord injury, and neurodegenerative diseases, suggesting that macrophages/microglia are the cells that perpetuate the progressive neuronal damage. However, there is accumulating evidence that these cells and their secreted proinflammatory molecules have more beneficial effects than detrimental consequences for the neuronal elements. Indeed, a timely controlled innate immune response may limit toxicity in swiftly eliminating foreign materials and debris that are known to interfere with recovery and regeneration. Each step of the immune cascade is under the tight control of stimulatory and inhibitory signals. Glucocorticoids (GCs) act as the critical negative feedback on all myeloid cells, including those present within the brain parenchyma. Because too little is like too much, both an inappropriate feedback of GCs on microglia and high circulating GC levels in stressed individuals have been associated with deleterious consequences for the brain. In this review, the authors discuss both sides of the story with a particular emphasis on the neuro-protective role of endogenous GCs during immune challenges and the problems in determining whether GCs can be a good therapy for the treatment of neuropathological conditions.
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Affiliation(s)
- Isaias Glezer
- Laboratory of Molecular Endocrinology, CHUL Research Center, Department of Anatomy and Physiology, Laval University, Québec, Canada
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30
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TRPV1 is crucial for proinflammatory STAT3 signaling and thermoregulation-associated pathways in the brain during inflammation. Sci Rep 2016; 6:26088. [PMID: 27188969 PMCID: PMC4870621 DOI: 10.1038/srep26088] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 04/25/2016] [Indexed: 01/06/2023] Open
Abstract
Transient receptor potential vanilloid receptor 1 (TRPV1) is a non-selective cation channel that is stimulated by heat (>43 °C), mechanical/osmotic stimuli, and low pH. The importance of TRPV1 in inflammatory responses has been demonstrated, whereas its participation in brains remains unclear. In the present study, the intracerebroventricular (icv) administration of the TRPV1 agonist resiniferatoxin (RTX) induced the activation of signal transducer and activator of transcription 3 (STAT3) in circumventricular organs (CVOs) and thermoregulation-associated brain regions with a similar patttern to the peripheral and icv administration of lipopolysaccharide (LPS). With the peripheral and icv LPS stimuli, STAT3 activation was significantly lower in Trpv1−/− mice than in Trpv1+/+ mice. The icv administration of RTX induced transient hypothermia, whereas that of the TRPV1 antagonist capsazepine enhanced the magnitude and period of LPS-induced hyperthermia. These results indicate that TRPV1 is important for activating proinflammatory STAT3 signaling and thermoregulation-associated brain pathways in the brain.
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31
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Inflammatory transcription factors as activation markers and functional readouts in immune-to-brain communication. Brain Behav Immun 2016; 54:1-14. [PMID: 26348582 DOI: 10.1016/j.bbi.2015.09.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 08/31/2015] [Accepted: 09/04/2015] [Indexed: 02/06/2023] Open
Abstract
Immune-to-brain communication pathways involve humoral mediators, including cytokines, central modulation by neuronal afferents and immune cell trafficking to the brain. During systemic inflammation these pathways contribute to mediating brain-controlled sickness symptoms including fever. Experimentally, activation of these signaling pathways can be mimicked and studied when injecting animals with pathogen associated molecular patterns (PAMPS). One central component of the brain inflammatory response, which leads, for example, to fever induction, is transcriptional activation of brain cells via cytokines and PAMPS. We and others have studied the spatiotemporal activation and the physiological significance of transcription factors for the induction of inflammation within the brain and the manifestation of fever. Evidence has revealed a role of nuclear factor (NF)κB in the initiation, signal transducer and activator of transcription (STAT)3 in the maintenance and NF-interleukin (IL)6 in the maintenance or even termination of brain-inflammation and fever. Moreover, psychological stressors, such as exposure to a novel environment, leads to increased body core temperature and genomic NF-IL6-activation, suggesting a potential use of NF-IL6-immunohistochemistry as a multimodal brain cell activation marker and a role for NF-IL6 for differential brain activity. In addition, the nutritional status, as reflected by circulating levels of the cytokine-like hormone leptin, influence immune-to-brain communication and age-dependent changes in LPS-induced fever. Overall, transcription factors remain therapeutically important targets for the treatment of brain-inflammation and fever induction during infectious/non-infectious inflammatory and psychological stress. However, the exact physiological role and significance of these transcription factors requires to be further investigated.
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32
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Ray R, Juranek JK, Rai V. RAGE axis in neuroinflammation, neurodegeneration and its emerging role in the pathogenesis of amyotrophic lateral sclerosis. Neurosci Biobehav Rev 2015; 62:48-55. [PMID: 26724598 DOI: 10.1016/j.neubiorev.2015.12.006] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Revised: 10/19/2015] [Accepted: 12/10/2015] [Indexed: 12/13/2022]
Abstract
RAGE, the receptor of advanced glycation end-products, is thought to be one of the potential contributors to the neurodegeneration. It has been shown that RAGE activation triggers an increase in proinflammatory molecules, oxidative stressors and cytokines. RAGE involvement has been documented in the pathogenesis of a number of neurodegenerative diseases such amyotrophic lateral sclerosis (ALS), Alzheimer's, Parkinson's, Huntington's, Creutzfeld-Jakob' diseases and various neurodegenerative conditions such as diabetic neuropathy, familial amyloid polyneuropathy, Charcot neuroarthropathy and vasculitic neuropathy. Although the detailed mechanisms of RAGE contribution to the neurodegeneration remains unclear, studies indicate that RAGE detrimental actions are exerted via its binding to the pro-inflammatory ligands such as advanced glycation end-products, S100/calgranulin and amphoterin and subsequent activation of downstream regulatory pathways such as NF-κB, STAT and JKN pathways. Here, in this review we attempt to shed light onto molecular events and pathological pathways involved in neuroinflammation, neurodegeneration and its emerging role in the pathogenesis of amyotrophic lateral sclerosis (ALS)--a progressive and fatal neurodegenerative disorder, summarizing current knowledge and the prospect of RAGE in the pathogenesis of this disastrous disease.
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Affiliation(s)
- Rashmi Ray
- Institute of Life Sciences, Bhubaneswar 751023, India; Manipal University, Karnataka 576104, India
| | - Judyta K Juranek
- Department of Medicine, New York University Medical Center, New York, USA; Department of Pathophysiology, Faculty of Medicine, University of Warmia and Mazury, 10-557 Olsztyn, Poland.
| | - Vivek Rai
- Institute of Life Sciences, Bhubaneswar 751023, India.
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Kaus A, Sareen D. ALS Patient Stem Cells for Unveiling Disease Signatures of Motoneuron Susceptibility: Perspectives on the Deadly Mitochondria, ER Stress and Calcium Triad. Front Cell Neurosci 2015; 9:448. [PMID: 26635528 PMCID: PMC4652136 DOI: 10.3389/fncel.2015.00448] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 11/02/2015] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a largely sporadic progressive neurodegenerative disease affecting upper and lower motoneurons (MNs) whose specific etiology is incompletely understood. Mutations in superoxide dismutase-1 (SOD1), TAR DNA-binding protein 43 (TARDBP/TDP-43) and C9orf72, have been identified in subsets of familial and sporadic patients. Key associated molecular and neuropathological features include ubiquitinated TDP-43 inclusions, stress granules, aggregated dipeptide proteins from mutant C9orf72 transcripts, altered mitochondrial ultrastructure, dysregulated calcium homeostasis, oxidative and endoplasmic reticulum (ER) stress, and an unfolded protein response (UPR). Such impairments have been documented in ALS animal models; however, whether these mechanisms are initiating factors or later consequential events leading to MN vulnerability in ALS patients is debatable. Human induced pluripotent stem cells (iPSCs) are a valuable tool that could resolve this “chicken or egg” causality dilemma. Relevant systems for probing pathophysiologically affected cells from large numbers of ALS patients and discovering phenotypic disease signatures of early MN susceptibility are described. Performing unbiased ‘OMICS and high-throughput screening in relevant neural cells from a cohort of ALS patient iPSCs, and rescuing mitochondrial and ER stress impairments, can identify targeted therapeutics for increasing MN longevity in ALS.
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Affiliation(s)
- Anjoscha Kaus
- Board of Governors-Regenerative Medicine Institute, Cedars-Sinai Medical Center Los Angeles, CA, USA ; Department of Biomedical Sciences, Cedars-Sinai Medical Center Los Angeles, CA, USA
| | - Dhruv Sareen
- Board of Governors-Regenerative Medicine Institute, Cedars-Sinai Medical Center Los Angeles, CA, USA ; Department of Biomedical Sciences, Cedars-Sinai Medical Center Los Angeles, CA, USA ; iPSC Core, The David and Janet Polak Stem Cell Laboratory, Cedars-Sinai Medical Center Los Angeles, CA, USA
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34
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Xavier AL, Menezes JRL, Goldman SA, Nedergaard M. Fine-tuning the central nervous system: microglial modelling of cells and synapses. Philos Trans R Soc Lond B Biol Sci 2015; 369:20130593. [PMID: 25225087 DOI: 10.1098/rstb.2013.0593] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Microglia constitute as much as 10-15% of all cells in the mammalian central nervous system (CNS) and are the only glial cells that do not arise from the neuroectoderm. As the principal CNS immune cells, microglial cells represent the first line of defence in response to exogenous threats. Past studies have largely been dedicated to defining the complex immune functions of microglial cells. However, our understanding of the roles of microglia has expanded radically over the past years. It is now clear that microglia are critically involved in shaping neural circuits in both the developing and adult CNS, and in modulating synaptic transmission in the adult brain. Intriguingly, microglial cells appear to use the same sets of tools, including cytokine and chemokine release as well as phagocytosis, whether modulating neural function or mediating the brain's innate immune responses. This review will discuss recent developments that have broadened our views of neuro-glial signalling to include the contribution of microglial cells.
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Affiliation(s)
- Anna L Xavier
- Laboratório de Neuroanatomia Celular, Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro 21941-902, Brazil Center for Translational Neuromedicine, University of Rochester Medical School, Rochester, NY 14642, USA
| | - João R L Menezes
- Laboratório de Neuroanatomia Celular, Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Steven A Goldman
- Department of Neurosurgery, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, University of Rochester Medical School, Rochester, NY 14642, USA
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35
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Franco R, Fernández-Suárez D. Alternatively activated microglia and macrophages in the central nervous system. Prog Neurobiol 2015; 131:65-86. [PMID: 26067058 DOI: 10.1016/j.pneurobio.2015.05.003] [Citation(s) in RCA: 495] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 05/22/2015] [Accepted: 05/30/2015] [Indexed: 12/20/2022]
Abstract
Macrophages are important players in the fight against viral, bacterial, fungal and parasitic infections. From a resting state they may undertake two activation pathways, the classical known as M1, or the alternative known as M2. M1 markers are mostly mediators of pro-inflammatory responses whereas M2 markers emerge for resolution and cleanup. Microglia exerts in the central nervous system (CNS) a function similar to that of macrophages in the periphery. Microglia activation and proliferation occurs in almost any single pathology affecting the CNS. Often microglia activation has been considered detrimental and drugs able to stop microglia activation were considered for the treatment of a variety of diseases. Cumulative evidence shows that microglia may undergo the alternative activation pathway, express M2-type markers and contribute to neuroprotection. This review focuses on details about the role of M2 microglia and in the approaches available for its identification. Approaches to drive the M2 phenotype and data on its potential in CNS diseases are also reviewed.
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Affiliation(s)
- Rafael Franco
- Molecular Neurobiology Laboratory, Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain; Centro Investigación Biomédica en Red: Enfermedades Neurodegenerativas (CIBERNED), Spain.
| | - Diana Fernández-Suárez
- Division of Molecular Neurobiology, Department of Neuroscience, Karolinska Institute, 17177 Stockholm, Sweden.
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36
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Larochelle A, Bellavance MA, Rivest S. Role of adaptor protein MyD88 in TLR-mediated preconditioning and neuroprotection after acute excitotoxicity. Brain Behav Immun 2015; 46:221-31. [PMID: 25733102 DOI: 10.1016/j.bbi.2015.02.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 02/03/2015] [Accepted: 02/20/2015] [Indexed: 12/18/2022] Open
Abstract
Excitotoxic cell death is a crucial mechanism through which neurodegeneration occurs in numerous pathologies of the central nervous system (CNS), such as Alzheimer's disease, stroke and spinal cord injury. Toll-like receptors (TLRs) are strongly expressed on microglial cells and are key regulators of the innate immune response to neuronal damage. However, it is still unclear whether their stimulation is protective or harmful in excitotoxic contexts. In this study, we demonstrate that systemic administration of lipopolysaccharide (LPS) or Pam3CSK4 24h prior to an intrastriatal injection of kainic acid (KA) significantly protected cortical neurons in the acute phase of injury. Protection could not be detected with the TLR3 ligand poly-IC. Histological analyses revealed that microglia of LPS and Pam3CSK4 pre-conditioned group were primed to react to injury and exhibited a stronger expression of Tnf and Tlr2 mRNA. We also found that mice deficient for MyD88, a critical adaptor protein for most TLR, were more vulnerable than WT mice to KA-induced excitotoxicity at early (12h and 24h) and late (10days) time points. Finally, bone-marrow chimeric mice revealed that MyD88 signaling in CNS resident cells, but not in cells of hematopoietic origin, mediates the protective effect. This study unravels the potential of TLR2 and TLR4 agonists to induce a protective state of preconditioning against KA-mediated excitotoxicity and further highlights the beneficial role of cerebral MyD88 signaling in this context.
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Affiliation(s)
- Antoine Larochelle
- Neuroscience Laboratory, CHU de Québec Research Center and Department of Molecular Medicine, Faculty of Medicine, Laval University, 2705 Laurier Blvd., Québec G1V 4G2, Canada
| | - Marc-André Bellavance
- Neuroscience Laboratory, CHU de Québec Research Center and Department of Molecular Medicine, Faculty of Medicine, Laval University, 2705 Laurier Blvd., Québec G1V 4G2, Canada
| | - Serge Rivest
- Neuroscience Laboratory, CHU de Québec Research Center and Department of Molecular Medicine, Faculty of Medicine, Laval University, 2705 Laurier Blvd., Québec G1V 4G2, Canada.
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Tumor necrosis factor alpha and its receptors in behaviour and neurobiology of adult mice, in the absence of an immune challenge. Behav Brain Res 2015; 290:51-60. [PMID: 25934492 DOI: 10.1016/j.bbr.2015.04.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 04/21/2015] [Accepted: 04/23/2015] [Indexed: 11/21/2022]
Abstract
Tumor necrosis factor alpha (TNF-α) is a vital component of the immune system and CNS. We previously showed that 3-month-old TNF-α and TNF-α receptor knockout mice had impaired cognition, whilst at 12-months-old mice had better cognition. To extend these findings on possible age-dependent TNF-α effects in the brain, we investigated the behaviour of 6-month-old TNF-α knockout mice and their neurobiological correlates. 6-month-old TNF(-/-), TNF-R1(-/-) and TNF-R2(-/-) mice were compared to age-matched WT mice and tested for various behaviours. ELISA hippocampal levels of nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) and qPCR mRNA levels of Tnfa, Tnfr1, Tnfr2, Il10 and Il1β were measured. TNF-R1(-/-) and TNF(-/-) mice were found to have lesser exploratory behaviour than WT mice, while TNF-R1(-/-) mice displayed better memory than WT and TNF-R2(-/-) mice. Both TNF(-/-) and TNF-R2(-/-) mice exhibited significantly lower immobility on the depression test than WT mice. Additionally, TNF(-/-) mice expressed significantly lower levels of BDNF than WT mice in the hippocampus while TNF-R1(-/-) mice displayed significantly lower BDNF levels compared to both WT and TNF-R2(-/-) mice. TNF-R2(-/-) mice also displayed significantly higher levels of NGF compared to TNF-R1(-/-) mice. These results illustrate that TNF-α and its receptors mediate several behavioural phenotypes. Finally, BDNF and NGF levels appear to be regulated by TNF-α and its receptors even under immunologically unchallenged conditions.
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O'Callaghan P, Li JP, Lannfelt L, Lindahl U, Zhang X. Microglial Heparan Sulfate Proteoglycans Facilitate the Cluster-of-Differentiation 14 (CD14)/Toll-like Receptor 4 (TLR4)-Dependent Inflammatory Response. J Biol Chem 2015; 290:14904-14. [PMID: 25869127 DOI: 10.1074/jbc.m114.634337] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Indexed: 11/06/2022] Open
Abstract
Microglia rapidly mount an inflammatory response to pathogens in the central nervous system (CNS). Heparan sulfate proteoglycans (HSPGs) have been attributed various roles in inflammation. To elucidate the relevance of microglial HSPGs in a pro-inflammatory response we isolated microglia from mice overexpressing heparanase (Hpa-tg), the HS-degrading endoglucuronidase, and challenged them with lipopolysaccharide (LPS), a bacterial endotoxin. Prior to LPS-stimulation, the LPS-receptor cluster-of-differentiation 14 (CD14) and Toll-like receptor 4 (TLR4; essential for the LPS response) were similarly expressed in Ctrl and Hpa-tg microglia. However, compared with Ctrl microglia, Hpa-tg cells released significantly less tumor necrosis factor-α (TNFα), essentially failed to up-regulate interleukin-1β (IL1β) and did not initiate synthesis of proCD14. Isolated primary astroyctes expressed TLR4, but notably lacked CD14 and in contrast to microglia, LPS challenge induced a similar TNFα response in Ctrl and Hpa-tg astrocytes, while neither released IL1β. The astrocyte TNFα-induction was thus attributed to CD14-independent TLR4 activation and was unaffected by the cells HS status. Equally, the suppressed LPS-response in Hpa-tg microglia indicated a loss of CD14-dependent TLR4 activation, suggesting that microglial HSPGs facilitate this process. Indeed, confocal microscopy confirmed interactions between microglial HS and CD14 in LPS-stimulated microglia and a potential HS-binding motif in CD14 was identified. We conclude that microglial HSPGs facilitate CD14-dependent TLR4 activation and that heparanase can modulate this mechanism.
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Affiliation(s)
- Paul O'Callaghan
- From the Departments of Medical Cell Biology, Medical Biochemistry and Microbiology, Science for Life Laboratory, and
| | - Jin-Ping Li
- Medical Biochemistry and Microbiology, Science for Life Laboratory, and
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory C11, Uppsala University, Dag Hammarskjölds väg 20, 751 85 Uppsala, Sweden
| | - Ulf Lindahl
- Medical Biochemistry and Microbiology, Science for Life Laboratory, and
| | - Xiao Zhang
- Neuroscience, Uppsala University Biomedical Center, Husargatan 3, 751 23, Uppsala, Sweden and
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Kaut O, Ramirez A, Pieper H, Schmitt I, Jessen F, Wüllner U. DNA methylation of the TNF-α promoter region in peripheral blood monocytes and the cortex of human Alzheimer's disease patients. Dement Geriatr Cogn Disord 2015; 38:10-5. [PMID: 24556805 DOI: 10.1159/000357126] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/16/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The cytokine tumor necrosis factor-alpha (TNF-α) is elevated in the blood of Alzheimer's disease (AD) patients. Epigenetic DNA modifications of the TNF-α promoter may account for the observed upregulation. METHODS We analyzed blood samples of 50 AD patients and 55 controls plus 4 AD and 4 control cortex samples using bisulfite sequencing PCR. RESULTS A significant hypomethylation of the TNF-α promoter was found in AD patients' brains but not in their blood. Cortical TNF-α promoter DNA was higher methylated than blood-derived DNA, both in AD patients and controls. CONCLUSION In AD patients, epigenetic mechanisms of TNF-α gene regulation, like aberrant DNA methylation, are not relevant in blood.
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Affiliation(s)
- Oliver Kaut
- Department of Neurology, University of Bonn, Bonn, Germany
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Kupferschmidt DA, Cody PA, Lovinger DM, Davis MI. Brain BLAQ: Post-hoc thick-section histochemistry for localizing optogenetic constructs in neurons and their distal terminals. Front Neuroanat 2015; 9:6. [PMID: 25698938 PMCID: PMC4316788 DOI: 10.3389/fnana.2015.00006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 01/11/2015] [Indexed: 11/13/2022] Open
Abstract
Optogenetic constructs have revolutionized modern neuroscience, but the ability to accurately and efficiently assess their expression in the brain and associate it with prior functional measures remains a challenge. High-resolution imaging of thick, fixed brain sections would make such post-hoc assessment and association possible; however, thick sections often display autofluorescence that limits their compatibility with fluorescence microscopy. We describe and evaluate a method we call "Brain BLAQ" (Block Lipids and Aldehyde Quench) to rapidly reduce autofluorescence in thick brain sections, enabling efficient axon-level imaging of neurons and their processes in conventional tissue preparations using standard epifluorescence microscopy. Following viral-mediated transduction of optogenetic constructs and fluorescent proteins in mouse cortical pyramidal and dopaminergic neurons, we used BLAQ to assess innervation patterns in the striatum, a region in which autofluorescence often obscures the imaging of fine neural processes. After BLAQ treatment of 250-350 μm-thick brain sections, axons and puncta of labeled afferents were visible throughout the striatum using a standard epifluorescence stereomicroscope. BLAQ histochemistry confirmed that motor cortex (M1) projections preferentially innervated the matrix component of lateral striatum, whereas medial prefrontal cortex projections terminated largely in dorsal striosomes and distinct nucleus accumbens subregions. Ventral tegmental area dopaminergic projections terminated in a similarly heterogeneous pattern within nucleus accumbens and ventral striatum. Using a minimal number of easily manipulated and visualized sections, and microscopes available in most neuroscience laboratories, BLAQ enables simple, high-resolution assessment of virally transduced optogenetic construct expression, and post-hoc association of this expression with molecular markers, physiology and behavior.
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Affiliation(s)
- David A Kupferschmidt
- Section on Synaptic Pharmacology and In Vivo Neural Function, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health Bethesda, MD, USA
| | - Patrick A Cody
- Section on Synaptic Pharmacology and In Vivo Neural Function, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health Bethesda, MD, USA
| | - David M Lovinger
- Section on Synaptic Pharmacology and In Vivo Neural Function, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health Bethesda, MD, USA
| | - Margaret I Davis
- Section on Synaptic Pharmacology and In Vivo Neural Function, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health Bethesda, MD, USA
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Vascular endothelial growth factor-dependent angiogenesis and dynamic vascular plasticity in the sensory circumventricular organs of adult mouse brain. Cell Tissue Res 2015; 359:865-84. [DOI: 10.1007/s00441-014-2080-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 11/25/2014] [Indexed: 12/11/2022]
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42
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Camara ML, Corrigan F, Jaehne EJ, Jawahar MC, Anscomb H, Baune BT. Effects of centrally administered etanercept on behavior, microglia, and astrocytes in mice following a peripheral immune challenge. Neuropsychopharmacology 2015; 40:502-12. [PMID: 25103178 PMCID: PMC4443965 DOI: 10.1038/npp.2014.199] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 07/22/2014] [Accepted: 07/31/2014] [Indexed: 12/13/2022]
Abstract
Peripheral cytokines affect central nervous system (CNS) function, manifesting in symptoms of anxiety and cognitive decline. Although the peripheral blockage of tumor necrosis factor (TNF)-α has been effective in alleviating depression and rheumatoid arthritis, it is yet unknown whether central blockade of TNF-α is beneficial for immune-challenged CNS function. This study investigated the effects of central etanercept administration following a peripheral immune challenge on anxiety-like and cognition-like behaviors and microglia and astrocyte numbers. Twelve-week-old C57BL/6 mice (n=40) were treated with either LPS or saline administered peripherally 24 h before being treated with either etanercept or artificial CSF (aCSF) by intracerebroventricular injection. Mice underwent behavioral analyses for locomotion, memory, and anxiety-like behavior 24 h post-etanercept/aCSF treatment, and tissue was collected to estimate the numbers of hippocampal microglia and astrocytes. Following peripheral immune challenge with LPS, mice showed increased anxiety-like behavior, which was significantly improved following treatment with etanercept (two-way ANOVA: Interaction: F(1,30)=0.60, P=0.44; Saline/LPS challenge: F(1,30)=23.92, P<0.0001, etanercept vs aCSF: F(1,30)=11.09, P=0.0023). For cognition, a significant interaction effect found by two-way ANOVA (Interaction: F(1,20)=4.96, P=0.037, Saline/LPS challenge: F(1,20)=4.966, P=0.31, aCSF/etanercept treatment: F(1,20)=0.06, P=0.80) and post-hoc analysis revealed a significant decrease in cognition in LPS-aCSF compared with Sal-aCSF mice (P=0.038), but no significant difference was noted between LPS-aCSF and LPS-Etan mice (P>0.9). A significant reduction in the number of microglia within the hippocampus of these mice was noted (two-way ANOVA: Interaction: F(1,15)=11.41, P=0.0041; Saline/LPS challenge: F(1,15)=50.13, P<0.0001, etanercept vs aCSF: F(1,15)=3.36, P=0.08). Centrally administered etanercept improved anxiety-like behavior but not spatial memory under a peripheral immune challenge and was associated with a decrease in the hippocampal microglia numbers. This suggests that etanercept recovers anxiety-like behavior possibly mediated by a reduction of TNF-α-related central inflammation.
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Affiliation(s)
- Marie lou Camara
- Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA, Australia,Discipline of Anatomy, School of Medicine, James Cook University, Townsville QLD, Australia
| | - Frances Corrigan
- Discipline of Anatomy and Pathology, School of Medical Sciences, University of Adelaide, SA, Australia
| | - Emily J Jaehne
- Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA, Australia
| | - Magdalene C Jawahar
- Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA, Australia
| | - Helen Anscomb
- Discipline of Anatomy, School of Medicine, James Cook University, Townsville QLD, Australia
| | - Bernhard T Baune
- Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA, Australia,Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA 5005 Australia, Tel: +1 61 8 8222 5141, Fax: +1 61 8 8222 2774, E-mail:
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43
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Stein DG, Geddes RI, Sribnick EA. Recent developments in clinical trials for the treatment of traumatic brain injury. HANDBOOK OF CLINICAL NEUROLOGY 2015; 127:433-51. [PMID: 25702233 DOI: 10.1016/b978-0-444-52892-6.00028-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The clinical understanding of traumatic brain injury (TBI) and its manifestations is beginning to change. Both clinicians and research scientists are recognizing that TBI and related disorders such as stroke are complex, systemic inflammatory and degenerative diseases that require an approach to treatment more sophisticated than targeting a single gene, receptor, or signaling pathway. It is becoming increasingly clear that TBI is a form of degenerative disorder affecting the brain and other organs, and that its manifestations can unfold days, weeks, and years after the initial damage. Until recently, and despite numerous industry- and government-sponsored clinical trials, attempts to find a safe and effective neuroprotective agent have all failed - probably because the research and development strategies have been based on an outdated early 20th century paradigm seeking a magic bullet that will affect a narrowly circumscribed target. We propose that more attention be given to the development of drugs, given alone or in combination, that are pleiotropic in their actions and that have systemic as well as central nervous system effects. We review current Phase II and Phase III trials for acute pharmacologic treatments for TBI and report on their aims, methods, status, and important associated research issues.
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Affiliation(s)
- Donald G Stein
- Department of Emergency Medicine, Emory University School of Medicine, Atlanta, GA, USA.
| | - Rastafa I Geddes
- Department of Emergency Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Eric A Sribnick
- Department of Emergency Medicine, Emory University School of Medicine, Atlanta, GA, USA
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44
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Nakano Y, Furube E, Morita S, Wanaka A, Nakashima T, Miyata S. Astrocytic TLR4 expression and LPS-induced nuclear translocation of STAT3 in the sensory circumventricular organs of adult mouse brain. J Neuroimmunol 2015; 278:144-58. [DOI: 10.1016/j.jneuroim.2014.12.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 12/13/2014] [Accepted: 12/13/2014] [Indexed: 12/26/2022]
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45
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Izadpanah K, Freyer D, Weber JR, Braun JS. Brain parenchymal TNF-α and IL-1β induction in experimental pneumococcal meningitis. J Neuroimmunol 2014; 276:104-11. [PMID: 25218213 DOI: 10.1016/j.jneuroim.2014.08.625] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 08/23/2014] [Accepted: 08/26/2014] [Indexed: 10/24/2022]
Abstract
Triggers of brain inflammation in pneumococcal meningitis are unknown. TNF-α and IL-1β were upregulated (real time PCR and in situ hybridization) in neurons and astrocytes time-dependently and maximally in the hippocampus during murine pneumococcal meningitis. Upregulation of TNF-α and IL-1β mRNA in the brain parenchyma was independent of cerebrospinal fluid leukocytosis, pneumococcal pneumolysin and H2O2, but it was potently induced by pneumococcal cell wall (PCW) fragments. Brain TNF-α mRNA was downregulated by a matrix metalloproteinases inhibitor. PCW fragments were located in the brain parenchyma. In conclusion, PCW fragments and matrix metalloproteinases trigger cytokine induction in the brain parenchyma during pneumococcal meningitis.
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Affiliation(s)
- Kaywan Izadpanah
- Department of Neurology, Charité Universitätsmedizin Berlin, Germany; Department of Orthopedics and Traumatology, University Freiburg, Germany
| | - Dorette Freyer
- Department of Neurology, Charité Universitätsmedizin Berlin, Germany
| | - Joerg R Weber
- Department of Neurology, Charité Universitätsmedizin Berlin, Germany; Department of Neurology, Klinikum Klagenfurt, Austria
| | - Johann S Braun
- Department of Neurology, Charité Universitätsmedizin Berlin, Germany; Department of Internal Medicine, Division Neurology, College of Medicine and Health Sciences, United Arab Emirates University, United Arab Emirates.
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Wochal P, Rathinam VAK, Dunne A, Carlson T, Kuang W, Seidl KJ, Hall JP, Lin LL, Collins M, Schattgen SA, MacKay CR, Fagundes CT, Carpenter S, Fitzgerald KA, O'Neill LAJ. TRIL is involved in cytokine production in the brain following Escherichia coli infection. THE JOURNAL OF IMMUNOLOGY 2014; 193:1911-9. [PMID: 25015823 DOI: 10.4049/jimmunol.1302392] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
TLR4 interactor with leucine-rich repeats (TRIL) is a brain-enriched accessory protein that is important in TLR3 and TLR4 signaling. In this study, we generated Tril(-/-) mice and examined TLR responses in vitro and in vivo. We found a role for TRIL in both TLR4 and TLR3 signaling in mixed glial cells, consistent with the high level of expression of TRIL in these cells. We also found that TRIL is a modulator of the innate immune response to LPS challenge and Escherichia coli infection in vivo. Tril(-/-) mice produce lower levels of multiple proinflammatory cytokines and chemokines specifically within the brain after E. coli and LPS challenge. Collectively, these data uncover TRIL as a mediator of innate immune responses within the brain, where it enhances neuronal cytokine responses to infection.
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Affiliation(s)
- Paulina Wochal
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Vijay A K Rathinam
- Division of Infectious Disease and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Aisling Dunne
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Thaddeus Carlson
- Inflammation and Immunology Research Unit, Pfizer, Cambridge, MA 02140; and
| | - Wen Kuang
- Global Biotherapeutic Technologies, Pfizer, Andover, MA 01810
| | - Katherine J Seidl
- Inflammation and Immunology Research Unit, Pfizer, Cambridge, MA 02140; and
| | - J Perry Hall
- Inflammation and Immunology Research Unit, Pfizer, Cambridge, MA 02140; and
| | - Lih-Ling Lin
- Inflammation and Immunology Research Unit, Pfizer, Cambridge, MA 02140; and
| | - Mary Collins
- Inflammation and Immunology Research Unit, Pfizer, Cambridge, MA 02140; and
| | - Stefan A Schattgen
- Division of Infectious Disease and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Christopher R MacKay
- Division of Infectious Disease and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Caio T Fagundes
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Susan Carpenter
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; Division of Infectious Disease and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Katherine A Fitzgerald
- Division of Infectious Disease and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Luke A J O'Neill
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland;
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Qingkailing Suppresses the Activation of BV2 Microglial Cells by Inhibiting Hypoxia/Reoxygenation-Induced Inflammatory Responses. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 2014:696218. [PMID: 24864157 PMCID: PMC4020462 DOI: 10.1155/2014/696218] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 04/02/2014] [Indexed: 11/18/2022]
Abstract
Qingkailing (QKL) is a well-known composite extract used in traditional Chinese medicine. This extract has been extensively administered to treat the acute phase of cerebrovascular disease. Our previous experiments confirmed that QKL exerts an inhibitory effect on cerebral ischemia-induced inflammatory responses. However, whether QKL suppresses the activation of microglia, the primary resident immune cells in the brain, has yet to be determined. In this study, BV2 microglial cells were used to validate the protective effects of QKL treatment following ischemia-reperfusion injury simulated via hypoxia/reoxygenation in vitro. Under these conditions, high expression levels of ROS, COX-2, iNOS, and p-p38 protein were detected. Following ischemia/reperfusion injury, QKL significantly increased the activity of BV2 cells to approximately the basal level by modulating microglial activation via inhibition of inflammatory factors, including TNF- α , COX-2, iNOS, and p-p38. However, QKL treatment also displayed dose-dependent differences in its inhibitory effects on p38 phosphorylation and inflammatory factor expression.
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48
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Hauser KF, Knapp PE. Interactions of HIV and drugs of abuse: the importance of glia, neural progenitors, and host genetic factors. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2014; 118:231-313. [PMID: 25175867 PMCID: PMC4304845 DOI: 10.1016/b978-0-12-801284-0.00009-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Considerable insight has been gained into the comorbid, interactive effects of HIV and drug abuse in the brain using experimental models. This review, which considers opiates, methamphetamine, and cocaine, emphasizes the importance of host genetics and glial plasticity in driving the pathogenic neuron remodeling underlying neuro-acquired immunodeficiency syndrome and drug abuse comorbidity. Clinical findings are less concordant than experimental work, and the response of individuals to HIV and to drug abuse can vary tremendously. Host-genetic variability is important in determining viral tropism, neuropathogenesis, drug responses, and addictive behavior. However, genetic differences alone cannot account for individual variability in the brain "connectome." Environment and experience are critical determinants in the evolution of synaptic circuitry throughout life. Neurons and glia both exercise control over determinants of synaptic plasticity that are disrupted by HIV and drug abuse. Perivascular macrophages, microglia, and to a lesser extent astroglia can harbor the infection. Uninfected bystanders, especially astroglia, propagate and amplify inflammatory signals. Drug abuse by itself derails neuronal and glial function, and the outcome of chronic exposure is maladaptive plasticity. The negative consequences of coexposure to HIV and drug abuse are determined by numerous factors including genetics, sex, age, and multidrug exposure. Glia and some neurons are generated throughout life, and their progenitors appear to be targets of HIV and opiates/psychostimulants. The chronic nature of HIV and drug abuse appears to result in sustained alterations in the maturation and fate of neural progenitors, which may affect the balance of glial populations within multiple brain regions.
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Affiliation(s)
- Kurt F Hauser
- Department of Pharmacology & Toxicology, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia, USA.
| | - Pamela E Knapp
- Department of Pharmacology & Toxicology, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia, USA; Department of Anatomy & Neurobiology, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia, USA
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Pękalski J, Zuk PJ, Kochańczyk M, Junkin M, Kellogg R, Tay S, Lipniacki T. Spontaneous NF-κB activation by autocrine TNFα signaling: a computational analysis. PLoS One 2013; 8:e78887. [PMID: 24324544 PMCID: PMC3855823 DOI: 10.1371/journal.pone.0078887] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 09/16/2013] [Indexed: 11/18/2022] Open
Abstract
NF-κB is a key transcription factor that regulates innate immune response. Its activity is tightly controlled by numerous feedback loops, including two negative loops mediated by NF-κB inducible inhibitors, IκBα and A20, which assure oscillatory responses, and by positive feedback loops arising due to the paracrine and autocrine regulation via TNFα, IL-1 and other cytokines. We study the NF-κB system of interlinked negative and positive feedback loops, combining bifurcation analysis of the deterministic approximation with stochastic numerical modeling. Positive feedback assures the existence of limit cycle oscillations in unstimulated wild-type cells and introduces bistability in A20-deficient cells. We demonstrated that cells of significant autocrine potential, i.e., cells characterized by high secretion of TNFα and its receptor TNFR1, may exhibit sustained cytoplasmic-nuclear NF-κB oscillations which start spontaneously due to stochastic fluctuations. In A20-deficient cells even a small TNFα expression rate qualitatively influences system kinetics, leading to long-lasting NF-κB activation in response to a short-pulsed TNFα stimulation. As a consequence, cells with impaired A20 expression or increased TNFα secretion rate are expected to have elevated NF-κB activity even in the absence of stimulation. This may lead to chronic inflammation and promote cancer due to the persistent activation of antiapoptotic genes induced by NF-κB. There is growing evidence that A20 mutations correlate with several types of lymphomas and elevated TNFα secretion is characteristic of many cancers. Interestingly, A20 loss or dysfunction also leaves the organism vulnerable to septic shock and massive apoptosis triggered by the uncontrolled TNFα secretion, which at high levels overcomes the antiapoptotic action of NF-κB. It is thus tempting to speculate that some cancers of deregulated NF-κB signaling may be prone to the pathogen-induced apoptosis.
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Affiliation(s)
- Jakub Pękalski
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
| | - Pawel J. Zuk
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
- Institute of Theoretical Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland
| | - Marek Kochańczyk
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
| | - Michael Junkin
- Department of Biosystems Science and Engineering, ETH Zurich, Zurich, Switzerland
| | - Ryan Kellogg
- Department of Biosystems Science and Engineering, ETH Zurich, Zurich, Switzerland
| | - Savaş Tay
- Department of Biosystems Science and Engineering, ETH Zurich, Zurich, Switzerland
| | - Tomasz Lipniacki
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
- Department of Statistics, Rice University, Houston, Texas, United States of America
- * E-mail:
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Teocchi MA, Ferreira AÉD, da Luz de Oliveira EP, Tedeschi H, D'Souza-Li L. Hippocampal gene expression dysregulation of Klotho, nuclear factor kappa B and tumor necrosis factor in temporal lobe epilepsy patients. J Neuroinflammation 2013; 10:53. [PMID: 23634661 PMCID: PMC3651326 DOI: 10.1186/1742-2094-10-53] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Accepted: 03/19/2013] [Indexed: 12/12/2022] Open
Abstract
Background Previous research in animal seizure models indicates that the pleiotropic cytokine TNF is an important effector/mediator of neuroinflammation and cell death. Recently, it has been demonstrated that TNF downregulates Klotho (KL) through the nuclear factor kappa B (NFkB) system in animal models of chronic kidney disease and colitis. KL function in the brain is unclear, although Klotho knockout (Kl−/−) mice exhibit neural degeneration and a reduction of hippocampal synapses. Our aim was to verify if the triad KL-NFKB1-TNF is also dysregulated in temporal lobe epilepsy associated with hippocampal sclerosis (TLE(HS)) patients. Findings We evaluated TNF, NFKB1 and KL relative mRNA expression levels by reverse transcription quantitative PCR (RT-qPCR) in resected hippocampal tissue samples from 14 TLE(HS) patients and compared them to five post mortem controls. Four reference genes were used: GAPDH, HPRT1, ENO2 and TBP. We found that TNF expression was dramatically upregulated in TLE(HS) patients (P <0.005). NFKB1 expression was also increased (P <0.03) while KL was significantly downregulated (P <0.03) in TLE(HS) patients. Hippocampal KL expression had an inverse correlation with NFKB1 and TNF. Conclusions Our data suggest that, similar to other inflammatory diseases, TNF downregulates KL through NFkB in TLE(HS) patients. The remarkable TNF upregulation in patients is a strong indication of hippocampal chronic inflammation. Our finding of hippocampal KL downregulation has wide implications not only for TLE(HS) but also for other neuronal disorders related to neurodegeneration associated with inflammation.
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Affiliation(s)
- Marcelo Ananias Teocchi
- Laboratory of Pediatric Endocrinology, Center for Investigation in Pediatrics, University of Campinas, PO Box 6111, Campinas, SP 13083-970, Brazil
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