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Singh P, kumari N, Kaul A, Srivastava A, Singh VK, Srivastava K, Tiwari AK. Acetamidobenzoxazolone conjugated DOTA system for assessing 18 kDa translocator protein during pulmonary inflammation. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2022.134006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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2
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Zinnhardt B, Roncaroli F, Foray C, Agushi E, Osrah B, Hugon G, Jacobs AH, Winkeler A. Imaging of the glioma microenvironment by TSPO PET. Eur J Nucl Med Mol Imaging 2021; 49:174-185. [PMID: 33721063 DOI: 10.1007/s00259-021-05276-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 02/18/2021] [Indexed: 12/13/2022]
Abstract
Gliomas are highly dynamic and heterogeneous tumours of the central nervous system (CNS). They constitute the most common neoplasm of the CNS and the second most common cause of death from intracranial disease after stroke. The advances in detailing the genetic profile of paediatric and adult gliomas along with the progress in MRI and PET multimodal molecular imaging technologies have greatly improved prognostic stratification of patients with glioma and informed on treatment decisions. Amino acid PET has already gained broad clinical application in the study of gliomas. PET imaging targeting the translocator protein (TSPO) has recently been applied to decipher the heterogeneity and dynamics of the tumour microenvironment (TME) and its various cellular components especially in view of targeted immune therapies with the goal to delineate pro- and anti-glioma immune cell modulation. The current review provides a comprehensive overview on the historical developments of TSPO PET for gliomas and summarizes the most relevant experimental and clinical data with regard to the assessment and quantification of various cellular components with the TME of gliomas by in vivo TSPO PET imaging.
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Affiliation(s)
- Bastian Zinnhardt
- European Institute for Molecular Imaging (EIMI), Westfälische Wilhelms-University Münster (WWU), Münster, Germany
- Biomarkers and Translational Technologies, Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Federico Roncaroli
- Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Manchester, UK
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Brain and Mental Health, University of Manchester, Manchester, UK
| | - Claudia Foray
- European Institute for Molecular Imaging (EIMI), Westfälische Wilhelms-University Münster (WWU), Münster, Germany
| | - Erjon Agushi
- Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Manchester, UK
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Brain and Mental Health, University of Manchester, Manchester, UK
| | - Bahiya Osrah
- Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Manchester, UK
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Brain and Mental Health, University of Manchester, Manchester, UK
| | - Gaëlle Hugon
- Laboratoire d'Imagerie Biomédicale Multimodale (BioMaps), CEA, CNRS, Inserm, Université Paris-Saclay, Orsay, France
| | - Andreas H Jacobs
- European Institute for Molecular Imaging (EIMI), Westfälische Wilhelms-University Münster (WWU), Münster, Germany
- Department of Geriatrics and Neurology, Johanniter Hospital, Bonn, Germany
| | - Alexandra Winkeler
- Laboratoire d'Imagerie Biomédicale Multimodale (BioMaps), CEA, CNRS, Inserm, Université Paris-Saclay, Orsay, France.
- CEA, DRF, JOLIOT, SHFJ, Orsay, France.
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Tournier BB, Tsartsalis S, Ceyzériat K, Fraser BH, Grégoire MC, Kövari E, Millet P. Astrocytic TSPO Upregulation Appears Before Microglial TSPO in Alzheimer's Disease. J Alzheimers Dis 2021; 77:1043-1056. [PMID: 32804124 PMCID: PMC7683091 DOI: 10.3233/jad-200136] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Background: In vivo PET/SPECT imaging of neuroinflammation is primarily based on the estimation of the 18 kDa-translocator-protein (TSPO). However, TSPO is expressed by different cell types which complicates the interpretation. Objective: The present study evaluates the cellular origin of TSPO alterations in Alzheimer’s disease (AD). Methods: The TSPO cell origin was evaluated by combining radioactive imaging approaches using the TSPO radiotracer [125I]CLINDE and fluorescence-activated cell sorting, in a rat model of AD (TgF344-AD) and in AD subjects. Results: In the hippocampus of TgF344-AD rats, TSPO overexpression not only concerns glial cells but the increase is visible at 12 and 24 months in astrocytes and only at 24 months in microglia. In the temporal cortex of AD subjects, TSPO upregulation involved only glial cells. However, the mechanism of this upregulation appears different with an increase in the number of TSPO binding sites per cell without cell proliferation in the rat, and a microglial cell population expansion with a constant number of binding sites per cell in human AD. Conclusion: These data indicate an earlier astrocyte intervention than microglia and that TSPO in AD probably is an exclusive marker of glial activity without interference from other TSPO-expressing cells. This observation indicates that the interpretation of TSPO imaging depends on the stage of the pathology, and highlights the particular role of astrocytes.
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Affiliation(s)
- Benjamin B Tournier
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Switzerland
| | - Stergios Tsartsalis
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Switzerland
| | - Kelly Ceyzériat
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Switzerland.,Division of Nuclear medicine, University Hospitals of Geneva, Switzerland
| | - Ben H Fraser
- ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Sydney, NSW, Australia
| | - Marie-Claude Grégoire
- ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Sydney, NSW, Australia
| | - Enikö Kövari
- Division of Geriatric Psychiatry, Department of Mental Health and Psychiatry, University Hospitals of Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Switzerland
| | - Philippe Millet
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Switzerland
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Tournier B, Ceyzériat K, Bouteldja FN, Millet P. Amyloid and Tau Induce Cell Death Independently of TSPO Polymerization and Density Changes. ACS OMEGA 2021; 6:18719-18727. [PMID: 34337211 PMCID: PMC8319921 DOI: 10.1021/acsomega.1c01678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
Apoptosis-dependent cell death of astrocytes has been described in Alzheimer's disease and is linked to the presence of two markers of the pathology: the β-amyloid peptide (Aβ) and the hyperphosphorylated Tau protein. Astrocytes also show reactive states characterized by the overexpression of the 18 kDa translocator protein (TSPO). However, TSPO is also known, in other areas of research, to participate in cell proliferation and death. Regulation of its function by autopolymerization has been described, but its involvement in apoptosis remains unknown. The aim was to determine the effects of Aβ, Tau, and TSPO antagonists on proliferation/cell death and TSPO polymerization in the C6 astrocytic cell line. The dose-effect on cell death in response to Aβ and Tau was observed but without alterations of TSPO density and polymerization. In contrast, nanomolar doses of antagonists stimulated cell proliferation, although micromolar doses induced cell death with a reduction in TSPO density and an increase in the ratio between the 36 and the 72 kDa TSPO polymers. Therefore, an alteration in the density and polymerization of TSPO appears to be related to cell death induced by TSPO antagonisms. In contrast, Aβ- and Tau-induced death seems to be independent of TSPO alterations. In conclusion, even if its role in cell death and proliferation is demonstrated, TSPO seems to, in the context of Alzheimer's disease, rather represent a marker of the activity of astrocytes than of cell death.
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Affiliation(s)
- Benjamin
B. Tournier
- Department
of Psychiatry, University Hospitals of Geneva, 1205 Genève, Switzerland
- Department
of Psychiatry, University of Geneva, 1211 Genève, Switzerland
| | - Kelly Ceyzériat
- Department
of Psychiatry, University Hospitals of Geneva, 1205 Genève, Switzerland
- Department
of Psychiatry, University of Geneva, 1211 Genève, Switzerland
- Division
of Nuclear Medicine and Molecular Imaging, Diagnostic Department, University Hospitals of Geneva, 1205 Genève, Switzerland
- Division
of Radiation Oncology, Department of Oncology, University Hospitals of Geneva, 1205 Genève, Switzerland
| | - Farha N. Bouteldja
- Department
of Psychiatry, University Hospitals of Geneva, 1205 Genève, Switzerland
- Department
of Psychiatry, University of Geneva, 1211 Genève, Switzerland
| | - Philippe Millet
- Department
of Psychiatry, University Hospitals of Geneva, 1205 Genève, Switzerland
- Department
of Psychiatry, University of Geneva, 1211 Genève, Switzerland
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Ceyzériat K, Gloria Y, Tsartsalis S, Fossey C, Cailly T, Fabis F, Millet P, Tournier BB. Alterations in dopamine system and in its connectivity with serotonin in a rat model of Alzheimer's disease. Brain Commun 2021; 3:fcab029. [PMID: 34286270 PMCID: PMC8287930 DOI: 10.1093/braincomms/fcab029] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/20/2021] [Accepted: 01/22/2021] [Indexed: 12/20/2022] Open
Abstract
Dopamine pathways alterations are reported in Alzheimer’s disease. However, it is
difficult in humans to establish when these deficits appear and their impact in the course
of Alzheimer’s disease. In the TgF344-Alzheimer’s disease rat model at the age of
6 months, we showed a reduction in in vivo release of striatal dopamine
due to serotonin 5HT2A-receptor blockade, in the absence of alterations in
5HT2A-receptor binding, suggesting a reduction in
5HT2A-receptor-dopamine system connectivity. In addition, a functional
hypersensitivity of postsynaptic dopamine D2-receptors and
D2-autoreceptors was also reported without any change in D2-receptor
density and in the absence of amyloid plaques or overexpression of the 18 kDa translocator
protein (an inflammatory marker) in areas of the dopamine system. Citalopram, a selective
serotonin reuptake inhibitor, induced functional
5HT2A-receptor−D2-receptor connectivity changes but had no effect on
D2-autoreceptor hypersensitivity. In older rats, dopamine cell bodies
overexpressed translocator protein and dopamine projection sites accumulated amyloid.
Interestingly, the 5HT2A-receptor density is decreased in the accumbens
subdivisions and the substantia nigra pars compacta. This reduction in the striatum is
related to the astrocytic expression of 5HT2A-receptor. Our results indicate
that both serotonin/dopamine connectivity and dopamine signalling pathways are
dysregulated and potentially represent novel early diagnostic and therapeutic avenues.
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Affiliation(s)
- Kelly Ceyzériat
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, 1206 Geneva, Switzerland.,Division of Nuclear medicine, Diagnostic Department, University Hospitals and Geneva University of Geneva, 1206 Geneva, Switzerland.,Division of Radiation Oncology, Department of Oncology, University Hospitals of Geneva, 1206 Geneva, Switzerland
| | - Yesica Gloria
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, 1206 Geneva, Switzerland
| | - Stergios Tsartsalis
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, 1206 Geneva, Switzerland
| | - Christine Fossey
- Normandie University, UNICAEN, Centre d'Etudes et de Recherche sur le Médicament de Normandie (CERMN), 14000 Caen, France
| | - Thomas Cailly
- Normandie University, UNICAEN, Centre d'Etudes et de Recherche sur le Médicament de Normandie (CERMN), 14000 Caen, France.,Department of Nuclear Medicine, CHU Cote de Nacre, 14000 Caen, France.,Normandie University, UNICAEN, IMOGERE, 14000 Caen, France
| | - Frédéric Fabis
- Normandie University, UNICAEN, Centre d'Etudes et de Recherche sur le Médicament de Normandie (CERMN), 14000 Caen, France
| | - Philippe Millet
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, 1206 Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Geneva, Switzerland
| | - Benjamin B Tournier
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, 1206 Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Geneva, Switzerland
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Tsartsalis S, Tournier BB, Millet P. In vivo absolute quantification of striatal and extrastriatal D 2/3 receptors with [ 123I]epidepride SPECT. EJNMMI Res 2020; 10:66. [PMID: 32548681 PMCID: PMC7297889 DOI: 10.1186/s13550-020-00650-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 05/27/2020] [Indexed: 01/08/2023] Open
Abstract
Background [123I]epidepride is a high-affinity radiotracer used in single-photon emission computed tomography (SPECT) imaging of the D2/3 receptors. It binds with high affinity to striatal and extrastriatal receptors. Nevertheless, its slow kinetics in the striatum impedes quantification in this region. Thus, an approach that would allow a simultaneous quantification of both striatal and extrastriatal D2/3 receptors would be of interest for preclinical and clinical SPECT neuroimaging. We describe a partial saturation protocol that allows us to produce an in vivo Scatchard plot and thus estimate Bavail and appKd separately in both striatal and extrastriatal regions, through a single dynamic SPECT session. To validate this approach, a multi-injection protocol is used for the full kinetic modeling of [123I]epidepride using a two-tissue compartment, 5-parameter model (2T-5k). Methods Eighteen male rats were used. Binding parameters were estimated using the multi-injection protocol. Various simulations were performed to estimate the optimal conditions for the partial saturation protocol, which was applied at the region and voxel level. The results of the partial saturation study were compared to those obtained with the 2T-5k model. To illustrate the interest of the partial saturation approach, we performed a preliminary study of the effect of a chronic, subcutaneous administration of haloperidol (1 mg/kg/day), a D2 receptor antagonist, on the Bavail of [123I]epidepride in the rat striatum. Results A series of simulations demonstrated that a mass of 3 ug/kg of unlabeled epidepride allows the formation of an in vivo Scatchard plot. The partial saturation study led to robust estimations of Bavail in all brain regions that highly correlated (r = 0.99) with the corresponding values from the multi-injection study. A chronic haloperidol treatment resulted in a 17.9% increase in the Bavail values in the left Caudate Putamen nucleus (CP) (p = 0.07) and a 13.8% increase in the right CP (p = 0.12). Conclusion A partial saturation method allowed the robust quantification of D2/3 receptors in striatal and extrastriatal D2/3 receptors with a single-scan approach. This approach may be applied in the mapping of the D2/3 receptor in translational biological studies and potentially, in clinical SPECT imaging.
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Affiliation(s)
- Stergios Tsartsalis
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Chemin du Petit-Bel-Air 2, CH1226, Thônex, Switzerland.,Division of Psychiatric Specialties, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
| | - Benjamin B Tournier
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Chemin du Petit-Bel-Air 2, CH1226, Thônex, Switzerland
| | - Philippe Millet
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Chemin du Petit-Bel-Air 2, CH1226, Thônex, Switzerland. .,Department of Psychiatry, University of Geneva, Geneva, Switzerland.
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7
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Tournier BB, Tsartsalis S, Ceyzériat K, Medina Z, Fraser BH, Grégoire MC, Kövari E, Millet P. Fluorescence-activated cell sorting to reveal the cell origin of radioligand binding. J Cereb Blood Flow Metab 2020; 40:1242-1255. [PMID: 31242048 PMCID: PMC7238369 DOI: 10.1177/0271678x19860408] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many studies have explored the role of TSPO (18 kDa translocator protein) as a marker of neuroinflammation using single-photon emission computed tomography (SPECT) or positron emission tomography (PET). In vivo imaging does not allow to determine the cells in which TSPO is altered. We propose a methodology based on fluorescence-activated cell sorting to sort different cell types of radioligand-treated tissues. We compared left/right hippocampus of rats in response to a unilateral injection of lipopolysaccharide (LPS), ciliary neurotrophic factor (CNTF) or saline. We finally applied this methodology in human samples (Alzheimer's disease patients and controls). Our data show that the pattern of TSPO overexpression differs across animal models of acute neuroinflammation. LPS induces a microglial expansion and an increase in microglial TSPO binding. CNTF is associated with an increase in TSPO binding in microglia and astrocytes in association with an increase in the number of microglial binding sites per cell. In humans, we show that the increase in CLINDE binding in Alzheimer's disease concerns microglia and astrocytes in the presence of a microglial expansion. Thus, the cellular basis of TSPO overexpression is condition dependent, and alterations in TSPO binding found in PET/SPECT imaging studies cannot be attributed to particular cell types indiscriminately.
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Affiliation(s)
- Benjamin B Tournier
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
| | - Stergios Tsartsalis
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
| | - Kelly Ceyzériat
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland.,Division of Nuclear medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - Zadith Medina
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
| | - Ben H Fraser
- ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation, Sydney, NSW, Australia
| | - Marie-Claude Grégoire
- ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation, Sydney, NSW, Australia
| | - Enikö Kövari
- Division of Geriatric Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Geneva, Switzerland
| | - Philippe Millet
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Geneva, Switzerland
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Tournier BB, Tsartsalis S, Rigaud D, Fossey C, Cailly T, Fabis F, Pham T, Grégoire MC, Kövari E, Moulin-Sallanon M, Savioz A, Millet P. TSPO and amyloid deposits in sub-regions of the hippocampus in the 3xTgAD mouse model of Alzheimer’s disease. Neurobiol Dis 2019; 121:95-105. [DOI: 10.1016/j.nbd.2018.09.022] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 09/03/2018] [Accepted: 09/23/2018] [Indexed: 11/16/2022] Open
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Abstract
Background Central nervous system (CNS) tumors are a rare but devastating malignancy, often robbing patients of the basic quality of life. Despite advances in our understanding of the CNS tumor disease processes, the prognosis for patients with CNS tumors remains poor. Better characterization and diagnostic and monitoring approaches are necessary to assist in diagnosis and treatment of CNS tumors. One important tool in the neuro-oncology armamentarium is the use of advanced imaging techniques. Methods We searched PubMed using the keywords neuro-oncology imaging, pseudoprogression, molecular imaging, and biomarkers. We limited our search to full-text English articles and identified other relevant articles from the reference lists of previously identified articles. Results Advances in imaging techniques have allowed investigators to explore various imaging modalities, from tumor characterization to differentiating pseudoprogression from tumor progression. Better imaging can result in better diagnostic approaches, greater and safer resection techniques, and improved monitoring of tumor progression. Conclusion This review highlights advances in neuro-oncology imaging techniques and their clinical utility in the treatment and management of primary brain tumors.
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Tsartsalis S, Tournier BB, Habiby S, Ben Hamadi M, Barca C, Ginovart N, Millet P. Dual-radiotracer translational SPECT neuroimaging. Comparison of three methods for the simultaneous brain imaging of D2/3 and 5-HT2A receptors. Neuroimage 2018; 176:528-540. [DOI: 10.1016/j.neuroimage.2018.04.063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 03/11/2018] [Accepted: 04/27/2018] [Indexed: 12/27/2022] Open
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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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12
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Jensen P, Feng L, Law I, Svarer C, Knudsen GM, Mikkelsen JD, de Nijs R, Larsen VA, Dyssegaard A, Thomsen G, Fischer W, Guilloteau D, Pinborg LH. TSPO Imaging in Glioblastoma Multiforme: A Direct Comparison Between 123I-CLINDE SPECT, 18F-FET PET, and Gadolinium-Enhanced MR Imaging. J Nucl Med 2015; 56:1386-90. [PMID: 26182972 DOI: 10.2967/jnumed.115.158998] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 07/06/2015] [Indexed: 12/22/2022] Open
Abstract
UNLABELLED Here we compare translocator protein (TSPO) imaging using 6-chloro-2-(4'-(123)I-iodophenyl)-3-(N,N-diethyl)-imidazo[1,2-a]pyridine-3-acetamide SPECT ((123)I-CLINDE) and amino acid transport imaging using O-(2-(18)F-fluoroethyl)-l-tyrosine PET ((18)F-FET) and investigate whether (123)I-CLINDE is superior to (18)F-FET in predicting progression of glioblastoma multiforme (GBM) at follow-up. METHODS Three patients with World Health Organization grade IV GBM were scanned with (123)I-CLINDE SPECT, (18)F-FET PET, and gadolinium-enhanced MR imaging. Molecular imaging data were compared with follow-up gadolinium-enhanced MR images or contrast-enhanced CT scans. RESULTS The percentage overlap between volumes of interest (VOIs) of increased (18)F-FET uptake and (123)I-CLINDE binding was variable (12%-42%). The percentage overlap of MR imaging baseline VOIs was greater for (18)F-FET (79%-93%) than (123)I-CLINDE (15%-30%). In contrast, VOIs of increased contrast enhancement at follow-up compared with baseline overlapped to a greater extent with baseline (123)I-CLINDE VOIs than (18)F-FET VOIs (21% vs. 8% and 72% vs. 55%). CONCLUSION Our preliminary results suggest that TSPO brain imaging in GBM may be a useful tool for predicting tumor progression at follow-up and may be less susceptible to changes in blood-brain barrier permeability than (18)F-FET. Larger studies are warranted to test the clinical potential of TSPO imaging in GBM, including presurgical planning and radiotherapy.
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Affiliation(s)
- Per Jensen
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark
| | - Ling Feng
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark
| | - Ian Law
- Department of Clinical Physiology, Nuclear Medicine, and PET, Rigshospitalet, Copenhagen, Denmark
| | - Claus Svarer
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark
| | | | - Robin de Nijs
- Department of Clinical Physiology, Nuclear Medicine, and PET, Rigshospitalet, Copenhagen, Denmark
| | - Vibeke A Larsen
- Department of Radiology, Rigshospitalet, Copenhagen, Denmark
| | | | - Gerda Thomsen
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark
| | - Walter Fischer
- Department of Neurosurgery, Rigshospitalet, Copenhagen, Denmark
| | - Denis Guilloteau
- Université François-Rabelais de Tours, INSERM U930 "Imaging and Brain," Tours, France; and
| | - Lars H Pinborg
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark Epilepsy Clinic, Department of Neurology, Rigshospitalet, Copenhagen, Denmark
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