1
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Wang XP, Guo W, Chen YF, Hong C, Ji J, Zhang XY, Dong YF, Sun XL. PD-1/PD-L1 axis is involved in the interaction between microglial polarization and glioma. Int Immunopharmacol 2024; 133:112074. [PMID: 38615383 DOI: 10.1016/j.intimp.2024.112074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/01/2024] [Accepted: 04/09/2024] [Indexed: 04/16/2024]
Abstract
The tumor microenvironment plays a vital role in glioblastoma growth and invasion. PD-1 and PD-L1 modulate the immunity in the brain tumor microenvironment. However, the underlying mechanisms remain unclear. In the present study, in vivo and in vitro experiments were conducted to reveal the effects of PD-1/PD-L1 on the crosstalk between microglia and glioma. Results showed that glioma cells secreted PD-L1 to the peritumoral areas, particularly microglia containing highly expressed PD-1. In the early stages of glioma, microglia mainly polarized into the pro-inflammatory subtype (M1). Subsequently, the secreted PD-L1 accumulated and bound to PD-1 on microglia, facilitating their polarization toward the microglial anti-inflammatory (M2) subtype primarily via the STAT3 signaling pathway. The role of PD-1/PD-L1 in M2 polarization of microglia was partially due to PD-1/PD-L1 depletion or application of BMS-1166, a novel inhibitor of PD-1/PD-L1. Consistently, co-culturing with microglia promoted glioma cell growth and invasion, and blocking PD-1/PD-L1 significantly suppressed these processes. Our findings reveal that the PD-1/PD-L1 axis engages in the microglial M2 polarization in the glioma microenvironment and promotes tumor growth and invasion.
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Affiliation(s)
- Xi-Peng Wang
- Nanjing University of Chinese Medicine, Nanjing, China; Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, Nanjing, China
| | - Wei Guo
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, Nanjing, China
| | - Ye-Fan Chen
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, Nanjing, China
| | - Chen Hong
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, Nanjing, China
| | - Juan Ji
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, Nanjing, China
| | - Xi-Yue Zhang
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, Nanjing, China
| | - Yin-Feng Dong
- Nanjing University of Chinese Medicine, Nanjing, China.
| | - Xiu-Lan Sun
- Nanjing University of Chinese Medicine, Nanjing, China; Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, Nanjing, China.
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2
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Yamamoto M, Sakai M, Yu Z, Nakanishi M, Yoshii H. Glial Markers of Suicidal Behavior in the Human Brain-A Systematic Review of Postmortem Studies. Int J Mol Sci 2024; 25:5750. [PMID: 38891940 PMCID: PMC11171620 DOI: 10.3390/ijms25115750] [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: 04/15/2024] [Revised: 05/11/2024] [Accepted: 05/14/2024] [Indexed: 06/21/2024] Open
Abstract
Suicide is a major public health priority, and its molecular mechanisms appear to be related to glial abnormalities and specific transcriptional changes. This study aimed to identify and synthesize evidence of the relationship between glial dysfunction and suicidal behavior to understand the neurobiology of suicide. As of 26 January 2024, 46 articles that met the inclusion criteria were identified by searching PubMed and ISI Web of Science. Most postmortem studies, including 30 brain regions, have determined no density or number of total Nissl-glial cell changes in suicidal patients with major psychiatric disorders. There were 17 astrocytic, 14 microglial, and 9 oligodendroglial studies using specific markers of each glial cell and further on their specific gene expression. Those studies suggest that astrocytic and oligodendroglial cells lost but activated microglia in suicides with affective disorder, bipolar disorders, major depression disorders, or schizophrenia in comparison with non-suicided patients and non-psychiatric controls. Although the data from previous studies remain complex and cannot fully explain the effects of glial cell dysfunction related to suicidal behaviors, they provide risk directions potentially leading to suicide prevention.
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Affiliation(s)
- Mana Yamamoto
- Department of Psychiatric Nursing, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Mai Sakai
- Department of Psychiatric Nursing, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Zhiqian Yu
- Department of Psychiatry, Graduate School of Medicine, Tohoku University, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8573, Japan
| | - Miharu Nakanishi
- Department of Psychiatric Nursing, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Hatsumi Yoshii
- Department of Psychiatric Nursing, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
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3
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Wongso H, Kurniawan A, Setiadi Y, Kusumaningrum CE, Widyasari EM, Wibawa TH, Mahendra I, Febrian MB, Sriyani ME, Halimah I, Daruwati I, Gunawan R, Achmad A, Nugraha DH, Lesmana R, Nugraha AS. Translocator Protein 18 kDa (TSPO): A Promising Molecular Target for Image-Guided Surgery of Solid Cancers. Adv Pharm Bull 2024; 14:86-104. [PMID: 38585455 PMCID: PMC10997928 DOI: 10.34172/apb.2024.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/26/2023] [Accepted: 10/08/2023] [Indexed: 04/09/2024] Open
Abstract
The translocator protein 18-kDa (TSPO) is a mitochondrial membrane protein that is previously identified as the peripheral benzodiazepine receptor (PBR). Furthermore, it plays a significant role in a diverse range of biochemical processes, including steroidogenesis, mitochondrial cholesterol transport, cell survival and death, cell proliferation, and carcinogenesis. Several investigations also reported its roles in various types of cancers, including colorectal, brain, breast, prostate, and lung cancers, as well as melanoma. According to a previous study, the expression of TSPO was upregulated in cancer cells, which corresponds to an aggressive phenotype and/or poor prognosis. Consequently, the potential for crafting diagnostic and prognostic tools with a focus on TSPO holds great potential. In this context, several radioligands designed to target this protein have been identified, and some of the candidates have advanced to clinical trials. In recent years, the use of hybrid probes with radioactive and fluorescence molecules for image-guided surgery has exhibited promising results in animal and human studies. This indicates that the approach can serve as a valuable surgical navigator during cancer surgery. The current hybrid probes are built from various molecular platforms, including small molecules, nanoparticles, and antibodies. Although several TSPO-targeted imaging probes have been developed, their development for image-guided surgery of cancers is still limited. Therefore, this review aims to highlight recent findings on the involvement of TSPO in carcinogenesis, as well as provide a new perspective on the potential application of TSPO-targeted hybrid probes for image-guided surgery.
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Affiliation(s)
- Hendris Wongso
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
| | - Ahmad Kurniawan
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Yanuar Setiadi
- Research Center for Environmental and Clean Technology, Research Organization for Life Sciences and Environment, National Research and Innovation Agency, Puspiptek, Banten 15314, Indonesia
| | - Crhisterra E. Kusumaningrum
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Eva M. Widyasari
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Teguh H.A. Wibawa
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Isa Mahendra
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
| | - Muhamad B. Febrian
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Maula E. Sriyani
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Iim Halimah
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Isti Daruwati
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Universitas Padjadjaran, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
| | - Rudi Gunawan
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Universitas Padjadjaran, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
| | - Arifudin Achmad
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
- Department of Nuclear Medicine and Molecular Theranostics, Faculty of Medicine, Universitas Padjadjaran, Bandung 40161
- Oncology and Stem Cells Working Group, Faculty of Medicine, Universitas Padjadjaran, Bandung 40161
| | | | - Ronny Lesmana
- Department of Biomedical Science, Faculty of Medicine, Universitas Padjadjaran, Jatinangor 45363, Indonesia
- Physiology Molecular, Division of Biological Activity, Central Laboratory, Universitas Padjadjaran, Jatinangor 45363, Indonesia
- Laboratory of Sciences, Graduate School, Universitas Padjadjaran, Bandung, Indonesia
| | - Ari S. Nugraha
- Drug Utilisation and Discovery Research Group, Faculty of Pharmacy, Universitas Jember, Jember 68121, Indonesia
- School of Chemistry and Molecular Biosciences, Molecular Horizons, University of Wollongong, Wollongong, New South Wales, 2522, Australia
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4
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Wen B, Pan Y, Cheng J, Xu L, Xu J. The Role of Neuroinflammation in Complex Regional Pain Syndrome: A Comprehensive Review. J Pain Res 2023; 16:3061-3073. [PMID: 37701560 PMCID: PMC10493102 DOI: 10.2147/jpr.s423733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 08/26/2023] [Indexed: 09/14/2023] Open
Abstract
Complex Regional Pain Syndrome (CRPS) is an excess and/or prolonged pain and inflammation condition that follows an injury to a limb. The pathogenesis of CRPS is multifaceted that remains incompletely understood. Neuroinflammation is an inflammatory response in the peripheral and central nervous systems. Dysregulated neuroinflammation plays a crucial role in the initiation and maintenance of pain and nociceptive neuronal sensitization, which may contribute to the transition from acute to chronic pain and the perpetuation of chronic pain in CRPS. The key features of neuroinflammation encompass infiltration and activation of inflammatory cells and the production of inflammatory mediators in both the central and peripheral nervous systems. This article reviews the role of neuroinflammation in the onset and progression of CRPS from six perspectives: neurogenic inflammation, neuropeptides, glial cells, immune cells, cytokines, and keratinocytes. The objective is to provide insights that can inform future research and development of therapeutic targets for CRPS.
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Affiliation(s)
- Bei Wen
- Department of Anesthesiology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, People’s Republic of China
| | - Yinbing Pan
- Department of Anesthesiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, People’s Republic of China
| | - Jianguo Cheng
- Department of Pain Management, Cleveland Clinic, Cleveland, OH, 44195, USA
- Department of Neuroscience, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Li Xu
- Department of Anesthesiology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, People’s Republic of China
| | - Jijun Xu
- Department of Pain Management, Cleveland Clinic, Cleveland, OH, 44195, USA
- Department of Inflammation and Immunity; Cleveland Clinic, Cleveland, OH, 44195, USA
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5
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Tangella AV. Imaging Modalities and Their Findings in Patients With Complex Regional Pain Syndrome: A Review. Cureus 2023; 15:e41747. [PMID: 37575802 PMCID: PMC10415629 DOI: 10.7759/cureus.41747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/11/2023] [Indexed: 08/15/2023] Open
Abstract
Complex regional pain syndrome (CRPS) is a systemic or regional pain pathology associated with the nondermatomal or dermatomal distribution of excruciating intolerable pain, which might be triggered by an insignificant or weak stimulus or sometimes without any. Its symptoms encompass neurological, musculoskeletal, dermatological, and vascular realms. It is usually preceded by an episode of nerve injury or intervention set in numerous circumstances ranging from trauma to surgeries to chronic diseases. CRPS has been shrouded in a veil of mystery and was called a psychological phenomenon without any proper organic basis when it was described by Ambroise Pare initially. This led to disproportionately fewer research investments into this disease. Given the great advancement of diagnostic modalities since its inception, researchers and physicians have been trying to identify the physiological basis for it and have succeeded. Numerous pathophysiological pathways have been involved in this disease, but all of them point toward the possibility of improper pain processing at various levels of the pain pathway along with brain plasticity leading to aberrant neuronal circuitry between different segments of the sensory cortex, basal ganglia, prefrontal cortex, and insula. This paper explores the various studies done to evaluate the role of different imaging modalities, ranging from three-phase bone scintigraphy (TPBS) to diffusion traction imaging (DTI).
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6
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Nutma E, Gebro E, Marzin MC, van der Valk P, Matthews PM, Owen DR, Amor S. Activated microglia do not increase 18 kDa translocator protein (TSPO) expression in the multiple sclerosis brain. Glia 2021; 69:2447-2458. [PMID: 34145928 PMCID: PMC8453709 DOI: 10.1002/glia.24052] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 06/08/2021] [Accepted: 06/09/2021] [Indexed: 12/20/2022]
Abstract
To monitor innate immune responses in the CNS, the 18 kDa Translocator protein (TSPO) is a frequently used target for PET imaging. The frequent assumption that increased TSPO expression in the human CNS reflects pro-inflammatory activation of microglia has been extrapolated from rodent studies. However, TSPO expression does not increase in activated human microglia in vitro. Studies of multiple sclerosis (MS) lesions reveal that TSPO is not restricted to pro-inflammatory microglia/macrophages, but also present in homeostatic or reparative microglia. Here, we investigated quantitative relationships between TSPO expression and microglia/macrophage phenotypes in white matter and lesions of brains with MS pathology. In white matter from brains with no disease pathology, normal appearing white matter (NAWM), active MS lesions and chronic active lesion rims, over 95% of TSPO+ cells are microglia/macrophages. Homeostatic microglial markers in NAWM and control tissue are lost/reduced in active lesions and chronic active lesion rims, reflecting cell activation. Nevertheless, pixel analysis of TSPO+ cells (n = 12,225) revealed that TSPO expression per cell is no higher in active lesions and chronic active lesion rims (where myeloid cells are activated) relative to NAWM and control. This data suggests that whilst almost all the TSPO signal in active lesions, chronic active lesion rims, NAWM and control is associated with microglia/macrophages, their TSPO expression predominantly reflects cell density and not activation phenotype. This finding has implications for the interpretation of TSPO PET signal in MS and other CNS diseases, and further demonstrates the limitation of extrapolating TSPO biology from rodents to humans.
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Affiliation(s)
- Erik Nutma
- Department of Pathology, Amsterdam UMC - Location VUmc, Amsterdam, HV, Netherlands
| | - Emeline Gebro
- Department of Pathology, Amsterdam UMC - Location VUmc, Amsterdam, HV, Netherlands
| | - Manuel C Marzin
- Department of Pathology, Amsterdam UMC - Location VUmc, Amsterdam, HV, Netherlands
| | - Paul van der Valk
- Department of Pathology, Amsterdam UMC - Location VUmc, Amsterdam, HV, Netherlands
| | - Paul M Matthews
- Department of Brain Sciences, Imperial College London, London, UK.,UK Dementia Research Institute, Imperial College London, London, UK
| | - David R Owen
- Department of Brain Sciences, Imperial College London, London, UK
| | - Sandra Amor
- Department of Pathology, Amsterdam UMC - Location VUmc, Amsterdam, HV, Netherlands.,Department of Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine & Dentistry, Queen Mary University of London, London, UK
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7
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Qiao O, Ji H, Zhang Y, Zhang X, Zhang X, Liu N, Huang L, Liu C, Gao W. New insights in drug development for Alzheimer's disease based on microglia function. Biomed Pharmacother 2021; 140:111703. [PMID: 34083109 DOI: 10.1016/j.biopha.2021.111703] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/29/2021] [Accepted: 05/05/2021] [Indexed: 12/26/2022] Open
Abstract
One of the biggest challenges in drug development for Alzheimer's disease (AD) is how to effectively remove deposits of amyloid-beta (Aβ). Recently, the relationship between microglia and Aβ has become a research hotspot. Emerging evidence suggests that Aβ-induced microglia-mediated neuroinflammation further aggravates the decline of cognitive function, while microglia are also involved in the process of Aβ clearance. Hence, microglia have become a potential therapeutic target for the treatment or prevention of AD. An in-depth understanding of the role played by microglia in the development of AD will help us to broaden therapeutic strategies for AD. In this review, we provide an overview of the dual roles of microglia in AD progression: the positive effect of phagocytosis of Aβ and its negative effect on neuroinflammation after over-activation. With the advantages of novel structure, high efficiency, and low toxicity, small-molecule compounds as modulators of microglial function have attracted considerable attention in the therapeutic areas of AD. In this review, we also summarize the therapeutic potential of small molecule compounds (SMCs) and their structure-activity relationship for AD treatment through modulating microglial phagocytosis and inhibiting neuroinflammation. For example, the position and number of phenolic hydroxyl groups on the B ring are the key to the activity of flavonoids, and the substitution of hydroxyl groups on the benzene ring enhances the anti-inflammatory activity of phenolic acids. This review is expected to be useful for developing effective modulators of microglial function from SMCs for the amelioration and treatment of AD.
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Affiliation(s)
- Ou Qiao
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Weijin Road, Tianjin 300072, China
| | - Haixia Ji
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Weijin Road, Tianjin 300072, China
| | - Yi Zhang
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Weijin Road, Tianjin 300072, China
| | - Xinyu Zhang
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Weijin Road, Tianjin 300072, China
| | - Xueqian Zhang
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Weijin Road, Tianjin 300072, China
| | - Na Liu
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Weijin Road, Tianjin 300072, China
| | - Luqi Huang
- Chinese Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Changxiao Liu
- The State Key Laboratories of Pharmacodynamics and Pharmacokinetics, Tianjin 300193, China
| | - Wenyuan Gao
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Weijin Road, Tianjin 300072, China.
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8
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Kasatkina LA, Rittchen S, Sturm EM. Neuroprotective and Immunomodulatory Action of the Endocannabinoid System under Neuroinflammation. Int J Mol Sci 2021; 22:ijms22115431. [PMID: 34063947 PMCID: PMC8196612 DOI: 10.3390/ijms22115431] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/17/2021] [Accepted: 05/18/2021] [Indexed: 12/17/2022] Open
Abstract
Endocannabinoids (eCBs) are lipid-based retrograde messengers with a relatively short half-life that are produced endogenously and, upon binding to the primary cannabinoid receptors CB1/2, mediate multiple mechanisms of intercellular communication within the body. Endocannabinoid signaling is implicated in brain development, memory formation, learning, mood, anxiety, depression, feeding behavior, analgesia, and drug addiction. It is now recognized that the endocannabinoid system mediates not only neuronal communications but also governs the crosstalk between neurons, glia, and immune cells, and thus represents an important player within the neuroimmune interface. Generation of primary endocannabinoids is accompanied by the production of their congeners, the N-acylethanolamines (NAEs), which together with N-acylneurotransmitters, lipoamino acids and primary fatty acid amides comprise expanded endocannabinoid/endovanilloid signaling systems. Most of these compounds do not bind CB1/2, but signal via several other pathways involving the transient receptor potential cation channel subfamily V member 1 (TRPV1), peroxisome proliferator-activated receptor (PPAR)-α and non-cannabinoid G-protein coupled receptors (GPRs) to mediate anti-inflammatory, immunomodulatory and neuroprotective activities. In vivo generation of the cannabinoid compounds is triggered by physiological and pathological stimuli and, specifically in the brain, mediates fine regulation of synaptic strength, neuroprotection, and resolution of neuroinflammation. Here, we review the role of the endocannabinoid system in intrinsic neuroprotective mechanisms and its therapeutic potential for the treatment of neuroinflammation and associated synaptopathy.
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Affiliation(s)
- Ludmila A. Kasatkina
- Otto Loewi Research Center, Division of Pharmacology, Medical University of Graz, 8010 Graz, Austria; (L.A.K.); (S.R.)
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Sonja Rittchen
- Otto Loewi Research Center, Division of Pharmacology, Medical University of Graz, 8010 Graz, Austria; (L.A.K.); (S.R.)
| | - Eva M. Sturm
- Otto Loewi Research Center, Division of Pharmacology, Medical University of Graz, 8010 Graz, Austria; (L.A.K.); (S.R.)
- Correspondence:
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9
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Prasad Md A, Chakravarthy Md K. Review of complex regional pain syndrome and the role of the neuroimmune axis. Mol Pain 2021; 17:17448069211006617. [PMID: 33788654 PMCID: PMC8020088 DOI: 10.1177/17448069211006617] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Background Complex regional pain syndrome (CRPS) is a progressive and painful disease of
the extremities that is characterized by continuous pain inconsistent with
the initial trauma. CRPS is caused by a multi-mechanism process that
involves both the peripheral and central nervous system, with a prominent
role of inflammation in CRPS pathophysiology. This review examines what is
currently known about the CRPS inflammatory and pain mechanisms, as well as
the possible impact of neurostimulation therapies on the neuroimmune axis of
CRPS. Study design A narrative review of preclinical and clinical studies provided an overview
of the pain and inflammatory mechanisms in CRPS and addressed the effect of
neurostimulation on immunomodulation. Methods A systematic literature search was conducted based on the PRISMA guidelines
between September 2015 to September 2020. Data sources included relevant
literature identified through searches of PubMed, Embase and the Cochrane
Database of Systematic Reviews. Results Sixteen preclinical and eight clinical studies were reviewed. Preclinical
studies identified different mechanisms of pain development in the acute and
chronic CRPS phases. Several preclinical and clinical studies investigating
inflammatory mechanisms, autoimmunity, and genetic profiles in CRPS,
supported a role of neuroinflammation in the pathophysiology of CRPS. The
immunomodulatory effects of neurostimulation therapy is still unclear,
despite clinical improvement in the CRPS patients. Conclusions Increasing evidence supports a role for inflammation and neuroinflammation in
CRPS pathophysiology. Preliminary neurostimulation findings, together with
the role of (neuro)inflammation in CRPS, seems to provide a compelling
rationale for its use in CRPS pain treatment. The possible immunomodulatory
effects of neurostimulation opens new therapeutic possibilities, however
further research is needed to gain a better understanding of the working
mechanisms.
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Affiliation(s)
- Amrita Prasad Md
- Axxon Pain, Brisbane Private Hospital, 259 Wickham Terrace, Brisbane, Queensland 4000, Australia
| | - Krishnan Chakravarthy Md
- Division of Pain Medicine, Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA.,Department of Anesthesiology and Pain Medicine, VA San Diego Health Care, San Diego, CA, USA
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10
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Meikle SR, Sossi V, Roncali E, Cherry SR, Banati R, Mankoff D, Jones T, James M, Sutcliffe J, Ouyang J, Petibon Y, Ma C, El Fakhri G, Surti S, Karp JS, Badawi RD, Yamaya T, Akamatsu G, Schramm G, Rezaei A, Nuyts J, Fulton R, Kyme A, Lois C, Sari H, Price J, Boellaard R, Jeraj R, Bailey DL, Eslick E, Willowson KP, Dutta J. Quantitative PET in the 2020s: a roadmap. Phys Med Biol 2021; 66:06RM01. [PMID: 33339012 PMCID: PMC9358699 DOI: 10.1088/1361-6560/abd4f7] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Positron emission tomography (PET) plays an increasingly important role in research and clinical applications, catalysed by remarkable technical advances and a growing appreciation of the need for reliable, sensitive biomarkers of human function in health and disease. Over the last 30 years, a large amount of the physics and engineering effort in PET has been motivated by the dominant clinical application during that period, oncology. This has led to important developments such as PET/CT, whole-body PET, 3D PET, accelerated statistical image reconstruction, and time-of-flight PET. Despite impressive improvements in image quality as a result of these advances, the emphasis on static, semi-quantitative 'hot spot' imaging for oncologic applications has meant that the capability of PET to quantify biologically relevant parameters based on tracer kinetics has not been fully exploited. More recent advances, such as PET/MR and total-body PET, have opened up the ability to address a vast range of new research questions, from which a future expansion of applications and radiotracers appears highly likely. Many of these new applications and tracers will, at least initially, require quantitative analyses that more fully exploit the exquisite sensitivity of PET and the tracer principle on which it is based. It is also expected that they will require more sophisticated quantitative analysis methods than those that are currently available. At the same time, artificial intelligence is revolutionizing data analysis and impacting the relationship between the statistical quality of the acquired data and the information we can extract from the data. In this roadmap, leaders of the key sub-disciplines of the field identify the challenges and opportunities to be addressed over the next ten years that will enable PET to realise its full quantitative potential, initially in research laboratories and, ultimately, in clinical practice.
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Affiliation(s)
- Steven R Meikle
- Sydney School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Australia
- Brain and Mind Centre, The University of Sydney, Australia
| | - Vesna Sossi
- Department of Physics and Astronomy, University of British Columbia, Canada
| | - Emilie Roncali
- Department of Biomedical Engineering, University of California, Davis, United States of America
| | - Simon R Cherry
- Department of Biomedical Engineering, University of California, Davis, United States of America
- Department of Radiology, University of California, Davis, United States of America
| | - Richard Banati
- Sydney School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Australia
- Brain and Mind Centre, The University of Sydney, Australia
- Australian Nuclear Science and Technology Organisation, Sydney, Australia
| | - David Mankoff
- Department of Radiology, University of Pennsylvania, United States of America
| | - Terry Jones
- Department of Radiology, University of California, Davis, United States of America
| | - Michelle James
- Department of Radiology, Molecular Imaging Program at Stanford (MIPS), CA, United States of America
- Department of Neurology and Neurological Sciences, Stanford University, CA, United States of America
| | - Julie Sutcliffe
- Department of Biomedical Engineering, University of California, Davis, United States of America
- Department of Internal Medicine, University of California, Davis, CA, United States of America
| | - Jinsong Ouyang
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, United States of America
| | - Yoann Petibon
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, United States of America
| | - Chao Ma
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, United States of America
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, United States of America
| | - Suleman Surti
- Department of Radiology, University of Pennsylvania, United States of America
| | - Joel S Karp
- Department of Radiology, University of Pennsylvania, United States of America
| | - Ramsey D Badawi
- Department of Biomedical Engineering, University of California, Davis, United States of America
- Department of Radiology, University of California, Davis, United States of America
| | - Taiga Yamaya
- National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan
| | - Go Akamatsu
- National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan
| | - Georg Schramm
- Department of Imaging and Pathology, Nuclear Medicine & Molecular imaging, KU Leuven, Belgium
| | - Ahmadreza Rezaei
- Department of Imaging and Pathology, Nuclear Medicine & Molecular imaging, KU Leuven, Belgium
| | - Johan Nuyts
- Department of Imaging and Pathology, Nuclear Medicine & Molecular imaging, KU Leuven, Belgium
| | - Roger Fulton
- Brain and Mind Centre, The University of Sydney, Australia
- Department of Medical Physics, Westmead Hospital, Sydney, Australia
| | - André Kyme
- Brain and Mind Centre, The University of Sydney, Australia
- School of Biomedical Engineering, Faculty of Engineering and IT, The University of Sydney, Australia
| | - Cristina Lois
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, United States of America
| | - Hasan Sari
- Department of Radiology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
- Athinoula A. Martinos Center, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Julie Price
- Department of Radiology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
- Athinoula A. Martinos Center, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Ronald Boellaard
- Radiology and Nuclear Medicine, Cancer Center Amsterdam, Amsterdam University Medical Center, location VUMC, Netherlands
| | - Robert Jeraj
- Departments of Medical Physics, Human Oncology and Radiology, University of Wisconsin, United States of America
- Faculty of Mathematics and Physics, University of Ljubljana, Slovenia
| | - Dale L Bailey
- Sydney School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Australia
- Department of Nuclear Medicine, Royal North Shore Hospital, Sydney, Australia
- Faculty of Science, The University of Sydney, Australia
| | - Enid Eslick
- Department of Nuclear Medicine, Royal North Shore Hospital, Sydney, Australia
| | - Kathy P Willowson
- Department of Nuclear Medicine, Royal North Shore Hospital, Sydney, Australia
- Faculty of Science, The University of Sydney, Australia
| | - Joyita Dutta
- Department of Electrical and Computer Engineering, University of Massachusetts Lowell, United States of America
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11
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Zhou Q, Guo D, Li X, Wang Y, Ye X, Xue S, Wang X. Anti-inflammatory effects of vinpocetine in LPS-stimulated microglia via activation of AMPK. AN ACAD BRAS CIENC 2020; 92:e20200241. [PMID: 33237143 DOI: 10.1590/0001-3765202020200241] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 06/17/2020] [Indexed: 11/21/2022] Open
Abstract
Microglia are the resident immune cells in the central nervous system (CNS), which play important roles in the repair of neuroinflammatory injury. The present study investigated the anti-neuroinflammatory effects of vinpocetine induced by lipopolysaccharide (LPS) in BV2 microglia. BV2 microglia were pretreated with vinpocetine, and then stimulated with LPS (100 ng/mL). The cytotoxicity of BV2 microglia was assessed by MTT assay. The expression levels of nitrite oxide were measured by Griess assay. Proinflammatory cytokines and mediators were determined by Western blot, ELISA, or quantitative real-time PCR. Vinpocetine significantly decreased the generation of nitric oxide-inducible nitric oxide synthase (iNOS), cyclooxygenase- (COX-) 2 in a dose-dependent manner. In addition, vinpocetine decreased the production of pro-inflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-1β. Furthermore, it was observed that phosphorylation levels of AMPK (Thr-172) decreased in LPS-stimulated BV2 microglia. Vinpocetine treatment increased AMPK phosphorylation in LPS-stimulated BV2 microglia. AMPK inhibition by siRNA blocked the anti-inflammatory effects of vinpocetine induced by LPS in BV2 microglia. The overall results demonstrate that vinpocetine has anti-inflammatory effects on LPS-stimulated BV2 microglia via inducing phosphorylation of AMPK, suggesting that vinpocetine is a potential therapeutic agent in neuroinflammatory injury.
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Affiliation(s)
- Qin Zhou
- Department of Pharmacy, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Suzhou, Jiangsu, 215002, P.R. China
| | - Dongkai Guo
- Department of pharmacy, The Affiliated Suzhou Science and Technology Town Hospital of Nanjing Medical University, Suzhou, Jiangsu, 215153, P.R. China.,Jiangsu Key Laboratory of Neuropsychiatric Diseases Research and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215021, P.R. China
| | - Xinjia Li
- Department of Pharmacy, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Suzhou, Jiangsu, 215002, P.R. China
| | - Yixuan Wang
- Department of Pharmacy, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Suzhou, Jiangsu, 215002, P.R. China
| | - Xiaoli Ye
- Department of Pharmacy, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Suzhou, Jiangsu, 215002, P.R. China
| | - Sudong Xue
- Department of Pharmacy, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Suzhou, Jiangsu, 215002, P.R. China
| | - Xiaoyu Wang
- Department of Pharmacy, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Suzhou, Jiangsu, 215002, P.R. China
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12
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Si XL, Fang YJ, Li LF, Gu LY, Yin XZ, Jun-Tian, Yan YP, Pu JL, Zhang BR. From inflammasome to Parkinson's disease: Does the NLRP3 inflammasome facilitate exosome secretion and exosomal alpha-synuclein transmission in Parkinson's disease? Exp Neurol 2020; 336:113525. [PMID: 33161049 DOI: 10.1016/j.expneurol.2020.113525] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/29/2020] [Accepted: 10/31/2020] [Indexed: 02/06/2023]
Abstract
A pivotal neuropathological manifestation of synucleinopathies, like Parkinson's disease (PD), is the aggregation of α-synuclein. In a recent cell-to-cell transmission model of α-synuclein, α-synuclein propagation was demonstrated to resemble that of prion proteins in the central nervous system. Furthermore, exosomes, as biomolecule carriers, have been shown to transmit α-synuclein from neuron to neuron. However, the mechanisms underlying exosomal α-synuclein transmission have not been well understood. The NLR family pyrin domain containing 3 protein (NLRP3) inflammasome activation in microglia, and the subsequent release of proinflammatory cytokines, are two crucial pathological events involved in neuroinflammation and PD progression. Research has revealed that the NLRP3 inflammasome may facilitate the secretion of extracellular vesicles, as well as exosomal transmission of proteins like aggregated α-synuclein. However, only a few reports have evaluated these pathogenic mechanisms. Herein we evaluate for the first time the current evidence for the involvement of the NLRP3 inflammasome in microvesicle generation by microglial cells, and the various mechanisms regarding the production, shedding, and content of exosomes in relation to α-synuclein transmission from neuron to neuron. Furthermore, we propose a model of microglial NLRP3 inflammasome-dependent exosome secretion and exosomal α-synuclein transmission in PD. This knowledge may lead to the identification of novel potential targets for drug development and stimulate further research in PD.
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Affiliation(s)
- Xiao-Li Si
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China
| | - Yuan-Jian Fang
- Department of Neurosurgery, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China
| | - Ling-Fei Li
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310006, China
| | - Lu-Yan Gu
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China
| | - Xin-Zhen Yin
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China
| | - Jun-Tian
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China
| | - Ya-Ping Yan
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China
| | - Jia-Li Pu
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China.
| | - Bao-Rong Zhang
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China.
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13
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Jurga AM, Paleczna M, Kuter KZ. Overview of General and Discriminating Markers of Differential Microglia Phenotypes. Front Cell Neurosci 2020; 14:198. [PMID: 32848611 PMCID: PMC7424058 DOI: 10.3389/fncel.2020.00198] [Citation(s) in RCA: 478] [Impact Index Per Article: 119.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 06/05/2020] [Indexed: 12/12/2022] Open
Abstract
Inflammatory processes and microglia activation accompany most of the pathophysiological diseases in the central nervous system. It is proven that glial pathology precedes and even drives the development of multiple neurodegenerative conditions. A growing number of studies point out the importance of microglia in brain development as well as in physiological functioning. These resident brain immune cells are divergent from the peripherally infiltrated macrophages, but their precise in situ discrimination is surprisingly difficult. Microglial heterogeneity in the brain is especially visible in their morphology and cell density in particular brain structures but also in the expression of cellular markers. This often determines their role in physiology or pathology of brain functioning. The species differences between rodent and human markers add complexity to the whole picture. Furthermore, due to activation, microglia show a broad spectrum of phenotypes ranging from the pro-inflammatory, potentially cytotoxic M1 to the anti-inflammatory, scavenging, and regenerative M2. A precise distinction of specific phenotypes is nowadays essential to study microglial functions and tissue state in such a quickly changing environment. Due to the overwhelming amount of data on multiple sets of markers that is available for such studies, the choice of appropriate markers is a scientific challenge. This review gathers, classifies, and describes known and recently discovered protein markers expressed by microglial cells in their different phenotypes. The presented microglia markers include qualitative and semi-quantitative, general and specific, surface and intracellular proteins, as well as secreted molecules. The information provided here creates a comprehensive and practical guide through the current knowledge and will facilitate the choosing of proper, more specific markers for detailed studies on microglia and neuroinflammatory mechanisms in various physiological as well as pathological conditions. Both basic research and clinical medicine need clearly described and validated molecular markers of microglia phenotype, which are essential in diagnostics, treatment, and prevention of diseases engaging glia activation.
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Affiliation(s)
- Agnieszka M Jurga
- Maj Institute of Pharmacology, Department of Neuropsychopharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Martyna Paleczna
- Maj Institute of Pharmacology, Department of Neuropsychopharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Katarzyna Z Kuter
- Maj Institute of Pharmacology, Department of Neuropsychopharmacology, Polish Academy of Sciences, Krakow, Poland
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14
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Weber T, Schlotawa L, Dosch R, Hamilton N, Kaiser J, Schiller S, Wenske B, Gärtner J, Henneke M. Zebrafish disease model of human RNASET2-deficient cystic leukoencephalopathy displays abnormalities in early microglia. Biol Open 2020; 9:bio049239. [PMID: 32295832 PMCID: PMC7225086 DOI: 10.1242/bio.049239] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 04/02/2020] [Indexed: 12/14/2022] Open
Abstract
Human infantile-onset RNASET2-deficient cystic leukoencephalopathy is a Mendelian mimic of in utero cytomegalovirus brain infection with prenatally developing inflammatory brain lesions. We used an RNASET2-deficient zebrafish model to elucidate the underlying disease mechanisms. Mutant and wild-type zebrafish larvae brain development between 2 and 5 days post fertilization (dpf) was examined by confocal live imaging in fluorescent reporter lines of the major types of brain cells. In contrast to wild-type brains, RNASET2-deficient larvae displayed increased numbers of microglia with altered morphology, often containing inclusions of neurons. Furthermore, lysosomes within distinct populations of the myeloid cell lineage including microglia showed increased lysosomal staining. Neurons and oligodendrocyte precursor cells remained unaffected. This study provides a first look into the prenatal onset pathomechanisms of human RNASET2-deficient leukoencephalopathy, linking this inborn lysosomal disease to the innate immune system and other immune-related childhood encephalopathies like Aicardi-Goutières syndrome (AGS).
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Affiliation(s)
- Thomas Weber
- Department of Pediatrics and Adolescent Medicine, University Medical Center Goettingen, Robert- Koch- Str. 40, 37075 Goettingen, Germany
| | - Lars Schlotawa
- Department of Pediatrics and Adolescent Medicine, University Medical Center Goettingen, Robert- Koch- Str. 40, 37075 Goettingen, Germany
| | - Roland Dosch
- Department of Human Genetics, University Medical Center Goettingen, Justus-von-Liebig-Weg 11, 37077 Goettingen, Germany
| | - Noémie Hamilton
- The Bateson Centre, University of Sheffield, Firth Court D31, Sheffield S10 2PT, United Kingdom
| | - Jens Kaiser
- Department of Pediatrics and Adolescent Medicine, University Medical Center Goettingen, Robert- Koch- Str. 40, 37075 Goettingen, Germany
| | - Stina Schiller
- Department of Pediatrics and Adolescent Medicine, University Medical Center Goettingen, Robert- Koch- Str. 40, 37075 Goettingen, Germany
| | - Britta Wenske
- Department of Haematology and Oncology, University Medical Center Goettingen, Robert- Koch- Str. 40, 37075 Goettingen, Germany
| | - Jutta Gärtner
- Department of Pediatrics and Adolescent Medicine, University Medical Center Goettingen, Robert- Koch- Str. 40, 37075 Goettingen, Germany
| | - Marco Henneke
- Department of Pediatrics and Adolescent Medicine, University Medical Center Goettingen, Robert- Koch- Str. 40, 37075 Goettingen, Germany
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15
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Hadjikhani N, Albrecht DS, Mainero C, Ichijo E, Ward N, Granziera C, Zürcher NR, Akeju O, Bonnier G, Price J, Hooker JM, Napadow V, Nahrendorf M, Loggia ML, Moskowitz MA. Extra-Axial Inflammatory Signal in Parameninges in Migraine with Visual Aura. Ann Neurol 2020; 87:939-949. [PMID: 32239542 DOI: 10.1002/ana.25731] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/20/2020] [Accepted: 03/22/2020] [Indexed: 01/04/2023]
Abstract
OBJECTIVE Cortical spreading depression (CSD) underlies the neurobiology of migraine with aura (MWA). Animal studies reveal networks of microvessels linking brain-meninges-bone marrow. CSD activates the trigeminovascular system, evoking a meningeal inflammatory response. Accordingly, this study examines the upregulation of an inflammatory marker in extra-axial tissues in migraine with visual aura. METHODS We used simultaneously acquired 11 C-PBR28 positron emission tomography/magnetic resonance imaging data of 18kDa translocator protein (an inflammatory marker) in MWA patients (n = 11) who experienced headaches and visual aura in the preceding month. We measured mean tracer uptake (standardized uptake value ratio [SUVR]) in 4 regions of interest comprising the meninges plus the adjacent overlying skull bone (parameningeal tissues [PMT]). These data were compared to healthy controls and patients with pain (chronic low back pain). RESULTS MWA had significantly higher mean SUVR in PMT overlying occipital cortex than both other groups, although not in the PMT overlying 3 other cortical areas. A positive correlation was also found between the number of visual auras and tracer uptake in occipital PMT. INTERPRETATION A strong persistent extra-axial inflammatory signal was found in meninges and calvarial bone overlying the occipital lobe in migraine with visual auras. Our findings are reminiscent of CSD-induced meningeal inflammation and provide the first imaging evidence implicating inflammation in the pathophysiology of migraine meningeal symptoms. We suspect that this inflammatory focus results from a signal that migrates from underlying brain and if so, may implicate newly discovered bridging vessels that crosstalk between brain and skull marrow, a finding of potential relevance to migraine and other neuroinflammatory brain disorders. ANN NEUROL 2020;87:939-949.
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Affiliation(s)
- Nouchine Hadjikhani
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Daniel S Albrecht
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Caterina Mainero
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Eri Ichijo
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Noreen Ward
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Cristina Granziera
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Nicole R Zürcher
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Oluwaseun Akeju
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Guillaume Bonnier
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Julie Price
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Jacob M Hooker
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Vitaly Napadow
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Matthias Nahrendorf
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Marco L Loggia
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Michael A Moskowitz
- Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
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16
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Zhang X, Wang D, Zhang B, Zhu J, Zhou Z, Cui L. Regulation of microglia by glutamate and its signal pathway in neurodegenerative diseases. Drug Discov Today 2020; 25:1074-1085. [PMID: 32320851 DOI: 10.1016/j.drudis.2020.04.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 03/10/2020] [Accepted: 04/03/2020] [Indexed: 02/06/2023]
Abstract
Microglia are an essential component of the central nervous system (CNS) and are involved in the primary response to microorganisms, neuroinflammation, homeostasis, and tissue regeneration, as well as contributing to the pathogenesis of neurodegenerative diseases. Research has shown that microglial diversity, multifunctionality, and their relationship with glutamate are crucial to determining their roles in these diseases. In this review, we focus on recent progress in determining microglial characteristics and the role of glutamate and its receptors in microglia regulation, which could be a novel therapeutic strategy for neurodegenerative diseases.
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Affiliation(s)
- Xinyue Zhang
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China; Department of Neurobiology, Care Sciences & Society, Division of Neurogeriatrics, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden.
| | - Dan Wang
- Department of Ophthalmology, the First Hospital of Jilin University, Changchun, China.
| | - Bo Zhang
- Department of Neurobiology, Care Sciences & Society, Division of Neurogeriatrics, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden; Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China.
| | - Jie Zhu
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China; Department of Neurobiology, Care Sciences & Society, Division of Neurogeriatrics, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden.
| | - Zhulin Zhou
- Department of Neurobiology, Care Sciences & Society, Division of Neurogeriatrics, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden.
| | - Li Cui
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China.
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An exploratory proton MRS examination of gamma-aminobutyric acid, glutamate, and glutamine and their relationship to affective aspects of chronic pain. Neurosci Res 2020; 163:10-17. [PMID: 32171782 DOI: 10.1016/j.neures.2020.03.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 03/03/2020] [Accepted: 03/10/2020] [Indexed: 01/24/2023]
Abstract
Veterans experience chronic pain more frequently than civilians. Identification of neurobiological mechanisms underlying the pathophysiology of chronic pain in a veteran population may aid in the development of novel treatment targets. In this pilot proof-of-concept study, veterans with chronic pain (N = 61) and no chronic pain (N = 19) completed clinical interviews, self-report questionnaires inquiring about pain history, interference of pain with daily life, and pain catastrophizing, as well as measures of depressive and anxious symptoms. Veterans also underwent single-voxel proton (1H) magnetic resonance spectroscopy (MRS) at 3 T in the anterior cingulate cortex (ACC) using a two-dimensional (2D) J-resolved point spectroscopy sequence. We found no group difference in neurometabolites between veterans with and without chronic pain; however, pain intensity, negative thinking about pain, and description of pain in affective terms were associated with lower GABA/Cre in the ACC. In addition, the Glu/GABA ratio in the ACC was positively associated with anxiety and depressive symptoms in veterans with chronic pain. Reductions in GABA in the ACC may contribute to increased pain intensity and greater pain catastrophizing in veterans with chronic pain. Furthermore, a disturbance in the excitatory-inhibitory balance may contribute to the anxious and depressive symptoms related to chronic pain. Given the pilot nature of the study, these findings must be considered preliminary.
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18
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Lee BJ, Kim JY, Cho HJ, Park D. Sphingosine 1-phosphate receptor modulation attenuate mechanical allodynia in mouse model of chronic complex regional pain syndrome by suppressing pathogenic astrocyte activation. Reg Anesth Pain Med 2020; 45:230-238. [DOI: 10.1136/rapm-2019-100801] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 12/30/2019] [Accepted: 01/04/2020] [Indexed: 11/04/2022]
Abstract
Background and objectivesFTY720 ((2-amino-2-)2-[4-octylphenyl]ethyl)-1,3-propanediol) is an Food and Drug Administration (FDA)-approved immunomodulatory drug for treating multiple sclerosis. It inhibits lymphocyte egression from lymphoid tissues by downregulating sphingosine-1 phosphate receptor (S1PR). To date, there has been no study on the effects of FTY720 on the chronic stage of the complex regional pain syndrome (CRPS) rodent model, despite its antiallodynic effect in previous studies. Thus, the aim of this study is to investigate the effect of FTY720 in a chronic stage of the CRPS mouse model.MethodThe authors used a mouse model of CRPS, involving tibia fracture/cast immobilization, to test the efficacy of intrathecal FTY720 (2.5 or 25 ng daily; 6 days) or vehicle during the chronic (7 weeks after fracture) stage of CRPS.ResultsIntrathecal recombinant FTY720 administration was antiallodynic in the chronic stage of the CRPS mouse model, and such an effect of FTY720 developed by modulating astrocyte activation in the spinal cord. Additionally, according to the in vitro data, the FTY720 treatment inhibited S1P-induced increase in the nitric oxide production and suppression of the NF-κB pathway, by inhibiting the phosphorylation of NF-κB/p65 in astrocytes without toxic effect on astrocytes.ConclusionCollectively, these results demonstrate that intrathecally administered FTY720 attenuates mechanical allodynia in the chronic stage of the CRPS mouse model.
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Subhramanyam CS, Wang C, Hu Q, Dheen ST. Microglia-mediated neuroinflammation in neurodegenerative diseases. Semin Cell Dev Biol 2019; 94:112-120. [PMID: 31077796 DOI: 10.1016/j.semcdb.2019.05.004] [Citation(s) in RCA: 469] [Impact Index Per Article: 93.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 05/07/2019] [Accepted: 05/07/2019] [Indexed: 12/11/2022]
Abstract
Microglia, being the resident immune cells of the central nervous system, play an important role in maintaining tissue homeostasis and contributes towards brain development under normal conditions. However, when there is a neuronal injury or other insult, depending on the type and magnitude of stimuli, microglia will be activated to secrete either proinflammatory factors that enhance cytotoxicity or anti-inflammatory neuroprotective factors that assist in wound healing and tissue repair. Excessive microglial activation damages the surrounding healthy neural tissue, and the factors secreted by the dead or dying neurons in turn exacerbate the chronic activation of microglia, causing progressive loss of neurons. It is the case observed in many neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease and amyotrophic lateral sclerosis. This review gives a detailed account of the microglia-mediated neuroinflammation in various neurodegenerative diseases. Hence, resolving chronic inflammation mediated by microglia bears great promise as a novel treatment strategy to reduce neuronal damage and to foster a permissive environment for further regeneration effort.
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Affiliation(s)
| | - Cheng Wang
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, 4 Medical Drive, 117594, Singapore
| | - Qidong Hu
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, 4 Medical Drive, 117594, Singapore.
| | - S Thameem Dheen
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, 4 Medical Drive, 117594, Singapore.
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20
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Cespuglio R, Amrouni D, Raymond EF, Bouteille B, Buguet A. Cerebral inducible nitric oxide synthase protein expression in microglia, astrocytes and neurons in Trypanosoma brucei brucei-infected rats. PLoS One 2019; 14:e0215070. [PMID: 30995270 PMCID: PMC6469759 DOI: 10.1371/journal.pone.0215070] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 03/26/2019] [Indexed: 11/18/2022] Open
Abstract
To study the anatomo-biochemical substrates of brain inflammatory processes, Wistar male rats were infected with Trypanosoma brucei brucei. With this reproducible animal model of human African trypanosomiasis, brain cells (astrocytes, microglial cells, neurons) expressing the inducible nitric oxide synthase (iNOS) enzyme were revealed. Immunohistochemistry was achieved for each control and infected animal through eight coronal brain sections taken along the caudorostral axis of the brain (brainstem, cerebellum, diencephalon and telencephalon). Specific markers of astrocytes (anti-glial fibrillary acidic protein), microglial cells (anti-integrin alpha M) or neurons (anti-Neuronal Nuclei) were employed. The iNOS staining was present in neurons, astrocytes and microglial cells, but not in oligodendrocytes. Stained astrocytes and microglial cells resided mainly near the third cavity in the rostral part of brainstem (periaqueductal gray), diencephalon (thalamus and hypothalamus) and basal telencephalon. Stained neurons were scarce in basal telencephalon, contrasting with numerous iNOS-positive neuroglial cells. Contrarily, in dorsal telencephalon (neocortex and hippocampus), iNOS-positive neurons were plentiful, contrasting with the marked paucity of labelled neuroglial (astrocytes and microglial) cells. The dual distribution between iNOS-labelled neuroglial cells and iNOS-labelled neurons is a feature that has never been described before. Functionalities attached to such a divergent distribution are discussed.
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Affiliation(s)
- Raymond Cespuglio
- Neuroscience Research Centre of Lyon (CRNL), Neurochem, Faculty of Medicine, Claude-Bernard Lyon-1 University, Lyon, France
- Sechenov 1st Moscow State Medical University, Laboratory of Psychiatric Neurobiology, Moscow, Russia
| | - Donia Amrouni
- Neuroscience Research Centre of Lyon (CRNL), Neurochem, Faculty of Medicine, Claude-Bernard Lyon-1 University, Lyon, France
| | - Elizabeth F. Raymond
- Faculty of Medicine, team EA 4171, Claude-Bernard Lyon-1 University, Lyon, France
| | - Bernard Bouteille
- Department of Parasitology, Dupuytren University Hospital, Limoges, France
| | - Alain Buguet
- Malaria Research Unit, UMR 5246 CNRS, Claude-Bernard Lyon-1 University, Villeurbanne, France
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21
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Nack A, Brendel M, Nedelcu J, Daerr M, Nyamoya S, Beyer C, Focke C, Deussing M, Hoornaert C, Ponsaerts P, Schmitz C, Bartenstein P, Rominger A, Kipp M. Expression of Translocator Protein and [18F]-GE180 Ligand Uptake in Multiple Sclerosis Animal Models. Cells 2019; 8:cells8020094. [PMID: 30696113 PMCID: PMC6406715 DOI: 10.3390/cells8020094] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 01/16/2019] [Accepted: 01/23/2019] [Indexed: 12/19/2022] Open
Abstract
Positron emission tomography (PET) ligands targeting the translocator protein (TSPO) represent promising tools to visualize neuroinflammation in multiple sclerosis (MS). Although it is known that TSPO is expressed in the outer mitochondria membrane, its cellular localization in the central nervous system under physiological and pathological conditions is not entirely clear. The purpose of this study was to assess the feasibility of utilizing PET imaging with the TSPO tracer, [18F]-GE180, to detect histopathological changes during experimental demyelination, and to determine which cell types express TSPO. C57BL/6 mice were fed with cuprizone for up to 5 weeks to induce demyelination. Groups of mice were investigated by [18F]-GE180 PET imaging at week 5. Recruitment of peripheral immune cells was triggered by combining cuprizone intoxication with MOG35–55 immunization (i.e., Cup/EAE). Immunofluorescence double-labelling and transgene mice were used to determine which cell types express TSPO. [18F]-GE180-PET reliably detected the cuprizone-induced pathology in various white and grey matter regions, including the corpus callosum, cortex, hippocampus, thalamus and caudoputamen. Cuprizone-induced demyelination was paralleled by an increase in TSPO expression, glia activation and axonal injury. Most of the microglia and around one-third of the astrocytes expressed TSPO. TSPO expression induction was more severe in the white matter corpus callosum compared to the grey matter cortex. Although mitochondria accumulate at sites of focal axonal injury, these mitochondria do not express TSPO. In Cup/EAE mice, both microglia and recruited monocytes contribute to the TSPO expressing cell populations. These findings support the notion that TSPO is a valuable marker for the in vivo visualization and quantification of neuropathological changes in the MS brain. The pathological substrate of an increase in TSPO-ligand binding might be diverse including microglia activation, peripheral monocyte recruitment, or astrocytosis, but not axonal injury.
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MESH Headings
- Animals
- Astrocytes/pathology
- Astrocytes/ultrastructure
- Axons/metabolism
- Axons/ultrastructure
- Biomarkers/metabolism
- Carbazoles/metabolism
- Cuprizone
- Demyelinating Diseases/diagnostic imaging
- Demyelinating Diseases/pathology
- Disease Models, Animal
- Encephalomyelitis, Autoimmune, Experimental/diagnostic imaging
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Female
- Inflammation/pathology
- Ligands
- Mice, Inbred C57BL
- Mitochondria/metabolism
- Mitochondria/ultrastructure
- Monocytes/metabolism
- Multiple Sclerosis/diagnostic imaging
- Neuroglia/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, GABA/genetics
- Receptors, GABA/metabolism
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Affiliation(s)
- Anne Nack
- Department of Anatomy II, Ludwig-Maximilians-University of Munich, 80336 Munich, Germany.
- Department of Anatomy, 39071 Rostock University Medical Center, Rostock, Germany.
| | - Matthias Brendel
- Department of Nuclear Medicine, University Hospital, LMU Munich, 80336 Munich, Germany.
| | - Julia Nedelcu
- Department of Anatomy II, Ludwig-Maximilians-University of Munich, 80336 Munich, Germany.
- Department of Anatomy, 39071 Rostock University Medical Center, Rostock, Germany.
| | - Markus Daerr
- Department of Anatomy II, Ludwig-Maximilians-University of Munich, 80336 Munich, Germany.
- Department of Anatomy, 39071 Rostock University Medical Center, Rostock, Germany.
| | - Stella Nyamoya
- Department of Anatomy II, Ludwig-Maximilians-University of Munich, 80336 Munich, Germany.
- Institute of Neuroanatomy, RWTH Aachen University, 52074 Aachen, Germany.
- Department of Anatomy, 39071 Rostock University Medical Center, Rostock, Germany.
| | - Cordian Beyer
- Institute of Neuroanatomy, RWTH Aachen University, 52074 Aachen, Germany.
| | - Carola Focke
- Department of Nuclear Medicine, University Hospital, LMU Munich, 80336 Munich, Germany.
| | - Maximilian Deussing
- Department of Nuclear Medicine, University Hospital, LMU Munich, 80336 Munich, Germany.
| | - Chloé Hoornaert
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium.
- Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium.
| | - Peter Ponsaerts
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium.
- Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium.
| | - Christoph Schmitz
- Department of Anatomy II, Ludwig-Maximilians-University of Munich, 80336 Munich, Germany.
| | - Peter Bartenstein
- Department of Nuclear Medicine, University Hospital, LMU Munich, 80336 Munich, Germany.
| | - Axel Rominger
- Department of Nuclear Medicine, University Hospital, LMU Munich, 80336 Munich, Germany.
- Department of Nuclear Medicine, Inselspital, University Hospital Bern, Bern, Switzerland.
| | - Markus Kipp
- Department of Anatomy, 39071 Rostock University Medical Center, Rostock, Germany.
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22
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Jung YH, Kim H, Lee D, Lee JY, Lee WJ, Moon JY, Kim YC, Choi SH, Kang DH. Disruption of Homeostasis Based on the Right and Left Hemisphere in Patients with Complex Regional Pain Syndrome. Neuroimmunomodulation 2019; 26:276-284. [PMID: 31865325 DOI: 10.1159/000504140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/14/2019] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Although the clinical features and pathophysiology of complex regional pain syndrome (CRPS) have been studied in the peripheral and central nervous systems, few plausible pathological interactions are known among the metabolites in these systems. Thus, the purpose of this study was to investigate abnormal relationships and interactions between peripheral metabolites and central neurometabolites in patients with CRPS. METHODS Various metabolites and molecules were measured in the peripheral blood, and central neurometabolites in the right and left thalamus using proton magnetic resonance spectroscopy in 12 patients with CRPS and 11 healthy controls. Interactions between peripheral metabolites in blood and central neurometabolites in the right and left thalamus were also investigated. RESULTS The interactions between peripheral and central metabolites were different in the right and left hemispheres of healthy subjects, suggesting the presence of right hemisphere-dependent energy homeostasis and left hemisphere-dependent acid-base homeostasis that enables effective functioning. The interactions between central and peripheral metabolites in CRPS patients were distinct from those in healthy individuals, supporting the possibility of abnormal interactions and disrupted homeostasis between peripheral and central metabolites, which may result from neuroinflammation and immune system dysfunction. CONCLUSION To the authors' knowledge, this is the first report describing abnormal metabolic dysfunction and disrupted homeostasis in interactions between metabolites of the peripheral and central nervous systems in CRPS. The approach used to uncover hidden pathophysiologies will improve understanding of how chronic pain can disrupt homeostasis in interactions between two systems and how alternative metabolites can be activated to recover and compensate for pathological dysfunctions in patients with CRPS.
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Affiliation(s)
- Ye-Ha Jung
- Department of Psychiatry, Seoul National University Hospital, Seoul, Republic of Korea
| | - Hyeonjin Kim
- Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea
| | - Dasom Lee
- Department of Psychiatry, Seoul National University Hospital, Seoul, Republic of Korea
- Emotional Information and Communication Technology Association, Seoul, Republic of Korea
| | - Jae-Yeon Lee
- Department of Psychiatry, Seoul National University Hospital, Seoul, Republic of Korea
| | - Won Joon Lee
- Department of Psychiatry, Kangdong Sacred Heart Hospital, Seoul, Republic of Korea
| | - Jee Youn Moon
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Republic of Korea
| | - Yong Chul Kim
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Republic of Korea
| | - Soo-Hee Choi
- Department of Psychiatry, Seoul National University Hospital, Seoul, Republic of Korea
- Department of Psychiatry, Seoul National University College of Medicine and Institute of Human Behavioral Medicine, SNU-MRC, Seoul, Republic of Korea
| | - Do-Hyung Kang
- Emotional Information and Communication Technology Association, Seoul, Republic of Korea,
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Chagas LDS, Trindade P, Gomes ALT, Mendonça HR, Campello-Costa P, Faria Melibeu ADC, Linden R, Serfaty CA. Rapid plasticity of intact axons following a lesion to the visual pathways during early brain development is triggered by microglial activation. Exp Neurol 2018; 311:148-161. [PMID: 30312606 DOI: 10.1016/j.expneurol.2018.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 08/21/2018] [Accepted: 10/08/2018] [Indexed: 12/11/2022]
Abstract
Lesions in the central nervous system (CNS) can often induce structural reorganization within intact circuits of the brain. Several studies show advances in the understanding of mechanisms of brain plasticity and the role of the immune system activation. Microglia, a myeloid derived cell population colonizes the CNS during early phases of embryonic development. In the present study, we evaluated the role of microglial activation in the sprouting of intact axons following lesions of the visual pathways. We evaluated the temporal course of microglial activation in the superior colliculus following a contralateral monocular enucleation (ME) and the possible involvement of microglial cells in the plastic reorganization of the intact, uncrossed, retinotectal pathway from the remaining eye. Lister Hooded rats were enucleated at PND 10 and submitted to systemic treatment with inhibitors of microglial activation: cyclosporine A and minocycline. The use of neuroanatomical tracers allowed us to evaluate the time course of structural axonal plasticity. Immunofluorescence and western blot techniques were used to observe the expression of microglial marker, Iba-1 and the morphology of microglial cells. Following a ME, Iba-1 immunoreactivity showed a progressive increase of microglial activation in the contralateral SC at 24 h, peaking at 72 h after the lesion. Treatment with inhibitors of microglial activation blocked both the structural plasticity of intact uncrossed retinotectal axons and microglial activation as seen by the decrease of Iba-1 immunoreactivity. The local blockade of TNF-α with a neutralizing antibody was also able to block axonal plasticity of the intact eye following a ME. The data support the hypothesis that microglial activation is a necessary step for the regulation of neuroplasticity induced by lesions during early brain development.
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Affiliation(s)
- Luana da Silva Chagas
- Federal Fluminense University, Biology Institute, Neurobiology Department, Laboratory of Neural Plasticity - Niteroi, PO Box: 100180, Brazil
| | - Pablo Trindade
- D'Or Institute for Research and Education (IDOR), Rio de Janeiro, Brazil; Post Graduating Program in Molecular and Cellular Biology, Federal University of the State of Rio de Janeiro, Brazil
| | - Ana Lúcia Tavares Gomes
- Federal Fluminense University, Biology Institute, Neurobiology Department, Laboratory of Neural Plasticity - Niteroi, PO Box: 100180, Brazil
| | | | - Paula Campello-Costa
- Federal Fluminense University, Biology Institute, Neurobiology Department, Laboratory of Neural Plasticity - Niteroi, PO Box: 100180, Brazil
| | - Adriana da Cunha Faria Melibeu
- Federal Fluminense University, Biology Institute, Neurobiology Department, Laboratory of Neural Plasticity - Niteroi, PO Box: 100180, Brazil
| | - Rafael Linden
- Federal University of Rio de Janeiro, Biophisics Institute, Brazil
| | - Claudio Alberto Serfaty
- Federal Fluminense University, Biology Institute, Neurobiology Department, Laboratory of Neural Plasticity - Niteroi, PO Box: 100180, Brazil; National Institute for Science and Technology in Neuroimmunomodulation - INCT/NIM, Brazil.
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24
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Zhang X, Yin Q, Berridge M, Wang C. Application of molecular imaging technology in neurotoxicology research. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, ENVIRONMENTAL CARCINOGENESIS & ECOTOXICOLOGY REVIEWS 2018; 36:113-124. [PMID: 30199343 DOI: 10.1080/10590501.2018.1492200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Molecular imaging has been widely applied in preclinical research. Among these new molecular imaging modalities, microPET imaging can be utilized as a very powerful tool that can obtain the measurements of multiple biological processes in various organs repeatedly in a same subject. This review discusses how this new approach provides noninvasive biomarker for neurotoxicology research and summarizes microPET findings with multiple radiotracers on the variety of neurotoxicity induced by toxic agents in both the rodent and the nonhuman primate brain.
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Affiliation(s)
- Xuan Zhang
- a Division of Neurotoxicology , U.S. Food and Drug Administration, National Center for Toxicological Research , Jefferson , Arkansas , USA
| | - Qi Yin
- a Division of Neurotoxicology , U.S. Food and Drug Administration, National Center for Toxicological Research , Jefferson , Arkansas , USA
| | - Marc Berridge
- b 3D Imaging, LLC, University of Arkansas for Medical Sciences , Little Rock , Arkansas , USA
| | - Che Wang
- a Division of Neurotoxicology , U.S. Food and Drug Administration, National Center for Toxicological Research , Jefferson , Arkansas , USA
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25
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Kim JH, Park JS, Park D. Anti-allodynic effect of interleukin 10 in a mouse model of complex regional pain syndrome through reduction of NK1 receptor expression of microglia in the spinal cord. J Pain Res 2018; 11:1729-1741. [PMID: 30233230 PMCID: PMC6129024 DOI: 10.2147/jpr.s166624] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background To date, there has been no study on the effects of interleukin-10 (IL-10) on complex regional pain syndrome (CRPS) rodent models, despite the anti-allodynic effect of IL-10 in previous studies. Thus, the aim of this study was to investigate the effect of IL-10 in a CRPS mouse model and find whether early inhibition of neuro-inflammation by IL-10 administration, which is considered to be one of the important mechanisms in the generation of central sensitization, could prevent the transition from the acute stage to the chronic stage of CRPS. Method A mouse model of CRPS (n=6/group) involving tibia fracture/cast immobilization to test the efficacy of intrathecal IL-10 (0.3 μg/5 μL-1 day-1 for 7 days) or vehicle during the acute (3 weeks after fracture) stage of CRPS. Results Intrathecal recombinant IL-10 (rIL-10) administration was anti-allodynic in the acute stage of the CRPS mouse model, and these anti-allodynic effects of IL-10 developed by modulating microglial activation and decreasing NK1 receptor expression in the spinal cord. However, intrathecal rIL-10 administration in the acute stage of the CRPS mouse model cannot prevent the transition to the chronic stage of CRPS in the acute stage of CRPS. Conclusion Collectively, these results demonstrate that intrathecally administered rIL-10 attenuates mechanical allodynia in the CRPS mouse model. However, this effect of IL-10 on allodynia in the acute stage of CRPS was not sufficient to prevent the transition to the chronic stage of CRPS. In the future, further studies about the mechanisms of central sensitization in CRPS will be necessary.
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Affiliation(s)
- Jong-Heon Kim
- Department of Pharmacology, Brain Science and Engineering Institute, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Jin-Sung Park
- Department of Neurology, School of Medicine, Kyungpook National University Chilgok Hospital, Daegu, Republic of Korea
| | - Donghwi Park
- Department of Rehabilitation Medicine, Daegu Fatima Hospital, Daegu, Republic of Korea, .,Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu, Republic of Korea,
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26
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Guo C, Qu X, Rangaswamy N, Leehy B, Xiang C, Rice D, Prasanna G. A murine glaucoma model induced by rapid in vivo photopolymerization of hyaluronic acid glycidyl methacrylate. PLoS One 2018; 13:e0196529. [PMID: 29949582 PMCID: PMC6021085 DOI: 10.1371/journal.pone.0196529] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 04/13/2018] [Indexed: 12/04/2022] Open
Abstract
Glaucoma is an optic neuropathy commonly associated with elevated intraocular pressure (IOP) resulting in progressive loss of retinal ganglion cells (RGCs) and optic nerve degeneration, leading to blindness. New therapeutic approaches that better preserve the visual field by promoting survival and health of RGCs are highly needed since RGC death occurs despite good IOP control in glaucoma patients. We have developed a novel approach to reliably induce chronic IOP elevation in mouse using a photopolymerizable biomatrix, hyaluronic acid glycidyl methacrylate. This is achieved by rapid in vivo crosslinking of the biomatrix at the iridocorneal angle by a flash of ultraviolet A (UVA) light to impede the aqueous outflow pathway with a controllable manner. Sustained IOP elevation was induced after a single manipulation and was maintained at ~45% above baseline for >4 weeks. Significant thinning of the inner retina and ~35% reduction in RGCs and axons was noted within one month of IOP elevation. Optic nerve degeneration showed positive correlation with cumulative IOP elevation. Activation of astrocytes and microglia appeared to be an early event in response to IOP elevation preceding detectable RGC and axon loss. Attenuated glial reactivity was noted at later stage where significant RGC/axon loss had occurred suggesting astrocytes and microglia may play different roles over the course of glaucomatous degeneration. This novel murine glaucoma model is reproducible and displays cellular changes that recapitulate several pathophysiological features of glaucoma.
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Affiliation(s)
- Chenying Guo
- Department of Ophthalmology, Novartis Institutes for BioMedical Research, Cambridge, MA, United States of America
- * E-mail: (GP); (CG)
| | - Xin Qu
- Department of Ophthalmology, Novartis Institutes for BioMedical Research, Cambridge, MA, United States of America
| | - Nalini Rangaswamy
- Department of Ophthalmology, Novartis Institutes for BioMedical Research, Cambridge, MA, United States of America
| | - Barrett Leehy
- Department of Ophthalmology, Novartis Institutes for BioMedical Research, Cambridge, MA, United States of America
| | - Chuanxi Xiang
- Department of Ophthalmology, Novartis Institutes for BioMedical Research, Cambridge, MA, United States of America
| | - Dennis Rice
- Department of Ophthalmology, Novartis Institutes for BioMedical Research, Cambridge, MA, United States of America
| | - Ganesh Prasanna
- Department of Ophthalmology, Novartis Institutes for BioMedical Research, Cambridge, MA, United States of America
- * E-mail: (GP); (CG)
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27
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Liu GJ, Middleton RJ, Kam WWY, Chin DY, Hatty CR, Chan RHY, Banati RB. Functional gains in energy and cell metabolism after TSPO gene insertion. Cell Cycle 2017; 16:436-447. [PMID: 28103132 PMCID: PMC5351937 DOI: 10.1080/15384101.2017.1281477] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Recent loss-of-function studies in tissue-specific as well as global Tspo (Translocator Protein 18 kDa) knockout mice have not confirmed its long assumed indispensability for the translocation of cholesterol across the mitochondrial inter-membrane space, a rate-limiting step in steroid biosynthesis. Instead, recent studies in global Tspo knockout mice indicate that TSPO may play a more fundamental role in cellular bioenergetics, which may include the indirect down-stream regulation of transport or metabolic functions. To examine whether overexpression of the TSPO protein alters the cellular bioenergetic profile, Jurkat cells with low to absent endogenous expression were transfected with a TSPO construct to create a stable cell line with de novo expression of exogenous TSPO protein. Expression of TSPO was confirmed by RT-qPCR, radioligand binding with [3H]PK11195 and immunocytochemistry with a TSPO antibody. We demonstrate that TSPO gene insertion causes increased transcription of genes involved in the mitochondrial electron transport chain. Furthermore, TSPO insertion increased mitochondrial ATP production as well as cell excitability, reflected in a decrease in patch clamp recorded rectified K channel currents. These functional changes were accompanied by an increase in cell proliferation and motility, which were inhibited by PK11195, a selective ligand for TSPO. We suggest that TSPO may serve a range of functions that can be viewed as downstream regulatory effects of its primary, evolutionary conserved role in cell metabolism and energy production.
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Affiliation(s)
- Guo-Jun Liu
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,b Faculty of Health Science and Brain and Mind Centre, University of Sydney , NSW , Australia
| | - Ryan J Middleton
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia
| | - Winnie Wai-Ying Kam
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,c Department of Health Technology and Informatics , Hong Kong Polytechnic University , Hung Hom, Hong Kong , China
| | - David Y Chin
- d NCRIS Biologics Facility, Australian Institute for Bioengineering and Nanotechnology, University of Queensland , QLD , Australia
| | - Claire R Hatty
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,b Faculty of Health Science and Brain and Mind Centre, University of Sydney , NSW , Australia
| | - Ronald H Y Chan
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,b Faculty of Health Science and Brain and Mind Centre, University of Sydney , NSW , Australia
| | - Richard B Banati
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,b Faculty of Health Science and Brain and Mind Centre, University of Sydney , NSW , Australia
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28
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Garcia-Mesa Y, Jay TR, Checkley MA, Luttge B, Dobrowolski C, Valadkhan S, Landreth GE, Karn J, Alvarez-Carbonell D. Immortalization of primary microglia: a new platform to study HIV regulation in the central nervous system. J Neurovirol 2016; 23:47-66. [PMID: 27873219 PMCID: PMC5329090 DOI: 10.1007/s13365-016-0499-3] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 11/03/2016] [Accepted: 11/09/2016] [Indexed: 12/17/2022]
Abstract
The major reservoirs for HIV in the CNS are in the microglia, perivascular macrophages, and to a lesser extent, astrocytes. To study the molecular events controlling HIV expression in the microglia, we developed a reliable and robust method to immortalize microglial cells from primary glia from fresh CNS tissues and commercially available frozen glial cells. Primary human cells, including cells obtained from adult brain tissue, were transformed with lentiviral vectors expressing SV40 T antigen or a combination of SVR40 T antigen and hTERT. The immortalized cells have microglia-like morphology and express key microglial surface markers including CD11b, TGFβR, and P2RY12. Importantly, these cells were confirmed to be of human origin by sequencing. The RNA expression profiles identified by RNA-seq are also characteristic of microglial cells. Furthermore, the cells demonstrate the expected migratory and phagocytic activity, and the capacity to mount an inflammatory response characteristic of primary microglia. The immortalization method has also been successfully applied to a wide range of microglia from other species (macaque, rat, and mouse). To investigate different aspects of HIV molecular regulation in CNS, the cells have been superinfected with HIV reporter viruses and latently infected clones have been selected that reactive HIV in response to inflammatory signals. The cell lines we have developed and rigorously characterized will provide an invaluable resource for the study of HIV infection in microglial cells as well as studies of microglial cell function.
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Affiliation(s)
- Yoelvis Garcia-Mesa
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH 44106 USA
| | - Taylor R. Jay
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106 USA
| | - Mary Ann Checkley
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH 44106 USA
| | - Benjamin Luttge
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH 44106 USA
| | - Curtis Dobrowolski
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH 44106 USA
| | - Saba Valadkhan
- Department of Biochemistry, Case Western Reserve University, Cleveland, OH 44106 USA
| | - Gary E. Landreth
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106 USA
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH 44106 USA
| | - David Alvarez-Carbonell
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH 44106 USA
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Zhang X, Liu F, Slikker W, Wang C, Paule MG. Minimally invasive biomarkers of general anesthetic-induced developmental neurotoxicity. Neurotoxicol Teratol 2016; 60:95-101. [PMID: 27784630 DOI: 10.1016/j.ntt.2016.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/29/2016] [Accepted: 10/21/2016] [Indexed: 12/22/2022]
Abstract
The association of general anesthesia with developmental neurotoxicity, while nearly impossible to study in pediatric populations, is clearly demonstrable in a variety of animal models from rodents to nonhuman primates. Nearly all general anesthetics tested have been shown to cause abnormal brain cell death in animals when administered during periods of rapid brain growth. The ability to repeatedly assess in the same subjects adverse effects induced by general anesthetics provides significant power to address the time course of important events associated with exposures. Minimally-invasive procedures provide the opportunity to bridge the preclinical/clinical gap by providing the means to more easily translate findings from the animal laboratory to the human clinic. Positron Emission Tomography or PET is a tool with great promise for realizing this goal. PET for small animals (microPET) is providing valuable data on the life cycle of general anesthetic induced neurotoxicity. PET radioligands (annexin V and DFNSH) targeting apoptotic processes have demonstrated that a single bout of general anesthesia effected during a vulnerable period of CNS development can result in prolonged apoptotic signals lasting for several weeks in the rat. A marker of cellular proliferation (FLT) has demonstrated in rodents that general anesthesia-induced inhibition of neural progenitor cell proliferation is evident when assessed a full 2weeks after exposure. Activated glia express Translocator Protein (TSPO) which can be used as a marker of presumed neuroinflammatory processes and a PET ligand for the TSPO (FEPPA) has been used to track this process in both rat and nonhuman primate models. It has been shown that single bouts of general anesthesia can result in elevated TSPO expression lasting for over a week. These examples demonstrate the utility of specific PET tracers to inform, in a minimally-invasive fashion, processes associated with general anesthesia-induced developmental neurotoxicity. The fact that PET procedures are also used clinically suggests an opportunity to confirm in humans what has been repeatedly observed in animals.
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Betlazar C, Middleton RJ, Banati RB, Liu GJ. The impact of high and low dose ionising radiation on the central nervous system. Redox Biol 2016; 9:144-156. [PMID: 27544883 PMCID: PMC4993858 DOI: 10.1016/j.redox.2016.08.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 08/06/2016] [Accepted: 08/09/2016] [Indexed: 12/12/2022] Open
Abstract
Responses of the central nervous system (CNS) to stressors and injuries, such as ionising radiation, are modulated by the concomitant responses of the brains innate immune effector cells, microglia. Exposure to high doses of ionising radiation in brain tissue leads to the expression and release of biochemical mediators of ‘neuroinflammation’, such as pro-inflammatory cytokines and reactive oxygen species (ROS), leading to tissue destruction. Contrastingly, low dose ionising radiation may reduce vulnerability to subsequent exposure of ionising radiation, largely through the stimulation of adaptive responses, such as antioxidant defences. These disparate responses may be reflective of non-linear differential microglial activation at low and high doses, manifesting as an anti-inflammatory or pro-inflammatory functional state. Biomarkers of pathology in the brain, such as the mitochondrial Translocator Protein 18 kDa (TSPO), have facilitated in vivo characterisation of microglial activation and ‘neuroinflammation’ in many pathological states of the CNS, though the exact function of TSPO in these responses remains elusive. Based on the known responsiveness of TSPO expression to a wide range of noxious stimuli, we discuss TSPO as a potential biomarker of radiation-induced effects. Ionising radiation can modulate responses of microglial cells in the CNS. High doses can induce ROS formation, oxidative stress and neuroinflammation. Low doses can mitigate tissue damage via antioxidant defences. TSPO as a potential biomarker and modulator of radiation induced effects in the CNS. Non-linear differential microglial activation to high and low doses is proposed.
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Affiliation(s)
- Calina Betlazar
- Bioanalytics group, Life Sciences, Australian Nuclear Science and Technology Organisation (ANSTO), New Illawarra Road, Lucas Heights, NSW 2234, Australia; Discipline of Medical Imaging & Radiation Sciences, Faculty of Health Sciences, The University of Sydney, 75 East Street, Lidcombe, NSW 2141, Australia
| | - Ryan J Middleton
- Bioanalytics group, Life Sciences, Australian Nuclear Science and Technology Organisation (ANSTO), New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Richard B Banati
- Bioanalytics group, Life Sciences, Australian Nuclear Science and Technology Organisation (ANSTO), New Illawarra Road, Lucas Heights, NSW 2234, Australia; Discipline of Medical Imaging & Radiation Sciences, Faculty of Health Sciences, The University of Sydney, 75 East Street, Lidcombe, NSW 2141, Australia.
| | - Guo-Jun Liu
- Bioanalytics group, Life Sciences, Australian Nuclear Science and Technology Organisation (ANSTO), New Illawarra Road, Lucas Heights, NSW 2234, Australia; Discipline of Medical Imaging & Radiation Sciences, Faculty of Health Sciences, The University of Sydney, 75 East Street, Lidcombe, NSW 2141, Australia.
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In Vivo Monitoring of Sevoflurane-induced Adverse Effects in Neonatal Nonhuman Primates Using Small-animal Positron Emission Tomography. Anesthesiology 2016; 125:133-46. [DOI: 10.1097/aln.0000000000001154] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Abstract
Background
Animals exposed to sevoflurane during development sustain neuronal cell death in their developing brains. In vivo micro-positron emission tomography (PET)/computed tomography imaging has been utilized as a minimally invasive method to detect anesthetic-induced neuronal adverse effects in animal studies.
Methods
Neonatal rhesus monkeys (postnatal day 5 or 6, 3 to 6 per group) were exposed for 8 h to 2.5% sevoflurane with or without acetyl-l-carnitine (ALC). Control monkeys were exposed to room air with or without ALC. Physiologic status was monitored throughout exposures. Depth of anesthesia was monitored using quantitative electroencephalography. After the exposure, microPET/computed tomography scans using 18F-labeled fluoroethoxybenzyl-N-(4-phenoxypyridin-3-yl) acetamide (FEPPA) were performed repeatedly on day 1, 1 and 3 weeks, and 2 and 6 months after exposure.
Results
Critical physiologic metrics in neonatal monkeys remained within the normal range during anesthetic exposures. The uptake of [18F]-FEPPA in the frontal and temporal lobes was increased significantly 1 day or 1 week after exposure, respectively. Analyses of microPET images recorded 1 day after exposure showed that sevoflurane exposure increased [18F]-FEPPA uptake in the frontal lobe from 0.927 ± 0.04 to 1.146 ± 0.04, and in the temporal lobe from 0.859 ± 0.05 to 1.046 ± 0.04 (mean ± SE, P < 0.05). Coadministration of ALC effectively blocked the increase in FEPPA uptake. Sevoflurane-induced adverse effects were confirmed by histopathologic evidence as well.
Conclusions
Sevoflurane-induced general anesthesia during development increases glial activation, which may serve as a surrogate for neurotoxicity in the nonhuman primate brain. ALC is a potential protective agent against some of the adverse effects associated with such exposures.
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Abstract
UNLABELLED Treating pain is one of the most difficult challenges in medicine and a key facet of disease management. The isolation of morphine by Friedrich Sertürner in 1804 added an essential pharmacological tool in the treatment of pain and spawned the discovery of a new class of drugs known collectively as opioid analgesics. Revered for their potent pain-relieving effects, even Morpheus the god of dreams could not have dreamt that his opium tincture would be both a gift and a burden to humankind. To date, morphine and other opioids remain essential analgesics for alleviating pain. However, their use is plagued by major side effects, such as analgesic tolerance (diminished pain-relieving effects), hyperalgesia (increased pain sensitivity), and drug dependence. This review highlights recent advances in understanding the key causes of these adverse effects and explores the effect of chronic pain on opioid reward. SIGNIFICANCE STATEMENT Chronic pain is pervasive and afflicts >100 million Americans. Treating pain in these individuals is notoriously difficult and often requires opioids, one of the most powerful and effective classes of drugs used for controlling pain. However, their use is plagued by major side effects, such as a loss of pain-relieving effects (analgesic tolerance), paradoxical pain (hyperalgesia), and addiction. Despite the potential side effects, opioids remain the pharmacological cornerstone of modern pain therapy. This review highlights recent breakthroughs in understanding the key causes of these adverse effects and explores the cellular control of opioid systems in reward and aversion. The findings will challenge traditional views of the good, the bad, and the ugly of opioids.
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Ejaz S, Emmrich JV, Sitnikov SL, Hong YT, Sawiak SJ, Fryer TD, Aigbirhio FI, Williamson DJ, Baron JC. Normobaric hyperoxia markedly reduces brain damage and sensorimotor deficits following brief focal ischaemia. Brain 2016; 139:751-64. [PMID: 26767570 DOI: 10.1093/brain/awv391] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 11/16/2015] [Indexed: 01/02/2023] Open
Abstract
'True' transient ischaemic attacks are characterized not only clinically, but also radiologically by a lack of corresponding changes on magnetic resonance imaging. During a transient ischaemic attack it is assumed that the affected tissue is penumbral but rescued by early spontaneous reperfusion. There is, however, evidence from rodent studies that even brief focal ischaemia not resulting in tissue infarction can cause extensive selective neuronal loss associated with long-lasting sensorimotor impairment but normal magnetic resonance imaging. Selective neuronal loss might therefore contribute to the increasingly recognized cognitive impairment occurring in patients with transient ischaemic attacks. It is therefore relevant to consider treatments to reduce brain damage occurring with transient ischaemic attacks. As penumbral neurons are threatened by markedly constrained oxygen delivery, improving the latter by increasing arterial O2 content would seem logical. Despite only small increases in arterial O2 content, normobaric oxygen therapy experimentally induces significant increases in penumbral O2 pressure and by such may maintain the penumbra alive until reperfusion. Nevertheless, the effects of normobaric oxygen therapy on infarct volume in rodent models have been conflicting, although duration of occlusion appeared an important factor. Likewise, in the single randomized trial published to date, early-administered normobaric oxygen therapy had no significant effect on clinical outcome despite reduced diffusion-weighted imaging lesion growth during therapy. Here we tested the hypothesis that normobaric oxygen therapy prevents both selective neuronal loss and sensorimotor deficits in a rodent model mimicking true transient ischaemic attack. Normobaric oxygen therapy was applied from the onset and until completion of 15 min distal middle cerebral artery occlusion in spontaneously hypertensive rats, a strain representative of the transient ischaemic attack-prone population. Whereas normoxic controls showed normal magnetic resonance imaging but extensive cortical selective neuronal loss associated with microglial activation (present both at Day 14 in vivo and at Day 28 post-mortem) and marked and long-lasting sensorimotor deficits, normobaric oxygen therapy completely prevented sensorimotor deficit (P < 0.02) and near-completely Day 28 selective neuronal loss (P < 0.005). Microglial activation was substantially reduced at Day 14 and completely prevented at Day 28 (P = 0.002). Our findings document that normobaric oxygen therapy administered during ischaemia nearly completely prevents the neuronal death, microglial inflammation and sensorimotor impairment that characterize this rodent true transient ischaemic attack model. Taken together with the available literature, normobaric oxygen therapy appears a promising therapy for short-lasting ischaemia, and is attractive clinically as it could be started at home in at-risk patients or in the ambulance in subjects suspected of transient ischaemic attack/early stroke. It may also be a straightforward adjunct to reperfusion therapies, and help prevent subtle brain damage potentially contributing to long-term cognitive and sensorimotor impairment in at-risk populations.
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Affiliation(s)
- Sohail Ejaz
- 1 Stroke Research Group, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Julius V Emmrich
- 1 Stroke Research Group, Department of Clinical Neurosciences, University of Cambridge, UK 2 Department of Neurology, Charité - Universitätsmedizin Berlin, Germany
| | - Sergey L Sitnikov
- 1 Stroke Research Group, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Young T Hong
- 3 Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Stephen J Sawiak
- 3 Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Tim D Fryer
- 3 Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Franklin I Aigbirhio
- 3 Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, UK
| | - David J Williamson
- 3 Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Jean-Claude Baron
- 1 Stroke Research Group, Department of Clinical Neurosciences, University of Cambridge, UK 4 INSERM U894, Hôpital Sainte-Anne, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
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Solingapuram Sai KK, Gage D, Nader M, Mach RH, Mintz A. Improved Automated Radiosynthesis of [(11)C]PBR28. Sci Pharm 2015; 83:413-27. [PMID: 26839827 PMCID: PMC4727796 DOI: 10.3797/scipharm.1505-06] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 06/19/2015] [Indexed: 11/22/2022] Open
Abstract
Microglial activation is commonly identified by elevated levels of the 18 kDa translocator protein (TSPO) in response to several inflammatory processes. [(11)C]PBR28 is one of the most promising PET tracers to image TSPO in both human and non-human primates. In this study, we optimized the radiolabeling procedure of [(11)C]PBR28 for higher radiochemical yield, radiochemical purity, and specific activity, which can be easily translated to any automated module for clinical trials. Time-activity curves (TACs) derived from the dynamic PET imaging of male rhesus monkey brains demonstrated that [(11)C]PBR28 had suitable kinetics with radiotracer accumulation observed in the caudate, putamen, cerebellum, and frontal cortex region.
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Affiliation(s)
| | - Don Gage
- Department of Radiology, Wake Forest School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157, USA
| | - Mike Nader
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157, USA
| | - Robert H Mach
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Akiva Mintz
- Department of Radiology, Wake Forest School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157, USA
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Discovery of a novel site of opioid action at the innate immune pattern-recognition receptor TLR4 and its role in addiction. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 118:129-63. [PMID: 25175864 DOI: 10.1016/b978-0-12-801284-0.00006-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Opioids have historically, and continue to be, an integral component of pain management. However, despite pharmacokinetic and dynamic optimization over the past 100 years, opioids continue to produce many undesirable side effects such as tolerance, reward, and dependence. As such, opioids are liable for addiction. Traditionally, opioid addiction was viewed as a solely neuronal process, and while substantial headway has been made into understanding the molecular and cellular mechanisms mediating this process, research has however, been relatively ambivalent to how the rest of the central nervous system (CNS) responds to opioids. Evidence over the past 20 years has clearly demonstrated the importance of the immunocompetent cells of the CNS (glia) in many aspects of opioid pharmacology. Particular focus has been placed on microglia and astrocytes, who in response to opioids, become activated and release inflammatory mediators. Importantly, the mechanism underlying immune activation is beginning to be elucidated. Evidence suggests an innate immune pattern-recognition receptor (toll-like receptor 4) as an integral component underlying opioid-induced glial activation. The subsequent proinflammatory response may be viewed akin to neurotransmission creating a process termed central immune signaling. Translationally, we are beginning to appreciate the importance of central immune signaling as it contributes to many behavioral actions of addiction including reward, withdrawal, and craving. As such, the aim of this chapter is to review and integrate the neuronal and central immune signaling perspective of addiction.
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Loggia ML, Chonde DB, Akeju O, Arabasz G, Catana C, Edwards RR, Hill E, Hsu S, Izquierdo-Garcia D, Ji RR, Riley M, Wasan AD, Zürcher NR, Albrecht DS, Vangel MG, Rosen BR, Napadow V, Hooker JM. Evidence for brain glial activation in chronic pain patients. ACTA ACUST UNITED AC 2015; 138:604-15. [PMID: 25582579 DOI: 10.1093/brain/awu377] [Citation(s) in RCA: 337] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Although substantial evidence has established that microglia and astrocytes play a key role in the establishment and maintenance of persistent pain in animal models, the role of glial cells in human pain disorders remains unknown. Here, using the novel technology of integrated positron emission tomography-magnetic resonance imaging and the recently developed radioligand (11)C-PBR28, we show increased brain levels of the translocator protein (TSPO), a marker of glial activation, in patients with chronic low back pain. As the Ala147Thr polymorphism in the TSPO gene affects binding affinity for (11)C-PBR28, nine patient-control pairs were identified from a larger sample of subjects screened and genotyped, and compared in a matched-pairs design, in which each patient was matched to a TSPO polymorphism-, age- and sex-matched control subject (seven Ala/Ala and two Ala/Thr, five males and four females in each group; median age difference: 1 year; age range: 29-63 for patients and 28-65 for controls). Standardized uptake values normalized to whole brain were significantly higher in patients than controls in multiple brain regions, including thalamus and the putative somatosensory representations of the lumbar spine and leg. The thalamic levels of TSPO were negatively correlated with clinical pain and circulating levels of the proinflammatory citokine interleukin-6, suggesting that TSPO expression exerts pain-protective/anti-inflammatory effects in humans, as predicted by animal studies. Given the putative role of activated glia in the establishment and or maintenance of persistent pain, the present findings offer clinical implications that may serve to guide future studies of the pathophysiology and management of a variety of persistent pain conditions.
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Affiliation(s)
- Marco L Loggia
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA 2 Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02155, USA
| | - Daniel B Chonde
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Oluwaseun Akeju
- 3 Department of Anesthesia, Critical Care and Pain Medicine, MGH/HMS, Boston, MA 02114, USA
| | - Grae Arabasz
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Ciprian Catana
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Robert R Edwards
- 2 Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02155, USA 4 Department of Psychiatry, Brigham and Women's Hospital, HMS, Boston, MA 02155, USA
| | - Elena Hill
- 5 Tufts University School of Medicine, Boston, MA 02111, USA
| | - Shirley Hsu
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - David Izquierdo-Garcia
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Ru-Rong Ji
- 2 Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02155, USA 6 Departments of Anesthesiology and Neurobiology, Duke University Medical Center, Durham, NC 27705, USA
| | - Misha Riley
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Ajay D Wasan
- 2 Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02155, USA 4 Department of Psychiatry, Brigham and Women's Hospital, HMS, Boston, MA 02155, USA 7 Departments of Anesthesiology and Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA 15206, USA
| | - Nicole R Zürcher
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Daniel S Albrecht
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Mark G Vangel
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Bruce R Rosen
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA 8 Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Vitaly Napadow
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA 2 Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02155, USA 9 Department of Biomedical Engineering, Kyung Hee University, Seoul 130-872, Republic of Korea
| | - Jacob M Hooker
- 1 MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
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McDougle CJ, Landino SM, Vahabzadeh A, O'Rourke J, Zurcher NR, Finger BC, Palumbo ML, Helt J, Mullett JE, Hooker JM, Carlezon WA. Toward an immune-mediated subtype of autism spectrum disorder. Brain Res 2014; 1617:72-92. [PMID: 25445995 DOI: 10.1016/j.brainres.2014.09.048] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 09/15/2014] [Accepted: 09/20/2014] [Indexed: 11/25/2022]
Abstract
A role for immunological involvement in autism spectrum disorder (ASD) has long been hypothesized. This review includes four sections describing (1) evidence for a relationship between familial autoimmune disorders and ASD; (2) results from post-mortem and neuroimaging studies that investigated aspects of neuroinflammation in ASD; (3) findings from animal model work in ASD involving inflammatory processes; and (4) outcomes from trials of anti-inflammatory/immune-modulating drugs in ASD that have appeared in the literature. Following each section, ideas are provided for future research, suggesting paths forward in the continuing effort to define the role of immune factors and inflammation in the pathophysiology of a subtype of ASD. This article is part of a Special Issue entitled SI: Neuroimmunology in Health And Disease.
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Affiliation(s)
- Christopher J McDougle
- Lurie Center for Autism, Lexington, MA, United States; Massachusetts General Hospital, Boston, MA, United States; Harvard Medical School, Boston, MA, United States.
| | - Samantha M Landino
- Behavioral Genetics Laboratory, Belmont, MA, United States; McLean Hospital, Belmont, MA, United States
| | - Arshya Vahabzadeh
- Massachusetts General Hospital, Boston, MA, United States; McLean Hospital, Belmont, MA, United States; Harvard Medical School, Boston, MA, United States
| | - Julia O'Rourke
- Lurie Center for Autism, Lexington, MA, United States; Massachusetts General Hospital, Boston, MA, United States; Harvard Medical School, Boston, MA, United States
| | - Nicole R Zurcher
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States; Massachusetts General Hospital, Boston, MA, United States; Harvard Medical School, Boston, MA, United States
| | - Beate C Finger
- Behavioral Genetics Laboratory, Belmont, MA, United States; McLean Hospital, Belmont, MA, United States; Harvard Medical School, Boston, MA, United States
| | - Michelle L Palumbo
- Lurie Center for Autism, Lexington, MA, United States; Massachusetts General Hospital, Boston, MA, United States; Harvard Medical School, Boston, MA, United States
| | - Jessica Helt
- Lurie Center for Autism, Lexington, MA, United States; Massachusetts General Hospital, Boston, MA, United States
| | - Jennifer E Mullett
- Lurie Center for Autism, Lexington, MA, United States; Massachusetts General Hospital, Boston, MA, United States
| | - Jacob M Hooker
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States; Massachusetts General Hospital, Boston, MA, United States; Harvard Medical School, Boston, MA, United States
| | - William A Carlezon
- Behavioral Genetics Laboratory, Belmont, MA, United States; McLean Hospital, Belmont, MA, United States; Harvard Medical School, Boston, MA, United States
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Liu G, Middleton RJ, Hatty CR, Kam WW, Chan R, Pham T, Harrison‐Brown M, Dodson E, Veale K, Banati RB. The 18 kDa translocator protein, microglia and neuroinflammation. Brain Pathol 2014; 24:631-53. [PMID: 25345894 PMCID: PMC8029074 DOI: 10.1111/bpa.12196] [Citation(s) in RCA: 166] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 08/19/2014] [Indexed: 12/17/2022] Open
Abstract
The 18 kDa translocator protein (TSPO), previously known as the peripheral benzodiazepine receptor, is expressed in the injured brain. It has become known as an imaging marker of "neuroinflammation" indicating active disease, and is best interpreted as a nondiagnostic biomarker and disease staging tool that refers to histopathology rather than disease etiology. The therapeutic potential of TSPO as a drug target is mostly based on the understanding that it is an outer mitochondrial membrane protein required for the translocation of cholesterol, which thus regulates the rate of steroid synthesis. This pivotal role together with the evolutionary conservation of TSPO has underpinned the belief that any loss or mutation of TSPO should be associated with significant physiological deficits or be outright incompatible with life. However, against prediction, full Tspo knockout mice are viable and across their lifespan do not show the phenotype expected if cholesterol transport and steroid synthesis were significantly impaired. Thus, the "translocation" function of TSPO remains to be better substantiated. Here, we discuss the literature before and after the introduction of the new nomenclature for TSPO and review some of the newer findings. In light of the controversy surrounding the function of TSPO, we emphasize the continued importance of identifying compounds with confirmed selectivity and suggest that TSPO expression is analyzed within specific disease contexts rather than merely equated with the reified concept of "neuroinflammation."
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Affiliation(s)
- Guo‐Jun Liu
- Life SciencesAustralian Nuclear Science and Technology OrganisationNSWAustralia
- Brain & Mind Research InstituteThe University of SydneyNSWAustralia
- Discipline of Medical Imaging & Radiation SciencesFaculty of Health SciencesThe University of SydneyNSWAustralia
| | - Ryan J. Middleton
- Life SciencesAustralian Nuclear Science and Technology OrganisationNSWAustralia
| | - Claire R. Hatty
- Brain & Mind Research InstituteThe University of SydneyNSWAustralia
- Discipline of Medical Imaging & Radiation SciencesFaculty of Health SciencesThe University of SydneyNSWAustralia
| | - Winnie Wai‐Ying Kam
- Life SciencesAustralian Nuclear Science and Technology OrganisationNSWAustralia
- Brain & Mind Research InstituteThe University of SydneyNSWAustralia
- Discipline of Medical Imaging & Radiation SciencesFaculty of Health SciencesThe University of SydneyNSWAustralia
| | - Ronald Chan
- Brain & Mind Research InstituteThe University of SydneyNSWAustralia
- Discipline of Medical Imaging & Radiation SciencesFaculty of Health SciencesThe University of SydneyNSWAustralia
| | - Tien Pham
- Life SciencesAustralian Nuclear Science and Technology OrganisationNSWAustralia
| | - Meredith Harrison‐Brown
- Life SciencesAustralian Nuclear Science and Technology OrganisationNSWAustralia
- Discipline of Medical Imaging & Radiation SciencesFaculty of Health SciencesThe University of SydneyNSWAustralia
| | - Eoin Dodson
- Life SciencesAustralian Nuclear Science and Technology OrganisationNSWAustralia
| | - Kelly Veale
- Discipline of Medical Imaging & Radiation SciencesFaculty of Health SciencesThe University of SydneyNSWAustralia
| | - Richard B. Banati
- Life SciencesAustralian Nuclear Science and Technology OrganisationNSWAustralia
- Brain & Mind Research InstituteThe University of SydneyNSWAustralia
- Discipline of Medical Imaging & Radiation SciencesFaculty of Health SciencesThe University of SydneyNSWAustralia
- National Imaging Facility and Ramaciotti Brain Imaging CentreSydneyNSWAustralia
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Liu J, Buisman-Pijlman F, Hutchinson MR. Toll-like receptor 4: innate immune regulator of neuroimmune and neuroendocrine interactions in stress and major depressive disorder. Front Neurosci 2014; 8:309. [PMID: 25324715 PMCID: PMC4179746 DOI: 10.3389/fnins.2014.00309] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 09/13/2014] [Indexed: 01/06/2023] Open
Abstract
Major depressive disorder (MDD) poses one of the highest disease burdens worldwide. Yet, current treatments targeting serotonergic and noradrenaline reuptake systems are insufficient to provide long-term relief from depressive symptoms in most patients, indicating the need for new treatment targets. Having the ability to influence behavior similar to depressive symptoms, as well as communicate with neuronal and neuroendocrine systems, the innate immune system is a strong candidate for MDD treatments. Given the complex nature of immune signaling, the main question becomes: What is the role of the innate immune system in MDD? The current review presents evidence that toll-like receptor 4 (TLR4), via driving both peripheral and central immune responses, can interact with serotonergic neurotransmission and cause neuroendocrine disturbances, thus integrating with widely observed hallmarks of MDD. Additionally, through describing the multi-directional communication between immune, neural and endocrine systems in stress, TLR4—related mechanisms can mediate stress-induced adaptations, which are necessary for the development of MDD. Therefore, apart from exogenous pathogenic mechanisms, TLR4 is involved in immune changes as a result of endogenous stress signals, playing an integral part in the pathophysiology, and could be a potential target for pharmacological treatments to improve current interventions for MDD.
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Affiliation(s)
- JiaJun Liu
- Neuroimmunopharmacology Group, Discipline of Physiology, School of Medical Sciences, The University of Adelaide Adelaide, SA, Australia
| | - Femke Buisman-Pijlman
- Discipline of Pharmacology, School of Medical Sciences, The University of Adelaide Adelaide, SA, Australia
| | - Mark R Hutchinson
- Neuroimmunopharmacology Group, Discipline of Physiology, School of Medical Sciences, The University of Adelaide Adelaide, SA, Australia
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Culture and characterization of microglia from the adult murine retina. ScientificWorldJournal 2014; 2014:894368. [PMID: 24987746 PMCID: PMC4060747 DOI: 10.1155/2014/894368] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 05/12/2014] [Accepted: 05/13/2014] [Indexed: 01/11/2023] Open
Abstract
Purpose. To develop a protocol for isolating and culturing murine adult retinal microglia and to characterize the phenotype and function of the cultured cells. Method. Retinal single-cell suspensions were prepared from adult MF1 mice. Culture conditions including culture medium, growth factors, seeding cell density, and purification of microglia from the mixed cultures were optimised. Cultured retinal microglial cells were phenotyped using the surface markers CD45, CD11b, and F4/80. Their ability to secrete proinflammatory cytokines in response to lipopolysaccharide (LPS) stimulation was examined using cytometric bead array (CBA) assay. Results. Higher yield was obtained when retinal single-cell suspension was cultured at the density of 0.75 × 106 cells per cm2 in Dulbecco's modified Eagle medium (DMEM)/F12 + Glutamax supplement with 20% fetal calf serum (FCS) and 20% L929 supernatant. We identified day 10 to be the optimum day of microglial isolation. Over 98% of the cells isolated were positive for CD45, CD11b, and F4/80. After stimulating with LPS they were able to secrete proinflammatory cytokines such as IL-6 and TNF-α and express CD86, CD40, and MHC-II. Conclusion. We have developed a simple method for isolating and culturing retinal microglia from adult mice.
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Protein markers of cerebrovascular disruption of neurovascular unit: immunohistochemical and imaging approaches. Rev Neurosci 2014; 25:481-507. [DOI: 10.1515/revneuro-2013-0041] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 03/22/2014] [Indexed: 12/15/2022]
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Schlereth T, Drummond PD, Birklein F. Inflammation in CRPS: role of the sympathetic supply. Auton Neurosci 2013; 182:102-7. [PMID: 24411269 DOI: 10.1016/j.autneu.2013.12.011] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 12/11/2013] [Indexed: 12/21/2022]
Abstract
Acute Complex Regional Pain Syndrome (CRPS) is associated with signs of inflammation such as increased skin temperature, oedema, skin colour changes and pain. Pro-inflammatory cytokines (tumour necrosis factor-α (TNF-α), interleukin-2 (IL-2), IL-1beta, IL-6) are up-regulated, whereas anti-inflammatory cytokines (IL-4, IL-10) are diminished. Adaptive immunity seems to be involved in CRPS pathophysiology as many patients have autoantibodies directed against β2 adrenergic and muscarinic-2 receptors. In an animal tibial fracture model changes in the innate immune response such as up-regulation of keratinocytes are also found. Additionally, CRPS is accompanied by increased neurogenic inflammation which depends mainly on neuropeptides such as CGRP and Substance P. Besides inflammatory signs, sympathetic nervous system involvement in CRPS results in cool skin, increased sweating and sympathetically-maintained pain. The norepinephrine level is lower in the CRPS-affected than contralateral limb, but sympathetic sprouting and up-regulation of alpha-adrenoceptors may result in an adrenergic supersensitivity. The sympathetic nervous system and inflammation interact: norepinephrine influences the immune system and the production of cytokines. There is substantial evidence that this interaction contributes to the pathophysiology and clinical presentation of CRPS, but this interaction is not straightforward. How inflammation in CRPS might be exaggerated by sympathetic transmitters requires further elucidation.
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Affiliation(s)
- Tanja Schlereth
- Department of Neurology, Langenbeckstr, 1, D-55131 Mainz, Germany.
| | - Peter D Drummond
- School of Psychology and Exercise Science, Murdoch University, 6150 Western Australia, Australia
| | - Frank Birklein
- Department of Neurology, Langenbeckstr, 1, D-55131 Mainz, Germany
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Bardi G, Nunes A, Gherardini L, Bates K, Al-Jamal KT, Gaillard C, Prato M, Bianco A, Pizzorusso T, Kostarelos K. Functionalized carbon nanotubes in the brain: cellular internalization and neuroinflammatory responses. PLoS One 2013; 8:e80964. [PMID: 24260521 PMCID: PMC3832421 DOI: 10.1371/journal.pone.0080964] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 10/08/2013] [Indexed: 11/19/2022] Open
Abstract
The potential use of functionalized carbon nanotubes (f-CNTs) for drug and gene delivery to the central nervous system (CNS) and as neural substrates makes the understanding of their in vivo interactions with the neural tissue essential. The aim of this study was to investigate the interactions between chemically functionalized multi-walled carbon nanotubes (f-MWNTs) and the neural tissue following cortical stereotactic administration. Two different f-MWNT constructs were used in these studies: shortened (by oxidation) amino-functionalized MWNT (oxMWNT-NH3(+)) and amino-functionalized MWNT (MWNT-NH3(+)). Parenchymal distribution of the stereotactically injected f-MWNTs was assessed by histological examination. Both f-MWNT were uptaken by different types of neural tissue cells (microglia, astrocytes and neurons), however different patterns of cellular internalization were observed between the nanotubes. Furthermore, immunohistochemical staining for specific markers of glial cell activation (GFAP and CD11b) was performed and secretion of inflammatory cytokines was investigated using real-time PCR (qRT-PCR). Injections of both f-MWNT constructs led to a local and transient induction of inflammatory cytokines at early time points. Oxidation of nanotubes seemed to induce significant levels of GFAP and CD11b over-expression in areas peripheral to the f-MWNT injection site. These results highlight the importance of nanotube functionalization on their interaction with brain tissue that is deemed critical for the development nanotube-based vector systems for CNS applications.
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Affiliation(s)
- Giuseppe Bardi
- CNR Neuroscience Institute, Pisa Area della recerca, Pisa, Italy and Center for MicroBioRobotics, IIT@SSSA, Pontedera, Pisa, Italy
- * E-mail: (KK); (TP)
| | - Antonio Nunes
- Nanomedicine Laboratory, UCL School of Pharmacy, University College London, London, United Kingdom
| | - Lisa Gherardini
- CNR Neuroscience Institute, Pisa Area della recerca, Pisa, Italy and Center for MicroBioRobotics, IIT@SSSA, Pontedera, Pisa, Italy
- * E-mail: (KK); (TP)
| | - Katie Bates
- Nanomedicine Laboratory, UCL School of Pharmacy, University College London, London, United Kingdom
| | - Khuloud T. Al-Jamal
- Nanomedicine Laboratory, UCL School of Pharmacy, University College London, London, United Kingdom
| | - Claire Gaillard
- CNRS, Institut de Biologie Moléculaire et Cellulaire, UPR 9021 Immunologie et Chimie Thérapeutiques, Strasbourg, France
| | - Maurizio Prato
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
| | - Alberto Bianco
- CNRS, Institut de Biologie Moléculaire et Cellulaire, UPR 9021 Immunologie et Chimie Thérapeutiques, Strasbourg, France
| | - Tommaso Pizzorusso
- CNR Neuroscience Institute, Pisa Area della recerca, Pisa, Italy and Center for MicroBioRobotics, IIT@SSSA, Pontedera, Pisa, Italy
- Department of Psychology, University of Florence, Area San Salvi, Florence, Italy
- * E-mail: (KK); (TP)
| | - Kostas Kostarelos
- Nanomedicine Laboratory, UCL School of Pharmacy, University College London, London, United Kingdom
- * E-mail: (KK); (TP)
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Cooper MS, Clark VP. Neuroinflammation, neuroautoimmunity, and the co-morbidities of complex regional pain syndrome. J Neuroimmune Pharmacol 2013; 8:452-69. [PMID: 22923151 PMCID: PMC3661922 DOI: 10.1007/s11481-012-9392-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2012] [Accepted: 07/23/2012] [Indexed: 02/07/2023]
Abstract
Complex Regional Pain Syndrome (CRPS) is associated with non-dermatomal patterns of pain, unusual movement disorders, and somatovisceral dysfunctions. These symptoms are viewed by some neurologists and psychiatrists as being psychogenic in origin. Recent evidence, however, suggests that an autoimmune attack on self-antigens found in the peripheral and central nervous system may underlie a number of CRPS symptoms. From both animal and human studies, evidence is accumulating that neuroinflammation can spread, either anterograde or retrograde, via axonal projections in the CNS, thereby establishing neuroinflammatory tracks and secondary neuroinflammatory foci within the neuraxis. These findings suggest that neuroinflammatory lesions, as well as their associated functional consequences, should be evaluated during the differential diagnosis of non-dermatomal pain presentations, atypical movement disorders, as well as other "medically unexplained symptoms", which are often attributed to psychogenic illness.
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Affiliation(s)
- Mark S Cooper
- Department of Biology, University of Washington, Seattle, WA 98195-1800, USA.
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Chang L, Munsaka SM, Kraft-Terry S, Ernst T. Magnetic resonance spectroscopy to assess neuroinflammation and neuropathic pain. J Neuroimmune Pharmacol 2013; 8:576-93. [PMID: 23666436 DOI: 10.1007/s11481-013-9460-x] [Citation(s) in RCA: 199] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 04/14/2013] [Indexed: 02/07/2023]
Abstract
Proton magnetic resonance spectroscopy ((1)H MRS) has been applied to numerous clinical studies, especially for neurological disorders. This technique can non-invasively evaluate brain metabolites and neurochemicals in selected brain regions and is particularly useful for assessing neuroinflammatory disorders. Neurometabolites assessed with MRS include the neuronal markers N-acetylaspartate (NAA) and glutamate (Glu), as well as the glial marker myo-inositol (MI). Therefore, the concentrations of these metabolites typically correspond to disease severity and often correlate well with clinical variables in the various brain disorders. Neuroinflammation with activated astrocytes and microglia in brain disorders are often associated with elevated MI, and to a lesser extent elevated total creatine (tCr) and choline containing compounds (Cho), which are found in higher concentrations in glia than neurons, while neuronal injury is indicated by lower than normal levels of NAA and Glu. This review summarizes the neurometabolite abnormalities found in MRS studies performed in patients with neuroinflammatory disorders or neuropathic pain, which also may be associated with neuroinflammation. These brain disorders include multiple sclerosis, neuroviral infections (including Human Immunodeficiency virus and Hepatitis C), degenerative brain disorders (including Alzheimer's disease and Parkinson's disease), stimulant abuse (including methamphetamine and cocaine) as well as several chronic pain syndromes.
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Affiliation(s)
- Linda Chang
- Department of Medicine, John A. Burns School of Medicine, University of Hawai'i at Manoa, Neuroscience and Magnetic Resonance Research Program, The Queen's Medical Center, 1356 Lusitana Street, UH Tower 7th Floor, Honolulu, HI 96813, USA.
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Dewapriya P, Li YX, Himaya S, Pangestuti R, Kim SK. Neoechinulin A suppresses amyloid-β oligomer-induced microglia activation and thereby protects PC-12 cells from inflammation-mediated toxicity. Neurotoxicology 2013; 35:30-40. [DOI: 10.1016/j.neuro.2012.12.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Revised: 12/08/2012] [Accepted: 12/14/2012] [Indexed: 12/22/2022]
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Zhang X, Paule MG, Wang C, Slikker W. Application of microPET imaging approaches in the study of pediatric anesthetic-induced neuronal toxicity. J Appl Toxicol 2013; 33:861-8. [DOI: 10.1002/jat.2857] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 12/13/2012] [Accepted: 12/14/2012] [Indexed: 12/14/2022]
Affiliation(s)
- Xuan Zhang
- Division of Neurotoxicology; National Center for Toxicological Research (NCTR)/FDA; Jefferson; AR; USA
| | - Merle G. Paule
- Division of Neurotoxicology; National Center for Toxicological Research (NCTR)/FDA; Jefferson; AR; USA
| | - Cheng Wang
- Division of Neurotoxicology; National Center for Toxicological Research (NCTR)/FDA; Jefferson; AR; USA
| | - William Slikker
- Office of the Director; National Center for Toxicological Research (NCTR)/FDA; Jefferson; AR; USA
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Inflaming the brain: CRPS a model disease to understand neuroimmune interactions in chronic pain. J Neuroimmune Pharmacol 2012. [PMID: 23188523 DOI: 10.1007/s11481-012-9422-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We review current concepts in CRPS from a neuroimaging perspective and point out topics and potential mechanisms that are suitable to be investigated in the next step towards understanding the pathophysiology of CRPS. We have outlined functional aspects of the syndrome, from initiating lesion via inflammatory mechanisms to CNS change and associated sickness behavior, with current evidence for up-regulation of immunological factors in CRPS, neuroimaging of systemic inflammation, and neuroimaging findings in CRPS. The initiation, maintenances and CNS targets implicated in CRPS and in the neuro-inflammatory reflex are discussed in terms of CRPS symptoms and recent preclinical studies. Potential avenues for investigating CRPS with PET and fMRI are described, along with roles of inflammation, treatment and behavior in CRPS. It is our hope that this outline will provoke discussion and promote further empirical studies on the interactions between central and peripheral inflammatory pathways manifest in CRPS.
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Zhang X, Paule MG, Newport GD, Liu F, Callicott R, Liu S, Berridge MS, Apana SM, Slikker W, Wang C. MicroPET/CT Imaging of [18F]-FEPPA in the Nonhuman Primate: A Potential Biomarker of Pathogenic Processes Associated with Anesthetic-Induced Neurotoxicity. ACTA ACUST UNITED AC 2012. [DOI: 10.5402/2012/261640] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Background. The inhalation anesthetics nitrous oxide (N2O) and isoflurane (ISO) are used in surgical procedures for human infants. Injury to the central nervous system is often accompanied by localization of activated microglia or astrocytosis at the site of injury. The tracer that targets to the peripheral benzodiazepine receptor (PBR), [18F]N-2-(2-fluoroethoxy)benzyl)-N-(4-phenoxypyridin-3-yl)acetamide ([18F]-FEPPA), has been reported as a sensitive biomarker for the detection of neuronal damage/inflammation. Methods. On postnatal day (PND) 5 or 6 rhesus monkey neonates were exposed to a mixture of N2O/oxygen and ISO for 8 hours and control monkeys were exposed to room air. MicroPET/CT images with [18F]-FEPPA were obtained for each monkey 1 day, one week, three weeks, and 6 months after the anesthetic exposure. Results. The radiotracer quickly distributed into the brains of both treated and control monkeys on all scan days. One day after anesthetic exposure, the uptake of [18F]-FEPPA was significantly increased in the temporal lobe. One week after exposure, the uptake of [18F]-FEPPA in the frontal lobe of treated animals was significantly greater than that in controls. Conclusions. These findings suggest that microPET imaging is capable of dynamic detection of inhaled anesthetic-induced brain damage in different brain regions of the nonhuman primate.
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Affiliation(s)
- Xuan Zhang
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Merle G. Paule
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Glenn D. Newport
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Fang Liu
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Ralph Callicott
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Shuliang Liu
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Marc S. Berridge
- 3D Imaging, LLC, Little Rock, AR 72113, USA
- University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Scott M. Apana
- 3D Imaging, LLC, Little Rock, AR 72113, USA
- University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - William Slikker
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Cheng Wang
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
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Kumar A, Muzik O, Shandal V, Chugani D, Chakraborty P, Chugani HT. Evaluation of age-related changes in translocator protein (TSPO) in human brain using (11)C-[R]-PK11195 PET. J Neuroinflammation 2012; 9:232. [PMID: 23035793 PMCID: PMC3546876 DOI: 10.1186/1742-2094-9-232] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 09/17/2012] [Indexed: 11/09/2022] Open
Abstract
Background We studied the distribution and expression of translocator protein in the human brain using 11C-[R]-PK-11195 positron emission tomography (PK11195 PET) and evaluated age-related changes. Methods A dynamic PK11195 PET scan was performed in 15 normal healthy adults (mean age: 29 ±8.5 years (range: 20 to 49); 7 males) and 10 children (mean age: 8.8 ±5.2 years (range: 1.2 to 17); 5 males), who were studied for potential neuroinflammation but showed no focally increased PK11195 binding. The PET images were evaluated by calculating standard uptake values and regional binding potential, based on a simplified reference region model, as well as with a voxel-wise analysis using statistical parametric mapping. Results PK11195 uptake in the brain is relatively low, compared with the subcortical structures, and symmetrical. The overall pattern of PK11195 distribution in the brain does not change with age. PK11195 uptake was lowest in the frontal-parietal-temporal cortex and highest in the pituitary gland, midbrain, thalamus, basal ganglia, occipital cortex, hippocampus and cerebellum, in descending order. White matter showed negligible PK11195 uptake. Overall, brain PK11195 uptake increased with age, with midbrain and thalamus showing relatively higher increases with age compared with other brain regions. Conclusions The brain shows low PK11195 uptake, which is lower in the cortex and cerebellum compared with subcortical structures, suggesting a low level of translocator protein expression. There is no hemispheric asymmetry in PK11195 uptake and the overall pattern of PK11195 distribution in the brain does not change with age. However, brain PK11195 uptake increases with age, with the thalamus and midbrain showing relatively higher increases compared with other brain regions. This increase in uptake suggests an age-related increase in translocator protein expression or the number of cells expressing these receptors or both.
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Affiliation(s)
- Ajay Kumar
- Department of Pediatrics, School of Medicine, Children's Hospital of Michigan, Detroit Medical Center, Wayne State University, 3901 Beaubien Boulevard, Detroit, MI, USA
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