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Li KP, Cai H. An Improved HPLC Separation Method for TSPO Radioligand [ 11C]ER176 Clinical Production. J Labelled Comp Radiopharm 2024; 67:273-276. [PMID: 38641899 DOI: 10.1002/jlcr.4093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 03/13/2024] [Accepted: 03/21/2024] [Indexed: 04/21/2024]
Abstract
Mitochondrial membrane translocator protein 18 kDa (TSPO) expression is increased in activated microglia, established as a plausible target of neuroinflammation imaging. [11C]ER176, specifically binding to TSPO, has been developed as the third generation of radioligand for PET imaging of TSPO, which showed the potential in better quantifying neuroinflammation than its predecessors. In the current study, we developed an automated radiosynthesis with an improved HPLC purification method for [11C]ER176 clinical production. The improved HPLC separation was integrated into the automated production of [11C]ER176 using a reverse phase semi-preparative HPLC column with an isocratic pump and the mixture of methanol and 50 mM ammonium acetate as the mobile phase. The fraction corresponding to [11C]ER176 was collected around 8.5-9.0 min without the risk of getting contaminations from nearby impurities. The automated production process took about 30 min after end of bombardment (EOB) and the quality of the final product [11C]ER176 met all specifications for clinical use based on current US Pharmacopeia and FDA CGMP requirements.
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Affiliation(s)
- Kang-Po Li
- Department of Radiology, Mayo Clinic, Jacksonville, Florida, USA
| | - Hancheng Cai
- Department of Radiology, Mayo Clinic, Jacksonville, Florida, USA
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Booth S, Ko JH. Radionuclide Imaging of the Neuroanatomical and Neurochemical Substrate of Cognitive Decline in Parkinson's Disease. Nucl Med Mol Imaging 2024; 58:213-226. [PMID: 38932760 PMCID: PMC11196570 DOI: 10.1007/s13139-024-00842-9] [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: 09/30/2023] [Revised: 01/10/2024] [Accepted: 01/17/2024] [Indexed: 06/28/2024] Open
Abstract
Cognitive impairment is a frequent manifestation of Parkinson's disease (PD), resulting in decrease in patients' quality of life and increased societal and economic burden. However, cognitive decline in PD is highly heterogenous and the mechanisms are poorly understood. Radionuclide imaging techniques like positron emission tomography (PET) and single photon emission computed tomography (SPECT) have been used to investigate the neurochemical and neuroanatomical substrate of cognitive decline in PD. These techniques allow the assessment of different neurotransmitter systems, changes in brain glucose metabolism, proteinopathy, and neuroinflammation in vivo in PD patients. Here, we review current radionuclide imaging research on cognitive deficit in PD with a focus on predicting accelerating cognitive decline. This research could assist in the development of prognostic biomarkers for patient stratification and have utility in the development of ameliorative or disease-modifying therapies targeting cognitive deficit in PD.
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Affiliation(s)
- Samuel Booth
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, 130-745 Bannatyne Ave, Winnipeg, MB R3E 0J9 Canada
- PrairieNeuro Research Centre, Kleysen Institute of Advanced Medicine, Health Science Centre, Winnipeg, Canada
| | - Ji Hyun Ko
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, 130-745 Bannatyne Ave, Winnipeg, MB R3E 0J9 Canada
- PrairieNeuro Research Centre, Kleysen Institute of Advanced Medicine, Health Science Centre, Winnipeg, Canada
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Aceves-Serrano L, Neva JL, Munro J, Vavasour IM, Parent M, Boyd LA, Doudet DJ. Evaluation of microglia activation related markers following a clinical course of TBS: A non-human primate study. PLoS One 2024; 19:e0301118. [PMID: 38753646 PMCID: PMC11098425 DOI: 10.1371/journal.pone.0301118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 03/11/2024] [Indexed: 05/18/2024] Open
Abstract
While the applicability and popularity of theta burst stimulation (TBS) paradigms remain, current knowledge of their neurobiological effects is still limited, especially with respect to their impact on glial cells and neuroinflammatory processes. We used a multimodal imaging approach to assess the effects of a clinical course of TBS on markers for microglia activation and tissue injury as an indirect assessment of neuroinflammatory processes. Healthy non-human primates received continuous TBS (cTBS), intermittent TBS (iTBS), or sham stimulation over the motor cortex at 90% of resting motor threshold. Stimulation was delivered to the awake subjects 5 times a week for 3-4 weeks. Translocator protein (TSPO) expression was evaluated using Positron Emission Tomography and [11C]PBR28, and myo-inositol (mI) and N-acetyl-aspartate (NAA) concentrations were assessed with Magnetic Resonance Spectroscopy. Animals were then euthanized, and immunofluorescence staining was performed using antibodies against TSPO. Paired t-tests showed no significant changes in [11C]PBR28 measurements after stimulation. Similarly, no significant changes in mI and NAA concentrations were found. Post-mortem TSPO evaluation showed comparable mean immunofluorescence intensity after active TBS and sham delivery. The current study suggests that in healthy brains a clinical course of TBS, as evaluated with in-vivo imaging techniques (PET and MRS), did not measurably modulate the expression of glia related markers and metabolite associated with neural viability.
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Affiliation(s)
- Lucero Aceves-Serrano
- Department of Medicine, Division of Neurology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jason L. Neva
- Faculté de Médecine, École de Kinésiologie et des Sciences de l’activité Physique, Université de Montréal, Montreal, Quebec, Canada
- Centre de Recherche de l’institut Universitaire de Gériatrie de Montréal, Montreal, QC, Canada
| | - Jonathan Munro
- CERVO Brain Research Centre, Laval University, Quebec City, Quebec, Canada
| | - Irene M. Vavasour
- Faculty of Medicine, UBC MRI Research Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - Martin Parent
- CERVO Brain Research Centre, Laval University, Quebec City, Quebec, Canada
| | - Lara A. Boyd
- Faculty of Medicine, Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
- Faculty of Medicine, Graduate Program of Rehabilitation Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Doris J. Doudet
- Department of Medicine, Division of Neurology, University of British Columbia, Vancouver, British Columbia, Canada
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Pan J, Hu J, Meng D, Chen L, Wei X. Neuroinflammation in dementia: A meta-analysis of PET imaging studies. Medicine (Baltimore) 2024; 103:e38086. [PMID: 38701247 PMCID: PMC11062685 DOI: 10.1097/md.0000000000038086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 04/11/2024] [Indexed: 05/05/2024] Open
Abstract
BACKGROUND Dementia is a major public health challenge for aging societies worldwide. Neuroinflammation is thought to be a key factor in dementia development. The aim of this study was to comprehensively assess translocator protein (TSPO) expression by positron emission tomography (PET) imaging to reveal the characteristics of neuroinflammation in dementia. METHODS We used a meta-analysis to retrieve literature on TSPO expression in dementia using PET imaging technology, including but not limited to the quality of the study design, sample size, and the type of TSPO ligand used in the study. For the included studies, we extracted key data, including TSPO expression levels, clinical characteristics of the study participants, and specific information on brain regions. Meta-analysis was performed using R software to assess the relationship between TSPO expression and dementia. RESULTS After screening, 12 studies that met the criteria were included. The results of the meta-analysis showed that the expression level of TSPO was significantly elevated in patients with dementia, especially in the hippocampal region. The OR in the hippocampus was 1.50 with a 95% CI of 1.09 to 1.25, indicating a significant increase in the expression of TSPO in this region compared to controls. Elevated levels of inflammation in the prefrontal lobe and cingulate gyrus are associated with cognitive impairment in patients. This was despite an OR of 1.00 in the anterior cingulate gyrus, indicating that TSPO expression in this region did not correlate significantly with the findings. The overall heterogeneity test showed I² = 51%, indicating moderate heterogeneity. CONCLUSION This study summarizes the existing literature on TSPO expression in specific regions of the brain in patients with dementia, and also provides some preliminary evidence on the possible association between neuroinflammation and dementia. However, the heterogeneity of results and limitations of the study suggest that we need to interpret these findings with caution. Future studies need to adopt a more rigorous and consistent methodological design to more accurately assess the role of neuroinflammation in dementia, thereby providing a more reliable evidence base for understanding pathological mechanisms and developing potential therapeutic strategies.
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Affiliation(s)
- Jie Pan
- Department of Neurology, The First Hospital of Jiaxing (Affiliated Hospital of Jiaxing University), Jiaxing City, Zhejiang Province, China
| | - Jin Hu
- Department of Neurology, The First Hospital of Jiaxing (Affiliated Hospital of Jiaxing University), Jiaxing City, Zhejiang Province, China
| | - Danyang Meng
- Department of Neurology, The First Hospital of Jiaxing (Affiliated Hospital of Jiaxing University), Jiaxing City, Zhejiang Province, China
| | - Liang Chen
- Department of Head and Neck Surgery, The First Hospital of Jiaxing (Affiliated Hospital of Jiaxing University), Jiaxing City, Zhejiang Province, China
| | - Xianling Wei
- Department of Nuclear Medicine, The First Hospital of Jiaxing (Affiliated Hospital of Jiaxing University), Jiaxing City, Zhejiang Province, China
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5
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Sandström A, Torrado-Carvajal A, Morrissey EJ, Kim M, Alshelh Z, Zhu Y, Li MD, Chang CY, Jarraya M, Akeju O, Schrepf A, Harris RE, Kwon YM, Bedair H, Chen AF, Mercaldo ND, Kettner N, Napadow V, Toschi N, Edwards RR, Loggia ML. [ 11 C]-PBR28 positron emission tomography signal as an imaging marker of joint inflammation in knee osteoarthritis. Pain 2024; 165:1121-1130. [PMID: 38015622 DOI: 10.1097/j.pain.0000000000003114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 10/24/2023] [Indexed: 11/30/2023]
Abstract
ABSTRACT Although inflammation is known to play a role in knee osteoarthritis (KOA), inflammation-specific imaging is not routinely performed. In this article, we evaluate the role of joint inflammation, measured using [ 11 C]-PBR28, a radioligand for the inflammatory marker 18-kDa translocator protein (TSPO), in KOA. Twenty-one KOA patients and 11 healthy controls (HC) underwent positron emission tomography/magnetic resonance imaging (PET/MRI) knee imaging with the TSPO ligand [ 11 C]-PBR28. Standardized uptake values were extracted from regions-of-interest (ROIs) semiautomatically segmented from MRI data, and compared across groups (HC, KOA) and subgroups (unilateral/bilateral KOA symptoms), across knees (most vs least painful), and against clinical variables (eg, pain and Kellgren-Lawrence [KL] grades). Overall, KOA patients demonstrated elevated [ 11 C]-PBR28 binding across all knee ROIs, compared with HC (all P 's < 0.005). Specifically, PET signal was significantly elevated in both knees in patients with bilateral KOA symptoms (both P 's < 0.01), and in the symptomatic knee ( P < 0.05), but not the asymptomatic knee ( P = 0.95) of patients with unilateral KOA symptoms. Positron emission tomography signal was higher in the most vs least painful knee ( P < 0.001), and the difference in pain ratings across knees was proportional to the difference in PET signal ( r = 0.74, P < 0.001). Kellgren-Lawrence grades neither correlated with PET signal (left knee r = 0.32, P = 0.19; right knee r = 0.18, P = 0.45) nor pain ( r = 0.39, P = 0.07). The current results support further exploration of [ 11 C]-PBR28 PET signal as an imaging marker candidate for KOA and a link between joint inflammation and osteoarthritis-related pain severity.
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Affiliation(s)
- Angelica Sandström
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Angel Torrado-Carvajal
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
- Medical Image Analysis and Biometry Laboratory, Universidad Rey Juan Carlos, Madrid, Spain
| | - Erin J Morrissey
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Minhae Kim
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Zeynab Alshelh
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Yehui Zhu
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Matthew D Li
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Connie Y Chang
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Mohamed Jarraya
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Oluwaseun Akeju
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Andrew Schrepf
- Chronic Pain and Fatigue Research Center, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
| | - Richard E Harris
- Susan Samueli Integrative Health Institute, School of Medicine, University of California at Irvine, Irvine CA, United States
- Department of Anesthesiology and Perioperative Care, School of Medicine, University of California at Irvine, Irvine CA, United States
- Chronic Pain and Fatigue Research Center, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
| | - Young-Min Kwon
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Hany Bedair
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Antonia F Chen
- Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, MA, United States
| | - Nathaniel D Mercaldo
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Norman Kettner
- Department of Radiology, Logan University, Chesterfield, MO, United States
| | - Vitaly Napadow
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
- Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Nicola Toschi
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Biomedicine and Prevention, University of Rome, "Tor Vergata," Rome, Italy
| | - Robert R Edwards
- Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - Marco L Loggia
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
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Lepiarz-Raba I, Hidayat T, Hannan AJ, Jawaid A. Potential Alzheimer's disease drug targets identified through microglial biology research. Expert Opin Drug Discov 2024; 19:587-602. [PMID: 38590098 DOI: 10.1080/17460441.2024.2335210] [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: 01/20/2024] [Accepted: 03/22/2024] [Indexed: 04/10/2024]
Abstract
INTRODUCTION Microglia, the primary immune cells in the brain, play multifaceted roles in Alzheimer's disease (AD). Microglia can potentially mitigate the pathological progression of AD by clearing amyloid beta (Aβ) deposits in the brain and through neurotrophic support. In contrast, disproportionate activation of microglial pro-inflammatory pathways, as well as excessive elimination of healthy synapses, can exacerbate neurodegeneration in AD. The challenge, therefore, lies in discerning the precise regulation of the contrasting microglial properties to harness their therapeutic potential in AD. AREAS COVERED This review examines the evidence relevant to the disease-modifying effects of microglial manipulators in AD preclinical models. The deleterious pro-inflammatory effects of microglia in AD can be ameliorated via direct suppression or indirectly through metabolic manipulation, epigenetic targeting, and modulation of the gut-brain axis. Furthermore, microglial clearance of Aβ deposits in AD can be enhanced via strategically targeting microglial membrane receptors, lysosomal functions, and metabolism. EXPERT OPINION Given the intricate and diverse nature of microglial responses throughout the course of AD, therapeutic interventions directed at microglia warrant a tactical approach. This could entail employing therapeutic regimens, which concomitantly suppress pro-inflammatory microglial responses while selectively enhancing Aβ phagocytosis.
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Affiliation(s)
- Izabela Lepiarz-Raba
- Laboratory for Translational Research in Exposures and Neuropsychiatric Disorders (TREND), Braincity: Center of Excellence for Neural Plasticity and Brain Disorders, Nencki Institute of Experimental Biology, Warsaw, Poland
| | - Taufik Hidayat
- Laboratory for Translational Research in Exposures and Neuropsychiatric Disorders (TREND), Braincity: Center of Excellence for Neural Plasticity and Brain Disorders, Nencki Institute of Experimental Biology, Warsaw, Poland
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia
| | - Ali Jawaid
- Laboratory for Translational Research in Exposures and Neuropsychiatric Disorders (TREND), Braincity: Center of Excellence for Neural Plasticity and Brain Disorders, Nencki Institute of Experimental Biology, Warsaw, Poland
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Singh SB, Bhandari S, Bhandari S, Bhandari S, Singh R, Raynor WY, Hess S, Werner TJ, Alavi A, Revheim ME. Role of PET/CT in diagnosing and monitoring disease activity in rheumatoid arthritis: a review. Ann Nucl Med 2024; 38:165-175. [PMID: 38277115 PMCID: PMC10884090 DOI: 10.1007/s12149-023-01896-z] [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: 10/15/2023] [Accepted: 12/22/2023] [Indexed: 01/27/2024]
Abstract
Rheumatoid Arthritis (RA) is a systemic inflammatory disorder that commonly presents with polyarthritis but can have multisystemic involvement and complications, leading to increased morbidity and mortality. The diagnosis of RA continues to be challenging due to its varied clinical presentations. In this review article, we aim to determine the potential of PET/CT to assist in the diagnosis of RA and its complications, evaluate the therapeutic response to treatment, and predict RA remission. PET/CT has increasingly been used in the last decade to diagnose, monitor treatment response, predict remissions, and diagnose subclinical complications in RA. PET imaging with [18F]-fluorodeoxyglucose ([18F]-FDG) is the most commonly applied radiotracer in RA, but other tracers are also being studied. PET/CT with [18F]-FDG, [18F]-NaF, and other tracers might lead to early identification of RA and timely evidence-based clinical management, decreasing morbidity and mortality. Although PET/CT has been evolving as a promising tool for evaluating and managing RA, more evidence is required before incorporating PET/CT in the standard clinical management of RA.
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Affiliation(s)
- Shashi B Singh
- Department of Radiology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Sambhawana Bhandari
- Department of Medicine, Division of Rheumatology, Washington University in St Louis, St Louis, MO, USA
| | | | | | | | - William Y Raynor
- Department of Radiology, Rutgers Robert Wood Johnson Medical School, 1 Robert Wood Johnson Place, MEB#404, New Brunswick, NJ, 08901, USA
| | - Soren Hess
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Thomas J Werner
- Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Abass Alavi
- Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Mona-Elisabeth Revheim
- The Intervention Center, Division of Technology and Innovation, Oslo University Hospital, Rikshospitalet, Nydalen, Post Box 4950, 0424, Oslo, Norway.
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Blindern, Post Box 1078, 0316, Oslo, Norway.
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Wongso H, Kurniawan A, Setiadi Y, Kusumaningrum CE, Widyasari EM, Wibawa TH, Mahendra I, Febrian MB, Sriyani ME, Halimah I, Daruwati I, Gunawan R, Achmad A, Nugraha DH, Lesmana R, Nugraha AS. Translocator Protein 18 kDa (TSPO): A Promising Molecular Target for Image-Guided Surgery of Solid Cancers. Adv Pharm Bull 2024; 14:86-104. [PMID: 38585455 PMCID: PMC10997928 DOI: 10.34172/apb.2024.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/26/2023] [Accepted: 10/08/2023] [Indexed: 04/09/2024] Open
Abstract
The translocator protein 18-kDa (TSPO) is a mitochondrial membrane protein that is previously identified as the peripheral benzodiazepine receptor (PBR). Furthermore, it plays a significant role in a diverse range of biochemical processes, including steroidogenesis, mitochondrial cholesterol transport, cell survival and death, cell proliferation, and carcinogenesis. Several investigations also reported its roles in various types of cancers, including colorectal, brain, breast, prostate, and lung cancers, as well as melanoma. According to a previous study, the expression of TSPO was upregulated in cancer cells, which corresponds to an aggressive phenotype and/or poor prognosis. Consequently, the potential for crafting diagnostic and prognostic tools with a focus on TSPO holds great potential. In this context, several radioligands designed to target this protein have been identified, and some of the candidates have advanced to clinical trials. In recent years, the use of hybrid probes with radioactive and fluorescence molecules for image-guided surgery has exhibited promising results in animal and human studies. This indicates that the approach can serve as a valuable surgical navigator during cancer surgery. The current hybrid probes are built from various molecular platforms, including small molecules, nanoparticles, and antibodies. Although several TSPO-targeted imaging probes have been developed, their development for image-guided surgery of cancers is still limited. Therefore, this review aims to highlight recent findings on the involvement of TSPO in carcinogenesis, as well as provide a new perspective on the potential application of TSPO-targeted hybrid probes for image-guided surgery.
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Affiliation(s)
- Hendris Wongso
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
| | - Ahmad Kurniawan
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Yanuar Setiadi
- Research Center for Environmental and Clean Technology, Research Organization for Life Sciences and Environment, National Research and Innovation Agency, Puspiptek, Banten 15314, Indonesia
| | - Crhisterra E. Kusumaningrum
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Eva M. Widyasari
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Teguh H.A. Wibawa
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Isa Mahendra
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
| | - Muhamad B. Febrian
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Maula E. Sriyani
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Iim Halimah
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
| | - Isti Daruwati
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Universitas Padjadjaran, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
| | - Rudi Gunawan
- Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency Republic of Indonesia, Puspiptek, Banten 15314, Indonesia
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Universitas Padjadjaran, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
| | - Arifudin Achmad
- Research Collaboration Center for Theranostic Radiopharmaceuticals, National Research and Innovation Agency, Jl. Ir. Soekarno KM 21, Jatinangor 45363, Indonesia
- Department of Nuclear Medicine and Molecular Theranostics, Faculty of Medicine, Universitas Padjadjaran, Bandung 40161
- Oncology and Stem Cells Working Group, Faculty of Medicine, Universitas Padjadjaran, Bandung 40161
| | | | - Ronny Lesmana
- Department of Biomedical Science, Faculty of Medicine, Universitas Padjadjaran, Jatinangor 45363, Indonesia
- Physiology Molecular, Division of Biological Activity, Central Laboratory, Universitas Padjadjaran, Jatinangor 45363, Indonesia
- Laboratory of Sciences, Graduate School, Universitas Padjadjaran, Bandung, Indonesia
| | - Ari S. Nugraha
- Drug Utilisation and Discovery Research Group, Faculty of Pharmacy, Universitas Jember, Jember 68121, Indonesia
- School of Chemistry and Molecular Biosciences, Molecular Horizons, University of Wollongong, Wollongong, New South Wales, 2522, Australia
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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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10
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Zhou J, Yang C, Xv Q, Wang L, Shen L, Lv Q. Usefulness of Serum Translocator Protein as a Potential Predictive Biochemical Marker of Three-Month Cognitive Impairment After Acute Intracerebral Hemorrhage: A Prospective Observational Cohort Study. Int J Gen Med 2023; 16:5389-5403. [PMID: 38021045 PMCID: PMC10674616 DOI: 10.2147/ijgm.s438503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Accepted: 11/08/2023] [Indexed: 12/01/2023] Open
Abstract
Background Translocator protein (TSPO) is a biomarker of neuroinflammation and brain injury. This study aimed to ascertain the potential of serum TSPO as a predictor of cognitive impairment after acute intracerebral hemorrhage (ICH). Methods In this prospective observational cohort study, 276 patients with supratentorial ICH were randomly assigned to two groups (184 patients in the study group and 92 in the validation group) in a 2:1 ratio. Serum TSPO levels were gauged at admission, and cognitive status was assessed using the Montreal Cognitive Assessment Scale (MoCA) post-stroke 3 months. A MoCA score of < 26 was considered indicative of cognitive impairment. Results Serum TSPO levels were inversely correlated with MoCA scores (ρ=-0.592; P<0.001). Multivariate linear regression analysis showed that serum TSPO levels were independently associated with MoCA scores (β, -0.934; 95% confidence interval (CI), -1.412--0.455; VIF, 1.473; P<0.001). Serum TSPO levels were substantially higher in patients with cognitive impairment than in the remaining patients (median, 2.7 versus 1.6 ng/mL; P<0.001). Serum TSPO levels were linearly correlated with the risk of cognitive impairment under a restricted cubic spline (P=0.325) and independently predicted cognitive impairment (odds ratio, 1.589; 95% CI, 1.139-2.216; P=0.016). Subgroup analysis showed that the relationship between serum TSPO levels and cognitive impairment was not markedly influenced by other parameters, such as age, sex, drinking, smoking, hypertension, diabetes mellitus, body mass index, and dyslipidemia (all P for interaction > 0.05). The model, which contained serum TSPO, National Institutes of Health Stroke Scale scores and hematoma volume, performed well under the receiver operating characteristic curve, calibration curve and decision curve, and using the Hosmer-Lemeshow test. This model was validated in the validation group. Conclusion Serum TSPO level upon admission after ICH was independently associated with cognitive impairment, substantializing serum TSPO as a reliable predictor of post-ICH cognitive impairment.
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Affiliation(s)
- Jing Zhou
- Department of Neurosurgery, Shengzhou People’s Hospital (the First Affiliated Hospital of Zhejiang University Shengzhou Branch), Shengzhou, Zhejiang, People’s Republic of China
| | - Chunsong Yang
- Department of Neurosurgery, Shengzhou People’s Hospital (the First Affiliated Hospital of Zhejiang University Shengzhou Branch), Shengzhou, Zhejiang, People’s Republic of China
| | - Qichen Xv
- Department of Neurosurgery, Shengzhou People’s Hospital (the First Affiliated Hospital of Zhejiang University Shengzhou Branch), Shengzhou, Zhejiang, People’s Republic of China
| | - Liyun Wang
- Department of Neurosurgery, Shengzhou People’s Hospital (the First Affiliated Hospital of Zhejiang University Shengzhou Branch), Shengzhou, Zhejiang, People’s Republic of China
| | - Liangjun Shen
- Department of Neurosurgery, Shengzhou People’s Hospital (the First Affiliated Hospital of Zhejiang University Shengzhou Branch), Shengzhou, Zhejiang, People’s Republic of China
| | - Qingwei Lv
- Department of Neurosurgery, Shengzhou People’s Hospital (the First Affiliated Hospital of Zhejiang University Shengzhou Branch), Shengzhou, Zhejiang, People’s Republic of China
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11
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Loveland PM, Yu JJ, Churilov L, Yassi N, Watson R. Investigation of Inflammation in Lewy Body Dementia: A Systematic Scoping Review. Int J Mol Sci 2023; 24:12116. [PMID: 37569491 PMCID: PMC10418754 DOI: 10.3390/ijms241512116] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/24/2023] [Accepted: 07/26/2023] [Indexed: 08/13/2023] Open
Abstract
Inflammatory mechanisms are increasingly recognized as important contributors to the pathogenesis of neurodegenerative diseases, including Lewy body dementia (LBD). Our objectives were to, firstly, review inflammation investigation methods in LBD (dementia with Lewy bodies and Parkinson's disease dementia) and, secondly, identify alterations in inflammatory signals in LBD compared to people without neurodegenerative disease and other neurodegenerative diseases. A systematic scoping review was performed by searching major electronic databases (MEDLINE, Embase, Web of Science, and PSYCHInfo) to identify relevant human studies. Of the 2509 results screened, 80 studies were included. Thirty-six studies analyzed postmortem brain tissue, and 44 investigated living subjects with cerebrospinal fluid, blood, and/or brain imaging assessments. Largely cross-sectional data were available, although two longitudinal clinical studies investigated prodromal Lewy body disease. Investigations were focused on inflammatory immune cell activity (microglia, astrocytes, and lymphocytes) and inflammatory molecules (cytokines, etc.). Results of the included studies identified innate and adaptive immune system contributions to inflammation associated with Lewy body pathology and clinical disease features. Different signals in early and late-stage disease, with possible late immune senescence and dystrophic glial cell populations, were identified. The strength of these associations is limited by the varying methodologies, small study sizes, and cross-sectional nature of the data. Longitudinal studies investigating associations with clinical and other biomarker outcomes are needed to improve understanding of inflammatory activity over the course of LBD. This could identify markers of disease activity and support therapeutic development.
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Affiliation(s)
- Paula M. Loveland
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville 3000, Australia
- Department of Medicine, The Royal Melbourne Hospital, University of Melbourne, Parkville 3000, Australia
| | - Jenny J. Yu
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville 3000, Australia
- Department of Medicine, The Royal Melbourne Hospital, University of Melbourne, Parkville 3000, Australia
| | - Leonid Churilov
- Department of Neurology, Melbourne Brain Centre, The Royal Melbourne Hospital, University of Melbourne, Parkville 3000, Australia
- Melbourne Medical School, University of Melbourne, Parkville 3000, Australia
| | - Nawaf Yassi
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville 3000, Australia
- Department of Medicine, The Royal Melbourne Hospital, University of Melbourne, Parkville 3000, Australia
- Department of Neurology, Melbourne Brain Centre, The Royal Melbourne Hospital, University of Melbourne, Parkville 3000, Australia
| | - Rosie Watson
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville 3000, Australia
- Department of Medicine, The Royal Melbourne Hospital, University of Melbourne, Parkville 3000, Australia
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12
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Isik S, Yeman Kiyak B, Akbayir R, Seyhali R, Arpaci T. Microglia Mediated Neuroinflammation in Parkinson’s Disease. Cells 2023; 12:cells12071012. [PMID: 37048085 PMCID: PMC10093562 DOI: 10.3390/cells12071012] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/16/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023] Open
Abstract
Parkinson’s Disease (PD) is the second most common neurodegenerative disorder seen, especially in the elderly. Tremor, shaking, movement problems, and difficulty with balance and coordination are among the hallmarks, and dopaminergic neuronal loss in substantia nigra pars compacta of the brain and aggregation of intracellular protein α-synuclein are the pathological characterizations. Neuroinflammation has emerged as an involving mechanism at the initiation and development of PD. It is a complex network of interactions comprising immune and non-immune cells in addition to mediators of the immune response. Microglia, the resident macrophages in the CNS, take on the leading role in regulating neuroinflammation and maintaining homeostasis. Under normal physiological conditions, they exist as “homeostatic” but upon pathological stimuli, they switch to the “reactive state”. Pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes are used to classify microglial activity with each phenotype having its own markers and released mediators. When M1 microglia are persistent, they will contribute to various inflammatory diseases, including neurodegenerative diseases, such as PD. In this review, we focus on the role of microglia mediated neuroinflammation in PD and also signaling pathways, receptors, and mediators involved in the process, presenting the studies that associate microglia-mediated inflammation with PD. A better understanding of this complex network and interactions is important in seeking new therapies for PD and possibly other neurodegenerative diseases.
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Affiliation(s)
- Sevim Isik
- Department of Molecular Biology and Genetics, Faculty of Engineering and Natural Sciences, Uskudar University, Uskudar, Istanbul 34662, Turkey
- Stem Cell Research and Application Center (USKOKMER), Uskudar University, Uskudar, Istanbul 34662, Turkey
- Correspondence: ; Tel.: +90-216-400-2222 (ext. 2462)
| | - Bercem Yeman Kiyak
- Stem Cell Research and Application Center (USKOKMER), Uskudar University, Uskudar, Istanbul 34662, Turkey
- Department of Molecular Medicine, Institute of Hamidiye Health Sciences, University of Health Sciences, Uskudar, Istanbul 34668, Turkey
| | - Rumeysa Akbayir
- Stem Cell Research and Application Center (USKOKMER), Uskudar University, Uskudar, Istanbul 34662, Turkey
- Department of Molecular Biology, Institute of Science, Uskudar University, Uskudar, Istanbul 34662, Turkey
| | - Rama Seyhali
- Stem Cell Research and Application Center (USKOKMER), Uskudar University, Uskudar, Istanbul 34662, Turkey
- Department of Molecular Biology, Institute of Science, Uskudar University, Uskudar, Istanbul 34662, Turkey
| | - Tahire Arpaci
- Stem Cell Research and Application Center (USKOKMER), Uskudar University, Uskudar, Istanbul 34662, Turkey
- Department of Molecular Biology, Institute of Science, Uskudar University, Uskudar, Istanbul 34662, Turkey
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13
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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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14
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Diaz-Galvan P, Miyagawa T, Przybelski SA, Lesnick TG, Senjem ML, Jack CR, Forsberg LK, Min HK, St. Louis EK, Savica R, Fields JA, Benarroch EE, Lowe V, Petersen RC, Boeve BF, Kantarci K. Brain glucose metabolism and nigrostriatal degeneration in isolated rapid eye movement sleep behaviour disorder. Brain Commun 2023; 5:fcad021. [PMID: 36844148 PMCID: PMC9945851 DOI: 10.1093/braincomms/fcad021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 11/14/2022] [Accepted: 01/31/2023] [Indexed: 02/04/2023] Open
Abstract
Alterations of cerebral glucose metabolism can be detected in patients with isolated rapid eye movement sleep behaviour disorder, a prodromal feature of neurodegenerative diseases with α-synuclein pathology. However, metabolic characteristics that determine clinical progression in isolated rapid eye movement sleep behaviour disorder and their association with other biomarkers need to be elucidated. We investigated the pattern of cerebral glucose metabolism on 18F-fluorodeoxyglucose PET in patients with isolated rapid eye movement sleep behaviour disorder, differentiating between those who clinically progressed and those who remained stable over time. Second, we studied the association between 18F-fluorodeoxyglucose PET and lower dopamine transporter availability in the putamen, another hallmark of synucleinopathies. Patients with isolated rapid eye movement sleep behaviour disorder from the Mayo Clinic Alzheimer's Disease Research Center and Center for Sleep Medicine (n = 22) and age-and sex-matched clinically unimpaired controls (clinically unimpaired; n = 44) from the Mayo Clinic Study of Aging were included. All participants underwent 18F-fluorodeoxyglucose PET and dopamine transporter imaging with iodine 123-radiolabeled 2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane on single-photon emission computerized tomography. A subset of patients with isolated rapid eye movement sleep behaviour disorder with follow-up evaluations (n = 17) was classified as isolated rapid eye movement sleep behaviour disorder progressors (n = 7) if they developed mild cognitive impairment or Parkinson's disease; or isolated rapid eye movement sleep behaviour disorder stables (n = 10) if they remained with a diagnosis of isolated rapid eye movement sleep behaviour disorder with no cognitive impairment. Glucose metabolic abnormalities in isolated rapid eye movement sleep behaviour disorder were determined by comparing atlas-based regional 18F-fluorodeoxyglucose PET uptake between isolated rapid eye movement sleep behaviour disorder and clinically unimpaired. Associations between 18F-fluorodeoxyglucose PET and dopamine transporter availability in the putamen were analyzed with Pearson's correlation within the nigrostriatal pathway structures and with voxel-based analysis in the cortex. Patients with isolated rapid eye movement sleep behaviour disorder had lower glucose metabolism in the substantia nigra, retrosplenial cortex, angular cortex, and thalamus, and higher metabolism in the amygdala and entorhinal cortex compared with clinically unimpaired. Patients with isolated rapid eye movement sleep behaviour disorder who clinically progressed over time were characterized by higher glucose metabolism in the amygdala and entorhinal cortex, and lower glucose metabolism in the cerebellum compared with clinically unimpaired. Lower dopamine transporter availability in the putamen was associated with higher glucose metabolism in the pallidum within the nigrostriatal pathway; and with higher 18F-fluorodeoxyglucose uptake in the amygdala, insula, and temporal pole on a voxel-based analysis, although these associations did not survive after correcting for multiple comparisons. Our findings suggest that cerebral glucose metabolism in isolated rapid eye movement sleep behaviour disorder is characterized by hypometabolism in regions frequently affected during the prodromal stage of synucleinopathies, potentially reflecting synaptic dysfunction. Hypermetabolism is also seen in isolated rapid eye movement sleep behaviour disorder, suggesting that synaptic metabolic disruptions may be leading to a lack of inhibition, compensatory mechanisms, or microglial activation, especially in regions associated with nigrostriatal degeneration.
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Affiliation(s)
| | - Toji Miyagawa
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Scott A Przybelski
- Department of Quantitative Health Science, Mayo Clinic, Rochester, MN 55905, USA
| | - Timothy G Lesnick
- Department of Quantitative Health Science, Mayo Clinic, Rochester, MN 55905, USA
| | - Matthew L Senjem
- Department of Information Technology, Mayo Clinic, Rochester, MN 55905, USA
| | - Clifford R Jack
- Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA
| | - Leah K Forsberg
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Hoon-Ki Min
- Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA
| | | | - Rodolfo Savica
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Julie A Fields
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, MN 55905, USA
| | | | - Val Lowe
- Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA
| | | | - Bradley F Boeve
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Kejal Kantarci
- Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA
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15
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Corsi F, Baglini E, Barresi E, Salerno S, Cerri C, Martini C, Da Settimo Passetti F, Taliani S, Gargini C, Piano I. Targeting TSPO Reduces Inflammation and Apoptosis in an In Vitro Photoreceptor-Like Model of Retinal Degeneration. ACS Chem Neurosci 2022; 13:3188-3197. [PMID: 36300862 PMCID: PMC9673150 DOI: 10.1021/acschemneuro.2c00582] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The 18 kDa translocator protein (TSPO) is predominantly located in the mitochondrial outer membrane, playing an important role in steroidogenesis, inflammation, survival, and cell proliferation. Its expression in the CNS, and mainly in glial cells, is upregulated in neuropathologies and brain injury. In this study, the potential of targeting TSPO for the therapeutic treatment of inflammatory-based retinal neurodegeneration was evaluated by means of an in vitro model of lipopolysaccharide (LPS)-induced degeneration in 661 W cells, a photoreceptor-like cell line. After the assessment of the expression of TSPO in 661W cells, which, to the best of our knowledge, was never investigated so far, the anti-inflammatory and cytoprotective effects of a number of known TSPO ligands, belonging to the class of N,N-dialkyl-2-arylindol-3-ylglyoxylamides (PIGAs), were evaluated, using the classic TSPO ligand PK11195 as the reference standard. All tested PIGAs showed the ability to modulate the inflammatory and apoptotic processes in 661 W photoreceptor-like cells and to reduce LPS-driven cellular cytotoxicity. The protective effect of PIGAs was, in all cases, reduced by cotreatment with the pregnenolone synthesis inhibitor SU-10603, suggesting the involvement of neurosteroids in the protective mechanism. As inflammatory processes play a crucial role in the retinal neurodegenerative disease progression toward photoreceptors' death and complete blindness, targeting TSPO might represent a successful strategy to slow down this degenerative process that may lead to the inexorable loss of vision.
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16
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Foray C, Barca C, Winkeler A, Wagner S, Hermann S, Schäfers M, Grauer OM, Zinnhardt B, Jacobs AH. Interrogating Glioma-Associated Microglia and Macrophage Dynamics Under CSF-1R Therapy with Multitracer In Vivo PET/MRI. J Nucl Med 2022; 63:1386-1393. [PMID: 35115369 PMCID: PMC9454459 DOI: 10.2967/jnumed.121.263318] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 01/04/2022] [Indexed: 01/26/2023] Open
Abstract
Glioma-associated microglia and macrophages (GAMMs) are key players in creating an immunosuppressive microenvironment. They can be efficiently targeted by inhibiting the colony-stimulating factor 1 receptor (CSF-1R). We applied noninvasive PET/CT and PET/MRI using 18F-fluoroethyltyrosine (18F-FET) (amino acid metabolism) and N,N-diethyl-2-[4-(2-18F-fluoroethoxy)phenyl]-5,7-dimethylpyrazolo[1,5-a]pyrimidine-3-acetamide (18F-DPA-714) (translocator protein) to understand the role of GAMMs in glioma initiation, monitor in vivo therapy-induced GAMM depletion, and observe GAMM repopulation after drug withdrawal. Methods: C57BL/6 mice (n = 44) orthotopically implanted with syngeneic mouse GL261 glioma cells were treated with different regimens using the CSF-1R inhibitor PLX5622 (6-fluoro-N-((5-fluoro-2-methoxypyridin-3-yl)methyl)-5-((5-methyl-1H-pyrrolo[2,3-b]pyridin-3-yl)methyl)pyridin-2-amine) or vehicle, establishing a preconditioning model and a repopulation model, respectively. The mice underwent longitudinal PET/CT and PET/MRI. Results: The preconditioning model indicated similar tumor growth based on MRI (44.5% ± 24.8%), 18F-FET PET (18.3% ± 11.3%), and 18F-DPA-714 PET (16% ± 19.04%) volume dynamics in all groups, suggesting that GAMMs are not involved in glioma initiation. The repopulation model showed significantly reduced 18F-DPA-714 uptake (-45.6% ± 18.4%), significantly reduced GAMM infiltration even after repopulation, and a significantly decreased tumor volume (-54.29% ± 8.6%) with repopulation as measured by MRI, supported by a significant reduction in 18F-FET uptake (-50.2% ± 5.3%). Conclusion: 18F-FET and 18F-DPA-714 PET/MRI allow noninvasive assessment of glioma growth under various regimens of CSF-1R therapy. CSF-1R-mediated modulation of GAMMs may be of high interest as therapy or cotherapy against glioma.
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Affiliation(s)
- Claudia Foray
- European Institute for Molecular Imaging, University of Münster, Münster, Germany; .,PET Imaging in Drug Design and Development, Münster, Germany
| | - Cristina Barca
- European Institute for Molecular Imaging, University of Münster, Münster, Germany;,PET Imaging in Drug Design and Development, Münster, Germany
| | | | - Stefan Wagner
- Department of Nuclear Medicine, University Hospital Münster, Münster, Germany
| | - Sven Hermann
- European Institute for Molecular Imaging, University of Münster, Münster, Germany
| | - Michael Schäfers
- European Institute for Molecular Imaging, University of Münster, Münster, Germany;,Department of Nuclear Medicine, University Hospital Münster, Münster, Germany
| | - Oliver M. Grauer
- Department of Neurology, University Hospital Münster, Münster, Germany
| | - Bastian Zinnhardt
- European Institute for Molecular Imaging, University of Münster, Münster, Germany;,PET Imaging in Drug Design and Development, Münster, Germany;,Department of Nuclear Medicine, University Hospital Münster, Münster, Germany;,Biomarkers and Translational Technologies, Neurosciences and Rare Diseases, Pharma Research and Early Development, F. Hoffmann-La Roche Ltd., Basel, Switzerland; and
| | - Andreas H. Jacobs
- European Institute for Molecular Imaging, University of Münster, Münster, Germany;,PET Imaging in Drug Design and Development, Münster, Germany;,Department of Geriatrics with Neurology, Johanniter Hospital, and Centre for Integrated Oncology of the University Hospital Bonn, Bonn, Germany
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17
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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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Park J, Barahona‐Torres N, Jang S, Mok KY, Kim HJ, Han S, Cho K, Zhou X, Fu AKY, Ip NY, Seo J, Choi M, Jeong H, Hwang D, Lee DY, Byun MS, Yi D, Han JW, Mook‐Jung I, Hardy J. Multi-Omics-Based Autophagy-Related Untypical Subtypes in Patients with Cerebral Amyloid Pathology. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2201212. [PMID: 35694866 PMCID: PMC9376815 DOI: 10.1002/advs.202201212] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/26/2022] [Indexed: 05/05/2023]
Abstract
Recent multi-omics analyses paved the way for a comprehensive understanding of pathological processes. However, only few studies have explored Alzheimer's disease (AD) despite the possibility of biological subtypes within these patients. For this study, unsupervised classification of four datasets (genetics, miRNA transcriptomics, proteomics, and blood-based biomarkers) using Multi-Omics Factor Analysis+ (MOFA+), along with systems-biological approaches following various downstream analyses are performed. New subgroups within 170 patients with cerebral amyloid pathology (Aβ+) are revealed and the features of them are identified based on the top-rated targets constructing multi-omics factors of both whole (M-TPAD) and immune-focused models (M-IPAD). The authors explored the characteristics of subtypes and possible key-drivers for AD pathogenesis. Further in-depth studies showed that these subtypes are associated with longitudinal brain changes and autophagy pathways are main contributors. The significance of autophagy or clustering tendency is validated in peripheral blood mononuclear cells (PBMCs; n = 120 including 30 Aβ- and 90 Aβ+), induced pluripotent stem cell-derived human brain organoids/microglia (n = 12 including 5 Aβ-, 5 Aβ+, and CRISPR-Cas9 apolipoprotein isogenic lines), and human brain transcriptome (n = 78). Collectively, this study provides a strategy for precision medicine therapy and drug development for AD using integrative multi-omics analysis and network modelling.
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Affiliation(s)
- Jong‐Chan Park
- Department of Neurodegenerative DiseaseUCL Queen Square Institute of NeurologyUniversity College LondonLondonWC1N 3BGUK
- Department of Biochemistry and Biomedical SciencesCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
- Neuroscience Research InstituteMedical Research CenterCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
- SNU Korea Dementia Research CenterCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
| | - Natalia Barahona‐Torres
- Department of Neurodegenerative DiseaseUCL Queen Square Institute of NeurologyUniversity College LondonLondonWC1N 3BGUK
| | - So‐Yeong Jang
- Department of Bio and Brain EngineeringKorea Advanced Institute of Science and TechnologyDaejeon34141Republic of Korea
| | - Kin Y. Mok
- Department of Neurodegenerative DiseaseUCL Queen Square Institute of NeurologyUniversity College LondonLondonWC1N 3BGUK
| | - Haeng Jun Kim
- Department of Biochemistry and Biomedical SciencesCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
- SNU Korea Dementia Research CenterCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
| | - Sun‐Ho Han
- Department of Biochemistry and Biomedical SciencesCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
- Neuroscience Research InstituteMedical Research CenterCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
- SNU Korea Dementia Research CenterCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
| | - Kwang‐Hyun Cho
- Department of Bio and Brain EngineeringKorea Advanced Institute of Science and TechnologyDaejeon34141Republic of Korea
| | - Xiaopu Zhou
- Division of Life ScienceState Key Laboratory of Molecular NeuroscienceMolecular Neuroscience CenterThe Hong Kong University of Science and TechnologyClear Water Bay, KowloonHong Kong999077China
- Hong Kong Center for Neurodegenerative DiseasesHong Kong Science ParkHong Kong999077China
- Guangdong Provincial Key Laboratory of Brain ScienceDisease and Drug DevelopmentHKUST Shenzhen Research InstituteShenzhen‐Hong Kong Institute of Brain ScienceShenzhenGuangdong518057China
| | - Amy K. Y. Fu
- Division of Life ScienceState Key Laboratory of Molecular NeuroscienceMolecular Neuroscience CenterThe Hong Kong University of Science and TechnologyClear Water Bay, KowloonHong Kong999077China
- Hong Kong Center for Neurodegenerative DiseasesHong Kong Science ParkHong Kong999077China
- Guangdong Provincial Key Laboratory of Brain ScienceDisease and Drug DevelopmentHKUST Shenzhen Research InstituteShenzhen‐Hong Kong Institute of Brain ScienceShenzhenGuangdong518057China
| | - Nancy Y. Ip
- Division of Life ScienceState Key Laboratory of Molecular NeuroscienceMolecular Neuroscience CenterThe Hong Kong University of Science and TechnologyClear Water Bay, KowloonHong Kong999077China
- Hong Kong Center for Neurodegenerative DiseasesHong Kong Science ParkHong Kong999077China
- Guangdong Provincial Key Laboratory of Brain ScienceDisease and Drug DevelopmentHKUST Shenzhen Research InstituteShenzhen‐Hong Kong Institute of Brain ScienceShenzhenGuangdong518057China
| | - Jieun Seo
- Department of Laboratory MedicineSeverance HospitalYonsei University College of MedicineSeoul03722Republic of Korea
| | - Murim Choi
- Department of Biochemistry and Biomedical SciencesCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
| | - Hyobin Jeong
- European Molecular Biology LaboratoryGenome Biology UnitHeidelberg69117Germany
| | - Daehee Hwang
- Department of Biological SciencesSeoul National UniversitySeoul08826Republic of Korea
| | - Dong Young Lee
- Institute of Human Behavioral MedicineMedical Research CenterSeoul National UniversitySeoul03080Republic of Korea
- Department of PsychiatryCollege of medicineSeoul National UniversitySeoul03080Republic of Korea
- Department of NeuropsychiatrySeoul National University HospitalSeoul03080Republic of Korea
| | - Min Soo Byun
- Department of PsychiatryPusan National University Yangsan HospitalYangsan50612Republic of Korea
| | - Dahyun Yi
- Biomedical Research InstituteSeoul National University HospitalSeoul03082Republic of Korea
| | - Jong Won Han
- Department of Biochemistry and Biomedical SciencesCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
| | - Inhee Mook‐Jung
- Department of Biochemistry and Biomedical SciencesCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
- Neuroscience Research InstituteMedical Research CenterCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
- SNU Korea Dementia Research CenterCollege of MedicineSeoul National UniversitySeoul03080Republic of Korea
| | - John Hardy
- Department of Neurodegenerative DiseaseUCL Queen Square Institute of NeurologyUniversity College LondonLondonWC1N 3BGUK
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MicroPET Imaging Assessment of Brain Tau and Amyloid Deposition in 6 × Tg Alzheimer’s Disease Model Mice. Int J Mol Sci 2022; 23:ijms23105485. [PMID: 35628296 PMCID: PMC9146140 DOI: 10.3390/ijms23105485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/04/2022] [Accepted: 05/09/2022] [Indexed: 11/23/2022] Open
Abstract
Alzheimer’s disease (AD) is characterized by the deposition of extracellular amyloid plaques and intracellular accumulation of neurofibrillary tangles (NFT). Amyloid beta (Aβ) and tau imaging are widely used for diagnosing and monitoring AD in clinical settings. We evaluated the pathology of a recently developed 6 × Tg − AD (6 × Tg) mouse model by crossbreeding 5 × FAD mice with mice expressing mutant (P301L) tau protein using micro-positron emission tomography (PET) image analysis. PET studies were performed in these 6 × Tg mice using [18F]Flutemetamol, which is an amyloid PET radiotracer; [18F]THK5351 and [18F]MK6240, which are tau PET radiotracers; moreover, [18F]DPA714, which is a translocator protein (TSPO) radiotracer, and comparisons were made with age-matched mice of their respective parental strains. We compared group differences in standardized uptake value ratio (SUVR), kinetic parameters, biodistribution, and histopathology. [18F]Flutemetamol images showed prominent cortical uptake and matched well with 6E10 staining images from 2-month-old 6 × Tg mice. [18F]Flutemetamol images showed a significant correlation with [18F]DPA714 in the cortex and hippocampus. [18F]THK5351 images revealed prominent hippocampal uptake and matched well with AT8 immunostaining images in 4-month-old 6 × Tg mice. Moreover, [18F]THK5351 images were confirmed using [18F]MK6240, which revealed significant correlations in the cortex and hippocampus. Uptake of [18F]THK5351 or [18F]MK6240 was highly correlated with [18F]Flutemetamol in 4-month-old 6 × Tg mice. In conclusion, PET imaging revealed significant age-related uptake of Aβ, tau, and TSPO in 6 × Tg mice, which was highly correlated with age-dependent pathology.
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Zhang Q, Li Q, Liu S, Zheng H, Ji L, Yi N, Bao W, Zhu X, Sun W, Liu X, Zhang S, Zuo C, Li Y, Xiong Q, Lu B. Glucagon-like peptide-1 receptor agonist attenuates diabetic neuropathic pain via inhibition of NOD-like receptor protein 3 inflammasome in brain microglia. Diabetes Res Clin Pract 2022; 186:109806. [PMID: 35240228 DOI: 10.1016/j.diabres.2022.109806] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 02/24/2022] [Indexed: 12/26/2022]
Abstract
AIMS We aimed to explore the evidence of brain microglia activation in diabetic neuropathic pain (DNP) and the effect and mechanism of glucagon-like peptide-1 receptor agonist (GLP-RA) on DNP via brain microglia. METHODS Brain microglia activation was observed in DNP rats by positron emission tomography/computed tomography. The behavior of neuropathic pain was assessed in DNP rats after intracerebroventricular administration of GLP-1RA or microglial inhibitor minocycline. RNA sequencing was performed to explore the target of GLP-1RA on brain microglia. NOD-like receptor protein 3 (NLRP3) expression in brain microglia was evaluated in mentioned-above DNP rats, and the activation of NLRP3 inflammasome was analyzed in microglia treated with GLP-1RA. RESULTS Microglia were activated in the cortex and thalamus of DNP rats. The thermal and mechanical allodynia were alleviated in DNP rats via intracerebroventricular administration of GLP-1RA or minocycline. And the activation of brain microglia was attenuated in DNP rats by intracerebroventricular administration of GLP-1RA. The expression of NLRP3 in brain microglia, which was found by RNA sequencing, was reduced in DNP rats by administration of GLP-1RA. Furthermore, GLP-1RA attenuated NLRP3 inflammasome activation in microglia triggered by LPS. CONCLUSION GLP-1RA could alleviate DNP, possibly mediated by the suppression of brain microglia NLRP3 inflammasome activation.
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Affiliation(s)
- Qi Zhang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Qingchun Li
- Jing'an District Central Hospital, Fudan University, Jing'an Branch, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Siying Liu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Hangping Zheng
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Lijin Ji
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Na Yi
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Weiqi Bao
- PET Center, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Xiaoming Zhu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Wanwan Sun
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Xiaoxia Liu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Shuo Zhang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Chuantao Zuo
- PET Center, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Yiming Li
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Qian Xiong
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Bin Lu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University, Shanghai 200040, China.
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Wang J, Jin L, Zhang X, Yu H, Ge J, Deng B, Li M, Zuo C, Chen X. Activated microglia by 18F-DPA714 PET in a case of anti-LGI1 autoimmune encephalitis. J Neuroimmunol 2022; 368:577879. [DOI: 10.1016/j.jneuroim.2022.577879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 04/17/2022] [Accepted: 04/19/2022] [Indexed: 11/28/2022]
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22
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Shimochi S, Keller T, Kujala E, Khabbal J, Rajander J, Löyttyniemi E, Solin O, Nuutila P, Kanaya S, Yatkin E, Grönroos TJ, Iida H. Evaluation of [ 18F]F-DPA PET for Detecting Microglial Activation in the Spinal Cord of a Rat Model of Neuropathic Pain. Mol Imaging Biol 2022; 24:641-650. [PMID: 35303205 PMCID: PMC9296394 DOI: 10.1007/s11307-022-01713-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 02/15/2022] [Accepted: 02/18/2022] [Indexed: 12/05/2022]
Abstract
Purpose Recent studies have linked activated spinal glia to neuropathic pain. Here, using a positron emission tomography (PET) scanner with high spatial resolution and sensitivity, we evaluated the feasibility and sensitivity of N,N-diethyl-2-(2-(4-([18F]fluoro)phenyl)-5,7-dimethylpyrazolo[1,5-a] pyrimidin-3-yl)acetamide ([18F]F-DPA) imaging for detecting spinal cord microglial activation after partial sciatic nerve ligation (PSNL) in rats. Procedures Neuropathic pain was induced in rats (n = 20) by PSNL, and pain sensation tests were conducted before surgery and 3 and 7 days post-injury. On day 7, in vivo PET imaging and ex vivo autoradiography were performed using [18F]F-DPA or [11C]PK11195. Ex vivo biodistribution and PET imaging of the removed spinal cord were carried out with [18F]F-DPA. Sham-operated and PK11195-pretreated animals were also examined. Results Mechanical allodynia was confirmed in the PSNL rats from day 3 through day 7. Ex vivo autoradiography showed a higher lesion-to-background uptake with [18F]F-DPA compared with [11C]PK11195. Ex vivo PET imaging of the removed spinal cord showed [18F]F-DPA accumulation in the inflammation site, which was immunohistochemically confirmed to coincide with microglia activation. Pretreatment with PK11195 eliminated the uptake. The SUV values of in vivo [18F]F-DPA and [11C]PK11195 PET were not significantly increased in the lesion compared with the reference region, and were fivefold higher than the values obtained from the ex vivo data. Ex vivo biodistribution revealed a twofold higher [18F]F-DPA uptake in the vertebral body compared to that seen in the bone from the skull. Conclusions [18F]F-DPA aided visualization of the spinal cord inflammation site in PSNL rats on ex vivo autoradiography and was superior to [11C]PK11195. In vivo [18F]F-DPA PET did not allow for visualization of tracer accumulation even using a high-spatial-resolution PET scanner. The main reason for this result was due to insufficient SUVs in the spinal cord region as compared with the background noise, in addition to a spillover from the vertebral body.
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Affiliation(s)
- Saeka Shimochi
- Turku PET Centre, University of Turku, Turku, Finland.,Medicity Research Laboratory, University of Turku, Turku, Finland.,Nara Institute of Science and Technology, Ikoma City, Japan
| | - Thomas Keller
- Turku PET Centre, University of Turku, Turku, Finland
| | - Ella Kujala
- Central Animal Laboratory, University of Turku, Turku, Finland
| | - Joonas Khabbal
- Central Animal Laboratory, University of Turku, Turku, Finland
| | - Johan Rajander
- Accelerator Laboratory, Turku PET Centre, Åbo Akademi University, Turku, Finland
| | | | - Olof Solin
- Turku PET Centre, University of Turku, Turku, Finland.,Accelerator Laboratory, Turku PET Centre, Åbo Akademi University, Turku, Finland
| | - Pirjo Nuutila
- Turku PET Centre, University of Turku, Turku, Finland
| | | | - Emrah Yatkin
- Central Animal Laboratory, University of Turku, Turku, Finland
| | - Tove J Grönroos
- Turku PET Centre, University of Turku, Turku, Finland.,Medicity Research Laboratory, University of Turku, Turku, Finland
| | - Hidehiro Iida
- Turku PET Centre, University of Turku, Turku, Finland. .,Nara Institute of Science and Technology, Ikoma City, Japan. .,Turku PET Centre, Turku University Hospital, Turku, Finland.
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PET Imaging in Neuro-Oncology: An Update and Overview of a Rapidly Growing Area. Cancers (Basel) 2022; 14:cancers14051103. [PMID: 35267411 PMCID: PMC8909369 DOI: 10.3390/cancers14051103] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/08/2022] [Accepted: 02/19/2022] [Indexed: 12/21/2022] Open
Abstract
Simple Summary Positron emission tomography (PET) is a functional imaging technique which plays an increasingly important role in the management of brain tumors. Owing different radiotracers, PET allows to image different metabolic aspects of the brain tumors. This review outlines currently available PET radiotracers and their respective indications in neuro-oncology. It specifically focuses on the investigation of gliomas, meningiomas, primary central nervous system lymphomas as well as brain metastases. Recent advances in the production of PET radiotracers, image analyses and translational applications to peptide radionuclide receptor therapy, which allow to treat brain tumors with radiotracers, are also discussed. The objective of this review is to provide a comprehensive overview of PET imaging’s potential in neuro-oncology as an adjunct to brain magnetic resonance imaging (MRI). Abstract PET plays an increasingly important role in the management of brain tumors. This review outlines currently available PET radiotracers and their respective indications. It specifically focuses on 18F-FDG, amino acid and somatostatin receptor radiotracers, for imaging gliomas, meningiomas, primary central nervous system lymphomas as well as brain metastases. Recent advances in radiopharmaceuticals, image analyses and translational applications to therapy are also discussed. The objective of this review is to provide a comprehensive overview of PET imaging’s potential in neuro-oncology as an adjunct to brain MRI for all medical professionals implicated in brain tumor diagnosis and care.
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Zhang SS, Zhu L, Peng Y, Zhang L, Chao FL, Jiang L, Xiao Q, Liang X, Tang J, Yang H, He Q, Guo YJ, Zhou CN, Tang Y. Long-term running exercise improves cognitive function and promotes microglial glucose metabolism and morphological plasticity in the hippocampus of APP/PS1 mice. J Neuroinflammation 2022; 19:34. [PMID: 35123512 PMCID: PMC8817568 DOI: 10.1186/s12974-022-02401-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Accepted: 01/24/2022] [Indexed: 02/06/2023] Open
Abstract
Background The role of physical exercise in the prevention of Alzheimer’s disease (AD) has been widely studied. Microglia play an important role in AD. Triggering receptor expressed in myeloid cells 2 (TREM2) is expressed on microglia and is known to mediate microglial metabolic activity and brain glucose metabolism. However, the relationship between brain glucose metabolism and microglial metabolic activity during running exercise in APP/PS1 mice remains unclear. Methods Ten-month-old male APP/PS1 mice and wild-type mice were randomly divided into sedentary groups or running groups (AD_Sed, WT_Sed, AD_Run and WT_Run, n = 20/group). Running mice had free access to a running wheel for 3 months. Behavioral tests, [18]F-FDG-PET and hippocampal RNA-Seq were performed. The expression levels of microglial glucose transporter (GLUT5), TREM2, soluble TREM2 (sTREM2), TYRO protein tyrosine kinase binding protein (TYROBP), secreted phosphoprotein 1 (SPP1), and phosphorylated spleen tyrosine kinase (p-SYK) were estimated by western blot or ELISA. Immunohistochemistry, stereological methods and immunofluorescence were used to investigate the morphology, proliferation and activity of microglia. Results Long-term voluntary running significantly improved cognitive function in APP/PS1 mice. Although there were few differentially expressed genes (DEGs), gene set enrichment analysis (GSEA) showed enriched glycometabolic pathways in APP/PS1 running mice. Running exercise increased FDG uptake in the hippocampus of APP/PS1 mice, as well as the protein expression of GLUT5, TREM2, SPP1 and p-SYK. The level of sTREM2 decreased in the plasma of APP/PS1 running mice. The number of microglia, the length and endpoints of microglial processes, and the ratio of GLUT5+/IBA1+ microglia were increased in the dentate gyrus (DG) of APP/PS1 running mice. Running exercise did not alter the number of 5-bromo-2′-deoxyuridine (BrdU)+/IBA1+ microglia but reduced the immunoactivity of CD68 in the hippocampus of APP/PS1 mice. Conclusions Running exercise inhibited TREM2 shedding and maintained TREM2 protein levels, which were accompanied by the promotion of brain glucose metabolism, microglial glucose metabolism and morphological plasticity in the hippocampus of AD mice. Microglia might be a structural target responsible for the benefits of running exercise in AD. Promoting microglial glucose metabolism and morphological plasticity modulated by TREM2 might be a novel strategy for AD treatment. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02401-5.
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Mahaman YAR, Embaye KS, Huang F, Li L, Zhu F, Wang JZ, Liu R, Feng J, Wang X. Biomarkers used in Alzheimer's disease diagnosis, treatment, and prevention. Ageing Res Rev 2022; 74:101544. [PMID: 34933129 DOI: 10.1016/j.arr.2021.101544] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 12/09/2021] [Accepted: 12/15/2021] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD), being the number one in terms of dementia burden, is an insidious age-related neurodegenerative disease and is presently considered a global public health threat. Its main histological hallmarks are the Aβ senile plaques and the P-tau neurofibrillary tangles, while clinically it is marked by a progressive cognitive decline that reflects the underlying synaptic loss and neurodegeneration. Many of the drug therapies targeting the two pathological hallmarks namely Aβ and P-tau have been proven futile. This is probably attributed to the initiation of therapy at a stage where cognitive alterations are already obvious. In other words, the underlying neuropathological changes are at a stage where these drugs lack any therapeutic value in reversing the damage. Therefore, there is an urgent need to start treatment in the very early stage where these changes can be reversed, and hence, early diagnosis is of primordial importance. To this aim, the use of robust and informative biomarkers that could provide accurate diagnosis preferably at an earlier phase of the disease is of the essence. To date, several biomarkers have been established that, to a different extent, allow researchers and clinicians to evaluate, diagnose, and more specially exclude other related pathologies. In this study, we extensively reviewed data on the currently explored biomarkers in terms of AD pathology-specific and non-specific biomarkers and highlighted the recent developments in the diagnostic and theragnostic domains. In the end, we have presented a separate elaboration on aspects of future perspectives and concluding remarks.
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Joo YH, Lee MW, Son YD, Chang KA, Yaqub M, Kim HK, Cumming P, Kim JH. In Vivo Cerebral Translocator Protein (TSPO) Binding and Its Relationship with Blood Adiponectin Levels in Treatment-Naïve Young Adults with Major Depression: A [ 11C]PK11195 PET Study. Biomedicines 2021; 10:biomedicines10010034. [PMID: 35052718 PMCID: PMC8773340 DOI: 10.3390/biomedicines10010034] [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: 10/12/2021] [Revised: 12/05/2021] [Accepted: 12/20/2021] [Indexed: 12/15/2022] Open
Abstract
Adiponectin is an adipokine that mediates cellular cholesterol efflux and plays important roles in neuroinflammatory processes. In this study, we undertook positron emission tomography (PET) with the translocator protein (TSPO) ligand [11C]PK11195 and measured serum adiponectin levels in groups of treatment-naïve young adult patients with major depressive disorder (MDD) and matched healthy controls. Thirty treatment-naïve MDD patients (median age: 24 years) and twenty-three healthy controls underwent [11C]PK11195 PET. We quantified TSPO availability in brain as the [11C]PK11195 binding potential (BPND) using a reference tissue model in conjunction with the supervised cluster analysis (SVCA4) algorithm. Age, sex distribution, body mass index, and serum adiponectin levels did not differ between the groups. Between-group analysis using a region-of-interest approach showed significantly higher [11C]PK11195 BPND in the left anterior and right posterior cingulate cortices in MDD patients than in controls. Serum adiponectin levels had significant negative correlations with [11C]PK11195 BPND in the bilateral hippocampus in MDD patients, but significant positive correlations in the bilateral hippocampus in the control group. Our results indicate significantly higher TSPO binding in the anterior and posterior cingulate cortices in treatment-naïve young MDD patients, suggesting microglial activation in these limbic regions, which are involved in cognitive and emotional processing. The opposite correlations between [11C]PK11195 BPND in the hippocampus with serum adiponectin levels in MDD and control groups suggest that microglial activation in the hippocampus may respond differentially to adiponectin signaling in MDD and healthy subjects, possibly with respect to microglial phenotype.
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Affiliation(s)
- Yo-Han Joo
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (M.-W.L.); (Y.-D.S.); (K.-A.C.); (H.-K.K.)
| | - Min-Woo Lee
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (M.-W.L.); (Y.-D.S.); (K.-A.C.); (H.-K.K.)
| | - Young-Don Son
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (M.-W.L.); (Y.-D.S.); (K.-A.C.); (H.-K.K.)
- Department of Biomedical Engineering, College of Health Science, Gachon University, Incheon 21936, Korea
- Gachon Advanced Institute for Health Science and Technology, Graduate School, Gachon University, Incheon 21565, Korea
| | - Keun-A Chang
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (M.-W.L.); (Y.-D.S.); (K.-A.C.); (H.-K.K.)
- Gachon Advanced Institute for Health Science and Technology, Graduate School, Gachon University, Incheon 21565, Korea
- Department of Pharmacology, Gachon University College of Medicine, Gachon University, Incheon 21936, Korea
| | - Maqsood Yaqub
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, 1081 HV Amsterdam, The Netherlands;
| | - Hang-Keun Kim
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (M.-W.L.); (Y.-D.S.); (K.-A.C.); (H.-K.K.)
- Department of Biomedical Engineering, College of Health Science, Gachon University, Incheon 21936, Korea
- Gachon Advanced Institute for Health Science and Technology, Graduate School, Gachon University, Incheon 21565, Korea
| | - Paul Cumming
- Department of Nuclear Medicine, Inselspital, Bern University, CH-3010 Bern, Switzerland;
- School of Psychology and Counselling, Queensland University of Technology, Brisbane 4059, Australia
| | - Jong-Hoon Kim
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (M.-W.L.); (Y.-D.S.); (K.-A.C.); (H.-K.K.)
- Gachon Advanced Institute for Health Science and Technology, Graduate School, Gachon University, Incheon 21565, Korea
- Department of Psychiatry, Gachon University College of Medicine, Gil Medical Center, Gachon University, Incheon 21565, Korea
- Correspondence: ; Tel.: +82-32-460-2696
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Chauveau F, Becker G, Boutin H. Have (R)-[ 11C]PK11195 challengers fulfilled the promise? A scoping review of clinical TSPO PET studies. Eur J Nucl Med Mol Imaging 2021; 49:201-220. [PMID: 34387719 PMCID: PMC8712292 DOI: 10.1007/s00259-021-05425-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 05/19/2021] [Indexed: 12/19/2022]
Abstract
PURPOSE The prototypical TSPO radiotracer (R)-[11C]PK11195 has been used in humans for more than thirty years to visualize neuroinflammation in several pathologies. Alternative radiotracers have been developed to improve signal-to-noise ratio and started to be tested clinically in 2008. Here we examined the scientific value of these "(R)-[11C]PK11195 challengers" in clinical research to determine if they could supersede (R)-[11C]PK11195. METHODS A systematic MEDLINE (PubMed) search was performed (up to end of year 2020) to extract publications reporting TSPO PET in patients with identified pathologies, excluding studies in healthy subjects and methodological studies. RESULTS Of the 288 publications selected, 152 used 13 challengers, and 142 used (R)-[11C]PK11195. Over the last 20 years, the number of (R)-[11C]PK11195 studies remained stable (6 ± 3 per year), but was surpassed by the total number of challenger studies for the last 6 years. In total, 3914 patients underwent a TSPO PET scan, and 47% (1851 patients) received (R)-[11C]PK11195. The 2 main challengers were [11C]PBR28 (24%-938 patients) and [18F]FEPPA (11%-429 patients). Only one-in-ten patients (11%-447) underwent 2 TSPO scans, among whom 40 (1%) were scanned with 2 different TSPO radiotracers. CONCLUSIONS Generally, challengers confirmed disease-specific initial (R)-[11C]PK11195 findings. However, while their better signal-to-noise ratio seems particularly useful in diseases with moderate and widespread neuroinflammation, most challengers present an allelic-dependent (Ala147Thr polymorphism) TSPO binding and genetic stratification is hindering their clinical implementation. As new challengers, insensitive to TSPO human polymorphism, are about to enter clinical evaluation, we propose this systematic review to be regularly updated (living review).
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Affiliation(s)
- Fabien Chauveau
- University of Lyon, Lyon Neuroscience Research Center (CRNL), CNRS UMR5292, INSERM U1028, University Lyon 1, Lyon, France.
| | - Guillaume Becker
- GIGA - CRC In Vivo Imaging, University Liege, Liege, Belgium
- University of Lyon, CarMeN Laboratory, INSERM U1060, University Lyon 1, Hospices Civils Lyon, Lyon, France
| | - Hervé Boutin
- Faculty of Biology Medicine and Health, Wolfson Molecular Imaging Centre, University of Manchester, Manchester, UK.
- Wolfson Molecular Imaging Centre, University of Manchester, Manchester, UK.
- Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance & University of Manchester, Manchester, UK.
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De Picker LJ, Haarman BCM. Applicability, potential and limitations of TSPO PET imaging as a clinical immunopsychiatry biomarker. Eur J Nucl Med Mol Imaging 2021; 49:164-173. [PMID: 33735406 DOI: 10.1007/s00259-021-05308-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/08/2021] [Indexed: 02/08/2023]
Abstract
PURPOSE TSPO PET imaging may hold promise as a single-step diagnostic work-up for clinical immunopsychiatry. This review paper on the clinical applicability of TSPO PET for primary psychiatric disorders discusses if and why TSPO PET imaging might become the first clinical immunopsychiatry biomarker and the investment prerequisites and scientific advancements needed to accommodate this transition from bench to bedside. METHODS We conducted a systematic search of the literature to identify clinical studies of TSPO PET imaging in patients with primary psychiatric disorders. We included both original case-control studies as well as longitudinal cohort studies of patients with a primary psychiatric diagnosis. RESULTS Thirty-one original studies met our inclusion criteria. In the field of immunopsychiatry, TSPO PET has until now mostly been studied in schizophrenia and related psychotic disorders, and to a lesser extent in mood disorders and neurodevelopmental disorders. Quantitative TSPO PET appears most promising as a predictive biomarker for the transdiagnostic identification of subgroups or disease stages that could benefit from immunological treatments, or as a prognostic biomarker forecasting patients' illness course. Current scanning protocols are still too unreliable, impractical and invasive for clinical use in symptomatic psychiatric patients. CONCLUSION TSPO PET imaging in its present form does not yet offer a sufficiently attractive cost-benefit ratio to become a clinical immunopsychiatry biomarker. Its translation to psychiatric clinical practice will depend on the prioritising of longitudinal research and the establishment of a uniform protocol rendering clinically meaningful TSPO uptake quantification at the shortest possible scan duration without arterial cannulation.
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Affiliation(s)
- Livia J De Picker
- University Psychiatric Hospital Campus Duffel, Stationsstraat 22C, 2570, Duffel, Belgium.
- Collaborative Antwerp Psychiatric Research Institute, University of Antwerp, Wilrijkstraat 1, 2650, Edegem, Belgium.
| | - Benno C M Haarman
- Department of Psychiatry, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700RA, Groningen, The Netherlands
- Rob Giel Research Center (RGOc), University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700RA, Groningen, The Netherlands
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Laudicella R, Quartuccio N, Argiroffi G, Alongi P, Baratto L, Califaretti E, Frantellizzi V, De Vincentis G, Del Sole A, Evangelista L, Baldari S, Bisdas S, Ceci F, Iagaru A. Unconventional non-amino acidic PET radiotracers for molecular imaging in gliomas. Eur J Nucl Med Mol Imaging 2021; 48:3925-3939. [PMID: 33851243 DOI: 10.1007/s00259-021-05352-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 04/04/2021] [Indexed: 02/07/2023]
Abstract
PURPOSE The objective of this review was to explore the potential clinical application of unconventional non-amino acid PET radiopharmaceuticals in patients with gliomas. METHODS A comprehensive search strategy was used based on SCOPUS and PubMed databases using the following string: ("perfusion" OR "angiogenesis" OR "hypoxia" OR "neuroinflammation" OR proliferation OR invasiveness) AND ("brain tumor" OR "glioma") AND ("Positron Emission Tomography" OR PET). From all studies published in English, the most relevant articles were selected for this review, evaluating the mostly used PET radiopharmaceuticals in research centers, beyond amino acid radiotracers and 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG), for the assessment of different biological features, such as perfusion, angiogenesis, hypoxia, neuroinflammation, cell proliferation, tumor invasiveness, and other biological characteristics in patients with glioma. RESULTS At present, the use of non-amino acid PET radiopharmaceuticals specifically designed to assess perfusion, angiogenesis, hypoxia, neuroinflammation, cell proliferation, tumor invasiveness, and other biological features in glioma is still limited. CONCLUSION The use of investigational PET radiopharmaceuticals should be further explored considering their promising potential and studies specifically designed to validate these preliminary findings are needed. In the clinical scenario, advancements in the development of new PET radiopharmaceuticals and new imaging technologies (e.g., PET/MR and the application of the artificial intelligence to medical images) might contribute to improve the clinical translation of these novel radiotracers in the assessment of gliomas.
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Affiliation(s)
- R Laudicella
- Department of Biomedical and Dental Sciences and Morpho-Functional Imaging, Nuclear Medicine Unit, University of Messina, Messina, Italy
| | - N Quartuccio
- Nuclear Medicine Unit, A.R.N.A.S. Ospedali Civico, Di Cristina e Benfratelli, Palermo, Italy
| | - G Argiroffi
- Department of Health Sciences, University of Milan, Milan, Italy
| | - P Alongi
- Nuclear Medicine Unit,, Fondazione Istituto G. Giglio, Ct. da Pietra Pollastra-pisciotto, Cefalù, Italy
| | - L Baratto
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA, USA
| | - E Califaretti
- Division of Nuclear Medicine, Department of Medical Sciences, University of Turin, Corso AM Dogliotti 14, 10126, Turin, Italy
| | - V Frantellizzi
- Department of Radiological Sciences, Oncology and Anatomical Pathology, Sapienza, "Sapienza" University of Rome, Rome, Italy
| | - G De Vincentis
- Department of Radiological Sciences, Oncology and Anatomical Pathology, Sapienza, "Sapienza" University of Rome, Rome, Italy
| | - A Del Sole
- Department of Health Sciences, University of Milan, Milan, Italy
| | - L Evangelista
- Nuclear Medicine Unit, Department of Medicine - DIMED, University of Padua, Padua, Italy
| | - S Baldari
- Department of Biomedical and Dental Sciences and Morpho-Functional Imaging, Nuclear Medicine Unit, University of Messina, Messina, Italy
| | - S Bisdas
- Department of Neuroradiology, University College London, London, UK
| | - Francesco Ceci
- Division of Nuclear Medicine, IEO European Institute of Oncology, IRCCS, Milan, Italy.
| | - Andrei Iagaru
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA, USA
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Lim TX, Ahamed M, Reutens DC. The aryl hydrocarbon receptor: A diagnostic and therapeutic target in glioma. Drug Discov Today 2021; 27:422-435. [PMID: 34624509 DOI: 10.1016/j.drudis.2021.09.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 07/29/2021] [Accepted: 09/29/2021] [Indexed: 12/19/2022]
Abstract
Glioblastoma multiforme (GBM) is a deadly disease; 5-year survival rates have shown little improvement over the past 30 years. In vivo positron emission tomography (PET) imaging is an important method of identifying potential diagnostic and therapeutic molecular targets non-invasively. The aryl hydrocarbon receptor (AhR) is a transcription factor that regulates multiple genes involved in immune response modulation and tumorigenesis. The AhR is an attractive potential drug target and studies have shown that its activation by small molecules can modulate innate and adaptive immunity beneficially and prevent AhR-mediated tumour promotion in several cancer types. In this review, we provide an overview of the role of the AhR in glioma tumorigenesis and highlight its potential as an emerging biomarker for glioma therapies targeting the tumour immune response and PET diagnostics.
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Affiliation(s)
- Ting Xiang Lim
- ARC Centre for Innovation in Biomedical Imaging Technology, Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD, Australia
| | - Muneer Ahamed
- ARC Centre for Innovation in Biomedical Imaging Technology, Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD, Australia
| | - David C Reutens
- ARC Centre for Innovation in Biomedical Imaging Technology, Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD, Australia.
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Abstract
The use of PET imaging agents in oncology, cardiovascular disease, and neurodegenerative disease shows the power of this technique in evaluating the molecular and biological characteristics of numerous diseases. These agents provide crucial information for designing therapeutic strategies for individual patients. Novel PET tracers are in continual development and many have potential use in clinical and research settings. This article discusses the potential applications of tracers in diagnostics, the biological characteristics of diseases, the ability to provide prognostic indicators, and using this information to guide treatment strategies including monitoring treatment efficacy in real time to improve outcomes and survival.
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32
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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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Scott MC, Bedi SS, Olson SD, Sears CM, Cox CS. Microglia as therapeutic targets after neurological injury: strategy for cell therapy. Expert Opin Ther Targets 2021; 25:365-380. [PMID: 34029505 DOI: 10.1080/14728222.2021.1934447] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Microglia is the resident tissue macrophages of the central nervous system. Prolonged microglial activation often occurs after traumatic brain injury and is associated with deteriorating neurocognitive outcomes. Resolution of microglial activation is associated with limited tissue loss and improved neurocognitive outcomes. Limiting the prolonged pro-inflammatory response and the associated secondary tissue injury provides the rationale and scientific premise for considering microglia as a therapeutic target. AREAS COVERED In this review, we discuss markers of microglial activation, such as immunophenotype and microglial response to injury, including cytokine/chemokine release, free radical formation, morphology, phagocytosis, and metabolic shifts. We compare the origin and role in neuroinflammation of microglia and monocytes/macrophages. We review potential therapeutic targets to shift microglial polarization. Finally, we review the effect of cell therapy on microglia. EXPERT OPINION Dysregulated microglial activation after neurologic injury, such as traumatic brain injury, can worsen tissue damage and functional outcomes. There are potential targets in microglia to attenuate this activation, such as proteins and molecules that regulate microglia polarization. Cellular therapeutics that limit, but do not eliminate, the inflammatory response have improved outcomes in animal models by reducing pro-inflammatory microglial activation via secondary signaling. These findings have been replicated in early phase clinical trials.
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Affiliation(s)
- M Collins Scott
- Department of Pediatric Surgery, University of Texas Health Science Center at Houston (Uthealth), USA
| | - Supinder S Bedi
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Houston, Texas, USA
| | - Scott D Olson
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Houston, Texas, USA
| | - Candice M Sears
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Houston, Texas, USA
| | - Charles S Cox
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Houston, Texas, USA
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Aertker BM, Kumar A, Cardenas F, Gudenkauf F, Sequeira D, Prossin AR, Srivastava AK, Cox CS, Bedi SS. PET Imaging of Peripheral Benzodiazepine Receptor Standard Uptake Value Increases After Controlled Cortical Impact, a Rodent Model of Traumatic Brain Injury. ASN Neuro 2021; 13:17590914211014135. [PMID: 33957800 PMCID: PMC8172335 DOI: 10.1177/17590914211014135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Traumatic brain injury (TBI) is a chronic, life threatening injury for which few
effective interventions are available. Evidence in animal models suggests
un-checked immune activation may contribute to the pathophysiology. Changes in
regional density of active brain microglia can be quantified in vivo with
positron emission topography (PET) with the relatively selective radiotracer,
peripheral benzodiazepine receptor 28 (11 C-PBR28). Phenotypic assessment
(activated vs resting) can subsequently be assessed (ex vivo) using
morphological techniques. To elucidate the mechanistic contribution of immune
cells in due to TBI, we employed a hybrid approach involving both in vivo
(11 C-PBR28 PET) and ex vivo (morphology) to elucidate the role of immune cells
in a controlled cortical impact (CCI), a rodent model for TBI. Density of
activated brain microglia/macrophages was quantified 120 hours after injury
using the standardized uptake value (SUV) approach. Ex vivo morphological
analysis from specific brain regions using IBA-1 antibodies differentiated
ramified (resting) from amoeboid (activated) immune cells. Additional
immunostaining of PBRs facilitated co-localization of PBRs with IBA-1 staining
to further validate PET data. Injured animals displayed greater PBR28suv when
compared to sham animals. Immunohistochemistry demonstrated elevated density of
amoeboid microglia/macrophages in the ipsilateral dentate gyrus, corpus
callosum, thalami and injury penumbra of injured animals compared to sham
animals. PBR co-stained with amoeboid microglia/macrophages in the injury
penumbra and not with astrocytes. These data suggest the technologies evaluated
may serve as bio-signatures of neuroinflammation following severe brain injury
in small animals, potentially enabling in vivo tracking of neuroinflammation
following TBI and cellular-based therapies.
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Affiliation(s)
- Benjamin M Aertker
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Texas, United States
| | - Akshita Kumar
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Texas, United States
| | - Fanni Cardenas
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Texas, United States
| | - Franciska Gudenkauf
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Texas, United States
| | - David Sequeira
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Texas, United States
| | - Alan R Prossin
- Department of Psychiatry and Behavioral Sciences, University of Texas Medical School at Houston, Texas, United States
| | - Amit K Srivastava
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Texas, United States
| | - Charles S Cox
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Texas, United States
| | - Supinder S Bedi
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Texas, United States
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35
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Jewells VL, Yuan H, Merrill JR, Frank JE, Patel A, Cohen SM, Giglio B, Feinberg NN, Matsushima GK, Li Z. Assessment of 18F-PBR-111 in the Cuprizone Mouse Model of Multiple Sclerosis. Diagnostics (Basel) 2021; 11:diagnostics11050786. [PMID: 33925560 PMCID: PMC8145256 DOI: 10.3390/diagnostics11050786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/20/2021] [Accepted: 04/22/2021] [Indexed: 12/28/2022] Open
Abstract
The study aims to assess site assessment of the performance of 18F-PBR-111 as a neuroinflammation marker in the cuprizone mouse model of multiple sclerosis (MS). 18F-PBR-111 PET imaging has not been well evaluated in multiple sclerosis applications both in preclinical and clinical research. This study will help establish the potential utility of 18F-PBR-111 PET in preclinical MS research and future animal and future human applications. 18F-PBR-111 PET/CT was conducted at 3.5 weeks (n = 7) and 5.0 weeks (n = 7) after cuprizone treatment or sham control (n = 3) in the mouse model. A subgroup of mice underwent autoradiography with cryosectioned brain tissue. T2 weighted MRI was performed to obtain the brain structural data of each mouse. 18F-PBR-111 uptake was assessed in multiple brain regions with PET and autoradiography images. The correlation between autoradiography and immunofluorescence staining of neuroinflammation (F4/80 and CD11b) was measured. Compared to control mice, significant 18F-PBR-111 uptake in the corpus callosum (p < 0.001), striatum (caudate and internal capsule, p < 0.001), and hippocampus (p < 0.05) was identified with PET images at both 3.5 weeks and 5.0 weeks, and validated with autoradiography. No significant uptake differences were detected between 3.5 weeks and 5.0 weeks assessing these regions as a whole, although there was a trend of increased uptake at 5.0 weeks compared to 3.5 weeks in the CC. High 18F-PBR-111 uptake regions correlated with microglial/macrophage locations by immunofluorescence staining with F4/80 and CD11b antibodies. 18F-PBR-111 uptake in anatomic locations correlated with activated microglia at histology in the cuprizone mouse model of MS suggests that 18F-PBR-111 has potential for in vivo evaluation of therapy response and potential for use in MS patients and animal studies.
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Affiliation(s)
- Valerie L. Jewells
- Department of Radiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (H.Y.); (Z.L.)
- Correspondence: ; Fax: +1-(919)-966-1994
| | - Hong Yuan
- Department of Radiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (H.Y.); (Z.L.)
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (J.R.M.); (J.E.F.); (B.G.)
| | - Joseph R. Merrill
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (J.R.M.); (J.E.F.); (B.G.)
| | - Jonathan E. Frank
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (J.R.M.); (J.E.F.); (B.G.)
| | - Akhil Patel
- UNC Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (A.P.); (G.K.M.)
| | - Stephanie M. Cohen
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (S.M.C.); (N.N.F.)
| | - Ben Giglio
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (J.R.M.); (J.E.F.); (B.G.)
| | - Nana Nikolaishvili Feinberg
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (S.M.C.); (N.N.F.)
| | - Glenn K. Matsushima
- UNC Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (A.P.); (G.K.M.)
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Integrative Program Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Zibo Li
- Department of Radiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (H.Y.); (Z.L.)
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (J.R.M.); (J.E.F.); (B.G.)
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Imaging Inflammation with Positron Emission Tomography. Biomedicines 2021; 9:biomedicines9020212. [PMID: 33669804 PMCID: PMC7922638 DOI: 10.3390/biomedicines9020212] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 01/28/2021] [Accepted: 02/12/2021] [Indexed: 12/19/2022] Open
Abstract
The impact of inflammation on the outcome of many medical conditions such as cardiovascular diseases, neurological disorders, infections, cancer, and autoimmune diseases has been widely acknowledged. However, in contrast to neurological, oncologic, and cardiovascular disorders, imaging plays a minor role in research and management of inflammation. Imaging can provide insights into individual and temporospatial biology and grade of inflammation which can be of diagnostic, therapeutic, and prognostic value. There is therefore an urgent need to evaluate and understand current approaches and potential applications for imaging of inflammation. This review discusses radiotracers for positron emission tomography (PET) that have been used to image inflammation in cardiovascular diseases and other inflammatory conditions with a special emphasis on radiotracers that have already been successfully applied in clinical settings.
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Zhang L, Hu K, Shao T, Hou L, Zhang S, Ye W, Josephson L, Meyer JH, Zhang MR, Vasdev N, Wang J, Xu H, Wang L, Liang SH. Recent developments on PET radiotracers for TSPO and their applications in neuroimaging. Acta Pharm Sin B 2021; 11:373-393. [PMID: 33643818 PMCID: PMC7893127 DOI: 10.1016/j.apsb.2020.08.006] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 07/15/2020] [Accepted: 07/29/2020] [Indexed: 12/12/2022] Open
Abstract
The 18 kDa translocator protein (TSPO), previously known as the peripheral benzodiazepine receptor, is predominately localized to the outer mitochondrial membrane in steroidogenic cells. Brain TSPO expression is relatively low under physiological conditions, but is upregulated in response to glial cell activation. As the primary index of neuroinflammation, TSPO is implicated in the pathogenesis and progression of numerous neuropsychiatric disorders and neurodegenerative diseases, including Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), multiple sclerosis (MS), major depressive disorder (MDD) and obsessive compulsive disorder (OCD). In this context, numerous TSPO-targeted positron emission tomography (PET) tracers have been developed. Among them, several radioligands have advanced to clinical research studies. In this review, we will overview the recent development of TSPO PET tracers, focusing on the radioligand design, radioisotope labeling, pharmacokinetics, and PET imaging evaluation. Additionally, we will consider current limitations, as well as translational potential for future application of TSPO radiopharmaceuticals. This review aims to not only present the challenges in current TSPO PET imaging, but to also provide a new perspective on TSPO targeted PET tracer discovery efforts. Addressing these challenges will facilitate the translation of TSPO in clinical studies of neuroinflammation associated with central nervous system diseases.
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Key Words
- AD, Alzheimer's disease
- ALS, amyotrophic lateral sclerosis
- AMPA, α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid
- ANT, adenine nucleotide transporter
- Am, molar activities
- BBB, blood‒brain barrier
- BMSC, bone marrow stromal cells
- BP, binding potential
- BPND, non-displaceable binding potential
- BcTSPO, Bacillus cereus TSPO
- CBD, corticobasal degeneration
- CNS disorders
- CNS, central nervous system
- CRAC, cholesterol recognition amino acid consensus sequence
- DLB, Lewy body dementias
- EP, epilepsy
- FTD, frontotemporal dementia
- HAB, high-affinity binding
- HD, Huntington's disease
- HSE, herpes simplex encephalitis
- IMM, inner mitochondrial membrane
- KA, kainic acid
- LAB, low-affinity binding
- LPS, lipopolysaccharide
- MAB, mixed-affinity binding
- MAO-B, monoamine oxidase B
- MCI, mild cognitive impairment
- MDD, major depressive disorder
- MMSE, mini-mental state examination
- MRI, magnetic resonance imaging
- MS, multiple sclerosis
- MSA, multiple system atrophy
- Microglial activation
- NAA/Cr, N-acetylaspartate/creatine
- Neuroinflammation
- OCD, obsessive compulsive disorder
- OMM, outer mitochondrial membrane
- P2X7R, purinergic receptor P2X7
- PAP7, RIa-associated protein
- PBR, peripheral benzodiazepine receptor
- PCA, posterior cortical atrophy
- PD, Parkinson's disease
- PDD, PD dementia
- PET, positron emission tomography
- PKA, protein kinase A
- PRAX-1, PBR-associated protein 1
- PSP, progressive supranuclear palsy
- Positron emission tomography (PET)
- PpIX, protoporphyrin IX
- QA, quinolinic acid
- RCYs, radiochemical yields
- ROS, reactive oxygen species
- RRMS, relapsing remitting multiple sclerosis
- SA, specific activity
- SAH, subarachnoid hemorrhage
- SAR, structure–activity relationship
- SCIDY, spirocyclic iodonium ylide
- SNL, selective neuronal loss
- SNR, signal to noise ratio
- SUV, standard uptake volume
- SUVR, standard uptake volume ratio
- TBAH, tetrabutyl ammonium hydroxide
- TBI, traumatic brain injury
- TLE, temporal lobe epilepsy
- TSPO
- TSPO, translocator protein
- VDAC, voltage-dependent anion channel
- VT, distribution volume
- d.c. RCYs, decay-corrected radiochemical yields
- dMCAO, distal middle cerebral artery occlusion
- fP, plasma free fraction
- n.d.c. RCYs, non-decay-corrected radiochemical yields
- p.i., post-injection
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Mueller C, Lin JC, Sheriff S, Maudsley AA, Younger JW. Evidence of widespread metabolite abnormalities in Myalgic encephalomyelitis/chronic fatigue syndrome: assessment with whole-brain magnetic resonance spectroscopy. Brain Imaging Behav 2021; 14:562-572. [PMID: 30617782 DOI: 10.1007/s11682-018-0029-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Previous neuroimaging studies have detected markers of neuroinflammation in patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Magnetic Resonance Spectroscopy (MRS) is suitable for measuring brain metabolites linked to inflammation, but has only been applied to discrete regions of interest in ME/CFS. We extended the MRS analysis of ME/CFS by capturing multi-voxel information across the entire brain. Additionally, we tested whether MRS-derived brain temperature is elevated in ME/CFS patients. Fifteen women with ME/CFS and 15 age- and gender-matched healthy controls completed fatigue and mood symptom questionnaires and whole-brain echo-planar spectroscopic imaging (EPSI). Choline (CHO), myo-inositol (MI), lactate (LAC), and N-acetylaspartate (NAA) were quantified in 47 regions, expressed as ratios over creatine (CR), and compared between ME/CFS patients and controls using independent-samples t-tests. Brain temperature was similarly tested between groups. Significant between-group differences were detected in several regions, most notably elevated CHO/CR in the left anterior cingulate (p < 0.001). Metabolite ratios in seven regions were correlated with fatigue (p < 0.05). ME/CFS patients had increased temperature in the right insula, putamen, frontal cortex, thalamus, and the cerebellum (all p < 0.05), which was not attributable to increased body temperature or differences in cerebral perfusion. Brain temperature increases converged with elevated LAC/CR in the right insula, right thalamus, and cerebellum (all p < 0.05). We report metabolite and temperature abnormalities in ME/CFS patients in widely distributed regions. Our findings may indicate that ME/CFS involves neuroinflammation.
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Affiliation(s)
- Christina Mueller
- Department of Psychology, The University of Alabama at Birmingham, 1720 2nd Ave S, Birmingham, AL, 35294, USA
| | - Joanne C Lin
- Department of Psychology, The University of Alabama at Birmingham, 1720 2nd Ave S, Birmingham, AL, 35294, USA
| | - Sulaiman Sheriff
- Department of Radiology, Miller School of Medicine, University of Miami, 1600 NW 10th Ave #1140, Miami, FL, 33136, USA
| | - Andrew A Maudsley
- Department of Radiology, Miller School of Medicine, University of Miami, 1600 NW 10th Ave #1140, Miami, FL, 33136, USA
| | - Jarred W Younger
- Department of Psychology, The University of Alabama at Birmingham, 1720 2nd Ave S, Birmingham, AL, 35294, USA.
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Foray C, Valtorta S, Barca C, Winkeler A, Roll W, Müther M, Wagner S, Gardner ML, Hermann S, Schäfers M, Grauer OM, Moresco RM, Zinnhardt B, Jacobs AH. Imaging temozolomide-induced changes in the myeloid glioma microenvironment. Theranostics 2021; 11:2020-2033. [PMID: 33500706 PMCID: PMC7797694 DOI: 10.7150/thno.47269] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 09/21/2020] [Indexed: 12/26/2022] Open
Abstract
Rationale: The heterogeneous nature of gliomas makes the development and application of novel treatments challenging. In particular, infiltrating myeloid cells play a role in tumor progression and therapy resistance. Hence, a detailed understanding of the dynamic interplay of tumor cells and immune cells in vivo is necessary. To investigate the complex interaction between tumor progression and therapy-induced changes in the myeloid immune component of the tumor microenvironment, we used a combination of [18F]FET (amino acid metabolism) and [18F]DPA-714 (TSPO, GAMMs, tumor cells, astrocytes, endothelial cells) PET/MRI together with immune-phenotyping. The aim of the study was to monitor temozolomide (TMZ) treatment response and therapy-induced changes in the inflammatory tumor microenvironment (TME). Methods: Eighteen NMRInu/nu mice orthotopically implanted with Gli36dEGFR cells underwent MRI and PET/CT scans before and after treatment with TMZ or DMSO (vehicle). Tumor-to-background (striatum) uptake ratios were calculated and areas of unique tracer uptake (FET vs. DPA) were determined using an atlas-based volumetric approach. Results: TMZ therapy significantly modified the spatial distribution and uptake of both tracers. [18F]FET uptake was significantly reduced after therapy (-53 ± 84%) accompanied by a significant decrease of tumor volume (-17 ± 6%). In contrast, a significant increase (61 ± 33%) of [18F]DPA-714 uptake was detected by TSPO imaging in specific areas of the tumor. Immunohistochemistry (IHC) validated the reduction in tumor volumes and further revealed the presence of reactive TSPO-expressing glioma-associated microglia/macrophages (GAMMs) in the TME. Conclusion: We confirm the efficiency of [18F]FET-PET for monitoring TMZ-treatment response and demonstrate that in vivo TSPO-PET performed with [18F]DPA-714 can be used to identify specific reactive areas of myeloid cell infiltration in the TME.
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Cui Y, Pan M, Ma J, Song X, Cao W, Zhang P. Recent progress in the use of mitochondrial membrane permeability transition pore in mitochondrial dysfunction-related disease therapies. Mol Cell Biochem 2021; 476:493-506. [PMID: 33000352 DOI: 10.1007/s11010-020-03926-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 09/23/2020] [Indexed: 12/13/2022]
Abstract
Mitochondria have various cellular functions, including ATP synthesis, calcium homeostasis, cell senescence, and death. Mitochondrial dysfunction has been identified in a variety of disorders correlated with human health. Among the many underlying mechanisms of mitochondrial dysfunction, the opening up of the mitochondrial permeability transition pore (mPTP) is one that has drawn increasing interest in recent years. It plays an important role in apoptosis and necrosis; however, the molecular structure and function of the mPTP have still not been fully elucidated. In recent years, the abnormal opening up of the mPTP has been implicated in the development and pathogenesis of diverse diseases including ischemia/reperfusion injury (IRI), neurodegenerative disorders, tumors, and chronic obstructive pulmonary disease (COPD). This review provides a systematic introduction to the possible molecular makeup of the mPTP and summarizes the mitochondrial dysfunction-correlated diseases and highlights possible underlying mechanisms. Since the mPTP is an important target in mitochondrial dysfunction, this review also summarizes potential treatments, which may be used to inhibit pore opening up via the molecules composing mPTP complexes, thus suppressing the progression of mitochondrial dysfunction-related diseases.
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Affiliation(s)
- Yuting Cui
- School of Life Science, Shandong University of Technology, Zibo, Shandong Province, China
| | - Mingyue Pan
- Department of Pharmacy, Shenzhen Luohu People's Hospital, Shenzhen, Guangdong Province, China
| | - Jing Ma
- The Eighth Affiliated Hospital, Sun Yat-Sen University, Shenzhen, Guangdong Province, China
| | - Xinhua Song
- School of Life Science, Shandong University of Technology, Zibo, Shandong Province, China
| | - Weiling Cao
- Department of Pharmacy, Shenzhen Luohu People's Hospital, Shenzhen, Guangdong Province, China.
| | - Peng Zhang
- Department of Pharmacy, Shenzhen Luohu People's Hospital, Shenzhen, Guangdong Province, China.
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Filling the gaps on stroke research: Focus on inflammation and immunity. Brain Behav Immun 2021; 91:649-667. [PMID: 33017613 PMCID: PMC7531595 DOI: 10.1016/j.bbi.2020.09.025] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/10/2020] [Accepted: 09/23/2020] [Indexed: 02/08/2023] Open
Abstract
For the last two decades, researchers have placed hopes in a new era in which a combination of reperfusion and neuroprotection would revolutionize the treatment of stroke. Nevertheless, despite the thousands of papers available in the literature showing positive results in preclinical stroke models, randomized clinical trials have failed to show efficacy. It seems clear now that the existing data obtained in preclinical research have depicted an incomplete picture of stroke pathophysiology. In order to ameliorate bench-to-bed translation, in this review we first describe the main actors on stroke inflammatory and immune responses based on the available preclinical data, highlighting the fact that the link between leukocyte infiltration, lesion volume and neurological outcome remains unclear. We then describe what is known on neuroinflammation and immune responses in stroke patients, and summarize the results of the clinical trials on immunomodulatory drugs. In order to understand the gap between clinical trials and preclinical results on stroke, we discuss in detail the experimental results that served as the basis for the summarized clinical trials on immunomodulatory drugs, focusing on (i) experimental stroke models, (ii) the timing and selection of outcome measuring, (iii) alternative entry routes for leukocytes into the ischemic region, and (iv) factors affecting stroke outcome such as gender differences, ageing, comorbidities like hypertension and diabetes, obesity, tobacco, alcohol consumption and previous infections like Covid-19. We can do better for stroke treatment, especially when targeting inflammation following stroke. We need to re-think the design of stroke experimental setups, notably by (i) using clinically relevant models of stroke, (ii) including both radiological and neurological outcomes, (iii) performing long-term follow-up studies, (iv) conducting large-scale preclinical stroke trials, and (v) including stroke comorbidities in preclinical research.
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Lavisse S, Goutal S, Wimberley C, Tonietto M, Bottlaender M, Gervais P, Kuhnast B, Peyronneau MA, Barret O, Lagarde J, Sarazin M, Hantraye P, Thiriez C, Remy P. Increased microglial activation in patients with Parkinson disease using [ 18F]-DPA714 TSPO PET imaging. Parkinsonism Relat Disord 2020; 82:29-36. [PMID: 33242662 DOI: 10.1016/j.parkreldis.2020.11.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 09/18/2020] [Accepted: 11/11/2020] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Increasing evidence suggests that neuroinflammation is active in Parkinson disease (PD) and contributes to neurodegeneration. This process can be studied in vivo with PET and radioligands targeting TSPO, upregulated in activated microglia. Initial PET studies investigating microglial activation in PD with the [11C]-PK11195 have provided inconclusive results. Here we assess the presence and distribution of neuroinflammatory response in PD patients using [18F]-DPA714 and to correlate imaging biomarkers to dopamine transporter imaging and clinical status. METHODS PD patients (n = 24, Hoehn and Yahr I-III) and 28 healthy controls were scanned with [18F]-DPA714 and [11C]-PE2I and analyzed. They were all genotyped for TSPO polymorphism. Regional binding parameters were estimated (reference Logan graphical approach with supervised cluster analysis). Impact of TSPO genotype was analyzed using Wilcoxon signed-rank test. Differences between groups were investigated using a two-way ANOVA and Tukey post hoc tests. RESULTS PD patients showed significantly higher [18F]-DPA714 binding compared to healthy controls bilaterally in the midbrain (p < 0.001), the frontal cortex (p = 0.001), and the putamen contralateral to the more clinically affected hemibody (p = 0.038). Microglial activation in these regions did not correlate with the severity of motor symptoms, disease duration nor putaminal [11C]-PE2I uptake. However, there was a trend toward a correlation between cortical TSPO binding and disease duration (p = 0.015 uncorrected, p = 0.07 after Bonferroni correction). CONCLUSION [18F]-DPA714 binding confirmed that there is a specific topographic pattern of microglial activation in the nigro-striatal pathway and the frontal cortex of PD patients. TRIAL REGISTRATION Trial registration: INFLAPARK, NCT02319382. Registered 18 December 2014- Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02319382.
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Affiliation(s)
- Sonia Lavisse
- Université Paris-Saclay, CEA, CNRS, MIRCen, Laboratoire des Maladies Neurodégénératives, 92265, Fontenay-aux-Roses, France.
| | - Sébastien Goutal
- Université Paris-Saclay, CEA, CNRS, MIRCen, Laboratoire des Maladies Neurodégénératives, 92265, Fontenay-aux-Roses, France.
| | - Catriona Wimberley
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4, Place du Général Leclerc, Orsay, 91401, France.
| | - Mattéo Tonietto
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4, Place du Général Leclerc, Orsay, 91401, France.
| | - Michel Bottlaender
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4, Place du Général Leclerc, Orsay, 91401, France; Université Paris-Saclay, UNIACT, Neurospin, CEA, 91191, Gif-sur-Yvette, France.
| | - Philippe Gervais
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4, Place du Général Leclerc, Orsay, 91401, France.
| | - Bertrand Kuhnast
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4, Place du Général Leclerc, Orsay, 91401, France.
| | - Marie-Anne Peyronneau
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4, Place du Général Leclerc, Orsay, 91401, France.
| | - Olivier Barret
- Université Paris-Saclay, CEA, CNRS, MIRCen, Laboratoire des Maladies Neurodégénératives, 92265, Fontenay-aux-Roses, France.
| | - Julien Lagarde
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4, Place du Général Leclerc, Orsay, 91401, France; Department of Neurology of Memory and Language, GHU Paris Psychiatrie & Neurosciences, Sainte-Anne Hospital, Paris, 75014, France; Université de Paris, F-75006, France.
| | - Marie Sarazin
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Service Hospitalier Frédéric Joliot, 4, Place du Général Leclerc, Orsay, 91401, France; Department of Neurology of Memory and Language, GHU Paris Psychiatrie & Neurosciences, Sainte-Anne Hospital, Paris, 75014, France; Université de Paris, F-75006, France.
| | - Philippe Hantraye
- Université Paris-Saclay, CEA, CNRS, MIRCen, Laboratoire des Maladies Neurodégénératives, 92265, Fontenay-aux-Roses, France.
| | - Claire Thiriez
- Centre Expert Parkinson, Neurologie, CHU Henri Mondor, AP-HP, 51 Avenue du Maréchal de Lattre de Tassigny, Créteil, France.
| | - Philippe Remy
- Université Paris-Saclay, CEA, CNRS, MIRCen, Laboratoire des Maladies Neurodégénératives, 92265, Fontenay-aux-Roses, France; Centre Expert Parkinson, Neurologie, CHU Henri Mondor, AP-HP, 51 Avenue du Maréchal de Lattre de Tassigny, Créteil, France; IMRB, INSERM, Université Paris Est Créteil and NeurATRIS, France.
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Mou T, Tian J, Tian Y, Yun M, Li J, Dong W, Lu X, Zhu Z, Mi H, Zhang X, Li X. Automated synthesis and preliminary evaluation of [ 18F]FDPA for cardiac inflammation imaging in rats after myocardial infarction. Sci Rep 2020; 10:18685. [PMID: 33122775 PMCID: PMC7596090 DOI: 10.1038/s41598-020-75705-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 10/19/2020] [Indexed: 11/26/2022] Open
Abstract
A translocator protein 18 kDa targeted radiotracer, N,N-diethyl-2-(2-(4-[18F]fluorophenyl)-5,7-dimethylpyrazolo[1,5-a] pyrimidin-3-yl) acetamide ([18F]FDPA), was automated synthetized and evaluated for cardiac inflammation imaging. Various reaction conditions for an automated synthesis were systematically optimized. MicroPET/CT imaging were performed on normal rats and rats with myocardial infarction (MI). Normalized SUV ratios of [18F]FDPA to [13N]NH3 (NSRs) in different regions were calculated to normalize the uptake of [18F]FDPA to perfusion. The amount of TBAOMs and the volume/proportion of water were crucial for synthesis. After optimization, the total synthesis time was 68 min. The non-decay corrected radiochemical yields (RCYs) and molar activities were 19.9 ± 1.7% and 169.7 ± 46.5 GBq/μmol, respectively. In normal rats, [18F]FDPA showed a high and stable cardiac uptake and fast clearance from other organs. In MI rats, NSRs in the peri-infarct and infarct regions, which were infiltrated with massive inflammatory cells revealed by pathology, were higher than that in the remote region (1.20 ± 0.01 and 1.08 ± 0.10 vs. 0.89 ± 0.05, respectively). [18F]FDPA was automated synthesized with high RCYs and molar activities. It showed a high uptake in inflammation regions and offered a wide time window for cardiac imaging, indicating it could be a potential cardiac inflammation imaging agent.
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Affiliation(s)
- Tiantian Mou
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Jing Tian
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Yi Tian
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Mingkai Yun
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Junqi Li
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Wei Dong
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Xia Lu
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Ziwei Zhu
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Hongzhi Mi
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Xiaoli Zhang
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China.
| | - Xiang Li
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China.,Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
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Lebrun B, Barbot M, Tonon MC, Prévot V, Leprince J, Troadec JD. Glial endozepines and energy balance: Old peptides with new tricks. Glia 2020; 69:1079-1093. [PMID: 33105065 DOI: 10.1002/glia.23927] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/09/2020] [Accepted: 10/09/2020] [Indexed: 12/12/2022]
Abstract
The contribution of neuroglial interactions to the regulation of energy balance has gained increasing acceptance in recent years. In this context, endozepines, endogenous analogs of benzodiazepine derived from diazepam-binding inhibitor, are now emerging as major players. Produced by glial cells (astrocytes and tanycytes), endozepines have been known for two decades to exert potent anorexigenic effects by acting at the hypothalamic level. However, it is only recently that their modes of action, including the mechanisms by which they modulate energy metabolism, have begun to be elucidated. The data available today are abundant, significant, and sometimes contradictory, revealing a much more complex regulation than initially expected. Several mechanisms of action of endozepines seem to coexist at the central level, particularly in the hypothalamus. The brainstem has also recently emerged as a potential site of action for endozepines. In addition to their central anorexigenic effects, endozepines may also display peripheral effects promoting orexigenic actions, adding to their complexity and raising yet more questions. In this review, we attempt to provide an overview of our current knowledge in this rapidly evolving field and to pinpoint questions that remain unanswered.
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Affiliation(s)
- Bruno Lebrun
- CNRS 7291, Laboratoire de Neurosciences Cognitives, Aix Marseille University, Marseille, France
| | - Manon Barbot
- CNRS 7291, Laboratoire de Neurosciences Cognitives, Aix Marseille University, Marseille, France
| | - Marie-Christine Tonon
- INSERM U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Normandie Université, Rouen, France
| | - Vincent Prévot
- University of Lille, INSERM, CHU Lille, Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience and Cognition, UMR-S 1172, European Genomic Institute of Diabetes (EGID), Lille, France
| | - Jérôme Leprince
- INSERM U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Normandie Université, Rouen, France
| | - Jean-Denis Troadec
- CNRS 7291, Laboratoire de Neurosciences Cognitives, Aix Marseille University, Marseille, France
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Attwells S, Setiawan E, Rusjan PM, Xu C, Hutton C, Rafiei D, Varughese B, Kahn A, Kish SJ, Vasdev N, Houle S, Meyer JH. Translocator Protein Distribution Volume Predicts Reduction of Symptoms During Open-Label Trial of Celecoxib in Major Depressive Disorder. Biol Psychiatry 2020; 88:649-656. [PMID: 32402468 DOI: 10.1016/j.biopsych.2020.03.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 03/05/2020] [Accepted: 03/11/2020] [Indexed: 01/06/2023]
Abstract
BACKGROUND Gliosis is common among neuropsychiatric diseases, but the relationship between gliosis and response to therapeutics targeting effects of gliosis is largely unknown. Translocator protein total distribution volume (TSPO VT), measured with positron emission tomography, mainly reflects gliosis in neuropsychiatric disease. Here, the primary objective was to determine whether TSPO VT in the prefrontal cortex (PFC) and anterior cingulate cortex (ACC) predicts reduction of depressive symptoms following open-label celecoxib administration in treatment-resistant major depressive disorder. METHODS A total of 41 subjects with treatment-resistant major depressive disorder underwent one [18F]FEPPA positron emission tomography scan to measure PFC and ACC TSPO VT. Open-label oral celecoxib (200 mg, twice daily) was administered for 8 weeks. Change in symptoms was measured with the 17-item Hamilton Depression Rating Scale (HDRS). RESULTS Cumulative mean change in HDRS scores between 0 and 8 weeks of treatment was plotted against PFC and ACC TSPO VT, showing a significant nonlinear relationship. At low TSPO VT values, there was no reduction in HDRS scores, but as TSPO VT values increased, there was a reduction in HDRS scores that then plateaued. This was modeled with a 4-parameter sigmoidal model in which PFC and ACC TSPO VT accounted for 84% and 92% of the variance, respectively. CONCLUSIONS Celecoxib administration in the presence of gliosis labeled by TSPO VT is associated with greater reduction of symptoms. Given the predictiveness of TSPO VT on symptom reduction, this personalized medicine approach of matching a marker of gliosis to medication targeting effects of gliosis should be applied in early development of novel therapeutics, in particular for treatment-resistant major depressive disorder.
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Affiliation(s)
- Sophia Attwells
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Elaine Setiawan
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Pablo M Rusjan
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Cynthia Xu
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Celeste Hutton
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Dorsa Rafiei
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Benjamin Varughese
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Alan Kahn
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Stephen J Kish
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Neil Vasdev
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Sylvain Houle
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Jeffrey H Meyer
- Brain Health Imaging Centre and Campbell Family Mental Health Research Institute, the Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.
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An update into the medicinal chemistry of translocator protein (TSPO) ligands. Eur J Med Chem 2020; 209:112924. [PMID: 33081988 DOI: 10.1016/j.ejmech.2020.112924] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 10/06/2020] [Accepted: 10/06/2020] [Indexed: 01/16/2023]
Abstract
The Translocator Protein 18 kDa (TSPO) has been discovered in 1977 as an alternative binding site for the benzodiazepine diazepam. It is an evolutionary well-conserved and tryptophan-rich 169-amino acids protein with five alpha helical transmembrane domains stretching the outer mitochondrial membrane, with the carboxyl-terminus in the cytosol and a short amino-terminus in the intermembrane space of mitochondrion. At this level, together with the voltage-dependent anion channel (VDAC) and the adenine nucleotide translocase (ANT), it forms the mitochondrial permeability transition pore (MPTP). TSPO expression is ubiquitary, with higher levels in steroid producing tissues; in the central nervous system, it is mainly expressed in glial cells and in neurons. TSPO is implicated in a variety of fundamental cellular processes including steroidogenesis, heme biosynthesis, mitochondrial respiration, mitochondrial membrane potential, cell proliferation and differentiation, cell life/death balance, oxidative stress. Altered TSPO expression has been found in some pathological conditions. In particular, high TSPO expression levels have been documented in cancer, neuroinflammation, and brain injury. Conversely, low TSPO expression levels have been evidenced in anxiety disorders. Therefore, TSPO is not only an interesting drug target for therapeutic purpose (anticonvulsant, anxiolytic, etc.), but also a valid diagnostic marker of related-diseases detectable by fluorescent or radiolabeled ligands. The aim of this report is to present an update of previous reviews dealing with the medicinal chemistry of TSPO and to highlight the most outstanding advances in the development of TSPO ligands as potential therapeutic or diagnostic tools, especially referring to the last five years.
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Beaino W, Janssen B, Kooijman E, Vos R, Schuit RC, O'Brien-Brown J, Kassiou M, van Het Hof B, Vugts DJ, de Vries HE, Windhorst AD. PET imaging of P2X 7R in the experimental autoimmune encephalomyelitis model of multiple sclerosis using [ 11C]SMW139. J Neuroinflammation 2020; 17:300. [PMID: 33054803 PMCID: PMC7556947 DOI: 10.1186/s12974-020-01962-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 09/23/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Non-invasive imaging of the activation status of microglia and the ability to identify a pro- or anti-inflammatory environment can provide valuable insights not only into pathogenesis of neuro-inflammatory and neurodegenerative diseases but also the monitoring of the efficacy of immunomodulatory therapies. P2X7R is highly expressed on pro-inflammatory microglia and [11C]SMW139, a specific P2X7R tracer for positron emission tomography imaging, showed good pharmacokinetics, stability, and brain permeability in vivo. Our objective was to evaluate the potential of [11C]SMW139 for PET imaging of neuroinflammation in vivo in the experimental autoimmune encephalomyelitis (EAE) model. METHODS We induced EAE in Lewis rats by immunization with MBP 69-88 in complete Freund's adjuvant (CFA). We determined the affinity of [11C]SMW139 to human and rat P2X7R using saturation binding assay. Using this tracer, PET imaging was performed at the peak of disease and in the recovery phase. In vivo blocking experiments were conducted to validate the specific brain uptake of the tracer. Immunohistochemistry staining and autoradiography were performed to evaluate the level of neuroinflammation and validate the specific binding of [11C]SMW139. RESULTS [11C]SMW139 showed good affinity for the rat P2X7R with a Kd of 20.6 ± 1.7 nM. The uptake of [11C]SMW139 was significantly higher in EAE animals at the peak of disease compared to the recovery phase but not in CFA control animals. The amplitude of increase of [11C]SMW139 uptake showed significant positive correlation with clinical scores mainly in the spinal cord (Pearson = 0.75, Spearman = 0.76; p < 0.0001). Treating EAE animals with P2X7R antagonist JNJ-47965567 blocked the uptake of [11C]SMW139 in the spinal cord, cerebellum, and brain stem, demonstrating specific accumulation of the tracer. P-glycoprotein blocking with tariquidar (30 mg/kg) did not affect tracer penetration in the brain showing that [11C]SMW139 is not a Pgp substrate. CONCLUSION Our data shows that [11C]SMW139 is a promising PET tracer for imaging neuroinflammation and evaluating the dynamics of pro-inflammatory microglia in the brain. This can provide crucial insights into the role of microglia in disease progression and enables the development of novel treatment strategies aimed at modulating the immune response in order to promote neuroprotection.
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Affiliation(s)
- Wissam Beaino
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands.
| | - Bieneke Janssen
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands.,Present address: Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Esther Kooijman
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands
| | - Ricardo Vos
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands
| | - Robert C Schuit
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands
| | | | - Michael Kassiou
- School of Chemistry, The University of Sydney, Sydney, NSW, Australia
| | - Bert van Het Hof
- Department of Molecular Cell Biology and Immunology, AUMC MS Center Amsterdam, Amsterdam Neuroscience, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Danielle J Vugts
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands
| | - Helga E de Vries
- Department of Molecular Cell Biology and Immunology, AUMC MS Center Amsterdam, Amsterdam Neuroscience, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Albert D Windhorst
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, location VUmc, Amsterdam, The Netherlands
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Raman F, Grandhi S, Murchison CF, Kennedy RE, Landau S, Roberson ED, McConathy J. Biomarker Localization, Analysis, Visualization, Extraction, and Registration (BLAzER) Methodology for Research and Clinical Brain PET Applications. J Alzheimers Dis 2020; 70:1241-1257. [PMID: 31322571 DOI: 10.3233/jad-190329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Tools for efficient evaluation of amyloid- and tau-PET images are needed in both clinical and research settings. OBJECTIVE This study was designed to validate a semi-automated image analysis methodology, called Biomarker Localization, Analysis, Visualization, Extraction, and Registration (BLAzER). We tested BLAzER using two different segmentation platforms, FreeSurfer (FS) and Neuroreader (NR), for regional brain PET quantification in participants in the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset. METHODS 127 amyloid-PET and 55 tau-PET studies with volumetric MRIs were obtained from ADNI. The BLAzER methodology utilizes segmentation of MR images by FS or NR, then visualizes and quantifies regional brain PET data using FDA-cleared software (MIM), enabling quality control to ensure optimal registration and to detect segmentation errors. RESULTS BLAzER analysis required ∼5 min plus segmentation time. BLAzER using FS segmentation showed strong agreement with ADNI for global amyloid-PET standardized uptake value ratios (SUVRs) (r = 0.9922, p < 0.001) and regional tau-PET SUVRs across all Braak staging regions (r > 0.97, p < 0.001) with high inter-operator reproducibility (ICC > 0.97) and nearly identical dichotomization as amyloid-positive or -negative (2 discrepant cases out of 127). Comparing FS versus NR segmentation with BLAzER, global SUVRs were strongly correlated for amyloid-PET (r = 0.9841, p < 0.001), but were systematically higher (4% on average) with NR, likely due to more inclusion of white matter with NR-defined regions. CONCLUSIONS BLAzER provides an efficient methodology for regional brain PET quantification. FDA-cleared components and visualization of registration reduce barriers between research and clinical applications.
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Affiliation(s)
- Fabio Raman
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA.,Alzheimer's Disease Center, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.,Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Sameera Grandhi
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA.,Alzheimer's Disease Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Charles F Murchison
- Alzheimer's Disease Center, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Biostatistics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Richard E Kennedy
- Alzheimer's Disease Center, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Biostatistics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Susan Landau
- Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA, USA
| | - Erik D Roberson
- Alzheimer's Disease Center, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.,Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jonathan McConathy
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA.,Alzheimer's Disease Center, University of Alabama at Birmingham, Birmingham, AL, USA
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Harms AS, Kordower JH, Sette A, Lindestam Arlehamn CS, Sulzer D, Mach RH. Inflammation in Experimental Models of α-Synucleinopathies. Mov Disord 2020; 36:37-49. [PMID: 33009855 DOI: 10.1002/mds.28264] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/29/2020] [Accepted: 06/17/2020] [Indexed: 12/11/2022] Open
Abstract
Neuroinflammation has long been associated with central nervous system pathology in α-synucleinopathy disorders including Parkinson's disease and multiple system atrophy. In the past decade, research-focused efforts in preclinical and experimental models have rallied around this idea, and considerable effort has been made to delineate critical neuroinflammatory processes. In this article, we discuss challenges in preclinical research, notably the use of animal models to recapitulate and dissect disease phenotypes as well as the need for more sensitive, reliable radiotracers to detect on-target efficacy of immunomodulatory treatments in both human Parkinson's disease as well as preclinical models. © 2020 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Ashley S Harms
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jeffrey H Kordower
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois, USA
| | - Alessandro Sette
- Division of Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, California, USA.,Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | | | - David Sulzer
- Department of Neurology, Columbia University Medical Center, New York, New York, USA.,Department of Psychiatry, Columbia University Medical Center, New York, New York, USA.,Department of Pharmacology, Columbia University Medical Center, New York, New York, USA
| | - Robert H Mach
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Hobson BA, Rowland DJ, Sisó S, Guignet MA, Harmany ZT, Bandara SB, Saito N, Harvey DJ, Bruun DA, Garbow JR, Chaudhari AJ, Lein PJ. TSPO PET Using [18F]PBR111 Reveals Persistent Neuroinflammation Following Acute Diisopropylfluorophosphate Intoxication in the Rat. Toxicol Sci 2020; 170:330-344. [PMID: 31087103 DOI: 10.1093/toxsci/kfz096] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Acute intoxication with organophosphates (OPs) can trigger status epilepticus followed by persistent cognitive impairment and/or electroencephalographic abnormalities. Neuroinflammation is widely posited to influence these persistent neurological consequences. However, testing this hypothesis has been challenging, in part because traditional biometrics preclude longitudinal measures of neuroinflammation within the same animal. Therefore, we evaluated the performance of noninvasive positron emission tomography (PET), using the translocator protein (TSPO) radioligand [18F]PBR111 against classic histopathologic measures of neuroinflammation in a preclinical model of acute intoxication with the OP diisopropylfluorophosphate (DFP). Adult male Sprague Dawley rats administered pyridostigmine bromide (0.1 mg/kg, im) 30 min prior to administration of DFP (4 mg/kg, sc), atropine sulfate (2 mg/kg, im) and 2-pralidoxime (25 mg/kg, im) exhibited moderate-to-severe seizure behavior. TSPO PET performed prior to DFP exposure and at 3, 7, 14, 21, and 28 days postexposure revealed distinct lesions, as defined by increased standardized uptake values (SUV). Increased SUV showed high spatial correspondence to immunohistochemical evidence of neuroinflammation, which was corroborated by cytokine gene and protein expression. Regional SUV metrics varied spatiotemporally with days postexposure and correlated with the degree of neuroinflammation detected immunohistochemically. Furthermore, SUV metrics were highly correlated with seizure severity, suggesting that early termination of OP-induced seizures may be critical for attenuating subsequent neuroinflammatory responses. Normalization of SUV values to a cerebellar reference region improved correlations to all outcome measures and seizure severity. Collectively, these results establish TSPO PET using [18F]PBR111 as a robust, noninvasive tool for longitudinal monitoring of neuroinflammation following acute OP intoxication.
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Affiliation(s)
- Brad A Hobson
- Department of Radiology, University of California Davis School of Medicine, Sacramento, California 95817
| | - Douglas J Rowland
- Center for Molecular and Genomic Imaging, Department of Biomedical Engineering, University of California Davis College of Engineering, Davis, California 95616
| | - Sílvia Sisó
- Department of Pathology, Microbiology and Immunology
| | - Michelle A Guignet
- Department of Molecular Biosciences, University of California Davis School of Veterinary Medicine, Davis, California 95616
| | - Zachary T Harmany
- Center for Molecular and Genomic Imaging, Department of Biomedical Engineering, University of California Davis College of Engineering, Davis, California 95616
| | - Suren B Bandara
- Department of Molecular Biosciences, University of California Davis School of Veterinary Medicine, Davis, California 95616
| | - Naomi Saito
- Department of Public Health Sciences, University of California Davis School of Medicine, Davis, California 95616
| | - Danielle J Harvey
- Department of Public Health Sciences, University of California Davis School of Medicine, Davis, California 95616
| | - Donald A Bruun
- Department of Molecular Biosciences, University of California Davis School of Veterinary Medicine, Davis, California 95616
| | - Joel R Garbow
- Department of Radiology, Washington University in St. Louis, St. Louis, Missouri 63110
| | - Abhijit J Chaudhari
- Department of Radiology, University of California Davis School of Medicine, Sacramento, California 95817.,Center for Molecular and Genomic Imaging, Department of Biomedical Engineering, University of California Davis College of Engineering, Davis, California 95616
| | - Pamela J Lein
- Department of Molecular Biosciences, University of California Davis School of Veterinary Medicine, Davis, California 95616
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