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Chiba N, Tada R, Ohnishi T, Matsuguchi T. TLR4/7-mediated host-defense responses of gingival epithelial cells. J Cell Biochem 2024; 125:e30576. [PMID: 38726711 DOI: 10.1002/jcb.30576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 04/18/2024] [Accepted: 04/25/2024] [Indexed: 07/12/2024]
Abstract
Gingival epithelial cells (GECs) are physical and immunological barriers against outward pathogens while coping with a plethora of non-pathogenic commensal bacteria. GECs express several members of Toll-like receptors (TLRs) and control subsequent innate immune responses. TLR4 senses lipopolysaccharide (LPS) while TLR7/8 recognizes single-strand RNA (ssRNA) playing important roles against viral infection. However, their distinct roles in GECs have not been fully demonstrated. Here, we analyzed biological responses of GECs to LPS and CL075, a TLR7/8 agonist. GE1, a mouse gingival epithelial cell line, constitutively express TLR4 and TLR7, but not TLR8, like primary skin keratinocytes. Stimulation of GE1 cells with CL075 induced cytokine, chemokine, and antimicrobial peptide expressions, the pattern of which is rather different from that with LPS: higher mRNA levels of interferon (IFN) β, CXCL10, and β-defensin (BD) 14 (mouse homolog of human BD3); lower levels of tumor necrosis factor (TNF), CCL5, CCL11, CCL20, CXCL2, and CX3CL1. As for the intracellular signal transduction of GE1 cells, CL075 rapidly induced significant AKT phosphorylation but failed to activate IKKα/β-NFκB pathway, whereas LPS induced marked IKKα/β-NFκB activation without significant AKT phosphorylation. In contrast, both CL075 and LPS induced rapid IKKα/β-NFκB activation and AKT phosphorylation in a macrophage cell line. Furthermore, specific inhibition of AKT activity abrogated CL075-induced IFNβ, CXCL10, and BD14 mRNA expression in GE1 cells. Thus, TLR4/7 ligands appear to induce rather different host-defense responses of GECs through distinct intracellular signaling mechanisms.
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Affiliation(s)
- Norika Chiba
- Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Ryohei Tada
- Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
- Department of Oral and Maxillofacial Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Tomokazu Ohnishi
- Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Tetsuya Matsuguchi
- Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
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2
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Liu J, Copland DA, Clare AJ, Gorski M, Richards BT, Scott L, Theodoropoulou S, Greferath U, Cox K, Shi G, Bell OH, Ou K, Powell JLB, Wu J, Robles LM, Li Y, Nicholson LB, Coffey PJ, Fletcher EL, Guymer R, Radeke MJ, Heid IM, Hageman GS, Chan YK, Dick AD. Replenishing IRAK-M expression in retinal pigment epithelium attenuates outer retinal degeneration. Sci Transl Med 2024; 16:eadi4125. [PMID: 38838135 DOI: 10.1126/scitranslmed.adi4125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 05/14/2024] [Indexed: 06/07/2024]
Abstract
Chronic inflammation is a constitutive component of many age-related diseases, including age-related macular degeneration (AMD). Here, we identified interleukin-1 receptor-associated kinase M (IRAK-M) as a key immunoregulator in retinal pigment epithelium (RPE) that declines during the aging process. Rare genetic variants of IRAK3, which encodes IRAK-M, were associated with an increased likelihood of developing AMD. In human samples and mouse models, IRAK-M abundance in the RPE declined with advancing age or exposure to oxidative stress and was further reduced in AMD. Irak3-knockout mice exhibited an increased incidence of outer retinal degeneration at earlier ages, which was further exacerbated by oxidative stressors. The absence of IRAK-M led to a disruption in RPE cell homeostasis, characterized by compromised mitochondrial function, cellular senescence, and aberrant cytokine production. IRAK-M overexpression protected RPE cells against oxidative or immune stressors. Subretinal delivery of adeno-associated virus (AAV)-expressing human IRAK3 rescued light-induced outer retinal degeneration in wild-type mice and attenuated age-related spontaneous retinal degeneration in Irak3-knockout mice. Our data show that replenishment of IRAK-M in the RPE may redress dysregulated pro-inflammatory processes in AMD, suggesting a potential treatment for retinal degeneration.
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Affiliation(s)
- Jian Liu
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - David A Copland
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Alison J Clare
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Mathias Gorski
- Department of Genetic Epidemiology, University of Regensburg, Regensburg 93053, Germany
| | - Burt T Richards
- Sharon Eccles Steele Center for Translational Medicine, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Louis Scott
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Sofia Theodoropoulou
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Ursula Greferath
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Katherine Cox
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Gongyu Shi
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Oliver H Bell
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Kepeng Ou
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Jenna Le Brun Powell
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Jiahui Wu
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Luis Martinez Robles
- School of Cellular and Molecular Medicine, University of Bristol, Bristol BS8 1TD, UK
| | - Yingxin Li
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
| | - Lindsay B Nicholson
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
- School of Cellular and Molecular Medicine, University of Bristol, Bristol BS8 1TD, UK
| | - Peter J Coffey
- Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Erica L Fletcher
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Robyn Guymer
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Monte J Radeke
- Neuroscience Research Institute, University of California, Santa Barbara, CA 93106, USA
| | - Iris M Heid
- Department of Genetic Epidemiology, University of Regensburg, Regensburg 93053, Germany
| | - Gregory S Hageman
- Sharon Eccles Steele Center for Translational Medicine, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Ying Kai Chan
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02215, USA
| | - Andrew D Dick
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol BS8 1TD, UK
- School of Cellular and Molecular Medicine, University of Bristol, Bristol BS8 1TD, UK
- Institute of Ophthalmology, University College London, London EC1V 9EL, UK
- National Institute for Health Research Biomedical Research Centre, Moorfields Eye Hospital, London EC1V 2PD, UK
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3
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Dorrity TJ, Shin H, Gertie JA, Chung H. The Sixth Sense: Self-nucleic acid sensing in the brain. Adv Immunol 2024; 161:53-83. [PMID: 38763702 PMCID: PMC11186578 DOI: 10.1016/bs.ai.2024.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2024]
Abstract
Our innate immune system uses pattern recognition receptors (PRRs) as a first line of defense to detect microbial ligands and initiate an immune response. Viral nucleic acids are key ligands for the activation of many PRRs and the induction of downstream inflammatory and antiviral effects. Initially it was thought that endogenous (self) nucleic acids rarely activated these PRRs, however emerging evidence indicates that endogenous nucleic acids are able to activate host PRRs in homeostasis and disease. In fact, many regulatory mechanisms are in place to finely control and regulate sensing of self-nucleic acids by PRRs. Sensing of self-nucleic acids is particularly important in the brain, as perturbations to nucleic acid sensing commonly leads to neuropathology. This review will highlight the role of nucleic acid sensors in the brain, both in disease and homeostasis. We also indicate the source of endogenous stimulatory nucleic acids where known and summarize future directions for the study of this growing field.
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Key Words
- Brain
- DNA sensing PRRs: cGAS, AIM2, TLR9
- Neurodegeneration: Aicardi-Goutieres syndrome (AGS), Alzheimer's disease, Amyotrophic lateral sclerosis, Stroke, Traumatic brain injury
- Neurodevelopment
- Neuroinflammation
- Nuecleic acid immunity
- Pattern recognition receptors (PRRs)
- RNA sensing PRRs: MDA5, RIG-I, PKR, TLR3, TLR7/8
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Affiliation(s)
- Tyler J Dorrity
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, United States
| | - Heegwon Shin
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, United States
| | - Jake A Gertie
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, United States; Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States; Medical Scientist Training Program, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States
| | - Hachung Chung
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, United States.
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Weickert TW, Ji E, Galletly C, Boerrigter D, Morishima Y, Bruggemann J, Balzan R, O’Donnell M, Liu D, Lenroot R, Weickert CS, Kindler J. Toll-Like Receptor mRNA Levels in Schizophrenia: Association With Complement Factors and Cingulate Gyrus Cortical Thinning. Schizophr Bull 2024; 50:403-417. [PMID: 38102721 PMCID: PMC10919782 DOI: 10.1093/schbul/sbad171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
BACKGROUND AND HYPOTHESES Previous studies revealed innate immune system activation in people with schizophrenia (SZ), potentially mediated by endogenous pathogen recognition receptors, notably Toll-like receptors (TLR). TLRs are activated by pathogenic molecules like bacterial lipopolysaccharides (TLR1 and TLR4), viral RNA (TLR3), or both (TLR8). Furthermore, the complement system, another key component of innate immunity, has previously been linked to SZ. STUDY DESIGN Peripheral mRNA levels of TLR1, TLR3, TLR4, and TLR8 were compared between SZ and healthy controls (HC). We investigated their relationship with immune activation through complement expression and cortical thickness of the cingulate gyrus, a region susceptible to immunological hits. TLR mRNA levels and peripheral complement receptor mRNA were extracted from 86 SZ and 77 HC white blood cells; structural MRI scans were conducted on a subset. STUDY RESULTS We found significantly higher TLR4 and TLR8 mRNA levels and lower TLR3 mRNA levels in SZ compared to HC. TLRs and complemental factors were significantly associated in SZ and HC, with the strongest deviations of TLR mRNA levels in the SZ subgroup having elevated complement expression. Cortical thickness of the cingulate gyrus was inversely associated with TLR8 mRNA levels in SZ, and with TLR4 and TLR8 levels in HC. CONCLUSIONS The study underscores the role of innate immune activation in schizophrenia, indicating a coordinated immune response of TLRs and the complement system. Our results suggest there could be more bacterial influence (based on TLR 4 levels) as opposed to viral influence (based on TLR3 levels) in schizophrenia. Specific TLRs were associated with brain cortical thickness reductions of limbic brain structures.
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Affiliation(s)
- Thomas W Weickert
- Neuroscience Research Australia, Schizophrenia Research Institute, Randwick, NSW 2031, Australia
- School of Psychiatry, University of New South Wales, Randwick, NSW 2031Australia
- Department of Neuroscience and Physiology, Upstate Medical University, Syracuse, NY 13210, USA
| | - Ellen Ji
- Psychiatric University Hospital Zurich, Zurich, Switzerland
- Neuroscience Research Australia, Sydney, NSW, Australia
| | - Cherrie Galletly
- Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA, Australia
- Ramsay Health Care (SA) Mental Health, Adelaide, Australia
- Northern Adelaide Local Health Network, Adelaide, SA, Australia
| | - Danny Boerrigter
- Neuroscience Research Australia, Schizophrenia Research Institute, Randwick, NSW 2031, Australia
| | - Yosuke Morishima
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland
| | - Jason Bruggemann
- Neuroscience Research Australia, Schizophrenia Research Institute, Randwick, NSW 2031, Australia
- School of Psychiatry, University of New South Wales, Randwick, NSW 2031Australia
- Edith Collins Centre (Translational Research in Alcohol Drugs and Toxicology), Sydney Local Health District, Sydney, Australia
- Speciality of Addiction Medicine, Central Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | - Ryan Balzan
- School of Psychology, Flinders University, Adelaide, SA, Australia
| | - Maryanne O’Donnell
- Neuroscience Research Australia, Schizophrenia Research Institute, Randwick, NSW 2031, Australia
- Kiloh Centre, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Dennis Liu
- Discipline of Psychiatry, School of Medicine, University of Adelaide, Adelaide, SA, Australia
- Ramsay Health Care (SA) Mental Health, Adelaide, Australia
- Northern Adelaide Local Health Network, Adelaide, SA, Australia
| | - Rhoshel Lenroot
- Neuroscience Research Australia, Schizophrenia Research Institute, Randwick, NSW 2031, Australia
- School of Psychiatry, University of New South Wales, Randwick, NSW 2031Australia
- Department of Psychiatry, University of New Mexico, Albuquerque, NM 87131-0001, USA
| | - Cynthia Shannon Weickert
- Neuroscience Research Australia, Schizophrenia Research Institute, Randwick, NSW 2031, Australia
- School of Psychiatry, University of New South Wales, Randwick, NSW 2031Australia
- Department of Neuroscience and Physiology, Upstate Medical University, Syracuse, NY 13210, USA
| | - Jochen Kindler
- Neuroscience Research Australia, Schizophrenia Research Institute, Randwick, NSW 2031, Australia
- University Hospital of Child and Adolescent Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland
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Meißner R, Mokgokong P, Pretorius C, Winter S, Labuschagne K, Kotze A, Prost S, Horin P, Dalton D, Burger PA. Diversity of selected toll-like receptor genes in cheetahs (Acinonyx jubatus) and African leopards (Panthera pardus pardus). Sci Rep 2024; 14:3756. [PMID: 38355905 PMCID: PMC10866938 DOI: 10.1038/s41598-024-54076-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 02/08/2024] [Indexed: 02/16/2024] Open
Abstract
The anthropogenic impact on wildlife is ever increasing. With shrinking habitats, wild populations are being pushed to co-exist in proximity to humans leading to an increased threat of infectious diseases. Therefore, understanding the immune system of a species is key to assess its resilience in a changing environment. The innate immune system (IIS) is the body's first line of defense against pathogens. High variability in IIS genes, like toll-like receptor (TLR) genes, appears to be associated with resistance to infectious diseases. However, few studies have investigated diversity in TLR genes in vulnerable species for conservation. Large predators are threatened globally including leopards and cheetahs, both listed as 'vulnerable' by IUCN. To examine IIS diversity in these sympatric species, we used next-generation-sequencing to compare selected TLR genes in African leopards and cheetahs. Despite differences, both species show some TLR haplotype similarity. Historic cheetahs from all subspecies exhibit greater genetic diversity than modern Southern African cheetahs. The diversity in investigated TLR genes is lower in modern Southern African cheetahs than in African leopards. Compared to historic cheetah data and other subspecies, a more recent population decline might explain the observed genetic impoverishment of TLR genes in modern Southern African cheetahs. However, this may not yet impact the health of this cheetah subspecies.
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Affiliation(s)
- René Meißner
- Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstraße 1, 1160, Vienna, Austria
| | - Prudent Mokgokong
- South African National Biodiversity Institute, National Zoological Garden, 232 Boom Street, Pretoria, 0002, South Africa
| | - Chantelle Pretorius
- South African National Biodiversity Institute, National Zoological Garden, 232 Boom Street, Pretoria, 0002, South Africa
- WWF South African, Bridge House, Boundary Terraces, Mariendahl Ave, Newlands, 7725, Capetown, South Africa
| | - Sven Winter
- Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstraße 1, 1160, Vienna, Austria
| | - Kim Labuschagne
- South African National Biodiversity Institute, National Zoological Garden, 232 Boom Street, Pretoria, 0002, South Africa
| | - Antoinette Kotze
- South African National Biodiversity Institute, National Zoological Garden, 232 Boom Street, Pretoria, 0002, South Africa
- University of the Free State, Bloemfontein Campus, Bloemfontein, 9300, South Africa
| | - Stefan Prost
- South African National Biodiversity Institute, National Zoological Garden, 232 Boom Street, Pretoria, 0002, South Africa
- University of Oulu, Pentti Kaiteran Katu 1, 90570, Oulu, Finland
| | - Petr Horin
- Department of Animal Genetics, University of Veterinary Sciences, Brno, Czech Republic
- Central European Institute of Technology, University of Veterinary Sciences Brno (CEITEC Vetuni), Brno, Czech Republic
| | - Desire Dalton
- South African National Biodiversity Institute, National Zoological Garden, 232 Boom Street, Pretoria, 0002, South Africa.
- School of Health and Life Science, Teesside University, Middlesbrough, Tees Valley, TS1 3BX, UK.
| | - Pamela A Burger
- Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstraße 1, 1160, Vienna, Austria.
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Liu J, Copland DA, Clare AJ, Gorski M, Richards BT, Scott L, Theodoropoulou S, Greferath U, Cox K, Bell OH, Ou K, Powell JLB, Wu J, Robles LM, Li Y, Nicholson LB, Coffey PJ, Fletcher EL, Guymer R, Radeke MJ, Heid IM, Hageman GS, Chan YK, Dick AD. Replenishing Age-Related Decline of IRAK-M Expression in Retinal Pigment Epithelium Attenuates Outer Retinal Degeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.27.559733. [PMID: 37808640 PMCID: PMC10557650 DOI: 10.1101/2023.09.27.559733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Unchecked, chronic inflammation is a constitutive component of age-related diseases, including age-related macular degeneration (AMD). Here we identified interleukin-1 receptor-associated kinase (IRAK)-M as a key immunoregulator in retinal pigment epithelium (RPE) that declines with age. Rare genetic variants of IRAK-M increased the likelihood of AMD. IRAK-M expression in RPE declined with age or oxidative stress and was further reduced in AMD. IRAK-M-deficient mice exhibited increased incidence of outer retinal degeneration at earlier ages, which was further exacerbated by oxidative stressors. The absence of IRAK-M disrupted RPE cell homeostasis, including compromised mitochondrial function, cellular senescence, and aberrant cytokine production. IRAK-M overexpression protected RPE cells against oxidative or immune stressors. Subretinal delivery of AAV-expressing IRAK-M rescued light-induced outer retinal degeneration in wild-type mice and attenuated age-related spontaneous retinal degeneration in IRAK-M-deficient mice. Our data support that replenishment of IRAK-M expression may redress dysregulated pro-inflammatory processes in AMD, thereby treating degeneration.
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Affiliation(s)
- Jian Liu
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - David A. Copland
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Alison J. Clare
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Mathias Gorski
- Department of Genetic Epidemiology, University of Regensburg, Regensburg, Germany
| | - Burt T. Richards
- Sharon Eccles Steele Center for Translational Medicine, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, United States
| | - Louis Scott
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Sofia Theodoropoulou
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Ursula Greferath
- Department of Anatomy and Physiology, University of Melbourne, Victoria, Australia
| | - Katherine Cox
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Oliver H. Bell
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Kepeng Ou
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Jenna Le Brun Powell
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Jiahui Wu
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Luis Martinez Robles
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Yingxin Li
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Lindsay B. Nicholson
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Peter J. Coffey
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Erica L. Fletcher
- Department of Anatomy and Physiology, University of Melbourne, Victoria, Australia
| | - Robyn Guymer
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Australia
| | - Monte J. Radeke
- Neuroscience Research Institute, University of California, Santa Barbara, California, United States
| | - Iris M. Heid
- Department of Genetic Epidemiology, University of Regensburg, Regensburg, Germany
| | - Gregory S. Hageman
- Sharon Eccles Steele Center for Translational Medicine, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, United States
| | - Ying Kai Chan
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts, United States
| | - Andrew D. Dick
- Academic Unit of Ophthalmology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
- Institute of Ophthalmology, University College London, London, United Kingdom
- National Institute for Health Research Biomedical Research Centre, Moorfields Eye Hospital, London, United Kingdom
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7
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Leśniak M, Lipniarska J, Majka P, Kopyt W, Lejman M, Zawitkowska J. The Role of TRL7/8 Agonists in Cancer Therapy, with Special Emphasis on Hematologic Malignancies. Vaccines (Basel) 2023; 11:vaccines11020277. [PMID: 36851155 PMCID: PMC9967151 DOI: 10.3390/vaccines11020277] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 01/31/2023] Open
Abstract
Toll-like receptors (TLR) belong to the pattern recognition receptors (PRR). TLR7 and the closely correlated TLR8 affiliate with toll-like receptors family, are located in endosomes. They recognize single-stranded ribonucleic acid (RNA) molecules and synthetic deoxyribonucleic acid (DNA)/RNA analogs-oligoribonucleotides. TLRs are primarily expressed in hematopoietic cells. There is compiling evidence implying that TLRs also direct the formation of blood cellular components and make a contribution to the pathogenesis of certain hematopoietic malignancies. The latest research shows a positive effect of therapy with TRL agonists on the course of hemato-oncological diseases. Ligands impact activation of antigen-presenting cells which results in production of cytokines, transfer of mentioned cells to the lymphoid tissue and co-stimulatory surface molecules expression required for T-cell activation. Toll-like receptor agonists have already been used in oncology especially in the treatment of dermatological neoplastic lesions. The usage of these substances in the treatment of solid tumors is being investigated. The present review discusses the direct and indirect influence that TLR7/8 agonists, such as imiquimod, imidazoquinolines and resiquimod have on neoplastic cells and their promising role as adjuvants in anticancer vaccines.
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Affiliation(s)
- Maria Leśniak
- Student Scientific Society of Department of Pediatric Hematology, Oncology and Transplantology, Medical University of Lublin, 20-093 Lublin, Poland
| | - Justyna Lipniarska
- Student Scientific Society of Department of Pediatric Hematology, Oncology and Transplantology, Medical University of Lublin, 20-093 Lublin, Poland
| | - Patrycja Majka
- Student Scientific Society of Department of Pediatric Hematology, Oncology and Transplantology, Medical University of Lublin, 20-093 Lublin, Poland
| | - Weronika Kopyt
- Student Scientific Society of Department of Pediatric Hematology, Oncology and Transplantology, Medical University of Lublin, 20-093 Lublin, Poland
| | - Monika Lejman
- Independent Laboratory of Genetic Diagnostics, Medical University of Lublin, 20-093 Lublin, Poland
| | - Joanna Zawitkowska
- Department of Pediatric Hematology, Oncology and Transplantology, Medical University of Lublin, 20-093 Lublin, Poland
- Correspondence:
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8
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Patel RS, Lui A, Hudson C, Moss L, Sparks RP, Hill SE, Shi Y, Cai J, Blair LJ, Bickford PC, Patel NA. Small molecule targeting long noncoding RNA GAS5 administered intranasally improves neuronal insulin signaling and decreases neuroinflammation in an aged mouse model. Sci Rep 2023; 13:317. [PMID: 36609440 PMCID: PMC9822944 DOI: 10.1038/s41598-022-27126-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Accepted: 12/26/2022] [Indexed: 01/09/2023] Open
Abstract
Shifts in normal aging set stage for neurodegeneration and dementia affecting 1 in 10 adults. The study demonstrates that lncRNA GAS5 is decreased in aged and Alzheimer's disease brain. The role and targets of lncRNA GAS5 in the aging brain were elucidated using a GAS5-targeting small molecule NPC86, a frontier in lncRNA-targeting therapeutic. Robust techniques such as molecular dynamics simulation of NPC86 binding to GAS5, in vitro functional assays demonstrating that GAS5 regulates insulin signaling, neuronal survival, phosphorylation of tau, and neuroinflammation via toll-like receptors support the role of GAS5 in maintaining healthy neurons. The study demonstrates the safety and efficacy of intranasal NPC86 treatment in aged mice to improve cellular functions with transcriptomic analysis in response to NPC86. In summary, the study demonstrates that GAS5 contributes to pathways associated with neurodegeneration and NPC86 has tremendous therapeutic potential to prevent the advent of neurodegenerative diseases and dementias.
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Affiliation(s)
- Rekha S. Patel
- grid.281075.90000 0001 0624 9286James A. Haley Veterans Hospital, Research Service, 13000 Bruce B. Downs Blvd., Tampa, FL 33612 USA
| | - Ashley Lui
- grid.170693.a0000 0001 2353 285XDepartment of Molecular Medicine, University of South Florida, Tampa, FL 33612 USA
| | - Charles Hudson
- grid.281075.90000 0001 0624 9286James A. Haley Veterans Hospital, Research Service, 13000 Bruce B. Downs Blvd., Tampa, FL 33612 USA
| | - Lauren Moss
- grid.170693.a0000 0001 2353 285XDepartment of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL 33612 USA
| | - Robert P. Sparks
- Present Address: UMass Chan Medical School, Worcester, MA 01655 USA
| | - Shannon E. Hill
- grid.170693.a0000 0001 2353 285XDepartment of Molecular Medicine, University of South Florida, Tampa, FL 33612 USA ,grid.170693.a0000 0001 2353 285XUSF Health Byrd Institute, University of South Florida, Tampa, FL 33612 USA
| | - Yan Shi
- grid.170693.a0000 0001 2353 285XDepartment of Chemistry, University of South Florida, Tampa, FL 33612 USA
| | - Jianfeng Cai
- grid.170693.a0000 0001 2353 285XDepartment of Chemistry, University of South Florida, Tampa, FL 33612 USA
| | - Laura J. Blair
- grid.281075.90000 0001 0624 9286James A. Haley Veterans Hospital, Research Service, 13000 Bruce B. Downs Blvd., Tampa, FL 33612 USA ,grid.170693.a0000 0001 2353 285XDepartment of Molecular Medicine, University of South Florida, Tampa, FL 33612 USA ,grid.170693.a0000 0001 2353 285XUSF Health Byrd Institute, University of South Florida, Tampa, FL 33612 USA
| | - Paula C. Bickford
- grid.281075.90000 0001 0624 9286James A. Haley Veterans Hospital, Research Service, 13000 Bruce B. Downs Blvd., Tampa, FL 33612 USA ,grid.170693.a0000 0001 2353 285XDepartment of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL 33612 USA
| | - Niketa A. Patel
- grid.281075.90000 0001 0624 9286James A. Haley Veterans Hospital, Research Service, 13000 Bruce B. Downs Blvd., Tampa, FL 33612 USA ,grid.170693.a0000 0001 2353 285XDepartment of Molecular Medicine, University of South Florida, Tampa, FL 33612 USA
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9
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Molecular subtypes of ALS are associated with differences in patient prognosis. Nat Commun 2023; 14:95. [PMID: 36609402 PMCID: PMC9822908 DOI: 10.1038/s41467-022-35494-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 12/06/2022] [Indexed: 01/09/2023] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease with poorly understood clinical heterogeneity, underscored by significant differences in patient age at onset, symptom progression, therapeutic response, disease duration, and comorbidity presentation. We perform a patient stratification analysis to better understand the variability in ALS pathology, utilizing postmortem frontal and motor cortex transcriptomes derived from 208 patients. Building on the emerging role of transposable element (TE) expression in ALS, we consider locus-specific TEs as distinct molecular features during stratification. Here, we identify three unique molecular subtypes in this ALS cohort, with significant differences in patient survival. These results suggest independent disease mechanisms drive some of the clinical heterogeneity in ALS.
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10
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Fu YY, Cen JK, Song HL, Song SY, Zhang ZJ, Lu HJ. Ginsenoside Rh2 Ameliorates Neuropathic Pain by inhibition of the miRNA21-TLR8-MAPK axis. Mol Pain 2022; 18:17448069221126078. [PMID: 36039405 PMCID: PMC9478689 DOI: 10.1177/17448069221126078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Ginsenoside Rh2 is one of the major bioactive ginsenosides in Panax
ginseng. Although Rh2 is known to enhance immune cells activity for
treatment of cancer, its anti-inflammatory and neuroprotective effects have yet
to be determined. In this study, we investigated the effects of Rh2 on spared
nerve injury (SNI)-induced neuropathic pain and elucidated the potential
mechanisms. We found that various doses of Rh2 intrathecal injection
dose-dependently attenuated SNI-induced mechanical allodynia and thermal
hyperalgesia. Rh2 also inhibited microglia and astrocyte activation in the
spinal cord of a murine SNI model. Rh2 treatment inhibited SNI-induced increase
of proinflammatory cytokines, including tumor necrosis factor-α, interleukin
(IL)-1 and IL-6. Expression of miRNA-21, an endogenous ligand of Toll like
receptor (TLR)8 was also decreased. Rh2 treatment blocked the mitogen-activated
protein kinase (MAPK) signaling pathway by inhibiting of phosphorylated
extracellular signal-regulated kinase expression. Finally, intrathecal injection
of TLR8 agonist VTX-2337 reversed the analgesic effect of Rh2. These results
indicated that Rh2 relieved SNI-induced neuropathic pain via inhibiting the
miRNA-21-TLR8-MAPK signaling pathway, thus providing a potential application of
Rh2 in pain therapy.
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Affiliation(s)
- Yuan-Yuan Fu
- Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu, China
- Department of Human Anatomy, School
of Medicine, Nantong University, Jiangsu, China
| | - Jian-Ke Cen
- Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu, China
| | - Hao-Lin Song
- Department of Human Anatomy, School
of Medicine, Nantong University, Jiangsu, China
| | - Si-Yuan Song
- Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu, China
| | - Zhi-Jun Zhang
- Department of Human Anatomy, School
of Medicine, Nantong University, Jiangsu, China
- Zhi-jun Zhang, Department of Human Anatomy,
School of Medicine, Nantong University, Jiangsu 226019, China,
| | - Huan-Jun Lu
- Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu, China
- Huan-Jun Lu, Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu 226019, China,
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11
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Seizer L, Rahimi S, Santos-Sierra S, Drexel M. Expression of toll like receptor 8 (TLR8) in specific groups of mouse hippocampal interneurons. PLoS One 2022; 17:e0267860. [PMID: 35507634 PMCID: PMC9067651 DOI: 10.1371/journal.pone.0267860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 04/16/2022] [Indexed: 11/18/2022] Open
Abstract
Toll-like receptors (TLR) are one of the main constituents of the innate immune system in mammals. They can detect conserved microbial structures (pathogen-associated molecular patterns) and host-derived ligands that are produced during cellular stress and damage (danger-associated molecular patterns) and may then initiate an intracellular signaling cascade leading to the expression of pro-inflammatory cytokines and immediate immune responses. Some TLR (TLR1, 2, 4, 5, and 6) are expressed on the cell surface while others (TLR3, 7, 8 and 9) are present on the surface of endosomes and their ligands require internalization before recognition is possible. Several TLR have also been detected in neurons where they may serve functions that are not related to immune responses. TLR2, 3, and 4 have been described in cortical neurons and, for TLR4, a seizure-promoting role in epilepsies associated with inflammation has been shown. TLR3, 7, and 8 expressed in neurons seem to influence the growth or withdrawal of neurites and robust activation of TLR8 in neurons may even induce neuronal death. The goal of the current study was to investigate the expression of TLR8 in the hippocampus of mice during postnatal development and in adulthood. We focused on three functionally distinct groups of GABAergic interneurons characterized by the expression of the molecular markers parvalbumin, somatostatin, or calretinin, and we applied double fluorescence immunohistochemistry and cell counts to quantify co-expression of TLR8 in the three groups of GABA-interneurons across hippocampal subregions. We found subregion-specific differences in the expression of TLR8 in these interneurons. During postnatal development, TLR8 was detected only in mice older than P5. While only a small fraction of hippocampal calretinin-positive interneurons expressed TLR8, most parvalbumin-positive interneurons in all hippocampal subregions co-expressed TLR8. Somatostatin-positive interneurons co-expressing TLR8 were mainly present in hippocampal sector CA3 but rare in the dentate gyrus and CA1. High expression of TLR8 in parvalbumin-interneurons may contribute to their high vulnerability in human temporal lobe epilepsy.
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Affiliation(s)
- Lennart Seizer
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
- Institute of Psychology, University of Innsbruck, Innsbruck, Austria
| | - Sadegh Rahimi
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | | | - Meinrad Drexel
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
- * E-mail:
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12
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Lane LM, McDermott MB, O'Connor P, Cronly S, O'Regan M, De Gascun CF, Morley U, Snow A, Tone S, Heffernan J, Cryan JB. Multicystic Encephalomalacia: The Neuropathology of Systemic Neonatal Parechovirus Infection. Pediatr Dev Pathol 2021; 24:460-466. [PMID: 33754905 DOI: 10.1177/10935266211001645] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The Neuropathology of Human Parechovirus (HPeV) is not widely described due to the relatively recent discovery of the virus combined with a limited number of autopsy case reports. We report the case of an infant boy born at 38 weeks who, six days after birth, presented with fever and severe neurological dysfunction. Human Parechovirus Type 3 (HPeV3) RNA was detected in his cerebrospinal fluid (CSF) and blood. He died five days after his initial presentation. Neuropathologic examination demonstrated multicystic encephalomalacia (ME). This case report confirms that white matter pathology is dominant in HPeV3 infection. A unique feature, of HPeV encephalomalacia is absence of CSF pleocytosis and minimal inflammation in the meninges. The findings permit comment on the pathogenesis of brain injury by this virus.
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Affiliation(s)
- Louise Marie Lane
- Department of Pathology, Children's Health Ireland, Temple Street, Dublin, Ireland
| | - Michael B McDermott
- Department of Pathology, Children's Health Ireland, Our Lady's Children's Hospital Crumlin, Dublin, Ireland
| | - Pamela O'Connor
- Department of Neonatology, Children's Health Ireland, Our Lady's Children's Hospital Crumlin, Dublin, Ireland
| | - Suzanne Cronly
- Department of Anesthesiology, Children's Health Ireland, Our Lady's Children's Hospital Crumlin, Dublin, Ireland
| | - Mary O'Regan
- Department of Paediatric Neurology, Children's Health Ireland, Our Lady's Children's Hospital Crumlin, Dublin, Ireland
| | - Cillian F De Gascun
- The National Virus Reference Laboratory, University College Dublin, Dublin, Ireland
| | - Ursula Morley
- The National Virus Reference Laboratory, University College Dublin, Dublin, Ireland
| | - Aisling Snow
- Department of Radiology, Children's Health Ireland, Our Lady's Children's Hospital Crumlin, Dublin, Ireland
| | - Sara Tone
- Department of Pathology, Children's Health Ireland, Temple Street, Dublin, Ireland
| | | | - Jane B Cryan
- Department of Pathology, Children's Health Ireland, Temple Street, Dublin, Ireland
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13
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Hossack MR, Reid MW, Aden JK, Gibbons T, Noe JC, Willis AM. Adverse Childhood Experience, Genes, and PTSD Risk in Soldiers: A Methylation Study. Mil Med 2021; 185:377-384. [PMID: 32976583 DOI: 10.1093/milmed/usz292] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 07/27/2019] [Accepted: 07/30/2019] [Indexed: 11/12/2022] Open
Abstract
INTRODUCTION Epigenetics can serve as a marker of susceptibility to many known psychiatric diseases. DNA methylation patterns of multiple genes have been studied in both civilian populations and military personnel with post-traumatic stress disorder (PTSD). Many of these genes serve various functions that span the hypothalamic-pituitary-adrenal axis, immune system, and central nervous system (CNS) growth factors and neurotransmission. It is thought that the methylation levels of such genes may be able to identify individuals who are at higher risk of developing PTSD. Our study seeks to establish whether previously reported PTSD genes possess a particular methylation pattern that is predictive of PTSD in active duty military members with combat exposure. MATERIALS AND METHODS This is an institutional review board (IRB)-approved, cross-sectional, case control, gene-environment interaction study. About 170 active military members with and without PTSD were recruited. Patients with a history of structural brain damage, traumatic brain injury (TBI) resulting in loss of consciousness, predeployment diagnosis of PTSD or anxiety disorder, and predeployment prescription of an antidepressant or psychoactive medication were excluded. Validated measures of childhood trauma and adversity (adverse childhood experience [ACE] score), PTSD symptoms (PTSD check-list military version [PCL-M]), and combat exposure scales (CES) were measured via validated questionnaires for all subjects. After extracting DNA from peripheral blood provided by the 170 subjects, we determined methylation percentages, via pyrosequencing assays, for nine target areas within the following seven genes: BDNF, NR3C1, MAN2C1, TLR8, SLC6A4, IL-18, and SKA2. These genes are commonly reported in the literature as being highly correlated with PTSD and early-life traumatic experiences.Methylation levels were measured as a percentage at specific sites within the previously mentioned genes. Data were examined with SPSS v 22.0 Statistics and JMP v13.1 software using a general linear model for methylation × trauma (CES scores) split by diagnosis of PTSD or not, methylation versus childhood trauma (ACE scores), and methylation versus PTSD severity (PCL-M score). Two-way ANOVA was performed to control for antidepressant use. A two-tailed Student t-test was performed for PTSD analyses and was correlated with PTSD diagnosis, demographic information as well as ACE score, PCL-M score, and CES scores. RESULTS Differentially methylated sites that were highly associated with PTSD diagnosis were found in three of seven candidate genes: BDNF, NR3C1, and MAN2C1. When compared to controls, patients with PTSD diagnosis had significantly lower levels of methylation, even after controlling for antidepressant use. PCL-M, ACE, and CES scores were significantly associated with PTSD diagnosis. CONCLUSION Our study suggests that methylation of key genes involved in synaptic plasticity and the hypothalamic-pituitary-adrenal axis is associated with lower levels of methylation in military PTSD subjects exposed to combat when compared to their non-PTSD counterparts. Strengths of this study include controlling for antidepressant use and excluding TBI patients. Similar studies in an active duty population of this size are scarce. What is not clear is whether methylation changes are driving PTSD symptomology or whether they are merely a marker of disease. Future areas of research include prospective studies that measure methylation pre- and postcombat exposure in the same individual.
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Affiliation(s)
- Michael R Hossack
- Department of Neurology, San Antonio Military Medical Center, 3551 Roger Brooke Drive, Fort Sam Houston, TX 78234
| | - Matthew W Reid
- Defense and Veterans Brain Injury Center, San Antonio Military Medical Center, 3551 Roger Brooke Drive, Fort Sam Houston, TX 78234
| | - James K Aden
- Graduate Medical Education, Brooke Army Medical Center, 3698 Chambers Pass, Fort Sam Houston, TX 78234
| | - Thomas Gibbons
- Laboratory Services Branch, Clinical Investigations & Research Support, 1255 Wilford Hall Loop, BLDG 4430, Lackland AFB, TX 78236
| | - Jody C Noe
- 59 MDW/SGVUL, Clinical Research Division, 2200 Bergquist Dr, BLDG 4430, Lackland AFB, TX 78236
| | - Adam M Willis
- Department of Neurology, San Antonio Military Medical Center, 3551 Roger Brooke Drive, Fort Sam Houston, TX 78234.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern, 5303 Harry Hinds Blvd, Dallas, TX 75390.,Department of Mechanical Engineering, Michigan State University, 428 S. Shaw Lane, Room 2555, Engineering Building, East Lansing, MI 48824-1226
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14
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Sharma D, Farrar JD. Adrenergic regulation of immune cell function and inflammation. Semin Immunopathol 2020; 42:709-717. [PMID: 33219396 PMCID: PMC7678770 DOI: 10.1007/s00281-020-00829-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 11/14/2020] [Indexed: 02/06/2023]
Abstract
The sympathetic nervous system integrates the functions of multiple organ systems by regulating their autonomic physiological activities. The immune system is regulated both locally and systemically by the neurotransmitters epinephrine and norepinephrine secreted by the adrenal gland and local sympathetic neurons. Immune cells respond by activation of adrenergic receptors, primarily the β2-adrenergic receptor, which signal through heterotrimeric G-proteins. Depending upon the cell type, adrenergic signaling regulates a variety of functions in immune cells ranging from cellular migration to cytokine secretion. Furthermore, due to the diurnal oscillation of systemic norepinephrine levels, various immune functions follow a circadian rhythmic pattern. This review will highlight recent advances in our understanding of how the sympathetic nervous system regulates both innate and adaptive immune functions and how this regulation is linked to circadian rhythms.
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Affiliation(s)
- Drashya Sharma
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX, USA
| | - J David Farrar
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX, USA.
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15
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Toll-like receptors in Alzheimer's disease. J Neuroimmunol 2020; 348:577362. [DOI: 10.1016/j.jneuroim.2020.577362] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/04/2020] [Accepted: 08/15/2020] [Indexed: 02/07/2023]
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16
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Woo YJ, Roussos P, Haroutunian V, Katsel P, Gandy S, Schadt EE, Zhu J. Comparison of brain connectomes by MRI and genomics and its implication in Alzheimer's disease. BMC Med 2020; 18:23. [PMID: 32024511 PMCID: PMC7003435 DOI: 10.1186/s12916-019-1488-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 12/24/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND The human brain is complex and interconnected structurally. Brain connectome change is associated with Alzheimer's disease (AD) and other neurodegenerative diseases. Genetics and genomics studies have identified molecular changes in AD; however, the results are often limited to isolated brain regions and are difficult to interpret its findings in respect to brain connectome. The mechanisms of how one brain region impacts the molecular pathways in other regions have not been systematically studied. And how the brain regions susceptible to AD pathology interact with each other at the transcriptome level and how these interactions relate to brain connectome change are unclear. METHODS Here, we compared structural brain connectomes defined by probabilistic tracts using diffusion magnetic resonance imaging data in Alzheimer's Disease Neuroimaging Initiative database and a brain transcriptome dataset covering 17 brain regions. RESULTS We observed that the changes in diffusion measures associated with AD diagnosis status and the associations were replicated in an independent cohort. The result suggests that disease associated white matter changes are focal. Analysis of the brain connectome by genomic data, tissue-tissue transcriptional synchronization between 17 brain regions, indicates that the regions connected by AD-associated tracts were likely connected at the transcriptome level with high number of tissue-to-tissue correlated (TTC) gene pairs (P = 0.03). And genes involved in TTC gene pairs between white matter tract connected brain regions were enriched in signaling pathways (P = 6.08 × 10-9). Further pathway interaction analysis identified ionotropic glutamate receptor pathway and Toll receptor signaling pathways to be important for tissue-tissue synchronization at the transcriptome level. Transcript profile entailing Toll receptor signaling in the blood was significantly associated with diffusion properties of white matter tracts, notable association between fractional anisotropy and bilateral cingulum angular bundles (Ppermutation = 1.0 × 10-2 and 4.9 × 10-4 for left and right respectively). CONCLUSIONS In summary, our study suggests that brain connectomes defined by MRI and transcriptome data overlap with each other.
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Affiliation(s)
- Young Jae Woo
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Panos Roussos
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Vahram Haroutunian
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Pavel Katsel
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Samuel Gandy
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Eric E Schadt
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Sema4, Stamford, CT, 06902, USA
| | - Jun Zhu
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- Sema4, Stamford, CT, 06902, USA.
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17
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Shin SD, Shin A, Mayagoitia K, Siebold L, Rubini M, Wilson CG, Bellinger DL, Soriano S. Loss of amyloid precursor protein exacerbates early inflammation in Niemann-Pick disease type C. J Neuroinflammation 2019; 16:269. [PMID: 31847862 PMCID: PMC6918596 DOI: 10.1186/s12974-019-1663-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 11/26/2019] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Niemann-Pick disease type C (NPC) is a progressive neurodegenerative condition that results in early fatality. NPC is inherited in an autosomal recessive pattern from mutations in NPC1 or NPC2 genes. The etiology of NPC is poorly defined. In that regard, neuroinflammation occurs early in the disease and we have recently unveiled an atypical pattern of interferon signaling in pre-symptomatic Npc1-/- mice, with microglial activation, anti-viral response, activation of antigen-presenting cells, and activation and chemotaxis of T lymphocytes as the key affected pathologic pathways. Furthermore, IP-10/CXCL10, a potent IFN-γ-responsive cytokine, was identified as the potential mediator of these early inflammatory abnormalities. Here, we asked whether this aberrant signaling may be exacerbated by the loss of amyloid precursor protein (APP) function, a loss known to shorten lifespan and accelerate neurodegeneration in Npc1-/- mice. METHODS We carried out genome-wide comparative transcriptome analyses of pre-symptomatic Npc1+/+/App+/+, Npc1-/-/App+/+, Npc1+/+/App-/-, and Npc1-/-/App-/- mouse cerebella to identify biological pathways in the NPC brain further affected by the loss of APP. Gene Set Enrichment Analysis and Ingenuity Pathway Analysis were utilized for molecular mapping and functional upstream pathway analyses of highly differentially expressed genes. We simultaneously measured the expression of 32 inflammatory cytokines and chemokines in the cerebella from these mice, including those identified in our genome-wide analyses. Finally, we used immunohistochemistry to measure T cell infiltration in the cerebellum. RESULTS Expression of IFN-γ- and IFN-α-responsive genes in pre-symptomatic Npc1-/-/App-/- cerebella is upregulated compared with Npc1-/-/App+/+ mice, compounding the dysregulation of microglial activation, anti-viral response, activation of antigen-presenting cells, and T-lymphocyte activation and chemotaxis pathways present in the NPC brain. Multiplex protein analysis further showed elevated expression of IP-10/CXCL10, a potent downstream effector of IFN-γ, as well as RANTES/CCL5, eotaxin/CCL11 and IL-10, prior to symptomatic onset in Npc1-/-/App-/- cerebella, compared with Npc1-/-/App+/+mice. In the terminal disease stage, loss of APP caused pleiotropic differential expression of the vast majority of cytokines evaluated. Finally, we present evidence of T cell infiltration in Npc1-/-/App-/- cerebella. CONCLUSIONS Loss of APP exacerbates the pathogenic neuroinflammation that occurs prior to symptomatic onset in the NPC brain. These findings shed new light on the function of APP as a cytoprotective modulator in the CNS, offering potential evidence-based therapies against NPC.
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Affiliation(s)
- Samuel D Shin
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, 24785 Stewart St, Loma Linda, California, USA
| | - Alexandra Shin
- Department of Biological Sciences, California Baptist University, Riverside, California, USA
| | - Karina Mayagoitia
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, 24785 Stewart St, Loma Linda, California, USA
| | - Lorraine Siebold
- Lawrence D. Longo Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, California, USA
| | - Marsilio Rubini
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, 24785 Stewart St, Loma Linda, California, USA
| | - Christopher G Wilson
- Lawrence D. Longo Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, California, USA
| | - Denise L Bellinger
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, 24785 Stewart St, Loma Linda, California, USA
| | - Salvador Soriano
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, 24785 Stewart St, Loma Linda, California, USA.
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18
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Aurelian L, Balan I. GABA AR α2-activated neuroimmune signal controls binge drinking and impulsivity through regulation of the CCL2/CX3CL1 balance. Psychopharmacology (Berl) 2019; 236:3023-3043. [PMID: 31030249 DOI: 10.1007/s00213-019-05220-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 03/04/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND PURPOSE Toll-like receptors (TLRs) are a family of innate immune system receptors that respond to pathogen-derived and tissue damage-related ligands and are increasingly recognized for their impact on homeostasis and its dysregulation in the nervous system. TLR signaling participates in brain injury and addiction, but its role in the alcohol-seeking behavior, which initiates alcohol drinking, is still poorly understood. In this review, we discuss our findings designed to elucidate the potential contribution of the activated TLR4 signal located in neurons, on impulsivity and the predisposition to initiate alcohol drinking (binge drinking). RESULTS Our findings indicate that the TLR4 signal is innately activated in neurons from alcohol-preferring subjects, identifying a genetic contribution to the regulation of impulsivity and the alcohol-seeking propensity. Signal activation is through the non-canonical, previously unknown, binding of TLR4 to the α2 subunit of the γ-aminobutyric 2 acid A receptor (GABAAR α2). Activation is sustained by the stress hormone corticotrophin-releasing factor (CRF) and additional still poorly recognized ligand/scaffold proteins. Focus is on the effect of TLR4 signal activation on the balance between pro- and anti-inflammatory chemokines [chemokine (C-C motif) ligand 2 (CCL2)/chemokine (C-X3-C motif) ligand 1 (CX3CL1)] and its effect on binge drinking. CONCLUSION The results are discussed within the context of current findings on the distinct activation and functions of TLR signals located in neurons, as opposed to immune cells. They indicate that the balance between pro- and anti-inflammatory TLR4 signaling plays a major role in binge drinking. These findings have major impact on future basic and translational research, including the development of potential therapeutic and preventative strategies.
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Affiliation(s)
- Laure Aurelian
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA. .,Stanford University School of Medicine OFDD, Stanford, CA, 94305, USA.
| | - Irina Balan
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.,Department of Psychiatry and Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
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19
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Yeo IJ, Park MH, Son DJ, Kim JY, Nam KT, Hyun BK, Kim SY, Jung MH, Song MJ, Chun HO, Lee TH, Han SB, Hong JT. PRDX6 Inhibits Neurogenesis through Downregulation of WDFY1-Mediated TLR4 Signal. Mol Neurobiol 2019; 56:3132-3144. [PMID: 30097850 PMCID: PMC6476867 DOI: 10.1007/s12035-018-1287-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Accepted: 07/30/2018] [Indexed: 12/22/2022]
Abstract
Impaired neurogenesis has been associated with several brain disorders, such as Alzheimer's disease (AD) and Parkinson's disease (PD). The role of peroxiredoxin 6 (PRDX6) in neurodegenerative diseases is very controversial. To demonstrate the role of PRDX6 in neurogenesis, we compared the neurogenesis ability of PRDX6-overexpressing transgenic (Tg) mice and wild-type mice and studied the involved molecular mechanisms. We showed that the neurogenesis of neural stem cells (NSCs) and the expression of the marker protein were lower in PRDX6 Tg-mice than in wild-type mice. To determine the factors involved in PRDX6-related neural stem cell impairment, we performed a microarray experiment. We showed that the expression of WDFY1 was dramatically decreased in PRDX6-Tg mice. Moreover, WDFY1 siRNA decreases the differentiation ability of primary neural stem cells. Interestingly, WDFY1 reportedly recruits the signaling adaptor TIR-domain-containing adapter-inducing interferon-β (TRIF) to toll-like receptors (TLRs); thus, we showed the relationship among TLRs, PRDX6, and WDFY1. We showed that TLR4 was dramatically reduced in PRDX6 Tg mice, and reduced TLR4 expression and neurogenesis was reversed by the introduction of WDFY1 plasmid in the neural stem cells from PRDX6 Tg mice. This study indicated that PRDX6 inhibits the neurogenesis of neural precursor cells through TLR4-dependent downregulation of WDFY1 and suggested that the inhibitory effect of PRDX6 on neurogenesis play a role in the development of neurodegenerative diseases in the PRDX6 overexpressing transgenic mice.
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Affiliation(s)
- In Jun Yeo
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Mi Hee Park
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Dong Ju Son
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Ji Young Kim
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Kyoung Tak Nam
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Byung Kook Hyun
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - So Young Kim
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Myung Hee Jung
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Min Ji Song
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Hyung Ok Chun
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Tae Hyung Lee
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Sang-Bae Han
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea
| | - Jin Tae Hong
- College of Pharmacy and Medical Research Center, Chungbuk National University, 194-31, Osongsaengmyeong 1-ro, Heungdeok-gu, Cheongju, Chungbuk, 361-951, Republic of Korea.
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20
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Role of Toll-Like Receptors in Actuating Stem/Progenitor Cell Repair Mechanisms: Different Functions in Different Cells. Stem Cells Int 2019; 2019:6795845. [PMID: 31089331 PMCID: PMC6476106 DOI: 10.1155/2019/6795845] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 12/19/2018] [Indexed: 02/07/2023] Open
Abstract
Toll-like receptors (TLRs) represent one of the bridges that regulate the cross-talk between the innate and adaptive immune systems. TLRs interact with molecules shared and preserved by the pathogens of origin but also with endogenous molecules (damage/danger-associated molecular patterns (DAMPs)) that derive from injured tissues. This is probably why TLRs have been found to be expressed on several kinds of stem/progenitor cells (SCs). In these cells, the role of TLRs in the regulation of the basal motility, proliferation, differentiation processes, self-renewal, and immunomodulation has been demonstrated. In this review, we analyze the many different functions that the TLRs assume in SCs, pointing out that they can have different effects, depending on the background and on the kind of ligands that they recognize. Moreover, we discuss the TLR involvement in the response of SC to specific tissue damage and in the reparative processes, as well as how the identification of molecules mediating the differential function of TLR signaling could be decisive for the development of new therapeutic strategies. Considering the available studies on TLRs in SCs, here we address the importance of TLRs in sensing an injury by stem/progenitor cells and in determining their behavior and reparative activity, which is dependent on the conditions. Therefore, it could be conceivable that SCs employed in therapy could be potentially exposed to TLR ligands, which might modulate their therapeutic potential in vivo. In this context, to modulate SC proliferation, survival, migration, and differentiation in the pathological environment, we need to better understand the mechanisms of action of TLRs on SCs and learn how to control these receptors and their downstream pathways in a precise way. In this manner, in the future, cell therapy could be improved and made safer.
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21
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Morrison FG, Miller MW, Logue MW, Assef M, Wolf EJ. DNA methylation correlates of PTSD: Recent findings and technical challenges. Prog Neuropsychopharmacol Biol Psychiatry 2019; 90:223-234. [PMID: 30503303 PMCID: PMC6314898 DOI: 10.1016/j.pnpbp.2018.11.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 11/14/2018] [Accepted: 11/16/2018] [Indexed: 12/22/2022]
Abstract
There is increasing evidence that epigenetic factors play a critical role in posttraumatic stress disorder (PTSD), by mediating the impact of environmental exposures to trauma on the regulation of gene expression. DNA methylation is one epigenetic process that has been highly studied in PTSD. This review will begin by providing an overview of DNA methylation (DNAm) methods, and will then highlight two major biological systems that have been identified in the epigenetic regulation in PTSD: (a) the immune system and (b) the stress response system. In addition to candidate gene approaches, we will review novel strategies to study epigenome-wide PTSD-related effects, including epigenome-wide algorithms that distill information from many loci into a single summary score (e.g., measures of "epigenetic age" which have been associated with PTSD). This review will also cover recent epigenome wide association studies (EWAS) of PTSD, and biological pathway models used to identify gene sets enriched in PTSD. Finally, we address technical and methodological advances and challenges to the field, and highlight exciting directions for future research.
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Affiliation(s)
- Filomene G Morrison
- National Center for PTSD, VA Boston Healthcare System, USA; Department of Psychiatry, Boston University School of Medicine, USA.
| | - Mark W Miller
- National Center for PTSD, VA Boston Healthcare System, USA; Department of Psychiatry, Boston University School of Medicine, USA
| | - Mark W Logue
- National Center for PTSD, VA Boston Healthcare System, USA; Department of Psychiatry, Boston University School of Medicine, USA; Biomedical Genetics, Boston University School of Medicine, USA; Department of Biostatistics, Boston University School of Public Health, USA
| | - Michele Assef
- Boston University, College of Health & Rehabilitation Sciences: Sargent College, USA
| | - Erika J Wolf
- National Center for PTSD, VA Boston Healthcare System, USA; Department of Psychiatry, Boston University School of Medicine, USA
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22
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Noailles A, Kutsyr O, Maneu V, Ortuño-Lizarán I, Campello L, de Juan E, Gómez-Vicente V, Cuenca N, Lax P. The Absence of Toll-Like Receptor 4 Mildly Affects the Structure and Function in the Adult Mouse Retina. Front Cell Neurosci 2019; 13:59. [PMID: 30873007 PMCID: PMC6401850 DOI: 10.3389/fncel.2019.00059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 02/05/2019] [Indexed: 12/26/2022] Open
Abstract
The innate immune Toll-like receptor (TLR) family plays essential roles in cell proliferation, survival and function of the central nervous system. However, the way in which TLRs contribute to the development and maintenance of proper retinal structure and function remains uncertain. In this work, we assess the effect of genetic TLR4 deletion on the morphology and function of the retina in mice. Visual acuity and retinal responsiveness were evaluated in TLR4 knockout and wild type C57BL/6J control mice by means of an optomotor test and electroretinography, respectively, from P20 to P360. Retinal structure was also analyzed in both strains using confocal and electron microscopy. ERG data showed impaired retinal responsiveness in TLR4 KO mice, in comparison to wild type animals. The amplitudes of the scotopic a-waves were less pronounced in TLR4-deficient mice than in wild-type animals from P30 to P360, and TLR4 KO mice presented scotopic b-wave amplitudes smaller than those of age-matched control mice at all ages studied (P20 to P360). Visual acuity was also relatively poorer in TLR4 KO as compared to C57BL/6J mice from P20 to P360, with significant differences at P30 and P60. Immunohistochemical analysis of retinal vertical sections showed no differences between TLR4 KO and C57BL/6J mice, in terms of either photoreceptor number or photoreceptor structure. Horizontal cells also demonstrated no morphological differences between TLR4 KO and wild-type mice. However, TLR4 KO mice exhibited a lower density of bipolar cells (15% less at P30) and thus fewer bipolar cell dendrites than the wild type control mouse, even though both confocal and electron microscopy images showed no morphologic abnormalities in the synaptic contacts between the photoreceptors and second order neurons. Microglial cell density was significantly lower (26% less at P30) in TLR4 KO mice as compared to wild-type control mice. These results suggest that TLR4 deletion causes functional alterations in terms of visual response and acuity, probably through the loss of bipolar cells and microglia, but this receptor is not essential for the processing of visual information in the retina.
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Affiliation(s)
- Agustina Noailles
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Oksana Kutsyr
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Victoria Maneu
- Department of Optics, Pharmacology and Anatomy, University of Alicante, Alicante, Spain
| | - Isabel Ortuño-Lizarán
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Laura Campello
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Emilio de Juan
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Violeta Gómez-Vicente
- Department of Optics, Pharmacology and Anatomy, University of Alicante, Alicante, Spain
| | - Nicolás Cuenca
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain.,Institute Ramón Margalef, University of Alicante, Alicante, Spain
| | - Pedro Lax
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
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23
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Zhang ZJ, Guo JS, Li SS, Wu XB, Cao DL, Jiang BC, Jing PB, Bai XQ, Li CH, Wu ZH, Lu Y, Gao YJ. TLR8 and its endogenous ligand miR-21 contribute to neuropathic pain in murine DRG. J Exp Med 2018; 215:3019-3037. [PMID: 30455267 PMCID: PMC6279408 DOI: 10.1084/jem.20180800] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 09/10/2018] [Accepted: 10/17/2018] [Indexed: 01/20/2023] Open
Abstract
TLRs are known to be essential for innate and adaptive immunity. Zhang et al. show the involvement of TLR8 and its endogenous ligand miR-21 in neuropathic pain via inducing ERK-dependent proinflammatory mediators’ production and neuronal hyperexcitability in the DRG. Toll-like receptors (TLRs) are nucleic acid–sensing receptors and have been implicated in mediating pain and itch. Here we report that Tlr8−/− mice show normal itch behaviors, but have defects in neuropathic pain induced by spinal nerve ligation (SNL) in mice. SNL increased TLR8 expression in small-diameter IB4+ DRG neurons. Inhibition of TLR8 in the DRG attenuated SNL-induced pain hypersensitivity. Conversely, intrathecal or intradermal injection of TLR8 agonist, VTX-2337, induced TLR8-dependent pain hypersensitivity. Mechanistically, TLR8, localizing in the endosomes and lysosomes, mediated ERK activation, inflammatory mediators’ production, and neuronal hyperexcitability after SNL. Notably, miR-21 was increased in DRG neurons after SNL. Intrathecal injection of miR-21 showed the similar effects as VTX-2337 and inhibition of miR-21 in the DRG attenuated neuropathic pain. The present study reveals a previously unknown role of TLR8 in the maintenance of neuropathic pain, suggesting that miR-21–TLR8 signaling may be potential new targets for drug development against this type of chronic pain.
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Affiliation(s)
- Zhi-Jun Zhang
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China.,Department of Human Anatomy, School of Medicine, Nantong University, Jiangsu, China
| | - Jian-Shuang Guo
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China
| | - Si-Si Li
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China
| | - Xiao-Bo Wu
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China
| | - De-Li Cao
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China
| | - Bao-Chun Jiang
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China
| | - Peng-Bo Jing
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China
| | - Xue-Qiang Bai
- Department of Human Anatomy, School of Medicine, Nantong University, Jiangsu, China
| | - Chun-Hua Li
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China
| | - Zi-Han Wu
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China.,Department of Human Anatomy, School of Medicine, Nantong University, Jiangsu, China
| | - Ying Lu
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China.,Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Jiangsu, China
| | - Yong-Jing Gao
- Pain Research Laboratory, Institute of Nautical Medicine, Nantong University, Jiangsu, China .,Co-innovation Center of Neuroregeneration, Nantong University, Jiangsu, China
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24
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Ağaç D, Estrada LD, Maples R, Hooper LV, Farrar JD. The β2-adrenergic receptor controls inflammation by driving rapid IL-10 secretion. Brain Behav Immun 2018; 74:176-185. [PMID: 30195028 PMCID: PMC6289674 DOI: 10.1016/j.bbi.2018.09.004] [Citation(s) in RCA: 126] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 08/01/2018] [Accepted: 09/04/2018] [Indexed: 12/24/2022] Open
Abstract
The mammalian nervous system communicates important information about the environment to the immune system, but the underlying mechanisms are largely unknown. Secondary lymphoid organs are highly innervated by sympathetic neurons that secrete norepinephrine (NE) as the primary neurotransmitter. Immune cells express adrenergic receptors, enabling the sympathetic nervous system to directly control immune function. NE is a potent immunosuppressive factor and markedly inhibits TNF-α secretion from innate cells in response to lipopolysaccharide (LPS). In this study, we demonstrate that NE blocks the secretion of a variety of proinflammatory cytokines by rapidly inducing IL-10 secretion from innate cells in response to multiple Toll-like receptor (TLR) signals. NE mediated these effects exclusively through the β2-adrenergic receptor (ADRB2). Consequently, Adrb2-/- animals were more susceptible to L. monocytogenes infection and to intestinal inflammation in a dextran sodium sulfate (DSS) model of colitis. Further, Adrb2-/- animals rapidly succumbed to endotoxemia in response to a sub-lethal LPS challenge and exhibited elevated serum levels of TNF-α and reduced IL-10. LPS-mediated lethality in WT animals was rescued by administering a β 2-specific agonist and in Adrb2-/- animals by exogenous IL-10. These findings reveal a critical role for ADRB2 signaling in controlling inflammation through the rapid induction of IL-10. Our findings provide a fundamental insight into how the sympathetic nervous system controls a critical facet of immune function through ADRB2 signaling.
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Affiliation(s)
- Didem Ağaç
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX
| | | | - Robert Maples
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX
| | - Lora V. Hooper
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX,Howard Hughes Medical Institute
| | - J. David Farrar
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX
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25
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Chistyakov DV, Astakhova AA, Sergeeva MG. Resolution of inflammation and mood disorders. Exp Mol Pathol 2018; 105:190-201. [PMID: 30098318 DOI: 10.1016/j.yexmp.2018.08.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 07/21/2018] [Accepted: 08/07/2018] [Indexed: 02/08/2023]
Abstract
Relationship between mood disorders and inflammation is now well-documented, although molecular mechanisms are not understood. Previously mostly pro-inflammatory cytokines of immune system (IL-6, TNF, etc.) were taken into account. However, recent understanding of resolution of inflammation as an active process drew attention to mediators of resolution, which include both proteins and ω-3 and ω-6 polyunsaturated fatty acids derivatives (resolvins, cyclopentenone prostaglandins, etc.). This review takes into account new data on resolution of inflammation and action of mediators of resolution in models of depression. New facts and ideas about mechanisms of chronic inflammation onset are considered in relation to mood disorders. Basic control mechanisms of inflammation at the cellular level and the role of resolution substances in regulation of depression and other mood disorders are discussed. Signaling systems of innate immunity located in non-immune cells and their ability to generate substances that affect an onset of depression are reviewed. A novel hypothesis of depression as a type of abnormal resolution is proposed.
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Affiliation(s)
- Dmiry V Chistyakov
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia; Pirogov Russian National Research Medical University, Moscow, Russia
| | - Alina A Astakhova
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia
| | - Marina G Sergeeva
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia.
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26
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Alpha/Beta Interferon (IFN-α/β) Signaling in Astrocytes Mediates Protection against Viral Encephalomyelitis and Regulates IFN-γ-Dependent Responses. J Virol 2018; 92:JVI.01901-17. [PMID: 29491163 PMCID: PMC5923078 DOI: 10.1128/jvi.01901-17] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 02/22/2018] [Indexed: 12/25/2022] Open
Abstract
The contribution of distinct central nervous system (CNS) resident cells to protective alpha/beta interferon (IFN-α/β) function following viral infections is poorly understood. Based on numerous immune regulatory functions of astrocytes, we evaluated the contribution of astrocyte IFN-α/β signaling toward protection against the nonlethal glia- and neuronotropic mouse hepatitis virus (MHV) strain A59. Analysis of gene expression associated with IFN-α/β function, e.g., pattern recognition receptors (PRRs) and interferon-stimulated genes (ISGs), revealed lower basal mRNA levels in brain-derived astrocytes than in microglia. Although astrocytes poorly induced Ifnβ mRNA following infection, they upregulated various mRNAs in the IFN-α/β pathway to a higher extent than microglia, supporting effective IFN-α/β responsiveness. Ablation of the IFN-α/β receptor (IFNAR) in astrocytes using mGFAPcre IFNARfl/fl mice resulted in severe encephalomyelitis and mortality, coincident with uncontrolled virus replication. Further, virus spread was not restricted to astrocytes but also affected microglia and neurons, despite increased and sustained Ifnα/β and ISG mRNA levels within the CNS. IFN-γ, a crucial mediator for MHV control, was not impaired in infected mGFAPcre IFNARfl/fl mice despite reduced T cell CNS infiltration. Unexpectedly however, poor induction of IFN-γ-dependent major histocompatibility complex (MHC) class II expression on microglia supported that defective IFN-γ signaling contributes to uncontrolled virus replication. A link between sustained elevated IFN-α/β and impaired responsiveness to IFN-γ supports the novel concept that temporally limited early IFN-α/β responses are critical for effective antiviral IFN-γ function. Overall, our results imply that IFN-α/β signaling in astrocytes is not only critical in limiting early CNS viral spread but also promotes protective antiviral IFN-γ function.IMPORTANCE An antiviral state established by IFN-α/β contains initial viral spread as adaptive immunity develops. While it is apparent that the CNS lacks professional IFN-α/β producers and that resident cells have distinct abilities to elicit innate IFN-α/β responses, protective interactions between inducer and responder cells require further investigation. Infection with a glia- and neuronotropic coronavirus demonstrates that astrocytes mount a delayed but more robust response to infection than microglia, despite their lower basal mRNA levels of IFN-α/β-inducing components. Lethal, uncontrolled viral dissemination following ablation of astrocyte IFN-α/β signaling revealed the importance of IFN-α/β responses in a single cell type for protection. Sustained global IFN-α/β expression associated with uncontrolled virus did not suffice to protect neurons and further impaired responsiveness to protective IFN-γ. The results support astrocytes as critical contributors to innate immunity and the concept that limited IFN-α/β responses are critical for effective subsequent antiviral IFN-γ function.
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27
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Anthoney N, Foldi I, Hidalgo A. Toll and Toll-like receptor signalling in development. Development 2018; 145:145/9/dev156018. [DOI: 10.1242/dev.156018] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
ABSTRACT
The membrane receptor Toll and the related Toll-like receptors (TLRs) are best known for their universal function in innate immunity. However, Toll/TLRs were initially discovered in a developmental context, and recent studies have revealed that Toll/TLRs carry out previously unanticipated functions in development, regulating cell fate, cell number, neural circuit connectivity and synaptogenesis. Furthermore, knowledge of their molecular mechanisms of action is expanding and has highlighted that Toll/TLRs function beyond the canonical NF-κB pathway to regulate cell-to-cell communication and signalling at the synapse. Here, we provide an overview of Toll/TLR signalling and discuss how this signalling pathway regulates various aspects of development across species.
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Affiliation(s)
- Niki Anthoney
- NeuroDevelopment Group, School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Istvan Foldi
- NeuroDevelopment Group, School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Alicia Hidalgo
- NeuroDevelopment Group, School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK
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28
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Toonen LJA, Casaca-Carreira J, Pellisé-Tintoré M, Mei H, Temel Y, Jahanshahi A, van Roon-Mom WMC. Intracerebroventricular Administration of a 2'-O-Methyl Phosphorothioate Antisense Oligonucleotide Results in Activation of the Innate Immune System in Mouse Brain. Nucleic Acid Ther 2018; 28:63-73. [PMID: 29565739 PMCID: PMC5899290 DOI: 10.1089/nat.2017.0705] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Antisense oligonucleotides (AONs) are versatile molecules that can be used to modulate gene expression by binding to RNA. The therapeutic potential of AONs appears particularly high in the central nervous system, due to excellent distribution and uptake in brain cells, as well as good tolerability in clinical trials thus far. Nonetheless, immune stimulation in response to AON treatment in the brain remains a concern. For this reason we performed RNA sequencing analysis of brain tissue from mice treated intracerebroventricularly with phosphorothioate, 2′-O-methyl modified AONs. A significant upregulation of immune system associated genes was observed in brains of AON treated mice, with the striatum showing largest transcriptional changes. Strongest upregulation was seen for the antiviral enzyme 2′-5′-oligoadenylate synthase-like protein 2 (Oasl2) and Bone marrow stromal antigen 2 (Bst2). Histological analysis confirmed activation of microglia and astrocytes in striatum. The upregulation of immune system associated genes was detectable for at least 2 months after the last AON administration, consistent with a continuous immune response to the AON.
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Affiliation(s)
- Lodewijk J A Toonen
- 1 Department of Human Genetics, Leiden University Medical Center , Leiden, the Netherlands
| | - João Casaca-Carreira
- 2 Department of Neurosurgery, Maastricht University Medical Center , Maastricht, the Netherlands .,3 European Graduate School of Neuroscience (EURON) , Maastricht, the Netherlands .,4 Department of Physiotherapy, Portuguese Red Cross Health School , Lisbon, Portugal .,5 Department of Physiotherapy, School of Health Care , Setubal Polytechnic Institute, Setubal, Portugal
| | - Maria Pellisé-Tintoré
- 2 Department of Neurosurgery, Maastricht University Medical Center , Maastricht, the Netherlands .,6 Department of Medical Science, Faculty of Medicine, University of Girona (UdG) , Girona, Spain
| | - Hailiang Mei
- 7 Sequencing Analysis Support Core, Leiden University Medical Center , Leiden, the Netherlands
| | - Yasin Temel
- 2 Department of Neurosurgery, Maastricht University Medical Center , Maastricht, the Netherlands .,3 European Graduate School of Neuroscience (EURON) , Maastricht, the Netherlands
| | - Ali Jahanshahi
- 2 Department of Neurosurgery, Maastricht University Medical Center , Maastricht, the Netherlands .,3 European Graduate School of Neuroscience (EURON) , Maastricht, the Netherlands
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29
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Seong KJ, Kim HJ, Cai B, Kook MS, Jung JY, Kim WJ. Toll-like receptor 2 promotes neurogenesis from the dentate gyrus after photothrombotic cerebral ischemia in mice. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2018; 22:145-153. [PMID: 29520167 PMCID: PMC5840073 DOI: 10.4196/kjpp.2018.22.2.145] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/03/2017] [Accepted: 12/07/2017] [Indexed: 01/27/2023]
Abstract
The subgranular zone (SGZ) of hippocampal dentate gyrus (HDG) is a primary site of adult neurogenesis. Toll-like receptors (TLRs), are involved in neural system development of Drosophila and innate immune response of mammals. TLR2 is expressed abundantly in neurogenic niches such as adult mammalian hippocampus. It regulates adult hippocampal neurogenesis. However, the role of TLR2 in adult neurogenesis is not well studied in global or focal cerebral ischemia. Therefore, this study aimed to investigate the role of TLR2 in adult neurogenesis after photochemically induced cerebral ischemia. At 7 days after photothrombotic ischemic injury, the number of bromodeoxyuridine (BrdU)-positive cells was increased in both TLR2 knock-out (KO) mice and wild-type (WT) mice. However, the increment rate of BrdU-positive cells was lower in TLR2 KO mice compared to that in WT mice. The number of doublecortin (DCX) and neuronal nuclei (NeuN)-positive cells in HDG was decreased after photothrombotic ischemia in TLR2 KO mice compared to that in WT mice. The survival rate of cells in HDG was decreased in TLR2 KO mice compared to that in WT mice. In contrast, the number of cleaved-caspase 3 (apoptotic marker) and the number of GFAP (glia marker)/BrdU double-positive cells in TLR2 KO mice were higher than that in WT mice. These results suggest that TLR2 can promote adult neurogenesis from neural stem cell of hippocampal dentate gyrus through increasing proliferation, differentiation, and survival from neural stem cells after ischemic injury of the brain.
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Affiliation(s)
- Kyung-Joo Seong
- Dental Science Research Institute, Department of Oral Physiology, School of Dentistry, Chonnam National University, Gwangju 61186, Korea
| | - Hyeong-Jun Kim
- Dental Science Research Institute, Department of Oral Physiology, School of Dentistry, Chonnam National University, Gwangju 61186, Korea
| | - Bangrong Cai
- Dental Science Research Institute, Department of Oral Physiology, School of Dentistry, Chonnam National University, Gwangju 61186, Korea
| | - Min-Suk Kook
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Chonnam National University, Gwangju 61186, Korea
| | - Ji-Yeon Jung
- Dental Science Research Institute, Department of Oral Physiology, School of Dentistry, Chonnam National University, Gwangju 61186, Korea
| | - Won-Jae Kim
- Dental Science Research Institute, Department of Oral Physiology, School of Dentistry, Chonnam National University, Gwangju 61186, Korea
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30
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RAGE-TLR Crosstalk Sustains Chronic Inflammation in Neurodegeneration. Mol Neurobiol 2017; 55:1463-1476. [PMID: 28168427 DOI: 10.1007/s12035-017-0419-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 01/24/2017] [Indexed: 01/10/2023]
Abstract
Chronic inflammatory reactions are consistenly present in neurodegeneration of Alzheimer type and are considered important factors that accelerate progression of the disease. Receptors of innate immunity participate in triggering and driving inflammatory reactions. For example, Toll-like receptors (TLRs) and receptor for advanced glycation end product (RAGE), major receptors of innate immunity, play a central role in perpetuation of inflammation. RAGE activation should be perceived as a primary mechanism which determines self-perpetuated chronic inflammation, and RAGE cooperation with TLRs amplifies inflammatory signaling. In this review, we highlight and discuss that RAGE-TLR crosstalk emerges as an important driving force of chronic inflammation in Alzheimer's disease.
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Tasiemski A, Salzet M. Neuro-immune lessons from an annelid: The medicinal leech. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 66:33-42. [PMID: 27381717 DOI: 10.1016/j.dci.2016.06.026] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 06/09/2016] [Accepted: 06/30/2016] [Indexed: 06/06/2023]
Abstract
An important question that remains unanswered is how the vertebrate neuroimmune system can be both friend and foe to the damaged nervous tissue. Some of the difficulty in obtaining responses in mammals probably lies in the conflation in the central nervous system (CNS), of the innate and adaptive immune responses, which makes the vertebrate neuroimmune response quite complex and difficult to dissect. An alternative strategy for understanding the relation between neural immunity and neural repair is to study an animal devoid of adaptive immunity and whose CNS is well described and regeneration competent. The medicinal leech offers such opportunity. If the nerve cord of this annelid is crushed or partially cut, axons grow across the lesion and conduction of signals through the damaged region is restored within a few days, even when the nerve cord is removed from the animal and maintained in culture. When the mammalian spinal cord is injured, regeneration of normal connections is more or less successful and implies multiple events that still remain difficult to resolve. Interestingly, the regenerative process of the leech lesioned nerve cord is even more successful under septic than under sterile conditions suggesting that a controlled initiation of an infectious response may be a critical event for the regeneration of normal CNS functions in the leech. Here are reviewed and discussed data explaining how the leech nerve cord sensu stricto (i.e. excluding microglia and infiltrated blood cells) recognizes and responds to microbes and mechanical damages.
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Affiliation(s)
- Aurélie Tasiemski
- Université de Lille, CNRS UMR8198, Unité d'Evolution, Ecologie et Paléontologie (EEP), Species Interactions and Comparative Immunology (SPICI) Team, 59655 Villeneuve d'Ascq, France.
| | - Michel Salzet
- Université de Lille, INSERM U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), 59655 Villeneuve d'Ascq, France
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32
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Paul AM, Acharya D, Le L, Wang P, Stokic DS, Leis AA, Alexopoulou L, Town T, Flavell RA, Fikrig E, Bai F. TLR8 Couples SOCS-1 and Restrains TLR7-Mediated Antiviral Immunity, Exacerbating West Nile Virus Infection in Mice. THE JOURNAL OF IMMUNOLOGY 2016; 197:4425-4435. [PMID: 27798161 DOI: 10.4049/jimmunol.1600902] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/29/2016] [Indexed: 12/11/2022]
Abstract
West Nile virus (WNV) is a neurotropic ssRNA flavivirus that can cause encephalitis, meningitis, and death in humans and mice. Human TLR7 and TLR8 and mouse TLR7 recognize viral ssRNA motifs and induce antiviral immunity. However, the role of mouse TLR8 in antiviral immunity is poorly understood. In this article, we report that TLR8-deficient (Tlr8-/-) mice were resistant to WNV infection compared with wild-type controls. Efficient WNV clearance and moderate susceptibility to WNV-mediated neuronal death in Tlr8-/- mice were attributed to overexpression of Tlr7 and IFN-stimulated gene-56 expression, whereas reduced expression of the proapoptotic gene coding Bcl2-associated X protein was observed. Interestingly, suppressor of cytokine signaling (SOCS)-1 directly associated with TLR8, but not with TLR7, indicating a novel role for TLR8 regulation of SOCS-1 function, whereas selective small interfering RNA knockdown of Socs-1 resulted in induced IFN-stimulated gene-56 and Tlr7 expression following WNV infection. Collectively, we report that TLR8 coupling with SOCS-1 inhibits TLR7-mediated antiviral immunity during WNV infection in mice.
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Affiliation(s)
- Amber M Paul
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS 39406
| | - Dhiraj Acharya
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS 39406
| | - Linda Le
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS 39406
| | - Penghua Wang
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520.,Department of Microbiology and Immunology, School of Medicine, New York Medical College, Valhalla, NY 10595
| | - Dobrivoje S Stokic
- Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, Jackson, MS 39216
| | - A Arturo Leis
- Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, Jackson, MS 39216
| | - Lena Alexopoulou
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, INSERM, U1104, CNRS UMR7280, 13288 Marseille, France
| | - Terrence Town
- Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033
| | - Richard A Flavell
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520; and.,Howard Hughes Medical Institute, New Haven, CT 06520
| | - Erol Fikrig
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520.,Howard Hughes Medical Institute, New Haven, CT 06520
| | - Fengwei Bai
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS 39406;
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Guan Z, Hellman J, Schumacher M. Contemporary views on inflammatory pain mechanisms: TRPing over innate and microglial pathways. F1000Res 2016; 5. [PMID: 27781082 PMCID: PMC5054801 DOI: 10.12688/f1000research.8710.1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/27/2016] [Indexed: 12/14/2022] Open
Abstract
Tissue injury, whether by trauma, surgical intervention, metabolic dysfunction, ischemia, or infection, evokes a complex cellular response (inflammation) that is associated with painful hyperalgesic states. Although in the acute stages it is necessary for protective reflexes and wound healing, inflammation may persist well beyond the need for tissue repair or survival. Prolonged inflammation may well represent the greatest challenge mammalian organisms face, as it can lead to chronic painful conditions, organ dysfunction, morbidity, and death. The complexity of the inflammatory response reflects not only the inciting event (infection, trauma, surgery, cancer, or autoimmune) but also the involvement of heterogeneous cell types including neuronal (primary afferents, sensory ganglion, and spinal cord), non-neuronal (endothelial, keratinocytes, epithelial, and fibroblasts), and immune cells. In this commentary, we will examine 1.) the expression and regulation of two members of the transient receptor potential family in primary afferent nociceptors and their activation/regulation by products of inflammation, 2.) the role of innate immune pathways that drive inflammation, and 3.) the central nervous system’s response to injury with a focus on the activation of spinal microglia driving painful hyperalgesic states.
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Affiliation(s)
- Zhonghui Guan
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA, USA
| | - Judith Hellman
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA, USA
| | - Mark Schumacher
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA, USA
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Yeom JS, Park CH. White matter injury following rotavirus infection in neonates: new aspects to a forgotten entity, 'fifth day fits'? KOREAN JOURNAL OF PEDIATRICS 2016; 59:285-91. [PMID: 27588028 PMCID: PMC5007423 DOI: 10.3345/kjp.2016.59.7.285] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 09/08/2015] [Accepted: 09/09/2015] [Indexed: 11/27/2022]
Abstract
That rotavirus infection can cause neurological symptoms in young children has been well established. However, it is surprising why rotavirus infection has been overlooked as a cause of neonatal seizures for many years, despite significant research interest in neonatal rotavirus infection. Neonates are the age group most vulnerable to seizures, which are typically attributed to a wide range of causes. By contrast, because rotavirus infection is usually asymptomatic, it has been difficult to identify an association between this virus and neonatal seizures. The conventional wisdom has been that, although neonates are commonly infected with rotavirus, neurological complications are rare in this age. However, recent studies using diffusion-weighted imaging (DWI) have suggested a connection between rotavirus infection and neonatal seizures and that rotavirus infection can induce diffuse white matter injury without direct invasion of the central nervous system. The clinical features of white matter injury in rotavirus-infected neonates include the onset of seizures at days 4–6 of life in apparently healthy term infants. The recent findings seem to contradict the conventional wisdom. However, white matter injury might not be a completely new aspect of rotavirus infection in neonates, considering the forgotten clinical entity of neonatal seizures, 'fifth day fits'. With increased use of DWI in neonatal seizures, we are just starting to understand connection between viral infection and white matter injury in neonates. In this review, we discuss the historical aspects of rotavirus infection and neonatal seizures. We also present the clinical features of white matter injury in neonatal rotavirus infection.
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Affiliation(s)
- Jung Sook Yeom
- Department of Pediatrics, Gyeongsang National University School of Medicine, Gyeongsang Institute of Health Science, Jinju, Korea
| | - Chan-Hoo Park
- Department of Pediatrics, Gyeongsang National University School of Medicine, Gyeongsang Institute of Health Science, Jinju, Korea
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35
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Yang Y, Tong M, Yi L, Cheng Y, Zhang M, Cao Z, Wang J, Lin P, Cheng S. Identification and characterization of the toll-like receptor 8 gene in the Chinese raccoon dog (Nyctereutes procyonoides). Immunol Lett 2016; 178:50-60. [PMID: 27481482 DOI: 10.1016/j.imlet.2016.07.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 07/11/2016] [Accepted: 07/25/2016] [Indexed: 10/21/2022]
Abstract
TLR8 is an important sensor of single-stranded RNA (ssRNA) from the viral genome and plays an essential role in innate antiviral responses via the recognition of conserved viral molecular patterns. In this report, TLR8 in the Chinese raccoon dog was characterized and analyzed for the first time. The full-length sequence of raccoon dog TLR8 (RdTLR8) cDNA was cloned by rapid amplification of cDNA ends (RACE) and is 3191bp with a 3117-bp open reading frame (ORF) encoding 1038 amino acids. The putative protein exhibits typical features of the TLR families, with 19 leucine-rich repeats (LRRs) in the extracellular domain and a cytoplasmic TIR domain. Comparative analyses of the RdTLR8 amino acid sequence indicated a 73.6-99.4% sequence identity with dog, horse, pig, sheep, cattle, human and mouse TLR8. Phylogenetic analysis grouped 71 mammalian TLR proteins into five sub-families, wherein RdTLR8 was clustered into a monophyletic TLR8 clade in the TLR9 family, which was completely coincident with the evolutionary relationship among mammals. Quantitative real-time PCR analysis revealed extensive expression of RdTLR8 in tissues from healthy Chinese raccoon dogs with the highest expression in the peripheral blood mononuclear cells (PBMCs) and the lowest expression in the skeletal muscle. HEK293 cells cotransfected with a RdTLR8 expression plasmid and an NF-κB-luciferase reporter plasmid significantly responded to the agonist 3M-002, indicating a functional TLR8 homolog. In addition, raccoon dog PBMCs exposed to the canine distemper virus (CDV) wild strain CDV-PS and the TLR8 agonist 3M-002 showed significant upregulation of RdTLR8 mRNA and proinflammatory cytokines TNF-α and IFN-α, suggesting that RdTLR8 might play an important role in the immune response to viral infections in the Chinese raccoon dog.
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Affiliation(s)
- Yong Yang
- Wu Xi Medical School, Jiangnan University, China; Institute of Special Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, China
| | - Mingwei Tong
- Institute of Special Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, China
| | - Li Yi
- Institute of Special Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, China
| | - Yuening Cheng
- Institute of Special Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, China
| | - Miao Zhang
- Institute of Special Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, China
| | - Zhigang Cao
- Institute of Special Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, China
| | - Jianke Wang
- Institute of Special Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, China
| | - Peng Lin
- Institute of Special Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, China
| | - Shipeng Cheng
- Institute of Special Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, China.
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36
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Alvarado AG, Lathia JD. Taking a Toll on Self-Renewal: TLR-Mediated Innate Immune Signaling in Stem Cells. Trends Neurosci 2016; 39:463-471. [PMID: 27155992 DOI: 10.1016/j.tins.2016.04.005] [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: 11/13/2015] [Revised: 04/07/2016] [Accepted: 04/11/2016] [Indexed: 02/07/2023]
Abstract
Innate immunity has evolved as the front-line cellular defense mechanism to acutely sense and decisively respond to microenvironmental alterations. The Toll-like receptor (TLR) family activates signaling pathways in response to stimuli and is well-characterized in both resident and infiltrating immune cells during neural inflammation, injury, and degeneration. Innate immune signaling has also been observed in neural cells during development and disease, including in the stem and progenitor cells that build the brain and are responsible for its homeostasis. Recently, the activation of developmental programs in malignant brain tumors has emerged as a driver for growth via cancer stem cells. In this review we discuss how innate immune signaling interfaces with stem cell maintenance in the normal and neoplastic brain.
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Affiliation(s)
- Alvaro G Alvarado
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA
| | - Justin D Lathia
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA; Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Cleveland Clinic, Cleveland, OH, USA; Case Comprehensive Cancer Center, Cleveland, OH, USA.
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37
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García Bueno B, Caso JR, Madrigal JLM, Leza JC. Innate immune receptor Toll-like receptor 4 signalling in neuropsychiatric diseases. Neurosci Biobehav Rev 2016; 64:134-47. [PMID: 26905767 DOI: 10.1016/j.neubiorev.2016.02.013] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 11/27/2015] [Accepted: 02/12/2016] [Indexed: 02/08/2023]
Abstract
The innate immunity is a stereotyped first line of defense against pathogens and unspecified damage signals. One of main actors of innate immunity are the Toll-like receptors (TLRs), and one of the better characterized members of this family is TLR-4, that it is mainly activated by Gram-negative bacteria lipopolysaccharide. In brain, TLR-4 organizes innate immune responses against infections or cellular damage, but also possesses other physiological functions. In the last years, some evidences suggest a role of TLR-4 in stress and stress-related neuropsychiatric diseases. Peripheral and brain TLR-4 activation triggers sickness behavior, and its expression is a risk factor of depression. Some elements of the TLR-4 signaling pathway are up-regulated in peripheral samples and brain post-mortem tissue from depressed and suicidal patients. The "leaky gut" hypothesis of neuropsychiatric diseases is based on the existence of an increase of the intestinal permeability which results in bacterial translocation able to activate TLR-4. Enhanced peripheral TLR-4 expression/activity has been described in subjects diagnosed with schizophrenia, bipolar disorder and in autistic children. A role for TLR-4 in drugs abuse has been also proposed. The therapeutic potential of pharmacological/genetic modulation of TLRs signaling pathways in neuropsychiatry is promising, but a great preclinical/clinical scientific effort is still needed.
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Affiliation(s)
- B García Bueno
- Department of Pharmacology, School of Medicine, Complutense University, CIBERSAM, Instituto de Investigación Hospital 12 de Octubre (Imas12), 28040 Madrid, Spain.
| | - J R Caso
- Department of Pharmacology, School of Medicine, Complutense University, CIBERSAM, Instituto de Investigación Hospital 12 de Octubre (Imas12), 28040 Madrid, Spain.
| | - J L M Madrigal
- Department of Pharmacology, School of Medicine, Complutense University, CIBERSAM, Instituto de Investigación Hospital 12 de Octubre (Imas12), 28040 Madrid, Spain.
| | - J C Leza
- Department of Pharmacology, School of Medicine, Complutense University, CIBERSAM, Instituto de Investigación Hospital 12 de Octubre (Imas12), 28040 Madrid, Spain.
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38
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Too LK, McGregor IS, Baxter AG, Hunt NH. Altered behaviour and cognitive function following combined deletion of Toll-like receptors 2 and 4 in mice. Behav Brain Res 2016; 303:1-8. [PMID: 26774978 DOI: 10.1016/j.bbr.2016.01.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 01/05/2016] [Accepted: 01/09/2016] [Indexed: 10/22/2022]
Abstract
Activation of the immune system due to infection or aging is increasingly linked to impaired neuropsychological function. Toll-like receptors 2 and 4 (TLR2, TLR4) are well-characterised for their role in inflammatory events, and their combined activation has been implicated in neurological diseases. We therefore determined whether TLR2 and TLR4 double gene knockout (GKO) mice showed modified behaviour and cognitive function during a 16-day test sequence that employed the automated IntelliCage test system. The IntelliCage features a home cage environment in which groups of mice live and where water reward is gained through performing various tasks centred on drinking stations in each corner of the apparatus. All mice were tested twice, one month apart (the first sequence termed "R1"and the second "R2"). There were fewer corner visits and nosepokes in TLR2/4 GKO compared to wild-type mice during early exploration in R1, suggesting elevated neophobia in GKO mice. Reduced exploration persisted over subsequent test modules during the dark phase. TLR2/4 GKO mice also displayed increased corner visits during drinking sessions compared to non-drinking sessions, but this was not associated with increased drinking. In subsequent, more complex test modules, TLR2/4 GKO mice had unimpaired spatial learning, but showed markedly poorer performance in a visual discrimination reversal task compared to wild-type mice. These results indicated subtle impairments in behaviour and cognitive functions due to double deficiency in TLR2 and TLR4. These finding are highly relevant to understanding the combined actions of TLR2 and TLR4 on neurological status in a range of different disease conditions.
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Affiliation(s)
- Lay Khoon Too
- Molecular Immunopathology Unit, Bosch Institute and School of Medical Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Iain S McGregor
- School of Psychology, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Alan G Baxter
- Comparative Genomics Centre, James Cook University, Townsville, Queensland 4811, Australia
| | - Nicholas H Hunt
- Molecular Immunopathology Unit, Bosch Institute and School of Medical Sciences, University of Sydney, Sydney, New South Wales 2006, Australia.
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39
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Li T, He X, Jia H, Chen G, Zeng S, Fang Y, Jin Q, Jing Z. Molecular cloning and functional characterization of murine toll‑like receptor 8. Mol Med Rep 2015; 13:1119-26. [PMID: 26676274 PMCID: PMC4732850 DOI: 10.3892/mmr.2015.4668] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 11/05/2015] [Indexed: 01/26/2023] Open
Abstract
Toll-like receptors (TLRs) are a large family of germ-line encoded pattern recognition receptors (PRRs) that recognize pathogen-associated molecular patterns and evoke the relevant innate immune responses. TLR8 is a member of several endosome nucleic acid-sensing TLRs; however little attention has been paid to murine TLR8 (mTLR8) compared with other endosome nucleic acid-sensing TLRs. In the present study, mTLR8 was cloned using reverse transcription-polymerase chain reaction from murine peripheral blood mononuclear cells and its function in regulating innate immune response was characterized. The open reading frame of mTLR8 consists of 3,099 bps and encodes 1,032 amino acids. It contains typical leucine-rich repeats, a transmembrane domain and a Toll/interleukin-1 receptor domain, and it shares a high level of identity with other mammalian species. The expression of mTLR8 has been widely observed in different tissues, and higher expression levels of mTLR8 have mainly been detected in the heart, spleen and lung. Overexpression of mTLR8 is required for the activation of transcription factor nuclear factor-κB and the production of tumor necrosis factor-α. However, mTLR8 is not able to activate interferon regulatory factor 3 or activator protein 1, nor can it induce interferon-α in HEK293T cells. These results indicate that mTLR8, as an important PRR, is indeed functional and is vital role in the activation of innate immune responses. This study may aid in determining the molecular basis of the interactions between mTLR8 and pathogens.
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Affiliation(s)
- Tingting Li
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
| | - Xiaobing He
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
| | - Huaijie Jia
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
| | - Guohua Chen
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
| | - Shuang Zeng
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
| | - Yongxiang Fang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
| | - Qiwang Jin
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
| | - Zhizhong Jing
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
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40
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Mukherjee P, Winkler CW, Taylor KG, Woods TA, Nair V, Khan BA, Peterson KE. SARM1, Not MyD88, Mediates TLR7/TLR9-Induced Apoptosis in Neurons. THE JOURNAL OF IMMUNOLOGY 2015; 195:4913-21. [PMID: 26423149 DOI: 10.4049/jimmunol.1500953] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 09/08/2015] [Indexed: 01/09/2023]
Abstract
Neuronal apoptosis is a key aspect of many different neurologic diseases, but the mechanisms remain unresolved. Recent studies have suggested a mechanism of innate immune-induced neuronal apoptosis through the stimulation of endosomal TLRs in neurons. TLRs are stimulated both by pathogen-associated molecular patterns as well as by damage-associated molecular patterns, including microRNAs released by damaged neurons. In the present study, we identified the mechanism responsible for TLR7/TLR9-mediated neuronal apoptosis. TLR-induced apoptosis required endosomal localization of TLRs but was independent of MyD88 signaling. Instead, apoptosis required the TLR adaptor molecule SARM1, which localized to the mitochondria following TLR activation and was associated with mitochondrial accumulation in neurites. Deficiency in SARM1 inhibited both mitochondrial accumulation in neurites and TLR-induced apoptosis. These studies identify a non-MyD88 pathway of TLR7/ TLR9 signaling in neurons and provide a mechanism for how innate immune responses in the CNS directly induce neuronal damage.
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Affiliation(s)
- Piyali Mukherjee
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840; and
| | - Clayton W Winkler
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840; and
| | - Katherine G Taylor
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840; and
| | - Tyson A Woods
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840; and
| | - Vinod Nair
- Research Technologies Branch, Microscopy Unit, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840
| | - Burhan A Khan
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840; and
| | - Karin E Peterson
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840; and
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Kigerl KA, de Rivero Vaccari JP, Dietrich WD, Popovich PG, Keane RW. Pattern recognition receptors and central nervous system repair. Exp Neurol 2014; 258:5-16. [PMID: 25017883 DOI: 10.1016/j.expneurol.2014.01.001] [Citation(s) in RCA: 329] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 12/31/2013] [Accepted: 01/02/2014] [Indexed: 12/12/2022]
Abstract
Pattern recognition receptors (PRRs) are part of the innate immune response and were originally discovered for their role in recognizing pathogens by ligating specific pathogen associated molecular patterns (PAMPs) expressed by microbes. Now the role of PRRs in sterile inflammation is also appreciated, responding to endogenous stimuli referred to as "damage associated molecular patterns" (DAMPs) instead of PAMPs. The main families of PRRs include Toll-like receptors (TLRs), Nod-like receptors (NLRs), RIG-like receptors (RLRs), AIM2-like receptors (ALRs), and C-type lectin receptors. Broad expression of these PRRs in the CNS and the release of DAMPs in and around sites of injury suggest an important role for these receptor families in mediating post-injury inflammation. Considerable data now show that PRRs are among the first responders to CNS injury and activation of these receptors on microglia, neurons, and astrocytes triggers an innate immune response in the brain and spinal cord. Here we discuss how the various PRR families are activated and can influence injury and repair processes following CNS injury.
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Affiliation(s)
- Kristina A Kigerl
- Department of Neuroscience - Center for Brain and Spinal Cord Repair, Wexner Medical Center at The Ohio State University, USA
| | | | - W Dalton Dietrich
- Department of Neurological Surgery - The Miami Project to Cure Paralysis, USA
| | - Phillip G Popovich
- Department of Neuroscience - Center for Brain and Spinal Cord Repair, Wexner Medical Center at The Ohio State University, USA.
| | - Robert W Keane
- Department of Physiology & Biophysics - University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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Lee KY, Oh KW, Weon YC, Choi SH. Neonatal seizures accompanied by diffuse cerebral white matter lesions on diffusion-weighted imaging are associated with rotavirus infection. Eur J Paediatr Neurol 2014; 18:624-31. [PMID: 24813656 DOI: 10.1016/j.ejpn.2014.04.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 02/17/2014] [Accepted: 04/06/2014] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND AIMS Some full-term neonates presenting seizures show diffusion-restricted lesions in the cerebral white matter on brain diffusion-weighted imaging (DWI). The purpose of this study was to describe the clinical characteristics and DWI findings in a group of neonates with seizures, white matter lesions on DWI, and a high incidence of rotavirus infection. METHODS Total 30 full-term neonates with seizures were admitted between 2008 and 2010. Of these, 13 (group A) had the following characteristics on brain DWI: (1) diffusion-restricted lesions in the diffuse symmetric cerebral white matter, including the corpus callosum, and (2) no cerebral cortical lesions. The remaining 17 patients (group B) did not exhibit the DWI findings. The clinical characteristics were compared between the 2 groups. RESULTS The 1-min and 5-min Apgar scores ranged between 7 and 10 in all group A patients, whereas the scores were more diverse in the group B patients. Patients' age at seizure onset was 4.6 ± 0.6 days (range, 4-6 days) in group A and 8.3 ± 7.4 days (range, 1-27 days) in group B. Twelve of 13 patients (92.3%) in group A tested positive for stool rotavirus antigen, while only 2 of 12 (16.7%) in group B tested positive (p < 0.001). Six of 10 group A patients showed normal neurodevelopment, but 4 had delayed development between 6 and 30 months. CONCLUSIONS Rotavirus infection should be considered in neonates with seizures accompanied by diffuse cerebral white matter lesions on DWI, particularly around 5 days of life.
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Affiliation(s)
- Kyung Yeon Lee
- Department of Pediatrics, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea
| | - Ki Won Oh
- Department of Pediatrics, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea
| | - Young Cheol Weon
- Department of Radiology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea.
| | - Seong Hoon Choi
- Department of Radiology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea
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Bissel SJ, Winkler CC, DelTondo J, Wang G, Williams K, Wiley CA. Coxsackievirus B4 myocarditis and meningoencephalitis in newborn twins. Neuropathology 2014; 34:429-437. [PMID: 24702280 DOI: 10.1111/neup.12121] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 03/14/2014] [Accepted: 03/16/2014] [Indexed: 11/29/2022]
Abstract
Coxsackievirus B4 (CB4) is a picornavirus associated with a variety of human diseases, including neonatal meningoencephalitis, myocarditis and type 1 diabetes. We report the pathological findings in twin newborns who died during an acute infection. The twins were born 1 month premature but were well and neurologically intact at birth. After a week they developed acute lethal neonatal sepsis and seizures. Histopathology demonstrated meningoencephalitis and severe myocarditis, as well as pancreatitis, adrenal medullitis and nephritis. Abundant CB4 sequences were identified in nucleic acid extracted from the brain and heart. In situ hybridization with probes to CB4 demonstrated infection of neurons, myocardiocytes, endocrine pancreas and adrenal medulla. The distribution of infected cells and immune response is consistent with reported clinical symptomatology where systemic and neurological diseases are the result of CB4 infection of select target cells.
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Affiliation(s)
- Stephanie J Bissel
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Caitlin C Winkler
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Joseph DelTondo
- Allegheny County Medical Examiner, Pittsburgh, Pennsylvania, USA
| | - Guoji Wang
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Karl Williams
- Allegheny County Medical Examiner, Pittsburgh, Pennsylvania, USA
| | - Clayton A Wiley
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Ballard SL, Miller DL, Ganetzky B. Retrograde neurotrophin signaling through Tollo regulates synaptic growth in Drosophila. ACTA ACUST UNITED AC 2014; 204:1157-72. [PMID: 24662564 PMCID: PMC3971753 DOI: 10.1083/jcb.201308115] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The Toll-like receptor Tollo positively regulates growth of the Drosophila larval neuromuscular junction through the JNK pathway after activation by the neurotrophin Spätzle3. Toll-like receptors (TLRs) are best characterized for their roles in mediating dorsoventral patterning and the innate immune response. However, recent studies indicate that TLRs are also involved in regulating neuronal growth and development. Here, we demonstrate that the TLR Tollo positively regulates growth of the Drosophila melanogaster larval neuromuscular junction (NMJ). Tollo mutants exhibited NMJ undergrowth, whereas increased expression of Tollo led to NMJ overgrowth. Tollo expression in the motoneuron was both necessary and sufficient for regulating NMJ growth. Dominant genetic interactions together with altered levels of phosphorylated c-Jun N-terminal kinase (JNK) and puc-lacZ expression revealed that Tollo signals through the JNK pathway at the NMJ. Genetic interactions also revealed that the neurotrophin Spätzle3 (Spz3) is a likely Tollo ligand. Spz3 expression in muscle and proteolytic activation via the Easter protease was necessary and sufficient to promote NMJ growth. These results demonstrate the existence of a novel neurotrophin signaling pathway that is required for synaptic development in Drosophila.
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Affiliation(s)
- Shannon L Ballard
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53705
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45
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A heavy toll on the outcome of ischemic brain stroke. Exp Neurol 2014; 254:166-7. [PMID: 24512751 DOI: 10.1016/j.expneurol.2014.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 01/20/2014] [Accepted: 02/02/2014] [Indexed: 11/24/2022]
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Trotta T, Porro C, Calvello R, Panaro MA. Biological role of Toll-like receptor-4 in the brain. J Neuroimmunol 2014; 268:1-12. [PMID: 24529856 DOI: 10.1016/j.jneuroim.2014.01.014] [Citation(s) in RCA: 154] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 12/12/2013] [Accepted: 01/28/2014] [Indexed: 01/07/2023]
Abstract
The Toll-like receptors (TLRs) are a family of microbe-sensing receptors that play a central role in the regulation of the host immune system. TLR4 has been described in the brain and seems to regulate some physiological processes, such as neurogenesis. TLR4 has also been reported to play a role during neurodegenerative disorders, including Alzheimer's disease, amyotrophic lateral sclerosis, multiple sclerosis and Parkinson's disease. This review is focused on reports concerning recent insights into the role and activation mechanisms of TLR4 in the brain, in pathological and physiological conditions, as well as the therapeutic benefit that could derive from TLR4 modulation.
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Affiliation(s)
- Teresa Trotta
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy.
| | - Chiara Porro
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Rosa Calvello
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Maria Antonietta Panaro
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
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Okun E, Griffioen KJ, Sarah R, Wan R, Cong WN, De Cabo R, Montalvo AM, Levette A, Maudsley S, Martin B, Arumugam TV, Mattson MP. Toll-like receptors 2 and 4 modulate autonomic control of heart rate and energy metabolism. Brain Behav Immun 2014; 36:90-100. [PMID: 24145051 PMCID: PMC3947180 DOI: 10.1016/j.bbi.2013.10.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Revised: 09/24/2013] [Accepted: 10/12/2013] [Indexed: 02/07/2023] Open
Abstract
Toll-like receptors (TLR) are innate immune receptors typically activated by microbial-associated molecular patterns (MAMPs) during infection or damage-associated molecular patterns (DAMPs) as a result of tissue injury. Recent findings suggest that TLR2 and TLR4 signaling play important roles in developmental and adult neuroplasticity, and in learning and memory. In addition, activation of TLR2 and TLR4 worsens ischemic injury to the heart and brain in animal models of myocardial infarction and stroke. TLR activation is also implicated in thermoregulation and fever in response to infection. However, it is not known whether TLRs participate in the regulation of the sympathetic and/or parasympathetic components of the autonomic nervous system (ANS). Here we provide evidence that TLR2 and TLR4 influence autonomic regulation of heart rate (HR) body temperature and energy metabolism in mice. We show that mice lacking TLR2 or TLR4 exhibit reduced basal HR, which results from an increase of parasympathetic tone. In addition, thermoregulatory responses to stress are altered in TLR2-/- and TLR4-/- mice, and brown fat-dependent thermoregulation is altered in TLR4-/- mice. Moreover, TLR2-/- and TLR4-/- mice consume less food and exhibit a greater mass compared to wild type mice. Collectively, our findings suggest important roles for TLR2 and TLR4 in the ANS regulation of cardiovascular function, thermoregulation, and energy metabolism.
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Affiliation(s)
- Eitan Okun
- The Mina and Everard Goodman Faculty of Life Sciences, The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan 52900, Israel.
| | - Kathleen J. Griffioen
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, 21224, USA
| | - Rothman Sarah
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, 21224, USA
| | - Ruiqian Wan
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, 21224, USA
| | - Wei-Na Cong
- Laboratory of Clinical Investigation, National Institute on Aging, Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Rafael De Cabo
- Translational Gerontology Branch, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Alejandro Martin Montalvo
- Translational Gerontology Branch, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Andrew Levette
- Translational Gerontology Branch, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Stuart Maudsley
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, 21224, USA
| | - Bronwen Martin
- Laboratory of Clinical Investigation, National Institute on Aging, Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224, USA
| | | | - Mark P. Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, 21224, USA,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205
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Tang SC, Yeh SJ, Li YI, Wang YC, Baik SH, Santro T, Widiapradja A, Manzanero S, Sobey CG, Jo DG, Arumugam TV, Jeng JS. Evidence for a detrimental role of TLR8 in ischemic stroke. Exp Neurol 2013; 250:341-7. [DOI: 10.1016/j.expneurol.2013.10.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 09/26/2013] [Accepted: 10/17/2013] [Indexed: 10/26/2022]
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Mukherjee P, Woods TA, Moore RA, Peterson KE. Activation of the innate signaling molecule MAVS by bunyavirus infection upregulates the adaptor protein SARM1, leading to neuronal death. Immunity 2013; 38:705-16. [PMID: 23499490 DOI: 10.1016/j.immuni.2013.02.013] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 02/25/2013] [Indexed: 01/30/2023]
Abstract
La Crosse virus (LACV), a zoonotic Bunyavirus, is a major cause of pediatric viral encephalitis in the United States. A hallmark of neurological diseases caused by LACV and other encephalitic viruses is the induction of neuronal cell death. Innate immune responses have been implicated in neuronal damage, but no mechanism has been elucidated. By using in vitro studies in primary neurons and in vivo studies in mice, we have shown that LACV infection induced the RNA helicase, RIG-I, and mitochondrial antiviral signaling protein (MAVS) signaling pathway, resulting in upregulation of the sterile alpha and TIR-containing motif 1 (SARM1), an adaptor molecule that we found to be directly involved in neuronal damage. SARM1-mediated cell death was associated with induced oxidative stress response and mitochondrial damage. These studies provide an innate-immune signaling mechanism for virus-induced neuronal death and reveal potential targets for development of therapeutics to treat encephalitic viral infections.
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Affiliation(s)
- Piyali Mukherjee
- Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 S. 4th Street, Hamilton, MT 59840, USA
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Abstract
Here, we synthesize research behind the emerging hypothesis that inflammation--which can result, for example, from viral infections--can initiate and propagate chronic neuronal dysfunction, an event that precedes the clinical onset of many neurodegenerative diseases. Therapeutic approaches that target immunological pathways in the prodromal phase of diseases might decrease the incidence of neurodegenerative disorders and increase the therapeutic window for neuroprotection.
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