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Tseng CEJ, Canales C, Marcus RE, Parmar AJ, Hightower BG, Mullett JE, Makary MM, Tassone AU, Saro HK, Townsend PH, Birtwell K, Nowinski L, Thom RP, Palumbo ML, Keary C, Catana C, McDougle CJ, Hooker JM, Zürcher NR. In vivo translocator protein in females with autism spectrum disorder: a pilot study. Neuropsychopharmacology 2024; 49:1193-1201. [PMID: 38615126 PMCID: PMC11109261 DOI: 10.1038/s41386-024-01859-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 03/21/2024] [Accepted: 04/02/2024] [Indexed: 04/15/2024]
Abstract
Sex-based differences in the prevalence of autism spectrum disorder (ASD) are well-documented, with a male-to-female ratio of approximately 4:1. The clinical presentation of the core symptoms of ASD can also vary between sexes. Previously, positron emission tomography (PET) studies have identified alterations in the in vivo levels of translocator protein (TSPO)-a mitochondrial protein-in primarily or only male adults with ASD, with our group reporting lower TSPO relative to whole brain mean in males with ASD. However, whether in vivo TSPO levels are altered in females with ASD, specifically, is unknown. This is the first pilot study to measure in vivo TSPO in the brain in adult females with ASD using [11C]PBR28 PET-magnetic resonance imaging (MRI). Twelve adult females with ASD and 10 age- and TSPO genotype-matched controls (CON) completed one or two [11C]PBR28 PET-MRI scans. Females with ASD exhibited elevated [11C]PBR28 standardized uptake value ratio (SUVR) in the midcingulate cortex and splenium of the corpus callosum compared to CON. No brain area showed lower [11C]PBR28 SUVR in females with ASD compared to CON. Test-retest over several months showed stable [11C]PBR28 SUVR across time in both groups. Elevated regional [11C]PBR28 SUVR in females with ASD stand in stark contrast to our previous findings of lower regional [11C]PBR28 SUVR in males with ASD. Preliminary evidence of regionally elevated mitochondrial protein TSPO relative to whole brain mean in ASD females may reflect neuroimmuno-metabolic alterations specific to females with ASD.
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Affiliation(s)
- Chieh-En Jane Tseng
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Camila Canales
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Rachel E Marcus
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Anjali J Parmar
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Baileigh G Hightower
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Jennifer E Mullett
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
- Department of Pediatrics, Indiana University, Indianapolis, IN, USA
| | - Meena M Makary
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Systems and Biomedical Engineering Department, Faculty of Engineering, Cairo University, Cairo, Egypt
| | - Alison U Tassone
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Hannah K Saro
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Paige Hickey Townsend
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Kirstin Birtwell
- Harvard Medical School, Boston, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Lisa Nowinski
- Harvard Medical School, Boston, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Robyn P Thom
- Harvard Medical School, Boston, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Michelle L Palumbo
- Harvard Medical School, Boston, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Christopher Keary
- Harvard Medical School, Boston, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Ciprian Catana
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Christopher J McDougle
- Harvard Medical School, Boston, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Jacob M Hooker
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - Nicole R Zürcher
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA.
- Harvard Medical School, Boston, MA, USA.
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA.
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Giladi M, Montgomery AP, Kassiou M, Danon JJ. Structure-based drug design for TSPO: Challenges and opportunities. Biochimie 2024:S0300-9084(24)00120-2. [PMID: 38782353 DOI: 10.1016/j.biochi.2024.05.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/27/2024] [Accepted: 05/21/2024] [Indexed: 05/25/2024]
Abstract
The translocator protein 18 kDa (TSPO) is an evolutionarily conserved mitochondrial transmembrane protein implicated in various neuropathologies and inflammatory conditions, making it a longstanding diagnostic and therapeutic target of interest. Despite the development of various classes of TSPO ligand chemotypes, and the elucidation of bacterial and non-human mammalian experimental structures, many unknowns exist surrounding its differential structural and functional features in health and disease. There are several limitations associated with currently used computational methodologies for modelling the native structure and ligand-binding behaviour of this enigmatic protein. In this perspective, we provide a critical analysis of the developments in the uses of these methods, outlining their uses, inherent limitations, and continuing challenges. We offer suggestions of unexplored opportunities that exist in the use of computational methodologies which offer promise for enhancing our understanding of the TSPO.
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Affiliation(s)
- Mia Giladi
- School of Chemistry, The University of Sydney, 2050, Sydney, NSW, Australia
| | | | - Michael Kassiou
- School of Chemistry, The University of Sydney, 2050, Sydney, NSW, Australia.
| | - Jonathan J Danon
- School of Chemistry, The University of Sydney, 2050, Sydney, NSW, Australia.
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3
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Xue L, Jie CVML, Desrayaud S, Auberson YP. Developing Low Molecular Weight PET and SPECT Imaging Agents. ChemMedChem 2024:e202400094. [PMID: 38634545 DOI: 10.1002/cmdc.202400094] [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: 02/01/2024] [Revised: 04/17/2024] [Accepted: 04/17/2024] [Indexed: 04/19/2024]
Abstract
Imaging agents for positron emission tomography (PET) and single-photon emission computerized tomography (SPECT) have shown their utility in many situations, answering clinical questions related to drug development and medical considerations. The discovery and development of imaging agents follow a well-understood process, with variations related to available starting points and to the envisaged imaging application. This article describes the general development path leading from the expression of an imaging need and project initiation to a clinically usable imaging agent. The definition of the project rationale, the design and optimization of early leads, and the assessment of the imaging potential of an imaging agent candidate are followed by preclinical and clinical development activities that differ from those required for therapeutic agents. These include radiolabeling with a positron emitter and first-in-human clinical studies, to rapidly evaluate the ability of a new imaging agent to address the questions it was designed to answer.
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Affiliation(s)
- Lian Xue
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade Parkville, Victoria 3052, Australia
| | - Caitlin V M L Jie
- ETH Zürich, Department of Chemistry and Applied Biosciences Center for Radiopharmaceutical Sciences, Vladimir-Prelog Weg 1-5/10, 8093, Zürich, Switzerland
| | - Sandrine Desrayaud
- Novartis Biomedical Research, In Vivo preclinical PK/ADME, Novartis campus, WSJ-352/6/73.01, 4056, Basel, Switzerland
| | - Yves P Auberson
- Novartis Biomedical Research, Global Discovery Chemistry, Novartis campus, WSJ-88.10.100, 4056, Basel, Switzerland
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Ibrahim W, An J, Yang Y, Cosgrove KP, Matuskey D. Does seasonal variation affect the neuroimmune system? A retrospective [ 11C]PBR28 PET study in healthy individuals. Neurosci Lett 2024; 828:137766. [PMID: 38583505 PMCID: PMC11073647 DOI: 10.1016/j.neulet.2024.137766] [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: 12/14/2023] [Revised: 03/31/2024] [Accepted: 04/04/2024] [Indexed: 04/09/2024]
Abstract
INTRODUCTION The neuroimmune system performs a wide range of functions in the brain and the central nervous system. The microglial translocator protein (TSPO) has an established role as a cell marker in identification of the neuroimmune system. Previously, human studies have shown TSPO differences in neuropsychiatric disorders. Seasonal variability has also been demonstrated in multiple systems of healthy individuals. Therefore, in this study, we attempt to understand whether seasonal changes affect brain TSPO levels using [11C]PBR28 positron emission tomography (PET) imaging. METHODS 46 healthy subjects (mean age ± SD = 32.5 ± 10); sex (M/F) = 32/14)) underwent PET imaging with [11C]PBR28 in a retrospectively conducted analysis. All PET scans were performed on the HRRT scanner. Volume of distribution (VT) values were generated for cortical and subcortical regions and the cerebellum. Spring/summer months were defined as March to August while fall/winter months were defined as September to February and were compared through 2-tailed t-tests (SciPy library v.1.10.1 and Pinguoin library on Python v.3.8.8). Average daylight hours and temperature in New Haven, CT were obtained online (www.wunderground.com) and compared to VT with Spearman's correlations. RESULTS There were no significant differences observed between the TSPO levels of spring/summer and fall/winter months in the brain (t = 0.52, p = 0.61). Additional analysis on all individual brain regions also indicated non-significance. Likewise, no significant correlations were found between TSPO levels in the whole brain and brain regions against daylight hours (ρ= 0.05, p = 0.74), temperature (ρ = 0.04, p = 0.81), or month (ρ = 0.08, p = 0.60). Controlling TSPO gene polymorphisms and other variables had no significant effect on the outcome. CONCLUSION To the best of our knowledge, this is the first human study to investigate seasonal changes in TSPO expression. Our results can be interpreted as the lack of seasonal variability in the neuroimmune system, but important limitations include high interindividual variability, test-retest variability, specificity of the tracer, and a limited sample size. Limitations notwithstanding, our results conclude that TSPO levels in the brain are not impacted by light and temperature changes in different seasons.
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Affiliation(s)
- Waleed Ibrahim
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut
| | - Jeonghyun An
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut
| | - Yanghong Yang
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut
| | - Kelly P. Cosgrove
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - David Matuskey
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut
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Rossano SM, Johnson AS, Smith A, Ziaggi G, Roetman A, Guzman D, Okafor A, Klein J, Tomljanovic Z, Stern Y, Brickman AM, Lee S, Kreisl WC, Lao P. Microglia measured by TSPO PET are associated with Alzheimer's disease pathology and mediate key steps in a disease progression model. Alzheimers Dement 2024; 20:2397-2407. [PMID: 38298155 PMCID: PMC11032543 DOI: 10.1002/alz.13699] [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: 06/08/2023] [Revised: 10/30/2023] [Accepted: 12/18/2023] [Indexed: 02/02/2024]
Abstract
INTRODUCTION Evidence suggests microglial activation precedes regional tau and neurodegeneration in Alzheimer's disease (AD). We characterized microglia with translocator protein (TSPO) positron emission tomography (PET) within an AD progression model where global amyloid beta (Aβ) precedes local tau and neurodegeneration, resulting in cognitive impairment. METHODS Florbetaben, PBR28, and MK-6240 PET, T1 magnetic resonance imaging, and cognitive measures were performed in 19 cognitively unimpaired older adults and 22 patients with mild cognitive impairment or mild AD to examine associations among microglia activation, Aβ, tau, and cognition, adjusting for neurodegeneration. Mediation analyses evaluated the possible role of microglial activation along the AD progression model. RESULTS Higher PBR28 uptake was associated with higher Aβ, higher tau, and lower MMSE score, independent of neurodegeneration. PBR28 mediated associations between tau in early and middle Braak stages, between tau and neurodegeneration, and between neurodegeneration and cognition. DISCUSSION Microglia are associated with AD pathology and cognition and may mediate relationships between subsequent steps in AD progression.
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Affiliation(s)
- Samantha M. Rossano
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Aubrey S. Johnson
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Anna Smith
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Galen Ziaggi
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Andrew Roetman
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Diana Guzman
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Amarachukwu Okafor
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Julia Klein
- Department of Anesthesiology and Perioperative MedicineUniversity of California Los Angeles HealthLos AngelesCaliforniaUSA
| | - Zeljko Tomljanovic
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Yaakov Stern
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Adam M. Brickman
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Seonjoo Lee
- Department of Psychiatry and BiostatisticsColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - William C. Kreisl
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Patrick Lao
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging BrainColumbia University Irving Medical CenterNew YorkNew YorkUSA
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Baglini E, Poggetti V, Cavallini C, Petroni D, Forini F, Nicolini G, Barresi E, Salerno S, Costa B, Iozzo P, Neglia D, Menichetti L, Taliani S, Da Settimo F. Targeting the Translocator Protein (18 kDa) in Cardiac Diseases: State of the Art and Future Opportunities. J Med Chem 2024; 67:17-37. [PMID: 38113353 PMCID: PMC10911791 DOI: 10.1021/acs.jmedchem.3c01716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 11/16/2023] [Accepted: 11/24/2023] [Indexed: 12/21/2023]
Abstract
Mitochondria dysfunctions are typical hallmarks of cardiac disorders (CDs). The multiple tasks of this energy-producing organelle are well documented, but its pathophysiologic involvement in several manifestations of heart diseases, such as altered electromechanical coupling, excitability, and arrhythmias, is still under investigation. The human 18 kDa translocator protein (TSPO) is a protein located on the outer mitochondrial membrane whose expression is altered in different pathological conditions, including CDs, making it an attractive therapeutic and diagnostic target. Currently, only a few TSPO ligands are employed in CDs and cardiac imaging. In this Perspective, we report an overview of the emerging role of TSPO at the heart level, focusing on the recent literature concerning the development of TSPO ligands used for fighting and imaging heart-related disease conditions. Accordingly, targeting TSPO might represent a successful strategy to achieve novel therapeutic and diagnostic strategies to unravel the fundamental mechanisms and to provide solutions to still unanswered questions in CDs.
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Affiliation(s)
- Emma Baglini
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Valeria Poggetti
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Chiara Cavallini
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Debora Petroni
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Francesca Forini
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Giuseppina Nicolini
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Elisabetta Barresi
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Silvia Salerno
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Barbara Costa
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Patricia Iozzo
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Danilo Neglia
- Fondazione
CNR/Regione Toscana Gabriele Monasterio, Cardiovascular and Imaging
Departments, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Luca Menichetti
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Sabrina Taliani
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Federico Da Settimo
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
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Uzuegbunam BC, Rummel C, Librizzi D, Culmsee C, Hooshyar Yousefi B. Radiotracers for Imaging of Inflammatory Biomarkers TSPO and COX-2 in the Brain and in the Periphery. Int J Mol Sci 2023; 24:17419. [PMID: 38139248 PMCID: PMC10743508 DOI: 10.3390/ijms242417419] [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: 10/24/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
Inflammation involves the activation of innate immune cells and is believed to play an important role in the development and progression of both infectious and non-infectious diseases such as neurodegeneration, autoimmune diseases, pulmonary and cancer. Inflammation in the brain is marked by the upregulation of translocator protein (TSPO) in microglia. High TSPO levels are also found, for example, in macrophages in cases of rheumatoid arthritis and in malignant tumor cells compared to their relatively low physiological expression. The same applies for cyclooxgenase-2 (COX-2), which is constitutively expressed in the kidney, brain, thymus and gastrointestinal tract, but induced in microglia, macrophages and synoviocytes during inflammation. This puts TSPO and COX-2 in the spotlight as important targets for the diagnosis of inflammation. Imaging modalities, such as positron emission tomography and single-photon emission tomography, can be used to localize inflammatory processes and to track their progression over time. They could also enable the monitoring of the efficacy of therapy and predict its outcome. This review focuses on the current development of PET and SPECT tracers, not only for the detection of neuroinflammation, but also for emerging diagnostic measures in infectious and other non-infectious diseases such as rheumatic arthritis, cancer, cardiac inflammation and in lung diseases.
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Affiliation(s)
| | - Christoph Rummel
- Institute of Veterinary Physiology and Biochemistry, Justus Liebig University Giessen, 35392 Gießen, Germany;
- Center for Mind Brain and Behavior, Universities Giessen and Marburg, 35043 Marburg, Germany;
| | - Damiano Librizzi
- Department of Nuclear Medicine, Philipps University of Marburg, 35043 Marburg, Germany;
| | - Carsten Culmsee
- Center for Mind Brain and Behavior, Universities Giessen and Marburg, 35043 Marburg, Germany;
- Institute of Pharmacology and Clinical Pharmacy, Philipps University of Marburg, 35037 Marburg, Germany
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8
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Schoenberg PLA, Song AK, Mohr EM, Rogers BP, Peterson TE, Murphy BA. Increased microglia activation in late non-central nervous system cancer survivors links to chronic systemic symptomatology. Hum Brain Mapp 2023; 44:6001-6019. [PMID: 37751068 PMCID: PMC10619383 DOI: 10.1002/hbm.26491] [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: 02/03/2023] [Revised: 08/21/2023] [Accepted: 09/06/2023] [Indexed: 09/27/2023] Open
Abstract
Prolonged inflammatory expression within the central nervous system (CNS) is recognized by the brain as a molecular signal of "sickness", that has knock-on effects to the blood-brain barrier, brain-spinal barrier, blood-cerebrospinal fluid barrier, neuro-axonal structures, neurotransmitter activity, synaptic plasticity, neuroendocrine function, and resultant systemic symptomatology. It is concurred that the inflammatory process associated with cancer and cancer treatments underline systemic symptoms present in a large portion of survivors, although this concept is largely theoretical from disparate and indirect evidence and/or clinical anecdotal reports. We conducted a proof-of-concept study to link for the first time late non-CNS cancer survivors presenting chronic systemic symptoms and the presence of centralized inflammation, or neuroinflammation, using TSPO-binding PET tracer [11 C]-PBR28 to visualize microglial activation. We compared PBR28 SUVR in 10 non-CNS cancer survivors and 10 matched healthy controls. Our data revealed (1) microglial activation was significantly higher in caudate, temporal, and occipital regions in late non-central nervous system/CNS cancer survivors compared to healthy controls; (2) increased neuroinflammation in cancer survivors was not accompanied by significant differences in plasma cytokine markers of peripheral inflammation; (3) increased neuroinflammation was not accompanied by reduced fractional anisotropy, suggesting intact white matter microstructural integrity, a marker of neurovascular fiber tract organization; and (4) the presentation of chronic systemic symptoms in cancer survivors was significantly connected with microglial activation. We present the first data empirically supporting the concept of a peripheral-to-centralized inflammatory response in non-CNS cancer survivors, specifically those previously afflicted with head and neck cancer. Following resolution of the initial peripheral inflammation from the cancer/its treatments, in some cases damage/toxification to the central nervous system occurs, ensuing chronic systemic symptoms.
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Affiliation(s)
- Poppy L. A. Schoenberg
- Department of Physical Medicine and RehabilitationVanderbilt University Medical CenterNashvilleTennesseeUSA
- Osher Center for Integrative HealthVanderbilt University Medical CenterNashvilleTennesseeUSA
| | - Alexander K. Song
- Department of NeurologyVanderbilt University Medical CenterNashvilleTennesseeUSA
- Vanderbilt Brain InstituteVanderbilt UniversityNashvilleTennesseeUSA
| | - Emily M. Mohr
- Osher Center for Integrative HealthVanderbilt University Medical CenterNashvilleTennesseeUSA
| | - Baxter P. Rogers
- Vanderbilt Brain InstituteVanderbilt UniversityNashvilleTennesseeUSA
- Department of Radiology and Radiological SciencesVanderbilt University Medical CenterNashvilleTennesseeUSA
| | - Todd E. Peterson
- Vanderbilt Brain InstituteVanderbilt UniversityNashvilleTennesseeUSA
- Department of Radiology and Radiological SciencesVanderbilt University Medical CenterNashvilleTennesseeUSA
| | - Barbara A. Murphy
- Division of Hematology and OncologyVanderbilt‐Ingram Cancer CenterNashvilleTennesseeUSA
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9
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Yu C, Deng XJ, Xu D. Microglia in epilepsy. Neurobiol Dis 2023; 185:106249. [PMID: 37536386 DOI: 10.1016/j.nbd.2023.106249] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/07/2023] [Accepted: 07/31/2023] [Indexed: 08/05/2023] Open
Abstract
Epilepsy is one of most common chronic neurological disorders, and the antiseizure medications developed by targeting neurocentric mechanisms have not effectively reduced the proportion of patients with drug-resistant epilepsy. Further exploration of the cellular or molecular mechanism of epilepsy is expected to provide new options for treatment. Recently, more and more researches focus on brain network components other than neurons, among which microglia have attracted much attention for their diverse biological functions. As the resident immune cells of the central nervous system, microglia have highly plastic transcription, morphology and functional characteristics, which can change dynamically in a context-dependent manner during the progression of epilepsy. In the pathogenesis of epilepsy, highly reactive microglia interact with other components in the epileptogenic network by performing crucial functions such as secretion of soluble factors and phagocytosis, thus continuously reshaping the landscape of the epileptic brain microenvironment. Indeed, microglia appear to be both pro-epileptic and anti-epileptic under the different spatiotemporal contexts of disease, rendering interventions targeting microglia biologically complex and challenging. This comprehensive review critically summarizes the pathophysiological role of microglia in epileptic brain homeostasis alterations and explores potential therapeutic or modulatory targets for epilepsy targeting microglia.
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Affiliation(s)
- Cheng Yu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China
| | - Xue-Jun Deng
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China
| | - Da Xu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China.
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10
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Peyronneau MA, Kuhnast B, Nguyen DL, Jego B, Sayet G, Caillé F, Lavisse S, Gervais P, Stankoff B, Sarazin M, Remy P, Bouilleret V, Leroy C, Bottlaender M. [ 18F]DPA-714: Effect of co-medications, age, sex, BMI and TSPO polymorphism on the human plasma input function. Eur J Nucl Med Mol Imaging 2023; 50:3251-3264. [PMID: 37291448 DOI: 10.1007/s00259-023-06286-1] [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: 12/06/2022] [Accepted: 05/16/2023] [Indexed: 06/10/2023]
Abstract
PURPOSE We aimed to assess the effect of concomitant medication, age, sex, body mass index and 18-kDa translocator protein (TSPO) binding affinity status on the metabolism and plasma pharmacokinetics of [18F]DPA-714 and their influence on the plasma input function in a large cohort of 201 subjects who underwent brain and whole-body PET imaging to investigate the role of neuroinflammation in neurological diseases. METHODS The non-metabolized fraction of [18F]DPA-714 was estimated in venous plasma of 138 patients and 63 healthy controls (HCs; including additional arterial sampling in 16 subjects) during the 90 min brain PET acquisition using a direct solid-phase extraction method. The mean fraction between 70 and 90 min post-injection ([18F]DPA-71470-90) and corresponding normalized plasma concentration (SUV70-90) were correlated with all factors using a multiple linear regression model. Differences between groups (arterial vs venous measurements; HCs vs patients; high- (HAB), mixed- (MAB) and low-affinity binders (LAB); subjects with vs without co-medications, females vs males were also assessed using the non-parametric Mann-Whitney or Kruskal-Wallis ANOVA tests. Finally, the impact of co-medications on the brain uptake of [18F]DPA-714 at equilibrium was investigated. RESULTS As no significant differences were observed between arterial and venous [18F]DPA-71470-90 and SUV70-90, venous plasma was used for correlations. [18F]DPA-71470-90 was not significantly different between patients and HCS (59.7 ± 12.3% vs 60.2 ± 12.9%) despite high interindividual variability. However, 47 subjects exhibiting a huge increase or decrease of [18F]DPA-71470-90 (up to 88% or down to 23%) and SUV70-90 values (2-threefold) were found to receive co-medications identified as inhibitors or inducers of CYP3A4, known to catalyse [18F]DPA-714 metabolism. Comparison between cortex-to-plasma ratios using individual input function (VTIND) or population-based input function derived from untreated HCs (VTPBIF) indicated that non-considering the individual metabolism rate led to a bias of about 30% in VT values. Multiple linear regression model analysis of subjects free of these co-medications suggested significant correlations between [18F]DPA-71470-90 and age, BMI and sex while TSPO polymorphism did not influence the metabolism of the radiotracer. [18F]DPA-714 metabolism fell with age and BMI and was significantly faster in females than in males. Whole-body PET/CT exhibited a high uptake of the tracer in TSPO-rich organs (heart wall, spleen, kidneys…) and those involved in metabolism and excretion pathways (liver, gallbladder) in HAB and MAB with a strong decrease in LAB (-89% and -85%) resulting in tracer accumulation in plasma (4.5 and 3.3-fold increase). CONCLUSION Any co-medication that inhibits or induces CYP3A4 as well as TSPO genetic status, age, BMI and sex mostly contribute to interindividual variations of the radiotracer metabolism and/or concentration that may affect the input function of [18F]DPA-714 and consequently its human brain and peripheral uptake. TRIAL REGISTRATION INFLAPARK, NCT02319382, registered December 18, 2014, retrospectively registered; IMABIO 3, NCT01775696, registered January 25, 2013, retrospectively registered; INFLASEP, NCT02305264, registered December 2, 2014, retrospectively registered; EPI-TEP, EudraCT 2017-003381-27, registered September 24, 2018.
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Affiliation(s)
- M A Peyronneau
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France.
| | - B Kuhnast
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
| | - D-L Nguyen
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
| | - B Jego
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
| | - G Sayet
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
| | - F Caillé
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
| | - S Lavisse
- Laboratoire Des Maladies Neurodégénératives, Université Paris-Saclay, CEA, CNRS, MIRCen, F-92265, Fontenay-Aux-Roses, France
| | - P Gervais
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
| | - B Stankoff
- Sorbonne Université, UPMC Paris 06, Institut du Cerveau et de La Moelle Epinière, Hôpital de La Pitié Salpêtrière, Inserm UMR S 1127, CNRS UMR 7225, Paris, France
| | - M Sarazin
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
- Service de Neurologie de La Mémoire Et du Langage, GHU Paris Psychiatrie & Neurosciences, Hôpital Sainte Anne, F-75014, Paris, France
| | - P Remy
- Laboratoire Des Maladies Neurodégénératives, Université Paris-Saclay, CEA, CNRS, MIRCen, F-92265, Fontenay-Aux-Roses, France
- Centre Expert Parkinson, Neurologie, Hôpital Henri Mondor, AP-HP, F-94010, Créteil, France
- Université Paris-Est Créteil, INSERM U955, Institut Mondor de Recherche Biomédicale, Equipe NeuroPsychologie Interventionnelle, F-94010, Créteil, France
- Département d'Etudes Cognitives, École Normale Supérieure, Université PSL, F-75005, Paris, France
| | - V Bouilleret
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
- Service de Neurophysiologie Clinique et d'Epileptologie, Hôpital Bicêtre, AP-HP, Université Paris Saclay, F-94270, Le Kremlin-Bicêtre, France
| | - C Leroy
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
| | - M Bottlaender
- Université Paris Saclay, INSERM, CNRS, CEA, Laboratoire d'Imagerie Biomedicale Multimodale (BioMaps), Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, F-91401, ORSAY, France
- Université Paris Saclay, UNIACT, Neurospin, CEA, Gif-Sur-Yvette, F-91190, France
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11
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Jiang A, Handley RR, Lehnert K, Snell RG. From Pathogenesis to Therapeutics: A Review of 150 Years of Huntington's Disease Research. Int J Mol Sci 2023; 24:13021. [PMID: 37629202 PMCID: PMC10455900 DOI: 10.3390/ijms241613021] [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: 07/28/2023] [Revised: 08/15/2023] [Accepted: 08/18/2023] [Indexed: 08/27/2023] Open
Abstract
Huntington's disease (HD) is a debilitating neurodegenerative genetic disorder caused by an expanded polyglutamine-coding (CAG) trinucleotide repeat in the huntingtin (HTT) gene. HD behaves as a highly penetrant dominant disorder likely acting through a toxic gain of function by the mutant huntingtin protein. Widespread cellular degeneration of the medium spiny neurons of the caudate nucleus and putamen are responsible for the onset of symptomology that encompasses motor, cognitive, and behavioural abnormalities. Over the past 150 years of HD research since George Huntington published his description, a plethora of pathogenic mechanisms have been proposed with key themes including excitotoxicity, dopaminergic imbalance, mitochondrial dysfunction, metabolic defects, disruption of proteostasis, transcriptional dysregulation, and neuroinflammation. Despite the identification and characterisation of the causative gene and mutation and significant advances in our understanding of the cellular pathology in recent years, a disease-modifying intervention has not yet been clinically approved. This review includes an overview of Huntington's disease, from its genetic aetiology to clinical presentation and its pathogenic manifestation. An updated view of molecular mechanisms and the latest therapeutic developments will also be discussed.
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Affiliation(s)
- Andrew Jiang
- Applied Translational Genetics Group, Centre for Brain Research, School of Biological Sciences, The University of Auckland, Auckland 1010, New Zealand; (R.R.H.); (K.L.); (R.G.S.)
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12
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Yan X, Siméon FG, Liow JS, Morse CL, Montero Santamaria JA, Jenkins M, Manly LS, Van Buskirk M, Zoghbi SS, Pike VW, Innis RB, Zanotti-Fregonara P. In vivo evaluation of a novel 18F-labeled PET radioligand for translocator protein 18 kDa (TSPO) in monkey brain. Eur J Nucl Med Mol Imaging 2023; 50:2962-2970. [PMID: 37249618 PMCID: PMC10382351 DOI: 10.1007/s00259-023-06270-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 05/18/2023] [Indexed: 05/31/2023]
Abstract
PURPOSE [18F]SF51 was previously found to have high binding affinity and selectivity for 18 kDa translocator protein (TSPO) in mouse brain. This study sought to assess the ability of [18F]SF51 to quantify TSPO in rhesus monkey brain. METHODS Positron emission tomography (PET) imaging was performed in monkey brain (n = 3) at baseline and after pre-blockade with the TSPO ligands PK11195 and PBR28. TSPO binding was calculated as total distribution volume corrected for free parent fraction in plasma (VT/fP) using a two-tissue compartment model. Receptor occupancy and nondisplaceable uptake were determined via Lassen plot. Binding potential (BPND) was calculated as the ratio of specific binding to nondisplaceable uptake. Time stability of VT was used as an indirect probe to detect radiometabolite accumulation in the brain. In vivo and ex vivo experiments were performed in mice to determine the distribution of the radioligand. RESULTS After [18F]SF51 injection, the concentration of brain radioactivity peaked at 2.0 standardized uptake value (SUV) at ~ 10 min and declined to 30% of the peak at 180 min. VT/fP at baseline was generally high (203 ± 15 mL· cm-3) and decreased by ~ 90% after blockade with PK11195. BPND of the whole brain was 7.6 ± 4.3. VT values reached levels similar to terminal 180-min values by 100 min and remained relatively stable thereafter with excellent identifiability (standard errors < 5%), suggesting that no significant radiometabolites accumulated in the brain. Ex vivo experiments in mouse brain showed that 96% of radioactivity was parent. No significant uptake was observed in the skull, suggesting a lack of defluorination in vivo. CONCLUSION The results demonstrate that [18F]SF51 is an excellent radioligand that can quantify TSPO with a good ratio of specific to nondisplaceable uptake and has minimal radiometabolite accumulation in brain. Collectively, the results suggest that [18F]SF51 warrants further evaluation in humans.
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Affiliation(s)
- Xuefeng Yan
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA.
| | - Fabrice G Siméon
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Jeih-San Liow
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Cheryl L Morse
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Jose A Montero Santamaria
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Madeline Jenkins
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Lester S Manly
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Maia Van Buskirk
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Sami S Zoghbi
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Victor W Pike
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Robert B Innis
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Paolo Zanotti-Fregonara
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
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13
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Park J, Wasim S, Jung JH, Kim MH, Lee BC, Alam MM, Lee SY. Synthesis, In Silico and In Vitro Characterization of Novel N, N-Substituted Pyrazolopyrimidine Acetamide Derivatives for the 18KDa Translocator Protein (TSPO). Pharmaceuticals (Basel) 2023; 16:ph16040576. [PMID: 37111333 PMCID: PMC10142799 DOI: 10.3390/ph16040576] [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: 02/08/2023] [Revised: 04/01/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
The translocator protein (TSPO) is an interesting biological target for molecular imaging and therapy because the overexpression of TSPO is associated with microglial activation caused by neuronal damage or neuroinflammation, and these activated microglia are involved in various central nervous system (CNS) diseases. The TSPO is a target for neuroprotective treatment, which is used with the aim of reducing microglial cell activation. The novel N,N-disubstituted pyrazolopyrimidine acetamides scaffold (GMA 7-17), which bears a fluorine atom and is directly linked to the phenyl moiety, was synthesized, and each of the novel ligands was characterized in vitro. All of the newly synthesized ligands displayed picomolar to nanomolar affinity for the TSPO. Particularly, an in vitro affinity study led to the discovery of 2-(5,7-diethyl-2-(4-fluorophenyl)pyrazolo [1,5-a]pyrimidin-3-yl)-N-ethyl-N-phenylacetamide GMA 15 (Ki = 60 pM), a novel TSPO ligand that exhibits a 61-fold enhancement in affinity compared to the reference standard DPA-714 (Ki = 3.66 nM). Molecular dynamic (MD) studies of the highest affinity binder, GMA 15, were carried out to check its time-dependent stability with the receptor compared to DPA-714 and PK11195. The hydrogen bond plot also indicated that GMA 15 formed higher hydrogen bonds compared to DPA-714 and PK11195. We anticipate that further optimization to enhance the potency in a cellular assay needs to be followed, but our strategy of identifying potential TSPO binding novel scaffolds may open up a new avenue to develop novel TSPO ligands suited for potential molecular imaging and a wide range of therapeutic applications.
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Affiliation(s)
- Jaekyung Park
- Gachon Advanced Institute for Health Science and Technology, Graduate School, Gachon University, Incheon 21999, Republic of Korea
| | - Sobia Wasim
- Department of Biochemistry, College of Medicine, Gachon University, Incheon 21999, Republic of Korea
| | - Jae Ho Jung
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea
| | - Mi-Hyun Kim
- Gachon Institute of Pharmaceutical Science and Department of Pharmacy, College of Pharmacy, Gachon University, Incheon 21936, Republic of Korea
| | - Byung Chul Lee
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea
- Center for Nanomolecular Imaging and Innovative Drug Development, Advanced Institutes of Convergence Technology, Suwon 16229, Republic of Korea
| | | | - Sang-Yoon Lee
- Gachon Advanced Institute for Health Science and Technology, Graduate School, Gachon University, Incheon 21999, Republic of Korea
- Neuroscience Research Institute, Gachon University, Incheon 20565, Republic of Korea
- Department of Neuroscience, College of Medicine, Gachon University, Incheon 21936, Republic of Korea
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14
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Roussakis AA, Gennaro M, Gordon MF, Reilmann R, Borowsky B, Rynkowski G, Lao-Kaim NP, Papoutsou Z, Savola JM, Hayden MR, Owen DR, Kalk N, Lingford-Hughes A, Gunn RN, Searle G, Tabrizi SJ, Piccini P. A PET-CT study on neuroinflammation in Huntington's disease patients participating in a randomized trial with laquinimod. Brain Commun 2023; 5:fcad084. [PMID: 37020532 PMCID: PMC10069663 DOI: 10.1093/braincomms/fcad084] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 12/19/2022] [Accepted: 03/17/2023] [Indexed: 04/05/2023] Open
Abstract
Microglia activation, an indicator of central nervous system inflammation, is believed to contribute to the pathology of Huntington's disease. Laquinimod is capable of regulating microglia. By targeting the translocator protein, 11C-PBR28 PET-CT imaging can be used to assess the state of regional gliosis in vivo and explore the effects of laquinimod treatment. This study relates to the LEGATO-HD, multi-centre, double-blinded, Phase 2 clinical trial with laquinimod (US National Registration: NCT02215616). Fifteen patients of the UK LEGATO-HD cohort (mean age: 45.2 ± 7.4 years; disease duration: 5.6 ± 3.0 years) were treated with laquinimod (0.5 mg, N = 4; 1.0 mg, N = 6) or placebo (N = 5) daily. All participants had one 11C-PBR28 PET-CT and one brain MRI scan before laquinimod (or placebo) and at the end of treatment (12 months apart). PET imaging data were quantified to produce 11C-PBR28 distribution volume ratios. These ratios were calculated for the caudate and putamen using the reference Logan plot with the corpus callosum as the reference region. Partial volume effect corrections (Müller-Gartner algorithm) were applied. Differences were sought in Unified Huntington's Disease Rating Scale scores and regional distribution volume ratios between baseline and follow-up and between the two treatment groups (laquinimod versus placebo). No significant change in 11C-PBR28 distribution volume ratios was found post treatment in the caudate and putamen for both those treated with laquinimod (N = 10) and those treated with placebo (N = 5). Over time, the patients treated with laquinimod did not show a significant clinical improvement. Data from the 11C-PBR28 PET-CT study indicate that laquinimod may not have affected regional translocator protein expression and clinical performance over the studied period.
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Affiliation(s)
| | - Marta Gennaro
- Brain Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | | | | | | | | | - Nicholas P Lao-Kaim
- Brain Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | - Zoe Papoutsou
- Brain Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | | | - Michael R Hayden
- Centre for Molecular Medicine and Therapeutics, BC Children’s Hospital and Research Institute, University of British Columbia, Vancouver V5Z 4H4, Canada
| | - David R Owen
- Brain Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | - Nicola Kalk
- Brain Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | - Anne Lingford-Hughes
- Brain Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | - Roger N Gunn
- Brain Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
- Invicro, Hammersmith Hospital,, London W12 0NN, UK
| | | | - Sarah J Tabrizi
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Paola Piccini
- Brain Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
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Rodina AV, Semochkina YP, Vysotskaya OV, Parfenova AA, Moskaleva EY. Radiation-induced neuroinflammation monitoring by the level of peripheral blood monocytes with high expression of translocator protein. Int J Radiat Biol 2023; 99:1364-1377. [PMID: 36821843 DOI: 10.1080/09553002.2023.2177765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 01/11/2023] [Accepted: 02/01/2023] [Indexed: 02/25/2023]
Abstract
PURPOSE Currently there are no effective diagnostic methods for the control of neuroinflammation before manifestation of cognitive impairment after head irradiation. The translocator protein (TSPO) is highly expressed in glial cells upon brain damage, therefore we compared the changes in the number of cells with high TSPO expression in the brain and peripheral blood during radiation-induced neuroinflammation. MATERIALS AND METHODS Hippocampal cytokines mRNA expression and the content of cells with high TSPO expression in the brain and peripheral blood monocytes were analyzed up to eight months after mice head γ-irradiation at a dose of 2 Gy or 8Gy. RESULTS Mice irradiation at a dose of 8 Gy causes neuroinflammation, accompanied by an increase of M1 microglia and TSPOhigh cells in the brain, elevated gene expression of pro-inflammatory and decreased of anti-inflammatory cytokines along with an increased number of microglia and astrocytes in the hippocampus. The content of TSPOhigh cells in the brain correlates with the level TSPOhigh monocytes in three days, one month and two months after exposure. CONCLUSIONS An increase in the level of the monocytes with high expression of TSPO may be considered as a marker for an early diagnostics of post-radiation brain damage leading to cognitive impairment.
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Affiliation(s)
- Alla V Rodina
- Department of Cell Biology, Immunology and Molecular Medicine, Kurchatov Complex of NBICS Technologies, NRC Kurchatov Institute, Moscow, Russian Federation
| | - Yulia P Semochkina
- Department of Cell Biology, Immunology and Molecular Medicine, Kurchatov Complex of NBICS Technologies, NRC Kurchatov Institute, Moscow, Russian Federation
| | - Olga V Vysotskaya
- Department of Cell Biology, Immunology and Molecular Medicine, Kurchatov Complex of NBICS Technologies, NRC Kurchatov Institute, Moscow, Russian Federation
| | - Anna A Parfenova
- Department of Cell Biology, Immunology and Molecular Medicine, Kurchatov Complex of NBICS Technologies, NRC Kurchatov Institute, Moscow, Russian Federation
| | - Elizaveta Y Moskaleva
- Department of Cell Biology, Immunology and Molecular Medicine, Kurchatov Complex of NBICS Technologies, NRC Kurchatov Institute, Moscow, Russian Federation
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16
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Lopresti BJ, Royse SK, Mathis CA, Tollefson SA, Narendran R. Beyond monoamines: I. Novel targets and radiotracers for Positron emission tomography imaging in psychiatric disorders. J Neurochem 2023; 164:364-400. [PMID: 35536762 DOI: 10.1111/jnc.15615] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/05/2022] [Accepted: 04/06/2022] [Indexed: 10/18/2022]
Abstract
With the emergence of positron emission tomography (PET) in the late 1970s, psychiatry had access to a tool capable of non-invasive assessment of human brain function. Early applications in psychiatry focused on identifying characteristic brain blood flow and metabolic derangements using radiotracers such as [15 O]H2 O and [18 F]FDG. Despite the success of these techniques, it became apparent that more specific probes were needed to understand the neurochemical bases of psychiatric disorders. The first neurochemical PET imaging probes targeted sites of action of neuroleptic (dopamine D2 receptors) and psychoactive (serotonin receptors) drugs. Based on the centrality of monoamine dysfunction in psychiatric disorders and the measured success of monoamine-enhancing drugs in treating them, the next 30 years witnessed the development of an armamentarium of PET radiopharmaceuticals and imaging methodologies for studying monoamines. Continued development of monoamine-enhancing drugs over this time however was less successful, realizing only modest gains in efficacy and tolerability. As patent protection for many widely prescribed and profitable psychiatric drugs lapsed, drug development pipelines shifted away from monoamines in search of novel targets with the promises of improved efficacy, or abandoned altogether. Over this period, PET radiopharmaceutical development activities closely paralleled drug development priorities resulting in the development of new PET imaging agents for non-monoamine targets. Part one of this review will briefly survey novel PET imaging targets with relevance to the field of psychiatry, which include the metabotropic glutamate receptor type 5 (mGluR5), purinergic P2 X7 receptor, type 1 cannabinoid receptor (CB1 ), phosphodiesterase 10A (PDE10A), and describe radiotracers developed for these and other targets that have matured to human subject investigations. Current limitations of the targets and techniques will also be discussed.
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Affiliation(s)
- Brian J Lopresti
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sarah K Royse
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Chester A Mathis
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Savannah A Tollefson
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Rajesh Narendran
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Departments of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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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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18
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Kim J, Kim YK. Molecular Imaging of Neuroinflammation in Alzheimer's Disease and Mild Cognitive Impairment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1411:301-326. [PMID: 36949316 DOI: 10.1007/978-981-19-7376-5_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/24/2023]
Abstract
Alzheimer's disease (AD) is the most prevalent neurocognitive disorder. Due to the ineffectiveness of treatments targeting the amyloid cascade, molecular biomarkers for neuroinflammation are attracting attention with increasing knowledge about the role of neuroinflammation in the pathogenesis of AD. This chapter will explore the results of studies using molecular imaging for diagnosing AD and mild cognitive impairment (MCI). Because it is critical to interpreting the data to understand which substances are targeted in molecular imaging, this chapter will discuss the two most significant targets, microglia and astrocytes, as well as the best-known radioligands for each. Then, neuroimaging results with PET neuroinflammation imaging will be reviewed for AD and MCI. Although a growing body of evidence has suggested that these molecular imaging biomarkers for neuroinflammation may have a role in the diagnosis of AD and MCI, the findings are inconsistent or cross-sectional, which indicates that it is difficult to apply the contents in practice due to the need for additional study. In particular, because the results of multiple interventions targeting neuroinflammation were inconclusive, molecular imaging markers for neuroinflammation can be used in combination with conventional markers to select appropriate patients for early intervention for neuroinflammation rather than as a single marker.
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Affiliation(s)
- Junhyung Kim
- Department of Psychiatry, Korea University College of Medicine, Korea University Guro Hospital, Seoul, Republic of Korea
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Yong-Ku Kim
- Department of Psychiatry, Korea University Ansan Hospital, Ansan, Republic of Korea.
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19
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Eggerstorfer B, Kim JH, Cumming P, Lanzenberger R, Gryglewski G. Meta-analysis of molecular imaging of translocator protein in major depression. Front Mol Neurosci 2022; 15:981442. [PMID: 36226319 PMCID: PMC9549359 DOI: 10.3389/fnmol.2022.981442] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 09/01/2022] [Indexed: 11/13/2022] Open
Abstract
Molecular neuroimaging studies provide mounting evidence that neuroinflammation plays a contributory role in the pathogenesis of major depressive disorder (MDD). This has been the focus of a number of positron emission tomography (PET) studies of the 17-kDa translocator protein (TSPO), which is expressed by microglia and serves as a marker of neuroinflammation. In this meta-analysis, we compiled and analyzed all available molecular imaging studies comparing cerebral TSPO binding in MDD patients with healthy controls. Our systematic literature search yielded eight PET studies encompassing 238 MDD patients and 164 healthy subjects. The meta-analysis revealed relatively increased TSPO binding in several cortical regions (anterior cingulate cortex: Hedges’ g = 0.6, 95% CI: 0.36, 0.84; hippocampus: g = 0.54, 95% CI: 0.26, 0.81; insula: g = 0.43, 95% CI: 0.17, 0.69; prefrontal cortex: g = 0.36, 95% CI: 0.14, 0.59; temporal cortex: g = 0.39, 95% CI: –0.04, 0.81). While the high range of effect size in the temporal cortex might reflect group-differences in body mass index (BMI), exploratory analyses failed to reveal any relationship between elevated TSPO availability in the other four brain regions and depression severity, age, BMI, radioligand, or the binding endpoint used, or with treatment status at the time of scanning. Taken together, this meta-analysis indicates a widespread ∼18% increase of TSPO availability in the brain of MDD patients, with effect sizes comparable to those in earlier molecular imaging studies of serotonin transporter availability and monoamine oxidase A binding.
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Affiliation(s)
- Benjamin Eggerstorfer
- Department of Psychiatry and Psychotherapy, Comprehensive Center for Clinical Neurosciences and Mental Health (C3NMH), Medical University of Vienna, Vienna, Austria
| | - Jong-Hoon Kim
- Department of Psychiatry, Gachon University College of Medicine, Gil Medical Center, Neuroscience Research Institute, GAIHST, Gachon University, Incheon, South Korea
| | - Paul Cumming
- Department of Nuclear Medicine, Inselspital, Bern University, Bern, Switzerland
- School of Psychology and Counselling, Queensland University of Technology, Brisbane, QLD, Australia
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Comprehensive Center for Clinical Neurosciences and Mental Health (C3NMH), Medical University of Vienna, Vienna, Austria
- *Correspondence: Rupert Lanzenberger,
| | - Gregor Gryglewski
- Department of Psychiatry and Psychotherapy, Comprehensive Center for Clinical Neurosciences and Mental Health (C3NMH), Medical University of Vienna, Vienna, Austria
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20
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Huang J. Novel brain PET imaging agents: Strategies for imaging neuroinflammation in Alzheimer’s disease and mild cognitive impairment. Front Immunol 2022; 13:1010946. [PMID: 36211392 PMCID: PMC9537554 DOI: 10.3389/fimmu.2022.1010946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/06/2022] [Indexed: 11/25/2022] Open
Abstract
Alzheimer’s disease (AD) is a devastating neurodegenerative disease with a concealed onset and continuous deterioration. Mild cognitive impairment (MCI) is the prodromal stage of AD. Molecule-based imaging with positron emission tomography (PET) is critical in tracking pathophysiological changes among AD and MCI patients. PET with novel targets is a promising approach for diagnostic imaging, particularly in AD patients. Our present review overviews the current status and applications of in vivo molecular imaging toward neuroinflammation. Although radiotracers can remarkably diagnose AD and MCI patients, a variety of limitations prevent the recommendation of a single technique. Recent studies examining neuroinflammation PET imaging suggest an alternative approach to evaluate disease progression. This review concludes that PET imaging towards neuroinflammation is considered a promising approach to deciphering the enigma of the pathophysiological process of AD and MCI.
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21
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Pike CK, Kim M, Schnitzer K, Mercaldo N, Edwards R, Napadow V, Zhang Y, Morrissey EJ, Alshelh Z, Evins AE, Loggia ML, Gilman JM. Study protocol for a phase II, double-blind, randomised controlled trial of cannabidiol (CBD) compared with placebo for reduction of brain neuroinflammation in adults with chronic low back pain. BMJ Open 2022; 12:e063613. [PMID: 36123113 PMCID: PMC9486315 DOI: 10.1136/bmjopen-2022-063613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
INTRODUCTION Chronic pain is a debilitating medical problem that is difficult to treat. Neuroinflammatory pathways have emerged as a potential therapeutic target, as preclinical studies have demonstrated that glial cells and neuroglial interactions play a role in the establishment and maintenance of pain. Recently, we used positron emission tomography (PET) to demonstrate increased levels of 18 kDa translocator protein (TSPO) binding, a marker of glial activation, in patients with chronic low back pain (cLBP). Cannabidiol (CBD) is a glial inhibitor in animal models, but studies have not assessed whether CBD reduces neuroinflammation in humans. The principal aim of this trial is to evaluate whether CBD, compared with placebo, affects neuroinflammation, as measured by TSPO levels. METHODS AND ANALYSIS This is a double-blind, randomised, placebo-controlled, phase II clinical trial. Eighty adults (aged 18-75) with cLBP for >6 months will be randomised to either an FDA-approved CBD medication (Epidiolex) or matching placebo for 4 weeks using a dose-escalation design. All participants will undergo integrated PET/MRI at baseline and after 4 weeks of treatment to evaluate neuroinflammation using [11C]PBR28, a second-generation radioligand for TSPO. Our primary hypothesis is that participants randomised to CBD will demonstrate larger reductions in thalamic [11C]PBR28 signal compared with those receiving placebo. We will also assess the effect of CBD on (1) [11C]PBR28 signal from limbic regions, which our prior work has linked to depressive symptoms and (2) striatal activation in response to a reward task. Additionally, we will evaluate self-report measures of cLBP intensity and bothersomeness, depression and quality of life at baseline and 4 weeks. ETHICS AND DISSEMINATION This protocol is approved by the Massachusetts General Brigham Human Research Committee (protocol number: 2021P002617) and FDA (IND number: 143861) and registered with ClinicalTrials.gov. Results will be published in peer-reviewed journals and presented at conferences. TRIAL REGISTRATION NUMBER NCT05066308; ClinicalTrials.gov.
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Affiliation(s)
- Chelsea K Pike
- Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA
- Massachusetts General Hospital Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
| | - Minhae Kim
- Massachusetts General Hospital Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
| | - Kristina Schnitzer
- Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA
| | - Nathaniel Mercaldo
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Robert Edwards
- Department of Anesthesiology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Vitaly Napadow
- Massachusetts General Hospital Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
- Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Charlestown, Massachusetts, USA
| | - Yi Zhang
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Erin Janas Morrissey
- Massachusetts General Hospital Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
| | - Zeynab Alshelh
- Massachusetts General Hospital Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| | - A Eden Evins
- Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA
| | - Marco L Loggia
- Massachusetts General Hospital Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Jodi M Gilman
- Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA
- Massachusetts General Hospital Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, USA
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA
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22
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Viviano M, Barresi E, Siméon FG, Costa B, Taliani S, Da Settimo F, Pike VW, Castellano S. Essential Principles and Recent Progress in the Development of TSPO PET Ligands for Neuroinflammation Imaging. Curr Med Chem 2022; 29:4862-4890. [PMID: 35352645 PMCID: PMC10080361 DOI: 10.2174/0929867329666220329204054] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 12/21/2021] [Accepted: 01/25/2022] [Indexed: 11/22/2022]
Abstract
The translocator protein 18kDa (TSPO) is expressed in the outer mitochondrial membrane and is implicated in several functions, including cholesterol transport and steroidogenesis. Under normal physiological conditions, TSPO is present in very low concentrations in the human brain but is markedly upregulated in response to brain injury and inflammation. This upregulation is strongly associated with activated microglia. Therefore, TSPO is particularly suited for assessing active gliosis associated with brain lesions following injury or disease. For over three decades, TSPO has been studied as a biomarker. Numerous radioligands for positron emission tomography (PET) that target TSPO have been developed for imaging inflammatory progression in the brain. Although [11C]PK11195, the prototypical first-generation PET radioligand, is still widely used for in vivo studies, mainly now as its single more potent R-enantiomer, it has severe limitations, including low sensitivity and poor amenability to quantification. Second-generation radioligands are characterized by higher TSPO specific signals but suffer from other drawbacks, such as sensitivity to the TSPO single nucleotide polymorphism (SNP) rs6971. Therefore, their applications in human studies have the burden of needing to genotype subjects. Consequently, recent efforts are focused on developing improved radioligands that combine the optimal features of the second generation with the ability to overcome the differences in binding affinities across the population. This review presents essential principles in the design and development of TSPO PET ligands and discusses prominent examples among the main chemotypes.
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Affiliation(s)
- Monica Viviano
- Department of Pharmacy, University of Salerno, 84084 Fisciano (SA), Italy
| | | | - Fabrice G. Siméon
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Barbara Costa
- Department of Pharmacy, University of Pisa, 56126, Pisa, Italy
| | - Sabrina Taliani
- Department of Pharmacy, University of Pisa, 56126, Pisa, Italy
| | | | - Victor W. Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sabrina Castellano
- Department of Pharmacy, University of Salerno, 84084 Fisciano (SA), Italy
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23
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Masdeu JC, Pascual B, Fujita M. Imaging Neuroinflammation in Neurodegenerative Disorders. J Nucl Med 2022; 63:45S-52S. [PMID: 35649654 DOI: 10.2967/jnumed.121.263200] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 05/03/2022] [Indexed: 02/07/2023] Open
Abstract
Neuroinflammation plays a major role in the etiopathology of neurodegenerative diseases, including Alzheimer and Parkinson diseases, frontotemporal lobar degeneration, and amyotrophic lateral sclerosis. In vivo monitoring of neuroinflammation using PET is critical to understand this process, and data are accumulating in this regard, thus a review is useful. From PubMed, we retrieved publications using any of the available PET tracers to image neuroinflammation in humans as well as selected articles dealing with experimental animal models or the chemistry of currently used or potential radiotracers. We reviewed 280 articles. The most common PET neuroinflammation target, translocator protein (TSPO), has limitations, lacking cellular specificity and the ability to separate neuroprotective from neurotoxic inflammation. However, TSPO PET is useful to define the amount and location of inflammation in the brain of people with neurodegenerative disorders. We describe the characteristics of TSPO and other potential PET neuroinflammation targets and PET tracers available or in development. Despite target and tracer limitations, in recent years there has been a sharp increase in the number of reports of neuroinflammation PET in humans. The most studied has been Alzheimer disease, in which neuroinflammation seems initially neuroprotective and neurotoxic later in the progression of the disease. We describe the findings in all the major neurodegenerative disorders. Neuroinflammation PET is an indispensable tool to understand the process of neurodegeneration, particularly in humans, as well as to validate target engagement in therapeutic clinical trials.
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Affiliation(s)
- Joseph C Masdeu
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Neurological Institute, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, Texas; and
| | - Belen Pascual
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Neurological Institute, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, Texas; and
| | - Masahiro Fujita
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Neurological Institute, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, Texas; and.,PET Core, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, Texas
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24
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Adhikari A, Pandey A, Kumar D, Tiwari AK. Determination of Hybrid TSPO Ligands with Minimal Impact of SNP
(rs6971) through Molecular Docking and MD Simulation Study. LETT DRUG DES DISCOV 2022. [DOI: 10.2174/1570180818666210413130326] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
In an endeavor to ascertain high-affinity TSPO ligands with minimal single
nucleotide polymorphism (SNP), six hybrid molecules have been identified as new leads for future
inflammation PET imaging.
Objective:
Genesis for chemical design was encouraged from structural families of well-known ligands
FEBMP and PBR28/ DAA1106 that have demonstrated remarkable TSPO binding characteristics.
Methods:
All proposed hybrid ligands 1-6 are subjected to molecular docking and simulation studies
with wild and mutant protein to study their interactions, binding, consistency of active conformations
and are correlated with well-established TSPO ligands.
Results:
Each hybrid ligand demonstrate better docking score > -11.00 kcal/mol with TSPO with
respect to gold standard PK11195, i.e., -11.00 kcal/mol for 4UC3 and -12.94 kcal/mol for 4UC1. On
comparison with FEBMP and GE-180 (-12.57, -7.24 kcal/mol for 4UC3 and -14.10, -11.32
kcal/mol for 4UC1), ligand 3 demonstrates maximum docking energy (> -15.50 kcal/mol) with
minimum SNP (0.26 kcal/mol).
Discussion:
Presence of strong hydrogen bond Arg148-3.27Å (4UC1) and Trp50-2.43Å, Asp28-
2.57Å (4UC3) apart from short-range interactions, including π–π interactions with the aromatic residues,
such as (Trp39, Phe46, Trp135) and (Trp39, Trp108), attributes towards its strong binding.
Conclusion:
Utilizing the results of binding energy, we concluded stable complex formation of these
hybrid ligands that could bind to TSPO with the least effect of SNP with similar interactions to
known ligands. Overall, ligand 3 stands out as the best ligand having insignificant deviations per
residue of protein that can be further explored and assessed in detail for future inflammation PET
application after subsequent detailed biological evaluation.
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Affiliation(s)
- Anupriya Adhikari
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| | - Anwesh Pandey
- Department of
Physics, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| | - Devesh Kumar
- Department of
Physics, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| | - Anjani K. Tiwari
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
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25
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Singh P, Adhikari A, Singh D, Gond C, Tiwari AK. The 18-kDa Translocator Protein PET Tracers as a Diagnostic Marker for Neuroinflammation: Development and Current Standing. ACS OMEGA 2022; 7:14412-14429. [PMID: 35557664 PMCID: PMC9089361 DOI: 10.1021/acsomega.2c00588] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 04/05/2022] [Indexed: 05/13/2023]
Abstract
Translocator protein (TSPO, 18 kDa) is an evolutionary, well-preserved, and tryptophan-rich 169-amino-acid protein which localizes on the contact sites between the outer and inner mitochondrial membranes of steroid-synthesizing cells. This mitochondrial protein is implicated in an extensive range of cellular activities, including steroid synthesis, cholesterol transport, apoptosis, mitochondrial respiration, and cell proliferation. The upregulation of TSPO is well documented in diverse disease conditions including neuroinflammation, cancer, brain injury, and inflammation in peripheral organs. On the basis of these outcomes, TSPO has been assumed to be a fascinating subcellular target for early stage imaging of the diseased state and for therapeutic purposes. The main outline of this Review is to give an update on dealing with the advances made in TSPO PET tracers for neuroinflammation, synchronously emphasizing the approaches applied for the design and advancement of new tracers with reference to their structure-activity relationship (SAR).
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Affiliation(s)
- Priya Singh
- Department
of Chemistry, Babasaheb Bhimrao Ambedkar
University (A Central University), Lucknow, 226025, Uttar Pradesh, India
| | - Anupriya Adhikari
- Department
of Chemistry, Babasaheb Bhimrao Ambedkar
University (A Central University), Lucknow, 226025, Uttar Pradesh, India
| | - Deepika Singh
- Department
of Chemistry, Babasaheb Bhimrao Ambedkar
University (A Central University), Lucknow, 226025, Uttar Pradesh, India
| | - Chandraprakash Gond
- Department
of Chemistry, Babasaheb Bhimrao Ambedkar
University (A Central University), Lucknow, 226025, Uttar Pradesh, India
| | - Anjani Kumar Tiwari
- Department
of Chemistry, Babasaheb Bhimrao Ambedkar
University (A Central University), Lucknow, 226025, Uttar Pradesh, India
- Address:
Department of Chemistry,
Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh. Tel.: +91-7503381343. Fax: +91-522-2440821. E-mail:
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26
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Nicotinic Acetylcholine Receptors and Microglia as Therapeutic and Imaging Targets in Alzheimer's Disease. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27092780. [PMID: 35566132 PMCID: PMC9102429 DOI: 10.3390/molecules27092780] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/21/2022] [Accepted: 04/25/2022] [Indexed: 12/12/2022]
Abstract
Amyloid-β (Aβ) accumulation and tauopathy are considered the pathological hallmarks of Alzheimer’s disease (AD), but attenuation in choline signaling, including decreased nicotinic acetylcholine receptors (nAChRs), is evident in the early phase of AD. Currently, there are no drugs that can suppress the progression of AD due to a limited understanding of AD pathophysiology. For this, diagnostic methods that can assess disease progression non-invasively before the onset of AD symptoms are essential, and it would be valuable to incorporate the concept of neurotheranostics, which simultaneously enables diagnosis and treatment. The neuroprotective pathways activated by nAChRs are attractive targets as these receptors may regulate microglial-mediated neuroinflammation. Microglia exhibit both pro- and anti-inflammatory functions that could be modulated to mitigate AD pathogenesis. Currently, single-cell analysis is identifying microglial subpopulations that may have specific functions in different stages of AD pathologies. Thus, the ability to image nAChRs and microglia in AD according to the stage of the disease in the living brain may lead to the development of new diagnostic and therapeutic methods. In this review, we summarize and discuss the recent findings on the nAChRs and microglia, as well as their methods for live imaging in the context of diagnosis, prophylaxis, and therapy for AD.
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27
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Thomas AM, Barkhof F, Bulte JWM. Opportunities for Molecular Imaging in Multiple Sclerosis Management: Linking Probe to Treatment. Radiology 2022; 303:486-497. [PMID: 35471110 PMCID: PMC9131169 DOI: 10.1148/radiol.211252] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Imaging has been a critical component of multiple sclerosis (MS) management for nearly 40 years. The visual information derived from structural MRI, that is, signs of blood-brain barrier disruption, inflammation and demyelination, and brain and spinal cord atrophy, are the primary metrics used to evaluate therapeutic efficacy in MS. The development of targeted imaging probes has expanded our ability to evaluate and monitor MS and its therapies at the molecular level. Most molecular imaging probes evaluated for MS applications are small molecules initially developed for PET, nearly half of which are derived from U.S. Food and Drug Administration-approved drugs and those currently undergoing clinical trials. Superparamagnetic and fluorinated particles have been used for tracking circulating immune cells (in situ labeling) and immunosuppressive or remyelinating therapeutic stem cells (ex vivo labeling) clinically using proton (hydrogen 1 [1H]) and preclinically using fluorine 19 MRI. Translocator protein PET and 1H MR spectroscopy have been demonstrated to complement imaging metrics from structural (gadolinium-enhanced) MRI in nine and six trials for MS disease-modifying therapies, respectively. Still, despite multiple demonstrations of the utility of molecular imaging probes to evaluate the target location and to elucidate the mechanisms of disease-modifying therapies for MS applications, their use has been sparse in both preclinical and clinical settings.
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Affiliation(s)
- Aline M Thomas
- From the Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, and the Cellular Imaging Section and Vascular Biology Program, Institute for Cell Engineering, the Johns Hopkins University School of Medicine, 733 N Broadway, Room 659, Baltimore, MD 21205 (A.M.T., J.W.M.B.); and Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, the Netherlands (F.B.)
| | - Frederik Barkhof
- From the Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, and the Cellular Imaging Section and Vascular Biology Program, Institute for Cell Engineering, the Johns Hopkins University School of Medicine, 733 N Broadway, Room 659, Baltimore, MD 21205 (A.M.T., J.W.M.B.); and Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, the Netherlands (F.B.)
| | - Jeff W M Bulte
- From the Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, and the Cellular Imaging Section and Vascular Biology Program, Institute for Cell Engineering, the Johns Hopkins University School of Medicine, 733 N Broadway, Room 659, Baltimore, MD 21205 (A.M.T., J.W.M.B.); and Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, the Netherlands (F.B.)
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28
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Gulhane AV, Chen DL. Overview of positron emission tomography in functional imaging of the lungs for diffuse lung diseases. Br J Radiol 2022; 95:20210824. [PMID: 34752146 PMCID: PMC9153708 DOI: 10.1259/bjr.20210824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Positron emission tomography (PET) is a quantitative molecular imaging modality increasingly used to study pulmonary disease processes and drug effects on those processes. The wide range of drugs and other entities that can be radiolabeled to study molecularly targeted processes is a major strength of PET, thus providing a noninvasive approach for obtaining molecular phenotyping information. The use of PET to monitor disease progression and treatment outcomes in DLD has been limited in clinical practice, with most of such applications occurring in the context of research investigations under clinical trials. Given the high costs and failure rates for lung drug development efforts, molecular imaging lung biomarkers are needed not only to aid these efforts but also to improve clinical characterization of these diseases beyond canonical anatomic classifications based on computed tomography. The purpose of this review article is to provide an overview of PET applications in characterizing lung disease, focusing on novel tracers that are in clinical development for DLD molecular phenotyping, and briefly address considerations for accurately quantifying lung PET signals.
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Affiliation(s)
- Avanti V Gulhane
- Department of Radiology, University of Washington School of Medicine, Seattle, United States
| | - Delphine L Chen
- Department of Radiology, University of Washington School of Medicine, Seattle, United States
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29
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Kumari N, Kaul A, Deepika, Srivastava K, Mishra G, Bhagat S, Singh VK, KumarTiwari A. [99mTc-BBPA]: A possible SPECT agent to understand role of 18-kDa translocator protein (PBR/TSPO) during neuro-glial interaction. Bioorg Chem 2022; 121:105678. [DOI: 10.1016/j.bioorg.2022.105678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 11/11/2021] [Accepted: 02/08/2022] [Indexed: 11/02/2022]
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30
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Jia H, Xie T. Tracers progress for positron emission tomography imaging of glial-related disease. J Biomed Res 2022; 36:321-335. [PMID: 36131689 PMCID: PMC9548440 DOI: 10.7555/jbr.36.20220017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Glial cells play an essential part in the neuron system. They can not only serve as structural blocks in the human brain but also participate in many biological processes. Extensive studies have shown that astrocytes and microglia play an important role in neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, as well as glioma, epilepsy, ischemic stroke, and infections. Positron emission tomography is a functional imaging technique providing molecular-level information before anatomic changes are visible and has been widely used in many above-mentioned diseases. In this review, we focus on the positron emission tomography tracers used in pathologies related to glial cells, such as glioma, Alzheimer's disease, and neuroinflammation.
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Affiliation(s)
- Haoran Jia
- Institute of Radiation Medicine, Fudan University, Shanghai 200032, China
| | - Tianwu Xie
- Institute of Radiation Medicine, Fudan University, Shanghai 200032, China
- Tianwu Xie, Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai 200032, China. Tel: +86-21-64048363, E-mail:
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31
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Liu E, Karpf L, Bohl D. Neuroinflammation in Amyotrophic Lateral Sclerosis and Frontotemporal Dementia and the Interest of Induced Pluripotent Stem Cells to Study Immune Cells Interactions With Neurons. Front Mol Neurosci 2022; 14:767041. [PMID: 34970118 PMCID: PMC8712677 DOI: 10.3389/fnmol.2021.767041] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 11/16/2021] [Indexed: 12/14/2022] Open
Abstract
Inflammation is a shared hallmark between amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). For long, studies were conducted on tissues of post-mortem patients and neuroinflammation was thought to be only bystander result of the disease with the immune system reacting to dying neurons. In the last two decades, thanks to improving technologies, the identification of causal genes and the development of new tools and models, the involvement of inflammation has emerged as a potential driver of the diseases and evolved as a new area of intense research. In this review, we present the current knowledge about neuroinflammation in ALS, ALS-FTD, and FTD patients and animal models and we discuss reasons of failures linked to therapeutic trials with immunomodulator drugs. Then we present the induced pluripotent stem cell (iPSC) technology and its interest as a new tool to have a better immunopathological comprehension of both diseases in a human context. The iPSC technology giving the unique opportunity to study cells across differentiation and maturation times, brings the hope to shed light on the different mechanisms linking neurodegeneration and activation of the immune system. Protocols available to differentiate iPSC into different immune cell types are presented. Finally, we discuss the interest in studying monocultures of iPS-derived immune cells, co-cultures with neurons and 3D cultures with different cell types, as more integrated cellular approaches. The hope is that the future work with human iPS-derived cells helps not only to identify disease-specific defects in the different cell types but also to decipher the synergistic effects between neurons and immune cells. These new cellular tools could help to find new therapeutic approaches for all patients with ALS, ALS-FTD, and FTD.
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Affiliation(s)
- Elise Liu
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, INSERM, CNRS, AP-HP, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Léa Karpf
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, INSERM, CNRS, AP-HP, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Delphine Bohl
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, INSERM, CNRS, AP-HP, Hôpital de la Pitié-Salpêtrière, Paris, France
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MacAskill MG, Wimberley C, Morgan TEF, Alcaide-Corral CJ, Newby DE, Lucatelli C, Sutherland A, Pimlott SL, Tavares AAS. Modelling [ 18F]LW223 PET data using simplified imaging protocols for quantification of TSPO expression in the rat heart and brain. Eur J Nucl Med Mol Imaging 2021; 49:137-145. [PMID: 34338808 PMCID: PMC8712302 DOI: 10.1007/s00259-021-05482-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 06/27/2021] [Indexed: 02/07/2023]
Abstract
PURPOSE To provide a comprehensive assessment of the novel 18 kDa translocator protein (TSPO) radiotracer, [18F]LW223, kinetics in the heart and brain when using a simplified imaging approach. METHODS Naive adult rats and rats with surgically induced permanent coronary artery ligation received a bolus intravenous injection of [18F]LW223 followed by 120 min PET scanning with arterial blood sampling throughout. Kinetic modelling of PET data was applied to estimated rate constants, total volume of distribution (VT) and binding potential transfer corrected (BPTC) using arterial or image-derived input function (IDIF). Quantitative bias of simplified protocols using IDIF versus arterial input function (AIF) and stability of kinetic parameters for PET imaging data of different length (40-120 min) were estimated. RESULTS PET outcome measures estimated using IDIF significantly correlated with those derived with invasive AIF, albeit with an inherent systematic bias. Truncation of the dynamic PET scan duration to less than 100 min reduced the stability of the kinetic modelling outputs. Quantification of [18F]LW223 uptake kinetics in the brain and heart required the use of different outcome measures, with BPTC more stable in the heart and VT more stable in the brain. CONCLUSION Modelling of [18F]LW223 PET showed the use of simplified IDIF is acceptable in the rat and the minimum scan duration for quantification of TSPO expression in rats using kinetic modelling with this radiotracer is 100 min. Carefully assessing kinetic outcome measures when conducting a systems level as oppose to single-organ centric analyses is crucial. This should be taken into account when assessing the emerging role of the TSPO heart-brain axis in the field of PET imaging.
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Affiliation(s)
- Mark G MacAskill
- University/ BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK
| | - Catriona Wimberley
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Timaeus E F Morgan
- University/ BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK
| | - Carlos J Alcaide-Corral
- University/ BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK
| | - David E Newby
- University/ BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | | | | | - Sally L Pimlott
- West of Scotland PET Centre, NHS Greater Glasgow and Clyde, Glasgow, UK
| | - Adriana A S Tavares
- University/ BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK.
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK.
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Siméon FG, Lee JH, Morse CL, Stukes I, Zoghbi SS, Manly LS, Liow JS, Gladding RL, Dick RM, Yan X, Taliani S, Costa B, Martini C, Da Settimo F, Castellano S, Innis RB, Pike VW. Synthesis and Screening in Mice of Fluorine-Containing PET Radioligands for TSPO: Discovery of a Promising 18F-Labeled Ligand. J Med Chem 2021; 64:16731-16745. [PMID: 34756026 PMCID: PMC8817670 DOI: 10.1021/acs.jmedchem.1c01562] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Translocator protein 18 kDa (TSPO) is a biomarker of neuroinflammation. [11C]ER176 robustly quantifies TSPO in the human brain with positron emission tomography (PET), irrespective of subject genotype. We aimed to develop an ER176 analog with potential for labeling with longer-lived fluorine-18 (t1/2 = 109.8 min). New fluoro and trifluoromethyl analogs of ER176 were prepared through a concise synthetic strategy. These ligands showed high TSPO affinity and low human genotype sensitivity. Each ligand was initially labeled by a generic 11C-methylation procedure, thereby enabling speedy screening in mice. Each radioligand was rapidly taken up and well retained in the mouse brain at baseline after intravenous injection. Preblocking of TSPO showed that high proportions of brain uptake were specifically bound to TSPO at baseline. Overall, the 3-fluoro analog of [11C]ER176 ([11C]3b) displayed the most promising imaging properties. Therefore, a method was developed to label 3b with [18F]fluoride ion. [18F]3b gave similarly promising PET imaging results and deserves evaluation in higher species.
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Affiliation(s)
- Fabrice G Siméon
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Jae-Hoon Lee
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
- Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 03772, South Korea
| | - Cheryl L Morse
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Ian Stukes
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Sami S Zoghbi
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Lester S Manly
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Jeih-San Liow
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Robert L Gladding
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Rachel M Dick
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Xuefeng Yan
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Sabrina Taliani
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy
| | - Barbara Costa
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy
| | - Claudia Martini
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy
| | | | - Sabrina Castellano
- Department of Pharmacy, University of Salerno, 84084 Fisciano, SA, Italy
| | - Robert B Innis
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Victor W Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
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Rossano SM, Kreisl WC. Untangling the relationship between microglia and tau in Alzheimer's disease. Trends Neurosci 2021; 44:927-929. [PMID: 34674877 DOI: 10.1016/j.tins.2021.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 10/05/2021] [Indexed: 11/15/2022]
Abstract
Autopsy and imaging studies have demonstrated a typical pattern of tau progression in Alzheimer's disease (AD), spreading to previously unaffected regions in an anatomical sequence of 'Braak' stages. In a recent study, Pascoal et al. provide evidence that microgliosis colocalizes with tau in a Braak-like pattern, furthering the notion that microglial activation is strongly related to the propagation of tangle pathology.
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Affiliation(s)
- Samantha M Rossano
- Taub Institute, Columbia University Irving Medical Center, New York, NY, USA
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35
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A pilot [ 11C]PBR28 PET/MRI study of neuroinflammation and neurodegeneration in chronic stroke patients. Brain Behav Immun Health 2021; 17:100336. [PMID: 34589819 PMCID: PMC8474408 DOI: 10.1016/j.bbih.2021.100336] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 08/18/2021] [Accepted: 08/21/2021] [Indexed: 11/24/2022] Open
Abstract
Neuroinflammation occurs in response to acute ischemic stroke, and has been speculated to underlie secondary poststroke pathologies, such as depression, that often develop over time poststroke. However, no study has examined whether neuroinflammation is present in chronic stroke patients (e.g., ≥ 1 year poststroke). This study tested whether neuroinflammation is present in chronic stroke patients, and is associated with neurodegeneration, using [11C]PBR28 PET and diffusion MRI. Eight patients with middle cerebral artery (MCA) ischemic stroke incurred 1–3 years prior and 16 healthy controls underwent [11C]PBR28 PET to measure glial activation and diffusion MRI to measure microstructural integrity by mean diffusivity (MD) and fractional anisotropy (FA) using an integrated PET/MRI scanner. Group differences in [11C]PBR28 binding, MD and FA were analyzed voxelwise across the whole brain excluding the infarct zone defined as voxels containing the infarct in any patient. Compared to controls, patients showed elevations in [11C]PBR28 binding in several brain regions outside the infarct zone, including regions with presumed direct neuroanatomical connections to the infarct (e.g., ipsilesional internal capsule and thalamus) and those without known direct connections (e.g., contralesional thalamus and cingulate gyrus). Patients also showed widespread elevations in MD, with a subset of these regions having reduced FA. In patients, MD was more elevated in regions with co-localized elevations in [11C]PBR28 binding than in contralateral regions without elevations in [11C]PBR28 binding. This pilot study supports the presence of extensive glial activation along with widespread loss in microstructural integrity in non-infarcted tissue in a cohort of patients with chronic MCA stroke. The loss in microstructural integrity was greater in regions with co-localized glial activation. It is possible that stroke risk factors (e.g., hypertension) contributed to these tissue changes in patients. Chronic neuroinflammation speculated to underlie secondary poststroke pathologies such as depression. Measured neuroinflammation in chronic stroke patients using [11C]PBR28 PET. First study showing extensive neuroinflammation in non-infarcted tissue in chronic stroke patients.
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Amor S, Nutma E, Marzin M, Puentes F. Imaging immunological processes from blood to brain in amyotrophic lateral sclerosis. Clin Exp Immunol 2021; 206:301-313. [PMID: 34510431 PMCID: PMC8561688 DOI: 10.1111/cei.13660] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 08/18/2021] [Accepted: 08/29/2021] [Indexed: 12/12/2022] Open
Abstract
Neuropathology studies of amyotrophic lateral sclerosis (ALS) and animal models of ALS reveal a strong association between aberrant protein accumulation and motor neurone damage, as well as activated microglia and astrocytes. While the role of neuroinflammation in the pathology of ALS is unclear, imaging studies of the central nervous system (CNS) support the idea that innate immune activation occurs early in disease in both humans and rodent models of ALS. In addition, emerging studies also reveal changes in monocytes, macrophages and lymphocytes in peripheral blood as well as at the neuromuscular junction. To more clearly understand the association of neuroinflammation (innate and adaptive) with disease progression, the use of biomarkers and imaging modalities allow monitoring of immune parameters in the disease process. Such approaches are important for patient stratification, selection and inclusion in clinical trials, as well as to provide readouts of response to therapy. Here, we discuss the different imaging modalities, e.g. magnetic resonance imaging, magnetic resonance spectroscopy and positron emission tomography as well as other approaches, including biomarkers of inflammation in ALS, that aid the understanding of the underlying immune mechanisms associated with motor neurone degeneration in ALS.
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Affiliation(s)
- Sandra Amor
- Department of Pathology, Amsterdam UMC Location VUmc, Amsterdam, the Netherlands.,Department of Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Erik Nutma
- Department of Pathology, Amsterdam UMC Location VUmc, Amsterdam, the Netherlands
| | - Manuel Marzin
- Department of Pathology, Amsterdam UMC Location VUmc, Amsterdam, the Netherlands
| | - Fabiola Puentes
- Department of Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
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Translation of 11C-labeled tracer synthesis to a CGMP environment as exemplified by [ 11C]ER176 for PET imaging of human TSPO. Nat Protoc 2021; 16:4419-4445. [PMID: 34363068 DOI: 10.1038/s41596-021-00584-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 06/07/2021] [Indexed: 11/08/2022]
Abstract
Radiotracers labeled with carbon-11 (t1/2 = 20.4 min) are widely used with positron emission tomography for biomedical research. Radiotracers must be produced for positron emission tomography studies in humans according to prescribed time schedules while also meeting current good manufacturing practice. Translation of an experimental radiosynthesis to a current good manufacturing practice environment is challenging. Here we exemplify such translation with a protocol for the production of an emerging radiotracer for imaging brain translocator protein 18 kDa, namely [11C]ER176. This radiotracer is produced by rapid conversion of cyclotron-produced [11C]carbon dioxide into [11C]iodomethane, which is then used to treat N-desmethyl-ER176 in the presence of base (tBuOK) at room temperature for 5 min. [11C]ER176 is separated in high purity by reversed-phase HPLC and formulated for intravenous injection in sterile ethanol-saline. The radiosynthesis is reliable and takes 50 min. Quality control takes another 20 min. All aspects of the protocol, including quality control, are discussed.
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38
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Ji B, Ono M, Yamasaki T, Fujinaga M, Zhang MR, Seki C, Aoki I, Kito S, Sawada M, Suhara T, Sahara N, Higuchi M. Detection of Alzheimer's disease-related neuroinflammation by a PET ligand selective for glial versus vascular translocator protein. J Cereb Blood Flow Metab 2021; 41:2076-2089. [PMID: 33557690 PMCID: PMC8327108 DOI: 10.1177/0271678x21992457] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A substantial and constitutive expression of translocator protein (TSPO) in cerebral blood vessels hampers the sensitive detection of neuroinflammation characterized by greatly induced TSPO expression in activated glia. Here, we conducted in vivo positron emission tomography (PET) and in vitro autoradiographic imaging of normal and TSPO-deficient mouse brains to compare the binding properties of 18F-FEBMP, a relatively novel TSPO radioligand developed for human studies based on its insensitivity to a common polymorphism, with 11C-PK11195, as well as other commonly used TSPO radioligands including 11C-PBR28, 11C-Ac5216 and 18F-FEDAA1106. TSPO in cerebral vessels of normal mice was found to provide a major binding site for 11C-PK11195, 11C-PBR28 and 18F-FEDAA1106, in contrast to no overt specific binding of 18F-FEBMP and 11C-Ac5216 to this vascular component. In addition, 18F-FEBMP yielded PET images of microglial TSPO with a higher contrast than 11C-PK11195 in a tau transgenic mouse modeling Alzheimer's disease (AD) and allied neurodegenerative tauopathies. Moreover, TSPO expression examined by immunoblotting was significantly increased in AD brains compared with healthy controls, and was well correlated with the autoradiographic binding of 18F-FEBMP but not 11C-PK11195. Our findings support the potential advantage of comparatively glial TSPO-selective radioligands such as 18F-FEBMP for PET imaging of inflammatory glial cells.
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Affiliation(s)
- Bin Ji
- Department of Functional Brain Imaging Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Maiko Ono
- Department of Functional Brain Imaging Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Tomoteru Yamasaki
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Masayuki Fujinaga
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Ming-Rong Zhang
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Chie Seki
- Department of Functional Brain Imaging Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Ichio Aoki
- Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Seiji Kito
- Research, Development and Support Center, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Makoto Sawada
- Department of Brain Function, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Aichi, Japan
| | - Tetsuya Suhara
- Department of Functional Brain Imaging Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Naruhiko Sahara
- Department of Functional Brain Imaging Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Makoto Higuchi
- Department of Functional Brain Imaging Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
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Mattner F, Katsifis A, Bourdier T, Loc'h C, Berghofer P, Fookes C, Hung TT, Jackson T, Henderson D, Pham T, Lee BJ, Shepherd R, Greguric I, Wyatt N, Le T, Poon J, Power C, Fulham M. Synthesis and pharmacological evaluation of [ 18F]PBR316: a novel PET ligand targeting the translocator protein 18 kDa (TSPO) with low binding sensitivity to human single nucleotide polymorphism rs6971. RSC Med Chem 2021; 12:1207-1221. [PMID: 34355185 PMCID: PMC8292990 DOI: 10.1039/d1md00035g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 03/15/2021] [Indexed: 02/04/2023] Open
Abstract
Radiopharmaceuticals that target the translocator protein 18 kDa (TSPO) have been investigated with positron emission tomography (PET) to study neuroinflammation, neurodegeneration and cancer. We have developed the novel, achiral, 2-phenylimidazo[1,2-a]pyridine, PBR316 that targets the translocator protein 18 kDa (TSPO) that addresses some of the limitations inherent in current TSPO ligands; namely specificity in binding, blood brain barrier permeability, metabolism and insensitivity to TSPO binding in subjects as a result of rs6971 polymorphism. PBR316 has high nanomolar affinity (4.7-6.0 nM) for the TSPO, >5000 nM for the central benzodiazepine receptor (CBR) and low sensitivity to rs6971 polymorphism with a low affinity binders (LABs) to high affinity binders (HABs) ratio of 1.5. [18F]PBR316 was prepared in 20 ± 5% radiochemical yield, >99% radiochemical purity and a molar activity of 160-400 GBq μmol-1. Biodistribution in rats showed high uptake of [18F]PBR316 in organs known to express TSPO such as heart (3.9%) and adrenal glands (7.5% ID per g) at 1 h. [18F]PBR316 entered the brain and accumulated in TSPO-expressing regions with an olfactory bulb to brain ratio of 3 at 15 min and 7 at 4 h. Radioactivity was blocked by PK11195 and Ro 5-4864 but not Flumazenil. Metabolite analysis showed that radioactivity in adrenal glands and the brain was predominantly due to the intact radiotracer. PET-CT studies in mouse-bearing prostate tumour xenografts indicated biodistribution similar to rats with radioactivity in the tumour increasing with time. [18F]PBR316 shows in vitro binding that is insensitive to human polymorphism and has specific and selective in vivo binding to the TSPO. [18F]PBR316 is suitable for further biological and clinical studies.
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Affiliation(s)
- Filomena Mattner
- Department of Molecular Imaging, Royal Prince Alfred Hospital Camperdown NSW 2050 Australia
| | - Andrew Katsifis
- Department of Molecular Imaging, Royal Prince Alfred Hospital Camperdown NSW 2050 Australia
- School of Pharmacy, University of Sydney Sydney NSW 2006 Australia
| | - Thomas Bourdier
- Department of Molecular Imaging, Royal Prince Alfred Hospital Camperdown NSW 2050 Australia
| | - Christian Loc'h
- Australian Nuclear Science and Technology Organisation Lucas Heights NSW Australia
| | - Paula Berghofer
- Australian Nuclear Science and Technology Organisation Lucas Heights NSW Australia
| | - Christopher Fookes
- Australian Nuclear Science and Technology Organisation Lucas Heights NSW Australia
| | - Tzong-Tyng Hung
- Biological Resources Imaging Laboratory, University of New South Wales Sydney NSW Australia
| | - Timothy Jackson
- Australian Nuclear Science and Technology Organisation Lucas Heights NSW Australia
| | - David Henderson
- Department of Molecular Imaging, Royal Prince Alfred Hospital Camperdown NSW 2050 Australia
| | - Tien Pham
- Australian Nuclear Science and Technology Organisation Lucas Heights NSW Australia
| | - Brendan J Lee
- Biological Resources Imaging Laboratory, University of New South Wales Sydney NSW Australia
| | - Rachael Shepherd
- Australian Nuclear Science and Technology Organisation Lucas Heights NSW Australia
| | - Ivan Greguric
- Australian Nuclear Science and Technology Organisation Lucas Heights NSW Australia
| | - Naomi Wyatt
- Australian Nuclear Science and Technology Organisation Lucas Heights NSW Australia
| | - Thanh Le
- Department of Molecular Imaging, Royal Prince Alfred Hospital Camperdown NSW 2050 Australia
| | - Jackson Poon
- Department of Molecular Imaging, Royal Prince Alfred Hospital Camperdown NSW 2050 Australia
| | - Carl Power
- Biological Resources Imaging Laboratory, University of New South Wales Sydney NSW Australia
| | - Michael Fulham
- Department of Molecular Imaging, Royal Prince Alfred Hospital Camperdown NSW 2050 Australia
- Faculty of Engineering and Information Technologies, University of Sydney Sydney NSW 2006 Australia
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Giordani A, Menziani MC, Moresco RM, Matarrese M, Paolino M, Saletti M, Giuliani G, Anzini M, Cappelli A. Exploring Translocator Protein (TSPO) Medicinal Chemistry: An Approach for Targeting Radionuclides and Boron Atoms to Mitochondria. J Med Chem 2021; 64:9649-9676. [PMID: 34254805 DOI: 10.1021/acs.jmedchem.1c00379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Translocator protein 18 kDa [TSPO or peripheral-type benzodiazepine receptor (PBR)] was identified in the search of binding sites for benzodiazepine anxiolytic drugs in peripheral regions. In these areas, binding sites for TSPO ligands were recognized in steroid-producing tissues. TSPO plays an important role in many cellular functions, and its coding sequence is highly conserved across species. TSPO is located predominantly on the membrane of mitochondria and is overexpressed in several solid cancers. TSPO basal expression in the CNS is low, but it becomes high in neurodegenerative conditions. Thus, TSPO constitutes not only as an outstanding drug target but also as a valuable marker for the diagnosis of a number of diseases. The aim of the present article is to show the lesson we have learned from our activity in TSPO medicinal chemistry and in approaching the targeted delivery to mitochondria by means of TSPO ligands.
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Affiliation(s)
- Antonio Giordani
- Rottapharm Biotech S.p.A., Via Valosa di Sopra 9, 20900 Monza, Italy
| | - Maria Cristina Menziani
- Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia, Via Campi 103, 41121 Modena, Italy
| | - Rosa Maria Moresco
- Department of Medicine and Surgery, University of Milan-Bicocca, Nuclear Medicine Department, San Raffaele Scientific Institute, IBFM-CNR, Via Olgettina 60, 20132 Milano, Italy
| | - Mario Matarrese
- Department of Medicine and Surgery, University of Milan-Bicocca, Nuclear Medicine Department, San Raffaele Scientific Institute, IBFM-CNR, Via Olgettina 60, 20132 Milano, Italy
| | - Marco Paolino
- Dipartimento di Biotecnologie, Chimica e Farmacia (Dipartimento di Eccellenza 2018-2022), Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Mario Saletti
- Dipartimento di Biotecnologie, Chimica e Farmacia (Dipartimento di Eccellenza 2018-2022), Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Germano Giuliani
- Dipartimento di Biotecnologie, Chimica e Farmacia (Dipartimento di Eccellenza 2018-2022), Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Maurizio Anzini
- Dipartimento di Biotecnologie, Chimica e Farmacia (Dipartimento di Eccellenza 2018-2022), Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Andrea Cappelli
- Dipartimento di Biotecnologie, Chimica e Farmacia (Dipartimento di Eccellenza 2018-2022), Università di Siena, Via A. Moro 2, 53100 Siena, Italy
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Auriemma R, Sponchioni M, Capasso Palmiero U, Rossino G, Rossetti A, Marsala A, Collina S, Sacchetti A, Moscatelli D, Peviani M. Synthesis and Characterization of a "Clickable" PBR28 TSPO-Selective Ligand Derivative Suitable for the Functionalization of Biodegradable Polymer Nanoparticles. NANOMATERIALS 2021; 11:nano11071693. [PMID: 34203263 PMCID: PMC8308144 DOI: 10.3390/nano11071693] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 05/21/2021] [Accepted: 06/22/2021] [Indexed: 02/04/2023]
Abstract
Reactive microgliosis is a pathological hallmark that accompanies neuronal demise in many neurodegenerative diseases, ranging from acute brain/spinal cord injuries to chronic diseases, such as amyotrophic lateral sclerosis (ALS), Alzheimer’s disease (AD) and age-related dementia. One strategy to assess and monitor microgliosis is to use positron emission tomography (PET) by exploiting radioligands selective for the 18 kDa translocator protein (TSPO) which is highly upregulated in the brain in pathological conditions. Several TSPO ligands have been developed and validated, so far. Among these, PBR28 has been widely adopted for PET imaging at both preclinical and clinical levels, thanks to its high brain penetration and high selectivity. For this reason, PBR28 represents a good candidate for functionalization strategies, where this ligand could be exploited to drive selective targeting of TSPO-expressing cells. Since the PBR28 structure lacks functional moieties that could be exploited for derivatization, in this work we explored a synthetic pathway for the synthesis of a PBR28 derivative carrying an alkyne group (PBR-alkyne), enabling the fast conjugation of the ligand through azide-alkyne cycloaddition, also known as click-chemistry. As a proof of concept, we demonstrated in silico that the derivatized PBR28 ligand maintains the capability to fit into the TSPO binding pocked, and we successfully exploited PBR-alkyne to decorate zwitterionic biodegradable polymer nanoparticles (NPs) resulting in efficient internalization in cultured microglia-like cell lines.
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Affiliation(s)
- Renato Auriemma
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy; (R.A.); (A.R.); (A.S.); (D.M.)
| | - Mattia Sponchioni
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy; (R.A.); (A.R.); (A.S.); (D.M.)
- Correspondence: (M.S.); (M.P.)
| | - Umberto Capasso Palmiero
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093 Zürich, Switzerland;
| | - Giacomo Rossino
- Department of Drug Sciences, University of Pavia, Via Taramelli 12, 27100 Pavia, Italy; (G.R.); (S.C.)
| | - Arianna Rossetti
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy; (R.A.); (A.R.); (A.S.); (D.M.)
| | - Andrea Marsala
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Via Ferrata 9, 27100 Pavia, Italy;
| | - Simona Collina
- Department of Drug Sciences, University of Pavia, Via Taramelli 12, 27100 Pavia, Italy; (G.R.); (S.C.)
| | - Alessandro Sacchetti
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy; (R.A.); (A.R.); (A.S.); (D.M.)
| | - Davide Moscatelli
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy; (R.A.); (A.R.); (A.S.); (D.M.)
| | - Marco Peviani
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Via Ferrata 9, 27100 Pavia, Italy;
- Gene Therapy Program, Dana Farber/Boston Children’s Cancer and Blood Disorders Center, 450 Brookline Ave., Boston, MA 02215, USA
- Harvard Medical School, Boston, MA 02115, USA
- Correspondence: (M.S.); (M.P.)
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Chen DL, Agapov E, Wu K, Engle JT, Solingapuram Sai KK, Arentson E, Spayd KJ, Moreland KT, Toth K, Byers DE, Pierce RA, Atkinson JJ, Laforest R, Gelman AE, Holtzman MJ. Selective Imaging of Lung Macrophages Using [ 11C]PBR28-Based Positron Emission Tomography. Mol Imaging Biol 2021; 23:905-913. [PMID: 34137002 DOI: 10.1007/s11307-021-01617-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 05/13/2021] [Accepted: 05/19/2021] [Indexed: 01/17/2023]
Abstract
PURPOSE We tested whether the translocator protein (TSPO)-targeted positron emission tomography (PET) tracer, N-acetyl-N-(2-[11C]methoxybenzyl)-2-phenoxy-5-pyridinamine ([11C]PBR28), could distinguish macrophage dominant from neutrophilic inflammation better than 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) in mouse models of lung inflammation and assessed TSPO association with macrophages in lung tissue from the mouse models and in patients with chronic obstructive pulmonary disease (COPD). PROCEDURES MicroPET imaging quantified [11C]PBR28 and [18F]FDG lung uptake in wild-type (Wt) C57BL/6J or heterozygous transgenic monocyte-deficient Wt/opT mice at 49 days after Sendai virus (SeV) infection, during macrophage-dominant inflammation, and in Wt mice at 3 days after SeV infection or 24 h after endotoxin instillation during neutrophilic inflammation. Immunohistochemical staining for TSPO in macrophages and neutrophils was performed using Mac3 and Ly6G for cell identification in mouse lung sections and CD68 and neutrophil elastase (NE) in human lung sections taken from explanted lungs from patients with COPD undergoing lung transplantation and donor lungs rejected for transplantation. Differences in tracer uptake among SeV-infected, endotoxin-treated, and uninfected/untreated control mice and in TSPO staining between neutrophils and macrophage populations in human lung sections were tested using analysis of variance. RESULTS In Wt mice, [11C]PBR28 uptake (% injected dose/ml lung tissue) increased significantly with macrophage-dominant inflammation at 49 days (D49) after SeV infection compared to controls (p = <0.001) but not at 3 days (D49) after SeV infection (p = 0.167). [11C]PBR28 uptake was unchanged at 24 h after endotoxin instillation (p = 0.958). [18F]FDG uptake increased to a similar degree in D3 and D49 SeV-infected and endotoxin-treated Wt mice compared to controls with no significant difference in the degree of increase among the tested conditions. [11C]PBR28 but not [18F]FDG lung uptake at D49 post-SeV infection was attenuated in Wt/opT mice compared to Wt mice. TSPO localized predominantly to macrophages in mouse lung tissue by immunostaining, and TSPO staining intensity was significantly higher in CD68+ cells compared to neutrophils in the human lung sections. CONCLUSIONS PET imaging with [11C]PBR28 can specifically detect macrophages versus neutrophils during lung inflammation and may be a useful biomarker of macrophage accumulation in lung disease.
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Affiliation(s)
- Delphine L Chen
- Division of Radiological Sciences and Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA. .,Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA. .,Department of Radiology, University of Washington, Seattle Cancer Care Alliance, 1144 Eastlake Ave E, # LG2-200, Seattle, WA, 98109, USA.
| | - Eugene Agapov
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Kangyun Wu
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Jacquelyn T Engle
- Division of Radiological Sciences and Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Elizabeth Arentson
- Division of Radiological Sciences and Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Katherine J Spayd
- Division of Radiological Sciences and Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Kirby T Moreland
- Division of Radiological Sciences and Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Kelsey Toth
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Derek E Byers
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Richard A Pierce
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Jeffrey J Atkinson
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Richard Laforest
- Division of Radiological Sciences and Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Andrew E Gelman
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Michael J Holtzman
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
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Dominguini D, Steckert AV, Abatti MR, Generoso JS, Barichello T, Dal-Pizzol F. The Protective Effect of PK-11195 on Cognitive Impairment in Rats Survived of Polymicrobial Sepsis. Mol Neurobiol 2021; 58:2724-2733. [PMID: 33495933 DOI: 10.1007/s12035-021-02294-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/13/2021] [Indexed: 10/22/2022]
Abstract
Sepsis is an organ dysfunction caused by a host's unregulated response to infection, causing long-term brain dysfunction with microglial activation, the release of inflammatory components, and mitochondrial changes. Neuroinflammation can increase the expression of the 18-kD translocator protein (TSPO) in the mitochondria, leading to the activation of the microglia and the release of inflammatory components. The antagonist PK-11195 can modulate TSPO and reduce microglial activation and cognitive damage presented in an animal model of sepsis. The aim of this was to evaluate the effects of PK-11195 on long-term brain inflammation and cognitive impairment in an animal model of sepsis. Wistar rats, 60 days old, were submitted to cecal ligation and puncture (CLP) surgery, divided into groups control/saline, control/PK-11195, sepsis/saline, and sepsis/PK-11195. Immediately after surgery, the antagonist PK-11195 was administered at a dose of 3 mg/kg. Ten days after CLP surgery, the animals were submitted to behavioral tests and determination of brain inflammatory parameters. The sepsis/saline group presented cognitive damage. However, there was damage prevention in animals that received PK-11195. Besides, the sepsis increased the levels of cytokines and M1 microglia markers and caused oxidative damage. However, PK-11195 had the potential to decrease inflammation. These events show that the modulation of neuroinflammation during sepsis by PK-11195, possibly related to changes in TSPO, improves mitochondrial function in the animals' brains. In conclusion, the antagonist PK-11195 attenuated brain inflammation and prevented cognitive impairment in animals subjected to sepsis.
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Affiliation(s)
- Diogo Dominguini
- Laboratory of Experimental Pathophysiology, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, 88806-000, Brazil.
| | - Amanda V Steckert
- Laboratory of Experimental Pathophysiology, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, 88806-000, Brazil
| | - Mariane R Abatti
- Laboratory of Experimental Pathophysiology, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, 88806-000, Brazil
| | - Jaqueline S Generoso
- Laboratory of Experimental Pathophysiology, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, 88806-000, Brazil
| | - Tatiana Barichello
- Laboratory of Experimental Pathophysiology, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, 88806-000, Brazil
- Translational Psychiatry Program, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Felipe Dal-Pizzol
- Laboratory of Experimental Pathophysiology, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, 88806-000, Brazil
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Vettermann FJ, Harris S, Schmitt J, Unterrainer M, Lindner S, Rauchmann BS, Palleis C, Weidinger E, Beyer L, Eckenweber F, Schuster S, Biechele G, Ferschmann C, Milenkovic VM, Wetzel CH, Rupprecht R, Janowitz D, Buerger K, Perneczky R, Höglinger GU, Levin J, Haass C, Tonn JC, Niyazi M, Bartenstein P, Albert NL, Brendel M. Impact of TSPO Receptor Polymorphism on [ 18F]GE-180 Binding in Healthy Brain and Pseudo-Reference Regions of Neurooncological and Neurodegenerative Disorders. Life (Basel) 2021; 11:484. [PMID: 34073557 PMCID: PMC8229996 DOI: 10.3390/life11060484] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/19/2021] [Accepted: 05/21/2021] [Indexed: 12/20/2022] Open
Abstract
TSPO-PET tracers are sensitive to a single-nucleotide polymorphism (rs6971-SNP), resulting in low-, medium- and high-affinity binders (LABs, MABs and HABS), but the clinical relevance of [18F]GE-180 is still unclear. We evaluated the impact of rs6971-SNP on in vivo [18F]GE-180 binding in a healthy brain and in pseudo-reference tissue in neuro-oncological and neurodegenerative diseases. Standardized uptake values (SUVs) of [18F]GE-180-PET were assessed using a manually drawn region of interest in the frontoparietal and cerebellar hemispheres. The SUVs were compared between the LABs, MABs and HABs in control, glioma, four-repeat tauopathy (4RT) and Alzheimer's disease (AD) subjects. Second, the SUVs were compared between the patients and controls within their rs6971-subgroups. After excluding patients with prior therapy, 24 LABs (7 control, 5 glioma, 6 4RT and 6 AD) were analyzed. Age- and sex-matched MABs (n = 38) and HABs (n = 50) were selected. The LABs had lower frontoparietal and cerebellar SUVs when compared with the MABs and HABs, but no significant difference was observed between the MABs and HABs. Within each rs6971 group, no SUV difference between the patients and controls was detected in the pseudo-reference tissues. The rs6971-SNP affects [18F]GE-180 quantification, revealing lower binding in the LABs when compared to the MABs and HABs. The frontoparietal and cerebellar ROIs were successfully validated as pseudo-reference regions.
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Affiliation(s)
- Franziska J Vettermann
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Stefanie Harris
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Julia Schmitt
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Marcus Unterrainer
- Department of Radiology, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Simon Lindner
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Boris-Stephan Rauchmann
- Department of Radiology, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
- Department of Psychiatry and Psychotherapy, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Carla Palleis
- Department of Neurology, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Endy Weidinger
- Department of Neurology, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Leonie Beyer
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Florian Eckenweber
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Sebastian Schuster
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Gloria Biechele
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Christian Ferschmann
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Vladimir M Milenkovic
- Department of Psychiatry and Psychotherapy, University of Regensburg, 93053 Regensburg, Germany
| | - Christian H Wetzel
- Department of Psychiatry and Psychotherapy, University of Regensburg, 93053 Regensburg, Germany
| | - Rainer Rupprecht
- Department of Psychiatry and Psychotherapy, University of Regensburg, 93053 Regensburg, Germany
| | - Daniel Janowitz
- Institute for Stroke and Dementia Research, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Katharina Buerger
- Institute for Stroke and Dementia Research, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
| | - Robert Perneczky
- Department of Psychiatry and Psychotherapy, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Ageing Epidemiology (AGE) Research Unit, School of Public Health, Imperial College, London SW7 2AZ, UK
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Günter U Höglinger
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Johannes Levin
- Department of Neurology, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Christian Haass
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
- Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, LMU Munich, 82152 Planegg, Germany
| | - Joerg C Tonn
- Department of Neurosurgery, University Hospital of Munich, 81377 Munich, Germany
| | - Maximilian Niyazi
- Department of Radiation Oncology, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
- German Cancer Consortium (DKTK), Partner Site Munich, 81377 Munich, Germany
| | - Peter Bartenstein
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Nathalie L Albert
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
- German Cancer Consortium (DKTK), Partner Site Munich, 81377 Munich, Germany
| | - Matthias Brendel
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, 81377 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
- German Cancer Consortium (DKTK), Partner Site Munich, 81377 Munich, Germany
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Zürcher NR, Loggia ML, Mullett JE, Tseng C, Bhanot A, Richey L, Hightower BG, Wu C, Parmar AJ, Butterfield RI, Dubois JM, Chonde DB, Izquierdo-Garcia D, Wey HY, Catana C, Hadjikhani N, McDougle CJ, Hooker JM. [ 11C]PBR28 MR-PET imaging reveals lower regional brain expression of translocator protein (TSPO) in young adult males with autism spectrum disorder. Mol Psychiatry 2021; 26:1659-1669. [PMID: 32076115 PMCID: PMC8159742 DOI: 10.1038/s41380-020-0682-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 01/12/2020] [Accepted: 02/06/2020] [Indexed: 12/19/2022]
Abstract
Mechanisms of neuroimmune and mitochondrial dysfunction have been repeatedly implicated in autism spectrum disorder (ASD). To examine these mechanisms in ASD individuals, we measured the in vivo expression of the 18 kDa translocator protein (TSPO), an activated glial marker expressed on mitochondrial membranes. Participants underwent scanning on a simultaneous magnetic resonance-positron emission tomography (MR-PET) scanner with the second-generation TSPO radiotracer [11C]PBR28. By comparing TSPO in 15 young adult males with ASD with 18 age- and sex-matched controls, we showed that individuals with ASD exhibited lower regional TSPO expression in several brain regions, including the bilateral insular cortex, bilateral precuneus/posterior cingulate cortex, and bilateral temporal, angular, and supramarginal gyri, which have previously been implicated in autism in functional MR imaging studies. No brain region exhibited higher regional TSPO expression in the ASD group compared with the control group. A subset of participants underwent a second MR-PET scan after a median interscan interval of 3.6 months, and we determined that TSPO expression over this period of time was stable and replicable. Furthermore, voxelwise analysis confirmed lower regional TSPO expression in ASD at this later time point. Lower TSPO expression in ASD could reflect abnormalities in neuroimmune processes or mitochondrial dysfunction.
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Affiliation(s)
- N R Zürcher
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA.
- Harvard Medical School, Boston, MA, USA.
| | - M L Loggia
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - J E Mullett
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - C Tseng
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - A Bhanot
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - L Richey
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - B G Hightower
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - C Wu
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - A J Parmar
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - R I Butterfield
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - J M Dubois
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - D B Chonde
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - D Izquierdo-Garcia
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - H Y Wey
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - C Catana
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - N Hadjikhani
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Gillberg Neuropsychiatry Center, University of Gothenburg, Sahlgrenska Academy, Gothenburg, Sweden
| | - C J McDougle
- Harvard Medical School, Boston, MA, USA
- Lurie Center for Autism, Massachusetts General Hospital, Lexington, MA, USA
| | - J M Hooker
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA.
- Harvard Medical School, Boston, MA, USA.
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Akerele MI, Zein SA, Pandya S, Nikolopoulou A, Gauthier SA, Raj A, Henchcliffe C, Mozley PD, Karakatsanis NA, Gupta A, Babich J, Nehmeh SA. Population-based input function for TSPO quantification and kinetic modeling with [ 11C]-DPA-713. EJNMMI Phys 2021; 8:39. [PMID: 33914185 PMCID: PMC8085191 DOI: 10.1186/s40658-021-00381-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 03/29/2021] [Indexed: 11/23/2022] Open
Abstract
INTRODUCTION Quantitative positron emission tomography (PET) studies of neurodegenerative diseases typically require the measurement of arterial input functions (AIF), an invasive and risky procedure. This study aims to assess the reproducibility of [11C]DPA-713 PET kinetic analysis using population-based input function (PBIF). The final goal is to possibly eliminate the need for AIF. MATERIALS AND METHODS Eighteen subjects including six healthy volunteers (HV) and twelve Parkinson disease (PD) subjects from two [11C]-DPA-713 PET studies were included. Each subject underwent 90 min of dynamic PET imaging. Five healthy volunteers underwent a test-retest scan within the same day to assess the repeatability of the kinetic parameters. Kinetic modeling was carried out using the Logan total volume of distribution (VT) model. For each data set, kinetic analysis was performed using a patient-specific AIF (PSAIF, ground-truth standard) and then repeated using the PBIF. PBIF was generated using the leave-one-out method for each subject from the remaining 17 subjects and after normalizing the PSAIFs by 3 techniques: (a) Weightsubject×DoseInjected, (b) area under AIF curve (AUC), and (c) Weightsubject×AUC. The variability in the VT measured with PSAIF, in the test-retest study, was determined for selected brain regions (white matter, cerebellum, thalamus, caudate, putamen, pallidum, brainstem, hippocampus, and amygdala) using the Bland-Altman analysis and for each of the 3 normalization techniques. Similarly, for all subjects, the variabilities due to the use of PBIF were assessed. RESULTS Bland-Altman analysis showed systematic bias between test and retest studies. The corresponding mean bias and 95% limits of agreement (LOA) for the studied brain regions were 30% and ± 70%. Comparing PBIF- and PSAIF-based VT estimate for all subjects and all brain regions, a significant difference between the results generated by the three normalization techniques existed for all brain structures except for the brainstem (P-value = 0.095). The mean % difference and 95% LOA is -10% and ±45% for Weightsubject×DoseInjected; +8% and ±50% for AUC; and +2% and ± 38% for Weightsubject×AUC. In all cases, normalizing by Weightsubject×AUC yielded the smallest % bias and variability (% bias = ±2%; LOA = ±38% for all brain regions). Estimating the reproducibility of PBIF-kinetics to PSAIF based on disease groups (HV/PD) and genotype (MAB/HAB), the average VT values for all regions obtained from PBIF is insignificantly higher than PSAIF (%difference = 4.53%, P-value = 0.73 for HAB; and %difference = 0.73%, P-value = 0.96 for MAB). PBIF also tends to overestimate the difference between PD and HV for HAB (% difference = 32.33% versus 13.28%) and underestimate it in MAB (%difference = 6.84% versus 20.92%). CONCLUSIONS PSAIF kinetic results are reproducible with PBIF, with variability in VT within that obtained for the test-retest studies. Therefore, VT assessed using PBIF-based kinetic modeling is clinically feasible and can be an alternative to PSAIF.
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Affiliation(s)
- Mercy I Akerele
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA.
| | - Sara A Zein
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA
| | - Sneha Pandya
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA
| | | | - Susan A Gauthier
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA
- Department of Neurology, Weill Cornell Medical College, New York, NY, 10021, USA
- Feil Family Brain and Mind Institute, Weill Cornell Medical College, New York, NY, 10021, USA
| | - Ashish Raj
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA
| | - Claire Henchcliffe
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA
- Department of Neurology, Weill Cornell Medical College, New York, NY, 10021, USA
| | - P David Mozley
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA
| | | | - Ajay Gupta
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA
| | - John Babich
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA
| | - Sadek A Nehmeh
- Department of Radiology, Weill Cornell Medical College, New York, NY, 10021, USA
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Positron Emission Tomography Imaging of Macrophages in Cancer. Cancers (Basel) 2021; 13:cancers13081921. [PMID: 33923410 PMCID: PMC8072570 DOI: 10.3390/cancers13081921] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/13/2021] [Accepted: 04/13/2021] [Indexed: 12/14/2022] Open
Abstract
Macrophages are large phagocytic cells that can be classified as a type of white blood cell and may be either mobile or stationary in tissues. The presence of macrophages in essentially every major disease makes them attractive candidates to serve as therapeutic targets and diagnostic biomarkers. Macrophages that are found in the microenvironment of solid tumors are referred to as tumor-associated macrophages (TAMs) and have been shown to influence chemoresistance, immune regulation, tumor initiation and tumor growth. The imaging of TAMs through Positron Emission Tomography (PET) has the potential to provide valuable information on cancer biology, tumor progression, and response to therapy. This review will highlight the versatility of macrophage imaging in cancer through the use of PET.
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Pascual B, Funk Q, Zanotti-Fregonara P, Cykowski MD, Veronese M, Rockers E, Bradbury K, Yu M, Nakawah MO, Román GC, Schulz PE, Arumanayagam AS, Beers D, Faridar A, Fujita M, Appel SH, Masdeu JC. Neuroinflammation is highest in areas of disease progression in semantic dementia. Brain 2021; 144:1565-1575. [PMID: 33824991 DOI: 10.1093/brain/awab057] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 11/25/2020] [Accepted: 12/10/2020] [Indexed: 12/11/2022] Open
Abstract
Despite epidemiological and genetic data linking semantic dementia to inflammation, the topography of neuroinflammation in semantic dementia, also known as the semantic variant of primary progressive aphasia, remains unclear. The pathology starts at the tip of the left temporal lobe where, in addition to cortical atrophy, a strong signal appears with the tau PET tracer 18F-flortaucipir, even though the disease is not typically associated with tau but with TDP-43 protein aggregates. Here, we characterized the topography of inflammation in semantic variant primary progressive aphasia using high-resolution PET and the tracer 11C-PBR28 as a marker of microglial activation. We also tested the hypothesis that inflammation, by providing non-specific binding targets, could explain the 18F-flortaucipir signal in semantic variant primary progressive aphasia. Eight amyloid-PET-negative patients with semantic variant primary progressive aphasia underwent 11C-PBR28 and 18F-flortaucipir PET. Healthy controls underwent 11C-PBR28 PET (n = 12) or 18F-flortaucipir PET (n = 12). Inflammation in PET with 11C-PBR28 was analysed using Logan graphical analysis with a metabolite-corrected arterial input function. 18F-flortaucipir standardized uptake value ratios were calculated using the cerebellum as the reference region. Since monoamine oxidase B receptors are expressed by astrocytes in affected tissue, selegiline was administered to one patient with semantic variant primary progressive aphasia before repeating 18F-flortaucipir scanning to test whether monoamine oxidase B inhibition blocked flortaucipir binding, which it did not. While 11C-PBR28 uptake was mostly cortical, 18F-flortaucipir uptake was greatest in the white matter. The uptake of both tracers was increased in the left temporal lobe and in the right temporal pole, as well as in regions adjoining the left temporal pole such as insula and orbitofrontal cortex. However, peak uptake of 18F-flortaucipir localized to the left temporal pole, the epicentre of pathology, while the peak of inflammation 11C-PBR28 uptake localized to a more posterior, mid-temporal region and left insula and orbitofrontal cortex, in the periphery of the damage core. Neuroinflammation, greatest in the areas of progression of the pathological process in semantic variant primary progressive aphasia, should be further studied as a possible therapeutic target to slow disease progression.
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Affiliation(s)
- Belen Pascual
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Quentin Funk
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Paolo Zanotti-Fregonara
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Matthew D Cykowski
- Department of Pathology and Genomic Medicine, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA.,Stanley H. Appel Department of Neurology, Houston Methodist Neurological Institute, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Mattia Veronese
- Centre for Neuroimaging Sciences, King's College London, London, UK
| | - Elijah Rockers
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Kathleen Bradbury
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Meixiang Yu
- Cyclotron and Radiopharmaceutical Core, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Mohammad O Nakawah
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Gustavo C Román
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Paul E Schulz
- Department of Neurology, McGovern Medical School of UT Health, Houston, TX, USA
| | - Anithachristy S Arumanayagam
- Department of Pathology and Genomic Medicine, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - David Beers
- Stanley H. Appel Department of Neurology, Houston Methodist Neurological Institute, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Alireza Faridar
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Masahiro Fujita
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Stanley H Appel
- Stanley H. Appel Department of Neurology, Houston Methodist Neurological Institute, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
| | - Joseph C Masdeu
- Nantz National Alzheimer Center, Stanley H. Appel Department of Neurology, Houston Methodist Research Institute, Weill Cornell Medicine, Houston, TX, USA
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MacAskill MG, Stadulyte A, Williams L, Morgan TEF, Sloan NL, Alcaide-Corral CJ, Walton T, Wimberley C, McKenzie CA, Spath N, Mungall W, BouHaidar R, Dweck MR, Gray GA, Newby DE, Lucatelli C, Sutherland A, Pimlott SL, Tavares AAS. Quantification of Macrophage-Driven Inflammation During Myocardial Infarction with 18F-LW223, a Novel TSPO Radiotracer with Binding Independent of the rs6971 Human Polymorphism. J Nucl Med 2021; 62:536-544. [PMID: 32859708 PMCID: PMC8049364 DOI: 10.2967/jnumed.120.243600] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 07/28/2020] [Indexed: 01/09/2023] Open
Abstract
Myocardial infarction (MI) is one of the leading causes of death worldwide, and inflammation is central to tissue response and patient outcomes. The 18-kDa translocator protein (TSPO) has been used in PET as an inflammatory biomarker. The aims of this study were to screen novel, fluorinated, TSPO radiotracers for susceptibility to the rs6971 genetic polymorphism using in vitro competition binding assays in human brain and heart; assess whether the in vivo characteristics of our lead radiotracer, 18F-LW223, are suitable for clinical translation; and validate whether 18F-LW223 can detect macrophage-driven inflammation in a rat MI model. Methods: Fifty-one human brain and 29 human heart tissue samples were screened for the rs6971 polymorphism. Competition binding assays were conducted with 3H-PK11195 and the following ligands: PK11195, PBR28, and our novel compounds (AB5186 and LW223). Naïve rats and mice were used for in vivo PET kinetic studies, radiometabolite studies, and dosimetry experiments. Rats underwent permanent coronary artery ligation and were scanned using PET/CT with an invasive input function at 7 d after MI. For quantification of PET signal in the hypoperfused myocardium, K1 (rate constant for transfer from arterial plasma to tissues) was used as a surrogate marker of perfusion to correct the binding potential for impaired radiotracer transfer from plasma to tissue (BPTC). Results: LW223 binding to TSPO was not susceptible to the rs6971 genetic polymorphism in human brain and heart samples. In rodents, 18F-LW223 displayed a specific uptake consistent with TSPO expression, a slow metabolism in blood (69% of parent at 120 min), a high plasma free fraction of 38.5%, and a suitable dosimetry profile (effective dose of 20.5-24.5 μSv/MBq). 18F-LW223 BPTC was significantly higher in the MI cohort within the infarct territory of the anterior wall relative to the anterior wall of naïve animals (32.7 ± 5.0 vs. 10.0 ± 2.4 cm3/mL/min, P ≤ 0.001). Ex vivo immunofluorescent staining for TSPO and CD68 (macrophage marker) resulted in the same pattern seen with in vivo BPTC analysis. Conclusion:18F-LW223 is not susceptible to the rs6971 genetic polymorphism in in vitro assays, has favorable in vivo characteristics, and is able to accurately map macrophage-driven inflammation after MI.
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Affiliation(s)
- Mark G MacAskill
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
| | - Agne Stadulyte
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
| | - Lewis Williams
- School of Chemistry, WestCHEM, University of Glasgow, Glasgow, United Kingdom
| | - Timaeus E F Morgan
- School of Chemistry, WestCHEM, University of Glasgow, Glasgow, United Kingdom
| | - Nikki L Sloan
- School of Chemistry, WestCHEM, University of Glasgow, Glasgow, United Kingdom
| | - Carlos J Alcaide-Corral
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
| | - Tashfeen Walton
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
| | - Catriona Wimberley
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Chris-Anne McKenzie
- MRC Edinburgh Brain Tissue Bank, University of Edinburgh, Edinburgh, United Kingdom
| | - Nick Spath
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - William Mungall
- Bioresearch and Veterinary Services, University of Edinburgh, Edinburgh, United Kingdom
| | - Ralph BouHaidar
- Forensic Pathology, University of Edinburgh, Edinburgh, United Kingdom
| | - Marc R Dweck
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Gillian A Gray
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - David E Newby
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Andrew Sutherland
- School of Chemistry, WestCHEM, University of Glasgow, Glasgow, United Kingdom
| | - Sally L Pimlott
- School of Medicine, University of Glasgow, Glasgow, United Kingdom; and
- NHS Greater Glasgow and Clyde, Glasgow, United Kingdom
| | - Adriana A S Tavares
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, University of Edinburgh, Edinburgh, United Kingdom
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50
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Li X, Zhang K, He X, Zhou J, Jin C, Shen L, Gao Y, Tian M, Zhang H. Structural, Functional, and Molecular Imaging of Autism Spectrum Disorder. Neurosci Bull 2021; 37:1051-1071. [PMID: 33779890 DOI: 10.1007/s12264-021-00673-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/20/2020] [Indexed: 12/21/2022] Open
Abstract
Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder associated with both genetic and environmental risks. Neuroimaging approaches have been widely employed to parse the neurophysiological mechanisms underlying ASD, and provide critical insights into the anatomical, functional, and neurochemical changes. We reviewed recent advances in neuroimaging studies that focused on ASD by using magnetic resonance imaging (MRI), positron emission tomography (PET), or single-positron emission tomography (SPECT). Longitudinal structural MRI has delineated an abnormal developmental trajectory of ASD that is associated with cascading neurobiological processes, and functional MRI has pointed to disrupted functional neural networks. Meanwhile, PET and SPECT imaging have revealed that metabolic and neurotransmitter abnormalities may contribute to shaping the aberrant neural circuits of ASD. Future large-scale, multi-center, multimodal investigations are essential to elucidate the neurophysiological underpinnings of ASD, and facilitate the development of novel diagnostic biomarkers and better-targeted therapy.
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Affiliation(s)
- Xiaoyi Li
- Department of Nuclear Medicine and Medical PET Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China
- Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, 310009, China
- Institute of Nuclear Medicine and Molecular Imaging, Zhejiang University, Hangzhou, 310009, China
| | - Kai Zhang
- Laboratory for Pathophysiological and Health Science, RIKEN Center for Biosystems Dynamics Research, Hyogo, 650-0047, Japan
| | - Xiao He
- Department of Nuclear Medicine and Medical PET Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China
- Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, 310009, China
- Institute of Nuclear Medicine and Molecular Imaging, Zhejiang University, Hangzhou, 310009, China
| | - Jinyun Zhou
- Department of Nuclear Medicine and Medical PET Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China
- Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, 310009, China
- Institute of Nuclear Medicine and Molecular Imaging, Zhejiang University, Hangzhou, 310009, China
| | - Chentao Jin
- Department of Nuclear Medicine and Medical PET Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China
- Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, 310009, China
- Institute of Nuclear Medicine and Molecular Imaging, Zhejiang University, Hangzhou, 310009, China
| | - Lesang Shen
- Department of Surgical Oncology, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China
| | - Yuanxue Gao
- Department of Nuclear Medicine and Medical PET Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China
- Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, 310009, China
- Institute of Nuclear Medicine and Molecular Imaging, Zhejiang University, Hangzhou, 310009, China
| | - Mei Tian
- Department of Nuclear Medicine and Medical PET Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China.
- Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, 310009, China.
- Institute of Nuclear Medicine and Molecular Imaging, Zhejiang University, Hangzhou, 310009, China.
| | - Hong Zhang
- Department of Nuclear Medicine and Medical PET Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China.
- Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, 310009, China.
- Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang University, Hangzhou, 310027, China.
- Institute of Nuclear Medicine and Molecular Imaging, Zhejiang University, Hangzhou, 310009, China.
- The College of Biomedical Engineering and Instrument Science of Zhejiang University, Hangzhou, 310027, China.
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