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Qiu L, Jiang H, Zhou C, Tangadanchu VKR, Wang J, Huang T, Gropler RJ, Perlmutter JS, Benzinger TLS, Tu Z. Design, synthesis, and biological evaluation of multiple F-18 S1PR1 radiotracers in rodent and nonhuman primate. Org Biomol Chem 2024. [PMID: 38884683 DOI: 10.1039/d4ob00712c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2024]
Abstract
Here we report our design and synthesis of 28 new fluorine-containing compounds as potential F-18 radiotracers for CNS imaging of sphingosine-1-phosphate receptor 1 (S1PR1), and determination of their in vitro binding potency and selectivity toward S1PR1 over other S1PR subtypes. Nine potent and selective compounds, 7c&d, 9a&c, 12b, 15b, and 18a-c with IC50 values ranging from 0.6-12.3 nM for S1PR1 and weak binding toward S1PR2, 3, 4, and 5, were further 18F-radiolabeled to produce [18F]7c&d, [18F]9a&c, [18F]12b, [18F]15b, and [18F]18a-c. Multi-step F-18 radiochemistry procedures were investigated for radiosynthesis of [18F]7c&d and [18F]9a&c, and the presumed intermediates were synthesized and authenticated by analytic HPLC. We then performed nonhuman primate (NHP) PET brain imaging studies for eight radiotracers: [18F]7c&d, [18F]9a, [18F]12b, [18F]15b, and [18F]18a-c. Three radiotracers, [18F]7c, [18F]7d, and [18F]15b, had high NHP brain uptake with standardized uptake values (SUVs) at 2 h post-injection of 2.42, 2.84, and 2.00, respectively, and good brain retention. Our ex vivo biodistribution study in rats confirmed [18F]7d had a high brain uptake with no in vivo defluorination. Radiometabolic analysis of [18F]7c and [18F]7d in rat plasma and brain samples found that [18F]7c has a more favorable metabolic profile than [18F]7d. However, the trend of increased brain uptake precludes [18F]7c as a suitable PET radiotracer for imaging S1PR1 in the brain. Further structural optmization is warranted to identify a highly S1PR1-specific radiotracer with rapid brain uptake kinetics.
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Affiliation(s)
- Lin Qiu
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
| | - Hao Jiang
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
| | - Charles Zhou
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
| | | | - Jinzhi Wang
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
| | - Tianyu Huang
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
| | - Robert J Gropler
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
| | - Joel S Perlmutter
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
- Department of Neurology, Neuroscience, Physical Therapy and Occupational Therapy, Washington University School of Medicine, Saint Louis, Missouri, 63110, USA
| | - Tammie L S Benzinger
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
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Gu J, Zheng MQ, Holden D, Fowles K, Qiu L, Felchner Z, Zhang L, Ropchan J, Gropler RJ, Carson RE, Tu Z, Huang Y, Hillmer AT. PET Imaging of Sphingosine-1-Phosphate Receptor 1 with [18F]TZ4877 in Nonhuman Primates. RESEARCH SQUARE 2024:rs.3.rs-4350862. [PMID: 38854065 PMCID: PMC11160920 DOI: 10.21203/rs.3.rs-4350862/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Purpose The sphingosine-1-phosphate receptor-1 (S1PR1) is involved in regulating responses to neuroimmune stimuli. There is a need for S1PR1-specific radioligands with clinically suitable brain pharmcokinetic properties to complement existing radiotracers. This work evaluated a promising S1PR1 radiotracer, [18F]TZ4877, in nonhuman primates. Procedures [18F]TZ4877 was produced via nucleophilic substitution of tosylate precursor with K[18F]/F- followed by deprotection. Brain PET imaging data were acquired with a Focus220 scanner in two Macaca mulatta (6, 13 years old) for 120-180 min following bolus injection of 118-163 MBq [18F]TZ4877, with arterial blood sampling and metabolite analysis to measure the parent input function and plasma free fraction (f P). Each animal was scanned at baseline, 15-18 min after 0.047-0.063 mg/kg of the S1PR1 inhibitor ponesimod, 33 min after 0.4-0.8 mg/kg of the S1PR1-specific compound TZ82112, and 167-195 min after 1 ng/kg of the immune stimulus endotoxin. Kinetic analysis with metabolite-corrected input function was performed to estimate the free fraction corrected total distribution volume (V T/f P). Whole-body dosimetry scans were acquired in 2 animals (1M, 1F) with a Biograph Vision PET/CT System, and absorbed radiation dose estimates were calculated with OLINDA. Results [18F]TZ4877 exhibited fast kinetics that were described by the reversible 2-tissue compartment model. Baseline [18F]TZ4877 f P was low (< 1%), and [18F]TZ4877 V T/f P values were 233-866 mL/cm3. TZ82112 dose-dependently reduced [18F]TZ4877 V T/f P, while ponesimod and endotoxin exhibited negligible effects on V T/f P, possibly due to scan timing relative to dosing. Dosimetry studies identified the critical organs of gallbladder (0.42 (M) and 0.31 (F) mSv/MBq) for anesthetized nonhuman primate. Conclusions [18F]TZ4877 exhibits reversible kinetic properties, but the low f P value limits quantification with this radiotracer. S1PR1 is a compelling PET imaging target, and these data support pursuing alternative F-18 labeled radiotracers for potential future human studies.
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Affiliation(s)
| | | | | | | | - Lin Qiu
- Washington University School of Medicine in Saint Louis: Washington University in St Louis School of Medicine
| | | | | | | | - Robert J Gropler
- Washington University School of Medicine in Saint Louis: Washington University in St Louis School of Medicine
| | | | - Zhude Tu
- Washington University School of Medicine in Saint Louis: Washington University in St Louis School of Medicine
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Qiu L, Jiang H, Cho K, Yu Y, Jones LA, Huang T, Perlmutter JS, Gropler RJ, Brier MR, Patti GJ, Benzinger TLS, Tu Z. Metabolite Study and Structural Authentication for the First-in-Human Use Sphingosine-1-phosphate Receptor 1 Radiotracer. ACS Chem Neurosci 2024; 15:1882-1892. [PMID: 38634759 PMCID: PMC11103254 DOI: 10.1021/acschemneuro.4c00077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024] Open
Abstract
The sphingosine-1-phosphate receptor 1 (S1PR1) radiotracer [11C]CS1P1 has shown promise in proof-of-concept PET imaging of neuroinflammation in multiple sclerosis (MS). Our HPLC radiometabolite analysis of human plasma samples collected during PET scans with [11C]CS1P1 detected a radiometabolite peak that is more lipophilic than [11C]CS1P1. Radiolabeled metabolites that cross the blood-brain barrier complicate quantitative modeling of neuroimaging tracers; thus, characterizing such radiometabolites is important. Here, we report our detailed investigation of the metabolite profile of [11C]CS1P1 in rats, nonhuman primates, and humans. CS1P1 is a fluorine-containing ligand that we labeled with C-11 or F-18 for preclinical studies; the brain uptake was similar for both radiotracers. The same lipophilic radiometabolite found in human studies also was observed in plasma samples of rats and NHPs for CS1P1 labeled with either C-11 or F-18. We characterized the metabolite in detail using rats after injection of the nonradioactive CS1P1. To authenticate the molecular structure of this radiometabolite, we injected rats with 8 mg/kg of CS1P1 to collect plasma for solvent extraction and HPLC injection, followed by LC/MS analysis of the same metabolite. The LC/MS data indicated in vivo mono-oxidation of CS1P1 produces the metabolite. Subsequently, we synthesized three different mono-oxidized derivatives of CS1P1 for further investigation. Comparing the retention times of the mono-oxidized derivatives with the metabolite observed in rats injected with CS1P1 identified the metabolite as N-oxide 1, also named TZ82121. The MS fragmentation pattern of N-oxide 1 also matched that of the major metabolite in rat plasma. To confirm that metabolite TZ82121 does not enter the brain, we radiosynthesized [18F]TZ82121 by the oxidation of [18F]FS1P1. Radio-HPLC analysis confirmed that [18F]TZ82121 matched the radiometabolite observed in rat plasma post injection of [18F]FS1P1. Furthermore, the acute biodistribution study in SD rats and PET brain imaging in a nonhuman primate showed that [18F]TZ82121 does not enter the rat or nonhuman primate brain. Consequently, we concluded that the major lipophilic radiometabolite N-oxide [11C]TZ82121, detected in human plasma post injection of [11C]CS1P1, does not enter the brain to confound quantitative PET data analysis. [11C]CS1P1 is a promising S1PR1 radiotracer for detecting S1PR1 expression in the CNS.
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Affiliation(s)
- Lin Qiu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Hao Jiang
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Kevin Cho
- Center for Mass Spectrometry and Metabolic Tracing, Department of Chemistry, Department of Medicine, Washington University, Saint Louis, Missouri 63130, United States
| | - Yanbo Yu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Lynne A Jones
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Tianyu Huang
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Joel S Perlmutter
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
- Departments of Neurology, Neuroscience, Physical Therapy and Occupational Therapy, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Robert J Gropler
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Matthew R Brier
- Departments of Neurology, Neuroscience, Physical Therapy and Occupational Therapy, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Gary J Patti
- Center for Mass Spectrometry and Metabolic Tracing, Department of Chemistry, Department of Medicine, Washington University, Saint Louis, Missouri 63130, United States
| | - Tammie L S Benzinger
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
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Prasad VP, Wagner S, Keul P, Hermann S, Levkau B, Schäfers M, Haufe G. Synthesis, radiosynthesis and biochemical evaluation of fluorinated analogues of sphingosine-1-phosphate receptor 3 specific antagonists using PET. Bioorg Med Chem 2024; 104:117697. [PMID: 38599005 DOI: 10.1016/j.bmc.2024.117697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 02/21/2024] [Accepted: 03/22/2024] [Indexed: 04/12/2024]
Abstract
Sphingosine-1-phosphate and its receptors (S1PRs) are involved in several diseases such as auto immunity, inflammation and cardiovascular disorders. The S1P analogue fingolimod (Gilenya®) is currently in use for the treatment of relapsing multiple sclerosis. S1PRs are also promising targets for clinical molecular imaging in vivo. The organ distribution of individual S1PRs can be potentially achieved by using S1PR subtype-specific (radiolabeled) chemical probes. Here, we report our efforts on synthesis and in vivo potency determination of new ligands for the S1P receptor 3 (S1P3) based on the S1P3 antagonist TY-52156 and in validation of a potential imaging tracer in vivo using Positron Emission Tomography (PET) after 18F-labelling. A p-fluorophenyl derivative exhibited excellent S1P3 antagonist activity in vitro, good serum stability, and medium lipophilicity. In vivo biodistribution experiments using 18F-PET exhibited significant uptake in the myocardium suggesting potential applications in cardiac imaging.
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Affiliation(s)
- Vysakh Puspha Prasad
- Organic Chemistry Institute, University of Münster, Corrensstraße 40, 48149 Münster, Germany; NRW Graduate School of Chemistry, University of Münster, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany
| | - Stefan Wagner
- Department of Nuclear Medicine, University Hospital Münster, Albert-Schweitzer-Campus 1, 48149 Münster, Germany
| | - Petra Keul
- Institute of Molecular Medicine III, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Sven Hermann
- European Institute for Molecular Imaging (EIMI), University of Münster, Multiscale Imaging Centre, Röntgenstraße 16, 48149 Münster, Germany
| | - Bodo Levkau
- Institute of Molecular Medicine III, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Michael Schäfers
- Department of Nuclear Medicine, University Hospital Münster, Albert-Schweitzer-Campus 1, 48149 Münster, Germany; European Institute for Molecular Imaging (EIMI), University of Münster, Multiscale Imaging Centre, Röntgenstraße 16, 48149 Münster, Germany; Cells-in-Motion Interfaculty Centre, University of Münster, Röntgenstraße 16, 48149 Münster, Germany
| | - Günter Haufe
- Organic Chemistry Institute, University of Münster, Corrensstraße 40, 48149 Münster, Germany; NRW Graduate School of Chemistry, University of Münster, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany; European Institute for Molecular Imaging (EIMI), University of Münster, Multiscale Imaging Centre, Röntgenstraße 16, 48149 Münster, Germany; Cells-in-Motion Interfaculty Centre, University of Münster, Röntgenstraße 16, 48149 Münster, Germany.
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Etebar F, Harkin DG, White AR, Dando SJ. Non-invasive in vivo imaging of brain and retinal microglia in neurodegenerative diseases. Front Cell Neurosci 2024; 18:1355557. [PMID: 38348116 PMCID: PMC10859418 DOI: 10.3389/fncel.2024.1355557] [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: 12/14/2023] [Accepted: 01/10/2024] [Indexed: 02/15/2024] Open
Abstract
Microglia play crucial roles in immune responses and contribute to fundamental biological processes within the central nervous system (CNS). In neurodegenerative diseases, microglia undergo functional changes and can have both protective and pathogenic roles. Microglia in the retina, as an extension of the CNS, have also been shown to be affected in many neurological diseases. While our understanding of how microglia contribute to pathological conditions is incomplete, non-invasive in vivo imaging of brain and retinal microglia in living subjects could provide valuable insights into their role in the neurodegenerative diseases and open new avenues for diagnostic biomarkers. This mini-review provides an overview of the current brain and retinal imaging tools for studying microglia in vivo. We focus on microglia targets, the advantages and limitations of in vivo microglia imaging approaches, and applications for evaluating the pathogenesis of neurological conditions, such as Alzheimer's disease and multiple sclerosis.
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Affiliation(s)
- Fazeleh Etebar
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD, Australia
- Mental Health and Neuroscience Program, QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Damien G. Harkin
- Centre for Vision and Eye Research, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD, Australia
| | - Anthony R. White
- Mental Health and Neuroscience Program, QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Samantha J. Dando
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD, Australia
- Centre for Vision and Eye Research, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD, Australia
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Jiang H, Zhou C, Qiu L, Gropler RJ, Brier MR, Wu GF, Cross AH, Perlmutter JS, Benzinger TLS, Tu Z. Quantitative Analysis of S1PR1 Expression in the Postmortem Multiple Sclerosis Central Nervous System. ACS Chem Neurosci 2023; 14:4039-4050. [PMID: 37882753 PMCID: PMC11037862 DOI: 10.1021/acschemneuro.3c00581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023] Open
Abstract
Multiple sclerosis (MS) is an immune-mediated disease that is characterized by demyelination and inflammation in the central nervous system (CNS). Previous studies demonstrated that sphingosine-1-phosphate receptor (S1PR) modulators effectively inhibit S1PR1 in immune cell trafficking and reduce entry of pathogenic cells into the CNS. Studies have also implicated a nonimmune, inflammatory role of S1PR1 within the CNS in MS. In this study, we explored the expression of S1PR1 in the development and progression of demyelinating pathology of MS by quantitative assessment of S1PR1 expression using our S1PR1-specific radioligand, [3H]CS1P1, in the postmortem human CNS tissues including cortex, cerebellum, and spinal cord of MS cases and age- and sex-matched healthy cases. Immunohistochemistry with whole slide scanning for S1PR1 and various myelin proteins was also performed. Autoradiographic analysis using [3H]CS1P1 showed that the expression of S1PR1 was statistically significantly elevated in lesions compared to nonlesion regions in the MS cases, as well as normal healthy controls. The uptake of [3H]CS1P1 in the gray matter and nonlesion white matter did not significantly differ between healthy and MS CNS tissues. Saturation autoradiography analysis showed an increased binding affinity (Kd) of [3H]CS1P1 to S1PR1 in both gray matter and white matter of MS brains compared to healthy brains. Our blocking study using NIBR-0213, a S1PR1 antagonist, indicated [3H]CS1P1 is highly specific to S1PR1. Our findings demonstrated the activation of S1PR1 and an increased uptake of [3H]CS1P1 in the lesions of MS CNS. In summary, our quantitative autoradiography analysis using [3H]CS1P1 on human postmortem tissues shows the feasibility of novel imaging strategies for MS by targeting S1PR1.
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Affiliation(s)
- Hao Jiang
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Charles Zhou
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Lin Qiu
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Robert J Gropler
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Matthew R Brier
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Gregory F Wu
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Anne H Cross
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Joel S Perlmutter
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Tammie L S Benzinger
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
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Qiu L, Jiang H, Zhou C, Wang J, Yu Y, Zhao H, Huang T, Gropler R, Perlmutter JS, Benzinger TLS, Tu Z. Discovery of a Promising Fluorine-18 Positron Emission Tomography Radiotracer for Imaging Sphingosine-1-Phosphate Receptor 1 in the Brain. J Med Chem 2023; 66:4671-4688. [PMID: 36926861 PMCID: PMC11037415 DOI: 10.1021/acs.jmedchem.2c01752] [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] [Indexed: 03/18/2023]
Abstract
Sphingosine-1-phosphate receptor 1 (S1PR1) is recognized as a novel therapeutic and diagnostic target in neurological disorders. We recently transferred the S1PR1 radioligand [11C]CS1P1 into clinical investigation for multiple sclerosis. Herein, we reported the design, synthesis and evaluation of novel F-18 S1PR1 radioligands. We combined the structural advantages of our two lead S1PR1 radioligands and synthesized 14 new S1PR1 compounds, then performed F-18 radiochemistry on the most promising compounds. Compound 6h is potent (IC50 = 8.7 nM) and selective for S1PR1. [18F]6h exhibited a high uptake in macaque brain (SUV > 3.0) and favorable brain washout pharmacokinetics in positron emission tomography (PET) study. PET blocking and displacement studies confirmed the specificity of [18F]6h in vivo. Radiometabolite analysis confirmed no radiometabolite of [18F]6h entered into the brain to confound the PET measurement. In summary, [18F]6h is a promising radioligand to image S1PR1 and worth translational clinical investigation for humans with brain disorders.
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Affiliation(s)
- Lin Qiu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Hao Jiang
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Charles Zhou
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Jinzhi Wang
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Yanbo Yu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Haiyang Zhao
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Tianyu Huang
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Robert Gropler
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Joel S Perlmutter
- Department of Neurology, Radiology, Neuroscience, Physical Therapy and Occupational Therapy, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Tammie L S Benzinger
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
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Dysregulation of sphingosine-1-phosphate (S1P) and S1P receptor 1 signaling in the 5xFAD mouse model of Alzheimer's disease. Brain Res 2023; 1799:148171. [PMID: 36410428 DOI: 10.1016/j.brainres.2022.148171] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 10/22/2022] [Accepted: 11/15/2022] [Indexed: 11/19/2022]
Abstract
Sphingolipid-1-phosphate (S1P) signaling through the activation S1P receptors (S1PRs) plays critical roles in cellular events in the brain. Aberrant S1P metabolism has been identified in the brains of Alzheimer's disease (AD) patients. Our recent studies have shown that treatment with fingolimod, an analog of sphingosine, provides neuroprotective effects in five familiar Alzheimer disease (5xFAD) transgenic mice, resulting in the reduction of amyloid-β (Aβ) neurotoxicity, inhibition of activation of microglia and astrocytes, increased hippocampal neurogenesis, and improved learning and memory. However, the pathways by which dysfunctional S1P and S1PR signaling may associate with the development of AD-like pathology remain unknown. In this study, we investigated the alteration of signaling of S1P/S1P receptor 1 (S1PR1), the most abundant S1PR subtype in the brain, in the cortex of 5xFAD transgenic mice at 3, 8, and 14 months of age. Compared to non-transgenic wildtype (WT) littermates, we found significant decreased levels of sphingosine kinases (SphKs), increased S1P lyase (S1PL), and increased S1PR1 in 8- and 14-month-old, but not in 3-month-old 5xFAD mice. Furthermore, we detected increased activation of the S1PR1 downstream pathway of Akt/mTor/Tau signaling in aging 5xFAD mice. Treatment with fingolimod from 1 to 8 months of age reversed the levels of SphKs, S1PL, and furthermore, those of S1PR1 and its downstream pathway of Akt/mTor/Tau signaling. Together the data reveal that dysregulation of S1P and S1PR signaling may associate with the development of AD-like pathology through Akt/mTor/Tau signaling.
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Brier MR, Hamdi M, Rajamanikam J, Zhao H, Mansor S, Jones LA, Rahmani F, Jindal S, Koudelis D, Perlmutter JS, Wong DF, Nickels M, Ippolito JE, Gropler RJ, Schindler TH, Laforest R, Tu Z, Benzinger TLS. Phase 1 Evaluation of 11C-CS1P1 to Assess Safety and Dosimetry in Human Participants. J Nucl Med 2022; 63:1775-1782. [PMID: 35332093 PMCID: PMC9635683 DOI: 10.2967/jnumed.121.263189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 03/02/2022] [Indexed: 01/07/2023] Open
Abstract
This study evaluated the safety, dosimetry, and characteristics of 3-((2-fluoro-4-(5-(2'-methyl-2-(trifluoromethyl)-[1,1'-biphenyl]-4-yl)-1,2,4-oxadiazol-3-yl)benzyl)(methyl-11C)amino)propanoic acid (11C-CS1P1), a radiotracer targeting sphingosine-1-phosphate receptor (S1PR) 1 (S1PR1). S1PR1 is of clinical interest because of its role in multiple sclerosis (and other conditions), with an expanding class of S1PR modulators approved for relapsing multiple sclerosis. 11C-CS1P1 binds S1PR1 with high specificity and has shown promise in animal models of inflammatory diseases. Methods: 11C-CS1P1 was injected into 5 male and 6 female healthy participants. Ten participants were imaged with PET using a multipass whole-body continuous-bed-motion acquisition, and one had dedicated head and neck PET and MRI. Participants were continuously monitored for safety events. Organ time-activity curve data were collected, integrated, and normalized to the injected activity. Organ radiation doses and effective dose were computed using the adult male and female models in OLINDA, version 2.2. SUV images were evaluated for qualitative biodistribution. Results: No adverse events were observed after the dose, including no bradycardia. The liver was the critical organ from dosimetry analysis (mean ± SD: female, 23.12 ± 5.19 μSv/MBq; male, 21.06 ± 1.63 μSv/MBq). The whole-body effective dose (as defined by International Commission on Radiological Protection publication 103) was 4.18 ± 0.30 μSv/MBq in women and 3.54 ± 0.14 μSv/MBq in men. Using a maximum delivered dose of 740 MBq (20 mCi), the effective dose for women would be 3.1 mSv (0.31 rem), with a liver dose of 17.1 mSv (1.7 rem); the effective dose for men would be 2.6 mSv (0.26 rem), with a liver dose of 15.6 mSv (1.56 rem). Brain uptake was seen predominantly in gray matter and correlated with regional S1PR1 RNA expression (r = 0.84). Conclusion: These results support the safety of 11C-CS1P1 for evaluation of inflammation in human clinical populations. Dosimetry permits repeated measures in the same participants. Brain uptake correlates well with known target topography.
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Affiliation(s)
- Matthew R Brier
- Department of Neurology, Washington University, St. Louis, Missouri
| | - Mahdjoub Hamdi
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | | | - Haiyang Zhao
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Syahir Mansor
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Lynne A Jones
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Farzaneh Rahmani
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Saurabh Jindal
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Deborah Koudelis
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Joel S Perlmutter
- Department of Neurology, Washington University, St. Louis, Missouri
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
- Department of Neuroscience, Washington University, St. Louis, Missouri
- Department of Physical and Occupational Therapy, Washington University, St. Louis, Missouri; and
| | - Dean F Wong
- Department of Neurology, Washington University, St. Louis, Missouri
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
- Department of Neuroscience, Washington University, St. Louis, Missouri
- Department of Psychiatry, Washington University, St. Louis, Missouri
| | - Michael Nickels
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Joseph E Ippolito
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Robert J Gropler
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Thomas H Schindler
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Richard Laforest
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
| | - Zhude Tu
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri;
| | - Tammie L S Benzinger
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri;
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10
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Chand GB, Jiang H, Miller JP, Rhodes CH, Tu Z, Wong DF. Differential Sphingosine-1-Phosphate Receptor-1 Protein Expression in the Dorsolateral Prefrontal Cortex Between Schizophrenia Type 1 and Type 2. Front Psychiatry 2022; 13:827981. [PMID: 35350429 PMCID: PMC8957823 DOI: 10.3389/fpsyt.2022.827981] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 02/03/2022] [Indexed: 11/25/2022] Open
Abstract
Understanding the etiology and treatment approaches in schizophrenia is challenged in part by the heterogeneity of this disorder. One encouraging progress is the growing evidence that there are subtypes of schizophrenia. Recent in vitro findings of messenger ribonucleic acid (mRNA) gene expression on postmortem dorsolateral prefrontal cortex (DLPFC) showed that schizophrenia has two subtypes, those with a relatively normal DLPFC transcriptome (Type 1) and those with differentially expressed genes (Type 2). Sphingosine-1-phosphate receptor-1 (S1PR1) is one of the genes that was highly upregulated in Type 2 compared to Type 1 and controls. The impact of that finding is limited because it only can be confirmed through analysis of autopsy tissue, and the clinical characteristics such as symptoms severity or illness duration except for cause of death was not available from that Medical Examiner based autopsy study. However, S1PR1 has great potential because it is a target gene that can be accessed via positron emission tomography (PET) in vivo using specific radioligands (starting with [11C]CS1P1) successfully developed at our center in human brain imaging. As a preliminary study to validate this PET target in schizophrenia, S1PR1 protein expression was assessed by receptor autoradiography (ARG) using [3H]CS1P1 and immunohistochemistry (IHC) in the DLPFC from patients with schizophrenia classified as Type 1 or Type 2 based on their DLPFC transcriptomes and from controls. Our analyses demonstrate that ARG S1PR1 protein expression is significantly higher in Type 2 compared to Type 1 (p < 0.05) and controls (p < 0.05), which was consistent with previous mRNA S1PR1. These findings support the possibility that PET S1PR1 can be used as a future imaging biomarker to distinguish these subgroups of schizophrenic patients during life with obvious implications for both patient management and the design of clinical trials to validate novel pharmacologic therapies.
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Affiliation(s)
- Ganesh B. Chand
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Hao Jiang
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, United States
| | - J. Philip Miller
- Division of Biostatistics, Washington University School of Medicine, St. Louis, MO, United States
| | | | - Zhude Tu
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Dean Foster Wong
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, United States
- Department of Psychiatry, Neuroscience, and Neurology, Washington University School of Medicine, St. Louis, MO, United States
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11
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Qiu L, Jiang H, Yu Y, Gu J, Wang J, Zhao H, Huang T, Gropler RJ, Klein RS, Perlmutter JS, Tu Z. Radiosynthesis and evaluation of a fluorine-18 radiotracer [ 18F]FS1P1 for imaging sphingosine-1-phosphate receptor 1. Org Biomol Chem 2022; 20:1041-1052. [PMID: 35029272 PMCID: PMC8970350 DOI: 10.1039/d1ob02225c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Assessment of sphingosine-1-phosphate receptor 1 (S1PR1) expression could be a unique tool to determine the neuroinflammatory status for central nervous system (CNS) disorders. Our preclinical results indicate that PET imaging with [11C]CS1P1 radiotracer can quantitatively measure S1PR1 expression changes in different animal models of inflammatory diseases. Here we developed a multiple step F-18 labeling strategy to synthesize the radiotracer [18F]FS1P1, sharing the same structure with [11C]CS1P1. We explored a wide range of reaction conditions for the nucleophilic radiofluorination starting with the key ortho-nitrobenzaldehyde precursor 10. The tertiary amine additive TMEDA proved crucial to achieve high radiochemical yield of ortho-[18F]fluorobenzaldehyde [18F]12 starting with a small amount of precursor. Based on [18F]12, a further four-step modification was applied in one-pot to generate the target radiotracer [18F]FS1P1 with 30-50% radiochemical yield, >95% chemical and radiochemical purity, and a high molar activity (37-166.5 GBq μmol-1, decay corrected to end of synthesis, EOS). Subsequently, tissue distribution of [18F]FS1P1 in rats showed a high brain uptake (ID% g-1) of 0.48 ± 0.06 at 5 min, and bone uptake of 0.27 ± 0.03, 0.11 ± 0.02 at 5, and 120 min respectively, suggesting no in vivo defluorination. MicroPET studies showed [18F]FS1P1 has high macaque brain uptake with a standard uptake value (SUV) of ∼2.3 at 120 min. Radiometabolite analysis of macaque plasma samples indicated that [18F]FS1P1 has good metabolic stability, and no major radiometabolite confounded PET measurements of S1PR1 in nonhuman primate brain. Overall, [18F]FS1P1 is a promising F-18 S1PR1 radiotracer worthy of further clinical investigation for human use.
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Affiliation(s)
- Lin Qiu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
| | - Hao Jiang
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
| | - Yanbo Yu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
| | - Jiwei Gu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
| | - Jinzhi Wang
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
| | - Haiyang Zhao
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
| | - Tianyu Huang
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
| | - Robert J Gropler
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
| | - Robyn S Klein
- Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110, USA
- Departments of Neuroscience, Washington University School of Medicine, Saint Louis, MO 63110, USA
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Joel S Perlmutter
- Departments of Neuroscience, Washington University School of Medicine, Saint Louis, MO 63110, USA
- Department of Neurology, Washington University School of Medicine, Saint Louis, MO 63110, USA
- Physical Therapy and Occupational Therapy, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
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12
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Nutma E, Ceyzériat K, Amor S, Tsartsalis S, Millet P, Owen DR, Papadopoulos V, Tournier BB. Cellular sources of TSPO expression in healthy and diseased brain. Eur J Nucl Med Mol Imaging 2021; 49:146-163. [PMID: 33433698 PMCID: PMC8712293 DOI: 10.1007/s00259-020-05166-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 12/13/2020] [Indexed: 12/11/2022]
Abstract
The 18 kDa translocator protein (TSPO) is a highly conserved protein located in the outer mitochondrial membrane. TSPO binding, as measured with positron emission tomography (PET), is considered an in vivo marker of neuroinflammation. Indeed, TSPO expression is altered in neurodegenerative, neuroinflammatory, and neuropsychiatric diseases. In PET studies, the TSPO signal is often viewed as a marker of microglial cell activity. However, there is little evidence in support of a microglia-specific TSPO expression. This review describes the cellular sources and functions of TSPO in animal models of disease and human studies, in health, and in central nervous system diseases. A discussion of methods of analysis and of quantification of TSPO is also presented. Overall, it appears that the alterations of TSPO binding, their cellular underpinnings, and the functional significance of such alterations depend on many factors, notably the pathology or the animal model under study, the disease stage, and the involved brain regions. Thus, further studies are needed to fully determine how changes in TSPO binding occur at the cellular level with the ultimate goal of revealing potential therapeutic pathways.
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Affiliation(s)
- Erik Nutma
- Department of Pathology, Amsterdam UMC, VUmc, Amsterdam, The Netherlands
| | - Kelly Ceyzériat
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland
- Division of Nuclear medicine and Molecular Imaging, University Hospitals of Geneva, Geneva, Switzerland
- Division of Radiation Oncology, Department of Oncology, University Hospitals of Geneva, Geneva, Switzerland
| | - Sandra Amor
- Department of Pathology, Amsterdam UMC, VUmc, Amsterdam, The Netherlands
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine & Dentistry, Queen Mary University of London, London, UK
| | - Stergios Tsartsalis
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Philippe Millet
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland
- Department of Psychiatry, University of Geneva, Geneva, Switzerland
| | - David R Owen
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Vassilios Papadopoulos
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Benjamin B Tournier
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland.
- Department of Psychiatry, University of Geneva, Geneva, Switzerland.
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13
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Luo G, Wang X, Cui Y, Cao Y, Zhao Z, Zhang J. Metabolic reprogramming mediates hippocampal microglial M1 polarization in response to surgical trauma causing perioperative neurocognitive disorders. J Neuroinflammation 2021; 18:267. [PMID: 34774071 PMCID: PMC8590219 DOI: 10.1186/s12974-021-02318-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 11/07/2021] [Indexed: 01/27/2023] Open
Abstract
Background Microglial polarization toward pro-inflammatory M1 phenotype are major contributors to the development of perioperative neurocognitive disorders (PNDs). Metabolic reprogramming plays an important role in regulating microglial polarization. We therefore hypothesized that surgical trauma can activate microglial M1 polarization by metabolic reprogramming to induce hippocampal neuroinflammation and subsequent postoperative cognitive impairment. Methods We used aged mice to establish a model of PNDs, and investigated whether surgical trauma induced metabolic reprograming in hippocampus using PET/CT and GC/TOF–MS based metabolomic analysis. We then determined the effect of the glycolytic inhibitor 2-deoxy-d-glucose (2-DG) on hippocampal microglial M1 polarization, neuroinflammation, and cognitive function at 3 d after surgery. Results We found that surgery group had less context-related freezing time than either control or anesthesia group (P < 0.05) without significant difference in tone-related freezing time (P > 0.05). The level of Iba-1 fluorescence intensity in hippocampus were significantly increased in surgery group than that in control group (P < 0.05) accompanied by activated morphological changes of microglia and increased expression of iNOS/CD86 (M1 marker) in enriched microglia from hippocampus (P < 0.05). PET/CT and metabolomics analysis indicated that surgical trauma provoked the metabolic reprogramming from oxidative phosphorylation to glycolysis in hippocampus. Inhibition of glycolysis by 2-DG significantly alleviated the surgical trauma induced increase of M1 (CD86+CD206−) phenotype in enriched microglia from hippocampus and up-regulation of pro-inflammatory mediators (IL-1β and IL-6) expression in hippocampus. Furthermore, glycolytic inhibition by 2-DG ameliorated the hippocampus dependent cognitive deficit caused by surgical trauma. Conclusions Metabolic reprogramming is crucial for regulating hippocampal microglial M1 polarization and neuroinflammation in PNDs. Manipulating microglial metabolism might provide a valuable therapeutic strategy for treating PNDs. Surgical trauma impaired the hippocampus-dependent contextual memory in age mice. Surgical trauma induced microglial M1 polarization and subsequent neuroinflammation. Metabolic reprogramming was crucial for regulating microglial M1 polarization in PNDs. Modulating microglial metabolism might provide a valuable approach for treating PNDs.
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Affiliation(s)
- Gang Luo
- Department of Anesthesiology, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University, 600 Yishan Road, Shanghai, 200233, China
| | - Xiaofeng Wang
- Department of Anesthesiology, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University, 600 Yishan Road, Shanghai, 200233, China
| | - Yongchen Cui
- Department of Anesthesiology, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University, 600 Yishan Road, Shanghai, 200233, China
| | - Yue Cao
- Department of Anesthesiology, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University, 600 Yishan Road, Shanghai, 200233, China
| | - Zhe Zhao
- Department of Geriatrics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University, 600 Yishan Road, Shanghai, 200233, China.
| | - Junfeng Zhang
- Department of Anesthesiology, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University, 600 Yishan Road, Shanghai, 200233, China.
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14
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Jiang H, Joshi S, Liu H, Mansor S, Qiu L, Zhao H, Whitehead T, Gropler RJ, Wu GF, Cross AH, Benzinger TLS, Shoghi KI, Perlmutter JS, Tu Z. In Vitro and In Vivo Investigation of S1PR1 Expression in the Central Nervous System Using [ 3H]CS1P1 and [ 11C]CS1P1. ACS Chem Neurosci 2021; 12:3733-3744. [PMID: 34516079 PMCID: PMC8605766 DOI: 10.1021/acschemneuro.1c00492] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Sphingosine-1-phosphate receptor 1 (S1PR1) is ubiquitously expressed among all tissues and plays key roles in many physiological and cellular processes. In the central nervous system (CNS), S1PR1 is expressed in different types of cells including neurons, astrocytes, and oligodendrocyte precursor cells. S1PR1 has been recognized as a novel therapeutic target in multiple sclerosis and other diseases. We previously reported a promising S1PR1-specific radioligand, [11C]CS1P1 (previously named [11C]TZ3321), which is under clinical investigation for human use. In the current study, we performed a detailed characterization of [3H]CS1P1 for its binding specificity to S1PR1 in CNS using autoradiography and immunohistochemistry in human and rat CNS tissues. Our data indicate that [3H]CS1P1 binds to S1PR1 in human frontal cortex tissue with a Kd of 3.98 nM and a Bmax of 172.5 nM. The distribution of [3H]CS1P1 in human and rat CNS tissues is consistent with the distribution of S1PR1 detected by immunohistochemistry studies. Our microPET studies of [11C]CS1P1 in a nonhuman primate (NHP) show a standardized uptake value of 2.4 in the NHP brain, with test-retest variability of 0.23% among six different NHPs. Radiometabolite analysis in the plasma samples of NHP and rat, as well as in rat brain samples, showed that [11C]CS1P1 was stable in vivo. Kinetic modeling studies using a two-compartment tissue model showed that the positron emission tomography (PET) data fit the model well. Overall, our study provides a detailed characterization of [3H]CS1P1 binding to S1PR1 in the CNS. Combined with our microPET studies in the NHP brain, our data suggest that [11C]CS1P1 is a promising radioligand for PET imaging of S1PR1 in the CNS.
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Affiliation(s)
- Hao Jiang
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Sumit Joshi
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Hui Liu
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Syahir Mansor
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Lin Qiu
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Haiyang Zhao
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Timothy Whitehead
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Robert J. Gropler
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Gregory F. Wu
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Anne H. Cross
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Tammie L. S. Benzinger
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Kooresh I. Shoghi
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Joel S. Perlmutter
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri 63110, United States
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri 63110, United States
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15
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Jiang H, Gu J, Zhao H, Joshi S, Perlmutter JS, Gropler RJ, Klein RS, Benzinger TLS, Tu Z. PET Study of Sphingosine-1-phosphate Receptor 1 Expression in Response to S. aureus Infection. Mol Imaging 2021; 2021:9982020. [PMID: 34934406 PMCID: PMC8654346 DOI: 10.1155/2021/9982020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 09/02/2021] [Indexed: 11/22/2022] Open
Abstract
Sphingosine-1-phosphate receptor 1 (S1PR1) plays a crucial role in infectious diseases. Targeting S1PR1 provides protection against pathogens, such as influenza viruses. This study is aimed at investigating S1PR1 in response to bacterial infection by assessing S1PR1 expression in S. aureus-infected mice. A rodent local muscle bacterial infection model was developed by injecting S. aureus to the lower hind limb of Balb/c mice. The changes of S1PR1 expression in response to bacterial infection and blocking treatment were assessed using ex vivo biodistribution and in vivo positron emission tomography (PET) after intravenous injection of an S1PR1-specific radiotracer [18F]TZ4877. The specificity of [18F]TZ4877 was assessed using S1PR1-specific antagonist, NIBR-0213, and S1PR1-specific DsiRNA pretreated the animals. Immunohistochemical studies were performed to confirm the increase of S1PR1 expression in response to infection. Ex vivo biodistribution data showed that the uptake of [18F]TZ4877 was increased 30.6%, 54.3%, 74.3%, and 115.3% in the liver, kidney, pancreas, and thymus of the infected mice, respectively, compared to that in normal control mice, indicating that S1PR1 is involved in the early immune response to bacterial infection. NIBR-0213 or S1PR1-specific DsiRNA pretreatment reduced the tissue uptake of [18F]TZ4877, suggesting that uptake of [18F]TZ4877 is specific. Our PET/CT study data also confirmed that infected mice have increased [18F]TZ4877 uptake in several organs comparing to that in normal control mice. Particularly, compared to control mice, a 39% increase of [18F]TZ4877 uptake was observed in the infected muscle of S. aureus mice, indicating that S1PR1 expression was directly involved in the inflammatory response to infection. Overall, our study suggested that S1PR1 plays an important role in the early immune response to bacterial infection. The uptake of [18F]TZ4877 is tightly correlated with the S1R1 expression in response to S. aureus infection. PET with S1PR1-specific radiotracer [18F]TZ4877 could provide a noninvasive tool for detecting the early S1PR1 immune response to infectious diseases.
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Affiliation(s)
- Hao Jiang
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Jiwei Gu
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Haiyang Zhao
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Sumit Joshi
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Joel S. Perlmutter
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
- Department of Neuroscience, Neurology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Robert J. Gropler
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Robyn S. Klein
- Department of Neuroscience, Neurology, Washington University School of Medicine, St Louis, MO 63110, USA
- Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Tammie L. S. Benzinger
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
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16
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Selkirk JV, Dines KC, Yan YG, Ching N, Dalvie D, Biswas S, Bortolato A, Schkeryantz JM, Lopez C, Ruiz I, Hargreaves R. Deconstructing the Pharmacological Contribution of Sphingosine-1 Phosphate Receptors to Mouse Models of Multiple Sclerosis Using the Species Selectivity of Ozanimod, a Dual Modulator of Human Sphingosine-1 Phosphate Receptor Subtypes 1 and 5. J Pharmacol Exp Ther 2021; 379:386-399. [PMID: 34535564 DOI: 10.1124/jpet.121.000741] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 08/26/2021] [Indexed: 11/22/2022] Open
Abstract
Ozanimod, a sphingosine-1 phosphate (S1P) receptor modulator that binds with high affinity selectively to S1P receptor subtypes 1 (S1P1) and 5 (S1P5), is approved for the treatment of relapsing multiple sclerosis (MS) in multiple countries. Ozanimod profiling revealed a species difference in its potency for S1P5 in mouse, rat, and canine compared with that for human and monkey. Site-directed mutagenesis identified amino acid alanine at position 120 to be responsible for loss of activity for mouse, rat, and canine S1P5 and mutation back to threonine as in human/monkey S1P5 restored activity. Radioligand binding analysis performed with mouse S1P5 confirmed the potency loss is a consequence of a loss of affinity of ozanimod for mouse S1P5 and was restored with mutation of alanine 120 to threonine. Study of ozanimod in preclinical mouse models of MS can now determine the S1P receptor(s) responsible for observed efficacies with receptor engagement as measured using pharmacokinetic exposures of free drug. Hence, in the experimental autoimmune encephalomyelitis model, ozanimod exposures sufficient to engage S1P1, but not S1P5, resulted in reduced circulating lymphocytes, disease scores, and body weight loss; reduced inflammation, demyelination, and apoptotic cell counts in the spinal cord; and reduced circulating levels of the neuronal degeneration marker, neurofilament light. In the demyelinating cuprizone model, ozanimod prevented axonal degradation and myelin loss during toxin challenge but did not facilitate enhanced remyelination post-intoxication. Since free drug levels in this model only engaged S1P1, we concluded that S1P1 activation is neuroprotective but does not appear to affect remyelination. Significance Statement Ozanimod, a selective human S1P1/5 modulator, displays reduced potency for rodent and dog S1P5 compared with human, which results from mutation of threonine to alanine at position 120. Ozanimod can thus be used as a selective S1P1 agonist in mouse models of multiple sclerosis to define efficacies driven by S1P1 but not S1P5 Based on readouts for experimental autoimmune encephalomyelitis and cuprizone intoxication, S1P1 modulation is neuroprotective but S1P5 activity may be required for remyelination.
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Affiliation(s)
| | | | | | | | - Deepak Dalvie
- Building 2, Crinetics Pharmaceuticals, United States
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17
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Ye M, Gai Y, Ji H, Jiang Y, Qiao P, Wang W, Zhang Y, Xia X, Lan X. A Novel Radioimmune 99mTc-Labeled Tracer for Imaging Sphingosine 1-Phosphate Receptor 1 in Tumor Xenografts: An In Vitro and In Vivo Study. Front Immunol 2021; 12:660842. [PMID: 34484174 PMCID: PMC8416251 DOI: 10.3389/fimmu.2021.660842] [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: 01/29/2021] [Accepted: 08/03/2021] [Indexed: 11/13/2022] Open
Abstract
Sphingosine-1-phosphate (S1P) is a phospholipid that regulates pleiotropic biological activities and exerts extracellular functions by binding to five specific G-protein-coupled receptors, S1P receptors (S1PR) 1-5. When activated by S1P, S1PR promote the proliferation and invasion of tumor cells by inducing the formation of new blood vessels. We developed and assessed a new monoclonal antibody imaging probe 99mTc-HYNIC-S1PR1mAb, to explore the feasibility of targeting the S1PR1 in vitro and in vivo. S1PR1mAb was prepared and followed by technetium-99m labeling with succinimidyl 6-hydraziniumnicotinate hydrochloride. Cell uptake and blocking studies were performed to investigate the binding specificity of 99mTc-HYNIC-S1PR1mAb in vitro. 99mTc-HYNIC-S1P1mAb was also tested in vivo in mice xenografted with SK-HEP-1 (high-expression of S1PR1) and MCF-7 (low-expression of S1PR1) using single-photon emission-computed tomography (SPECT). Ex vivo gamma counting of tissues from tumor-bearing mice was used to evaluate 99mTc-HYNIC-S1PR1mAb biodistribution. The biodistribution study results showed significantly higher uptake in SK-HEP-1 tumors than in MCF-7 tumors (P < 0.001). Reduced uptake of 99mTc-HYNIC-S1PR1mAb in SK-HEP-1 was observed in tumor-bearing nude mice pretreated with fingolimod, which binds competitively to the receptors, especially S1PR1. 99mTc-HYNIC-S1PR1mAb can be synthesized and specifically targeted to S1PR1 in vitro and in vivo, allowing S1PR1 expression assessment with SPECT imaging.
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Affiliation(s)
- Min Ye
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Yongkang Gai
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Hao Ji
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Yaqun Jiang
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Pengxin Qiao
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Wenxia Wang
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Yongxue Zhang
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Xiaotian Xia
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Xiaoli Lan
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
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18
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Liu H, Luo Z, Gu J, Jiang H, Joshi S, Shoghi KI, Zhou Y, Gropler RJ, Benzinger TLS, Tu Z. In vivo Characterization of Four 18F-Labeled S1PR1 Tracers for Neuroinflammation. Mol Imaging Biol 2021; 22:1362-1369. [PMID: 32602083 PMCID: PMC7679043 DOI: 10.1007/s11307-020-01514-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
PURPOSE The sphingosine-1-phosphate receptor 1 (S1PR1) is an important biomarker for imaging inflammation in the central nervous system (CNS). Herein, we report our recent evaluation of four 18F-labeled S1PR1 tracers (18F-TZ43113, 18F-TZ35104, 18F-TZ4877, and 18F-TZ4881) in a rat model of multiple sclerosis (MS). PROCEDURES MicroPET studies of each tracer's uptake and kinetics were performed in an experimental autoimmune encephalomyelitis (EAE) rat model of MS to quantify upregulated S1PR1 expression in the lumbar spinal cord of EAE rats. Western blot analysis was conducted to confirm the differences in the expression of S1PR1 protein level between EAE and sham rats. Radiometabolite analysis was performed for the most promising candidate in rats. RESULTS All four S1PR1 tracers detected increased S1PR1 levels in response to neuroinflammation in the lumbar spinal cord of EAE rats, which was supported by western blot results. The ranked order of tracer uptake in rat spinal cord was 18F-TZ4877 > 18F-TZ4881 > 18F-TZ35104 > 18F-TZ43113. 18F-TZ4877 had the highest uptake of the four tracers and showed good kinetic modeling fits in rat spinal cord using an image-based method of arterial blood input function. Radiometabolite analysis of 18F-TZ4877 showed good in vivo stability with no major radiometabolite accumulation in the rat brain. CONCLUSION Among these four new PET tracers, 18F-TZ4877 showed the most favorable profile for assessing S1PR1 expression in the EAE rat model of MS. Further characterization of these radiotracers in other models of neuroinflammation is warranted to identify a promising 18F-labeled tracer for imaging S1PR1 in vivo.
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Affiliation(s)
- Hui Liu
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Zonghua Luo
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Jiwei Gu
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Hao Jiang
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Sumit Joshi
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Kooresh I Shoghi
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Yun Zhou
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Robert J Gropler
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Tammie L S Benzinger
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA.
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19
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Activation of sphingosine-1-phosphate receptor subtype 1 in the central nervous system contributes to morphine-induced hyperalgesia and antinociceptive tolerance in rodents. Pain 2021; 161:2107-2118. [PMID: 32301840 DOI: 10.1097/j.pain.0000000000001888] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/30/2020] [Indexed: 12/31/2022]
Abstract
ABSTRACT Morphine-induced alterations in sphingolipid metabolism in the spinal cord and increased formation of the bioactive sphingolipid metabolite sphingosine-1-phosphate (S1P) have been implicated in the development of morphine-induced hyperalgesia (OIH; increased pain sensitivity) and antinociceptive tolerance. These adverse effects hamper opioid use for treating chronic pain and contribute to dependence and abuse. S1P produces distinct effects through 5 G-protein-coupled receptors (S1PR1-5) and several intracellular targets. How S1P exerts its effects in response to morphine remains unknown. Here, we report that S1P contributes to the development of morphine-induced hyperalgesia and tolerance through S1P receptor subtype 1 (S1PR1) signaling in uninjured male and female rodents, which can be blocked by targeting S1PR1 with S1PR1 antagonists or RNA silencing. In mouse neuropathic pain models, S1PR1 antagonists blocked the development of tolerance to the antiallodynic effects of morphine without altering morphine pharmacokinetics and prevented prolonged morphine-induced neuropathic pain. Targeting S1PR1 reduced morphine-induced neuroinflammatory events in the dorsal horn of the spinal cord: increased glial marker expression, mitogen-activated protein kinase p38 and nuclear factor κB activation, and increased inflammatory cytokine expression, such as interleukin-1β, a cytokine central in the modulation of opioid-induced neural plasticity. Our results identify S1PR1 as a critical path for S1P signaling in response to sustained morphine and reveal downstream neuroinflammatory pathways impacted by S1PR1 activation. Our data support investigating S1PR1 antagonists as a clinical approach to mitigate opioid-induced adverse effects and repurposing the functional S1PR1 antagonist FTY720, which is FDA-approved for multiple sclerosis, as an opioid adjunct.
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20
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Acute Rodent Tolerability, Toxicity, and Radiation Dosimetry Estimates of the S1P1-Specific Radioligand [ 11C]CS1P1. Mol Imaging Biol 2021; 22:285-292. [PMID: 31165387 PMCID: PMC6893109 DOI: 10.1007/s11307-019-01380-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE In preclinical studies with rodent models of inflammatory diseases, [11C]CS1P1 has been identified as a promising imaging agent targeting sphingosine-1-phosphate receptor 1 (S1P1) in the central nervous system and other tissues. In preparation for USA Food and Drug Administration (FDA) approval of [11C]CS1P1 for human use, an acute biodistribution study in mice and an acute tolerability and toxicity evaluation in rats were conducted. PROCEDURES Acute organ biodistribution and excretion data was obtained using male and female Swiss Webster mice intravenously (IV) injected with 4.8-10 MBq of [11C]CS1P1. The organ residence times for each harvested organ were calculated using the animal biodistribution data, and were entered in the program OLINDA/EXM for C-11 to obtain human radiation dosimetry estimates. Acute tolerability and toxicity studies were conducted in male and female Sprague Dawley rats. Rats were administered an IV bolus of either the vehicle control or 0.3 mg/kg CS1P1. Blood samples were collected and a gross post-mortem examination was conducted at day 2 or day 15 post-injection. RESULTS The extrapolated human radiation dose estimates revealed that the highest organ dose was received by the liver with 24.05 μGy/MBq in males and 32.70 μGy/MBq in females. The effective dose (ED) estimates of [11C]CS1P1 were calculated at 3.5 μSv/MBq in males and 5.9 μSv/MBq in females. The acute tolerability and toxicity study identified 0.3 mg/kg as a no observable adverse effect level (NOAEL) dose, which is a ~ 300-fold dose multiple of the human equivalent dose of the mass to be injected for positron emission tomography (PET) imaging studies in humans as a no-observable-effect limit. CONCLUSIONS The toxicity study in rats suggested that injection dose of radiotracer [11C]CS1P1 with mass amount < 10 μg is safe for performing a human PET study. The dosimetry data supported an injection of 0.74 GBq (20 mCi) dose for human studies would be acceptable.
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21
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Yao Q, Guan J, Ma L, Cheng L, Duan F, Xu F, Zhao W, Duan W, Wu H, Chen Z, Jian F. Wireless Epidural Electrical Stimulation in Combination With Serotonin Agonists Improves Intraspinal Metabolism in Spinal Cord Injury Rats. Neuromodulation 2020; 24:416-426. [PMID: 33377590 DOI: 10.1111/ner.13344] [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] [Received: 05/26/2020] [Revised: 11/14/2020] [Accepted: 11/30/2020] [Indexed: 12/25/2022]
Abstract
OBJECTIVES The combination of epidural electrical stimulation (EES) and serotonin agonists (5-HTA) effectively restores rhythmic lower-limb movements and improves intraspinal hemodynamics after spinal cord injury (SCI). Nonetheless, whether EES + 5-HTA improves intraspinal metabolism remains unclear. The present study aimed to evaluate the effects of EES + 5-HTA on intraspinal metabolism in SCI rats. MATERIALS AND METHODS Wireless EES (WEES) implantation with complete T8 transection was performed in SCI rats. Electrodes were placed at the T12 and L2 vertebral levels. After rest for a week, the SCI rats received 11 weeks of WEES + 5-HTA treatment and treadmill training. WEES was switched off after each daily training. Locomotor function was evaluated by motion capture at week 12. Positron emission tomography-computed tomography was conducted to evaluate basal metabolism when WEES was switched off and assess task metabolism when WEES was switched on. RESULTS With locomotor recovery after training for 11 weeks, WEES + 5-HTA conjointly improved basal metabolism (vs. each intervention alone; p < 0.05) and linearly modulated task metabolism in a frequency-dependent manner (R2 = 0.8901). Furthermore, 60 Hz of WEES was identified as the threshold for the extensive activation of the spinal cord's task metabolism below the transection plane (p < 0.05). CONCLUSIONS WEES + 5-HTA could conjointly restore basal metabolism to a healthy level and modulate task metabolism by adjusting the stimulation frequency.
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Affiliation(s)
- Qingyu Yao
- Department of Neurosurgery, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China.,Research Center of Spine and Spinal Cord, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Jian Guan
- Department of Neurosurgery, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China.,Research Center of Spine and Spinal Cord, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Longbing Ma
- Department of Neurosurgery, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China.,Research Center of Spine and Spinal Cord, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Lei Cheng
- Department of Neurosurgery, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China.,Research Center of Spine and Spinal Cord, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Feng Duan
- College of Artificial Intelligence, Nankai University, Tianjin, China
| | - Fu Xu
- School of Aerospace Engineering, Tsinghua University, Beijing, China
| | - Wang Zhao
- Department of Management Science, University of Strathclyde, Glasgow, UK
| | - Wanru Duan
- Department of Neurosurgery, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China.,Research Center of Spine and Spinal Cord, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Hao Wu
- Department of Neurosurgery, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China.,Research Center of Spine and Spinal Cord, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Zan Chen
- Department of Neurosurgery, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China.,Research Center of Spine and Spinal Cord, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Fengzeng Jian
- Department of Neurosurgery, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China.,Research Center of Spine and Spinal Cord, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Xuanwu Hospital, Capital Medical University, Beijing, China
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22
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Kipp M. Does Siponimod Exert Direct Effects in the Central Nervous System? Cells 2020; 9:cells9081771. [PMID: 32722245 PMCID: PMC7463861 DOI: 10.3390/cells9081771] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/21/2020] [Accepted: 07/22/2020] [Indexed: 12/11/2022] Open
Abstract
The modulation of the sphingosine 1-phosphate receptor is an approved treatment for relapsing multiple sclerosis because of its anti-inflammatory effect of retaining lymphocytes in lymph nodes. Different sphingosine 1-phosphate receptor subtypes are expressed in the brain and spinal cord, and their pharmacological effects may improve disease development and neuropathology. Siponimod (BAF312) is a novel sphingosine 1-phosphate receptor modulator that has recently been approved for the treatment of active secondary progressive multiple sclerosis (MS). In this review article, we summarize recent evidence suggesting that the active role of siponimod in patients with progressive MS may be due to direct interaction with central nervous system cells. Additionally, we tried to summarize our current understanding of the function of siponimod and discuss the effects observed in the case of MS.
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Affiliation(s)
- Markus Kipp
- Institute of Anatomy, Rostock University Medical Center, Gertrudenstrasse 9, 18057 Rostock, Germany
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23
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Chen R, Cao X, Luo W, Yang H, Luo X, Yu J, Luo J. Dabigatran Suppresses PAR-1/SphK/S1P Activation of Astrocytes in Experimental Autoimmune Encephalomyelitis Model. Front Mol Neurosci 2020; 13:114. [PMID: 32694981 PMCID: PMC7338760 DOI: 10.3389/fnmol.2020.00114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 06/03/2020] [Indexed: 12/30/2022] Open
Abstract
Multiple sclerosis (MS) is an inflammatory autoimmune disease affecting the central nervous system (CNS) that currently does not have any effective treatment. Experimental autoimmune encephalomyelitis (EAE) is often employed as a model to mimic the clinical manifestations of MS, mainly CNS demyelination. Coagulation is known to participate in crosstalk with inflammation and autoimmunity. We herein explored the correlation between the coagulation cascade and CNS immune diseases in vitro using primary astrocytes isolated from mice and in vivo using a mouse model of EAE. We showed that dabigatran, a clinical oral anti-coagulant drug, suppressed the thrombin-induced activation of astrocytes, and the underlying mechanisms are related to the activity of protease-activated receptor-1 (PAR-1), sphingosine-1-phosphate (S1P), and sphingosine kinases (SphKs). Importantly, dabigatran effectively recovered neurological function, reduced inflammation in the spinal cord, and prevented spinal cord demyelination caused by EAE. We suggest that dabigatran, a specific inhibitor of thrombin, antagonized the effect of thrombin in astrocytes by limiting the activation of PAR-1, in turn downregulating SphK1 and disrupting S1P receptor signaling. These findings reveal critical information about the relationship between coagulation mechanisms and CNS immune diseases and will contribute to the clinical translation and development of therapeutic strategies against MS.
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Affiliation(s)
- Rong Chen
- Department of Microbiology and Immunology, North Sichuan Medical College, Nanchong, China
| | - Xing Cao
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Wenxiu Luo
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Haodi Yang
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Xinya Luo
- Department of Anesthesia, North Sichuan Medical College, Nanchong, China
| | - Juming Yu
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Jiaming Luo
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China.,School of Psychiatry, North Sichuan Medical College, Nanchong, China
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24
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Abarca-Zabalía J, García MI, Lozano Ros A, Marín-Jiménez I, Martínez-Ginés ML, López-Cauce B, Martín-Barbero ML, Salvador-Martín S, Sanjurjo-Saez M, García-Domínguez JM, López Fernández LA. Differential Expression of SMAD Genes and S1PR1 on Circulating CD4+ T Cells in Multiple Sclerosis and Crohn's Disease. Int J Mol Sci 2020; 21:ijms21020676. [PMID: 31968593 PMCID: PMC7014376 DOI: 10.3390/ijms21020676] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 01/12/2020] [Accepted: 01/16/2020] [Indexed: 01/13/2023] Open
Abstract
The Th17 immune response plays a key role in autoimmune diseases such as multiple sclerosis (MS) and inflammatory bowel disease (IBD). Expression of Th17-related genes in inflamed tissues has been reported in autoimmune diseases. However, values are frequently obtained using invasive methods. We aimed to identify biomarkers of MS in an accessible sample, such as blood, by quantifying the relative expression of 91 Th17-related genes in CD4+ T lymphocytes from patients with MS during a relapse or during a remitting phase. We also compared our findings with those of healthy controls. After confirmation in a validation cohort, expression of SMAD7 and S1PR1 mRNAs was decreased in remitting disease (-2.3-fold and -1.3-fold, respectively) and relapsing disease (-2.2-fold and -1.3-fold, respectively). No differential expression was observed for other SMAD7-related genes, namely, SMAD2, SMAD3, and SMAD4. Under-regulation of SMAD7 and S1PR1 was also observed in another autoimmune disease, Crohn's disease (CD) (-4.6-fold, -1.6-fold, respectively), suggesting the presence of common markers for autoimmune diseases. In addition, expression of TNF, SMAD2, SMAD3, and SMAD4 were also decreased in CD (-2.2-fold, -1.4-fold, -1.6-fold, and -1.6-fold, respectively). Our study suggests that expression of SMAD7 and S1PR1 mRNA in blood samples are markers for MS and CD, and TNF, SMAD2, SMAD3, and SMAD4 for CD. These genes could prove useful as markers of autoimmune diseases, thus obviating the need for invasive methods.
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Affiliation(s)
- Judith Abarca-Zabalía
- Servicio de Farmacia, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (J.A.-Z.); (M.L.M.-B.); (S.S.-M.); (M.S.-S.)
| | - Ma Isabel García
- Servicio de Farmacia, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (J.A.-Z.); (M.L.M.-B.); (S.S.-M.); (M.S.-S.)
| | - Alberto Lozano Ros
- Servicio de Neurología, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (A.L.R.); (M.L.M.-G.)
| | - Ignacio Marín-Jiménez
- Unidad de Enfermedad Inflamatoria Intestinal, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (I.M.-J.); (B.L.-C.)
| | - Maria L. Martínez-Ginés
- Servicio de Neurología, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (A.L.R.); (M.L.M.-G.)
| | - Beatriz López-Cauce
- Unidad de Enfermedad Inflamatoria Intestinal, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (I.M.-J.); (B.L.-C.)
| | - María L. Martín-Barbero
- Servicio de Farmacia, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (J.A.-Z.); (M.L.M.-B.); (S.S.-M.); (M.S.-S.)
| | - Sara Salvador-Martín
- Servicio de Farmacia, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (J.A.-Z.); (M.L.M.-B.); (S.S.-M.); (M.S.-S.)
| | - María Sanjurjo-Saez
- Servicio de Farmacia, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (J.A.-Z.); (M.L.M.-B.); (S.S.-M.); (M.S.-S.)
| | - Jose M. García-Domínguez
- Servicio de Neurología, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (A.L.R.); (M.L.M.-G.)
- Correspondence: (J.M.G.-D.); (L.A.L.F.)
| | - Luis A. López Fernández
- Servicio de Farmacia, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, 28007 Madrid, Spain; (J.A.-Z.); (M.L.M.-B.); (S.S.-M.); (M.S.-S.)
- Correspondence: (J.M.G.-D.); (L.A.L.F.)
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25
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Luo Z, Gu J, Dennett RC, Gaehle GG, Perlmutter JS, Chen DL, Benzinger TLS, Tu Z. Automated production of a sphingosine-1 phosphate receptor 1 (S1P1) PET radiopharmaceutical [ 11C]CS1P1 for human use. Appl Radiat Isot 2019; 152:30-36. [PMID: 31280104 DOI: 10.1016/j.apradiso.2019.06.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 06/17/2019] [Accepted: 06/19/2019] [Indexed: 10/26/2022]
Abstract
Automated synthesis of a radiopharmaceutical 3-((2-fluoro-4-(5-(2'-methyl-2-(trifluoromethyl)-[1,1'-biphenyl]-4-yl)-1,2,4-oxadiazol-3-yl)benzyl) (methyl-11C)amino)propanoic acid ([11C]CS1P1) for PET imaging sphingosine-1 phosphate receptor 1 (S1P1) was accomplished by a two-step-one-pot procedure in a Siemens CTI methylation automated module using TR-19 cyclotron. The synthesis of [11C]CS1P1 was successfully validated under current Good Manufacturing Practices (cGMP) conditions, resulting in a consistent average radiochemical yield of ∼15%, molar activity of ∼3129 GBq/μmol (decay corrected to end of bombardment, EOB), and radiochemical purity > 95%. The radiopharmaceutical product meets all quality control criteria for human use for an Investigational New Drug (IND) application to permit human studies.
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Affiliation(s)
- Zonghua Luo
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Jiwei Gu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Robert C Dennett
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Gregory G Gaehle
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Joel S Perlmutter
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA; Department of Neurology, Neuroscience, Physical Therapy and Occupational Therapy, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Delphine L Chen
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Tammie L S Benzinger
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA.
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26
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Bauckneht M, Capitanio S, Raffa S, Roccatagliata L, Pardini M, Lapucci C, Marini C, Sambuceti G, Inglese M, Gallo P, Cecchin D, Nobili F, Morbelli S. Molecular imaging of multiple sclerosis: from the clinical demand to novel radiotracers. EJNMMI Radiopharm Chem 2019; 4:6. [PMID: 31659498 PMCID: PMC6453990 DOI: 10.1186/s41181-019-0058-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 03/21/2019] [Indexed: 12/13/2022] Open
Abstract
Background Brain PET imaging with different tracers is mainly clinically used in the field of neurodegenerative diseases and brain tumors. In recent years, the potential usefulness of PET has also gained attention in the field of MS. In fact, MS is a complex disease and several processes can be selected as a target for PET imaging. The use of PET with several different tracers has been mainly evaluated in the research setting to investigate disease pathophysiology (i.e. phenotypes, monitoring of progression) or to explore its use a surrogate end-point in clinical trials. Results We have reviewed PET imaging studies in MS in humans and animal models. Tracers have been grouped according to their pathophysiological targets (ie. tracers for myelin kinetic, neuroinflammation, and neurodegeneration). The emerging clinical indication for brain PET imaging in the differential diagnosis of suspected tumefactive demyelinated plaques as well as the clinical potential provided by PET images in view of the recent introduction of PET/MR technology are also addressed. Conclusion While several preclinical and fewer clinical studies have shown results, full-scale clinical development programs are needed to translate molecular imaging technologies into a clinical reality that could ideally fit into current precision medicine perspectives.
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Affiliation(s)
- Matteo Bauckneht
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy.
| | - Selene Capitanio
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy
| | - Stefano Raffa
- Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy
| | - Luca Roccatagliata
- Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy.,Neuroradiology, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Matteo Pardini
- Clinical Neurology, Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy.,Clinica Neurologica, IRCCS Ospedale Policlinico, San Martino, Genoa, Italy
| | - Caterina Lapucci
- Clinical Neurology, Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy
| | - Cecilia Marini
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy.,CNR Institute of Molecular Bioimaging and Physiology, Milan, Italy
| | - Gianmario Sambuceti
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy.,Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy
| | - Matilde Inglese
- Clinical Neurology, Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy.,Clinica Neurologica, IRCCS Ospedale Policlinico, San Martino, Genoa, Italy
| | - Paolo Gallo
- Multiple Sclerosis Centre of the Veneto Region, Department of Neurosciences DNS, University of Padua, Padua, Italy
| | - Diego Cecchin
- Nuclear Medicine Unit, Department of Medicine-DIMED, Padova University Hospital, Padua, Italy.,Padua Neuroscience Center, University of Padua, Padua, Italy
| | - Flavio Nobili
- Clinical Neurology, Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy.,Clinica Neurologica, IRCCS Ospedale Policlinico, San Martino, Genoa, Italy
| | - Silvia Morbelli
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy.,Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy
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Luo Z, Han J, Liu H, Rosenberg AJ, Chen DL, Gropler RJ, Perlmutter JS, Tu Z. Syntheses and in vitro biological evaluation of S1PR1 ligands and PET studies of four F-18 labeled radiotracers in the brain of nonhuman primates. Org Biomol Chem 2019; 16:9171-9184. [PMID: 30462126 DOI: 10.1039/c8ob02609b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A series of seventeen hydroxyl-containing sphingosine 1-phosphate receptor 1 (S1PR1) ligands were designed and synthesized. Their in vitro binding potencies were determined using [32P]S1P competitive binding assays. Compounds 10a, 17a, 17b, and 24 exhibited high S1PR1 binding potencies with IC50 values ranging from 3.9 to 15.4 nM and also displayed high selectivity for S1PR1 over other S1P receptor subtypes (IC50 > 1000 nM for S1PR2-5). The most potent compounds 10a, 17a, 17b, and 24 were subsequently radiolabeled with F-18 in high yields and purities. MicroPET studies in cynomolgus macaque showed that [18F]10a, [18F]17a, and [18F]17b but not [18F]24 crossed the blood brain barrier and had high initial brain uptake. Further validation of [18F]10a, [18F]17a, and [18F]17b in preclinical models of neuroinflammation is warranted to identify a suitable PET radioligand to quantify S1PR1 expression in vivo as a metric of an inflammatory response.
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Affiliation(s)
- Zonghua Luo
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, St Louis, Missouri 63110, USA.
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Liu H, Jin H, Han J, Yue X, Yang H, Zayed MA, Gropler RJ, Tu Z. Upregulated Sphingosine 1-Phosphate Receptor 1 Expression in Human and Murine Atherosclerotic Plaques. Mol Imaging Biol 2019; 20:448-456. [PMID: 29134505 DOI: 10.1007/s11307-017-1141-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE Dysregulation of sphingosine 1-phosphate receptor 1 (S1PR1) signaling contributes to inflammation-related pathophysiological changes in cardiovascular diseases including atherosclerosis (AS). S1PR1-targeting compounds significantly reduce lesion size in murine models of AS. Therefore, characterization of S1PR1 expression in vitro and in vivo in atherosclerotic plaque could enable mechanistic studies and inform S1PR1 targeted therapies. PROCEDURES H&E staining and immunostaining studies were performed on variably diseased human femoral endarterectomy plaque specimens, as well as mouse aortic sections from ApoE-/- mice maintained on a high-fat diet (AS mice). In vitro autoradiography study in human femoral plaques was used to confirm the tracer specificity. Micro positron emission tomography (PET) and ex vivo autoradiography studies were conducted in AS mice and their controls using a S1PR1-specific radioligand [11C]TZ3321 for in vivo and ex vivo quantification of S1PR1 expression in mouse aortic plaques. RESULTS Increased S1PR1 expression was observed in areas of human femoral endarterectomy plaque specimens with foam cell accumulation compared with control tissue; in vitro autoradiography study indicated that SEW2781, a S1PR1 compound was able to reduce the uptake of [11C]TZ3321 by 56 %. S1PR1 levels were also upregulated in AS mouse aortic plaques. MicroPET data showed the aorta-to-blood tracer uptake ratio in AS mice was approximately 20 % higher than that in controls. Autoradiographic study also revealed elevated tracer accumulation in AS mouse aorta. CONCLUSIONS Upregulated S1PR1 expression in human and mouse atherosclerotic plaques was successfully identified by immunostaining and radioligand-based methods. This data demonstrates that [11C]TZ3321 PET provides great promise in imaging S1PR1 expression in atherosclerotic plaques.
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Affiliation(s)
- Hui Liu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Hongjun Jin
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Junbin Han
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Xuyi Yue
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Hao Yang
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Mohamed A Zayed
- Department of Surgery, Section of Vascular Surgery, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Robert J Gropler
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA.
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29
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Franco Machado J, Silva RD, Melo R, G Correia JD. Less Exploited GPCRs in Precision Medicine: Targets for Molecular Imaging and Theranostics. Molecules 2018; 24:E49. [PMID: 30583594 PMCID: PMC6337414 DOI: 10.3390/molecules24010049] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 12/07/2018] [Accepted: 12/09/2018] [Indexed: 12/18/2022] Open
Abstract
Precision medicine relies on individually tailored therapeutic intervention taking into account individual variability. It is strongly dependent on the availability of target-specific drugs and/or imaging agents that recognize molecular targets and patient-specific disease mechanisms. The most sensitive molecular imaging modalities, Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET), rely on the interaction between an imaging radioprobe and a target. Moreover, the use of target-specific molecular tools for both diagnostics and therapy, theranostic agents, represent an established methodology in nuclear medicine that is assuming an increasingly important role in precision medicine. The design of innovative imaging and/or theranostic agents is key for further accomplishments in the field. G-protein-coupled receptors (GPCRs), apart from being highly relevant drug targets, have also been largely exploited as molecular targets for non-invasive imaging and/or systemic radiotherapy of various diseases. Herein, we will discuss recent efforts towards the development of innovative imaging and/or theranostic agents targeting selected emergent GPCRs, namely the Frizzled receptor (FZD), Ghrelin receptor (GHSR-1a), G protein-coupled estrogen receptor (GPER), and Sphingosine-1-phosphate receptor (S1PR). The pharmacological and clinical relevance will be highlighted, giving particular attention to the studies on the synthesis and characterization of targeted molecular imaging agents, biological evaluation, and potential clinical applications in oncology and non-oncology diseases. Whenever relevant, supporting computational studies will be also discussed.
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Affiliation(s)
- João Franco Machado
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
| | - Rúben D Silva
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
| | - Rita Melo
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
- Center for Neuroscience and Cell Biology; Rua Larga, Faculdade de Medicina, Polo I, 1ºandar, Universidade de Coimbra, 3004-504 Coimbra, Portugal.
| | - João D G Correia
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
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30
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Luo Z, Rosenberg AJ, Liu H, Han J, Tu Z. Syntheses and in vitro evaluation of new S1PR1 compounds and initial evaluation of a lead F-18 radiotracer in rodents. Eur J Med Chem 2018; 150:796-808. [PMID: 29604582 PMCID: PMC5908474 DOI: 10.1016/j.ejmech.2018.03.035] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 02/27/2018] [Accepted: 03/12/2018] [Indexed: 12/15/2022]
Abstract
Thirteen new sphingosine-1-phosphate receptor 1 (S1PR1) ligands were designed and synthesized by replacing azetidine-3-carboxylic acid moiety of compound 4 with new polar groups. The in vitro binding potency of these new analogs toward S1PR1 was determined. Out of 13 new compounds, four compounds 9a, 10c, 12b, and 16b displayed high S1PR1 binding potency with IC50 values of 13.2 ± 3.2, 14.7 ± 1.7, 9.7 ± 1.6, and 6.3 ± 1.3 nM, respectively; further binding studies of these four ligands toward S1PR2-5 suggested they are highly selective for S1PR1 over other S1PRs. The radiosynthesis of the lead radiotracer [18F]12b was achieved with good radiochemical yield (∼14.1%), high radiochemical purity (>98%), and good specific activity (∼54.1 GBq/μmol, decay corrected to the end of synthesis, EOS). Ex vivo autoradiography and initial biodistribution studies in rodents were performed, suggesting that [18F]12b was able to penetrate the blood-brain barrier (BBB) with high brain uptake (0.71% ID/g at 60 min post-injection) and no defluorination was observed. In vitro autoradiography study in brain slices of lipopolysaccharides (LPS)-induced neuroinflammation mice indicated that SEW2871, a specific S1PR1 ligand was able to reduce the uptake of [18F]12b, suggesting [18F]12b has S1PR1 specific binding. These initial results suggested that [18F]12b has potential to be an F-18 labeled radiotracer for imaging S1PR1 in the brain of the animal in vivo.
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Affiliation(s)
- Zonghua Luo
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Adam J Rosenberg
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hui Liu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Junbin Han
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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31
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Liu H, Jin H, Yue X, Han J, Baum P, Abendschein DR, Tu Z. PET Study of Sphingosine-1-Phosphate Receptor 1 Expression in Response to Vascular Inflammation in a Rat Model of Carotid Injury. Mol Imaging 2018; 16:1536012116689770. [PMID: 28654378 PMCID: PMC5470136 DOI: 10.1177/1536012116689770] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Sphingosine-1-phosphate receptor (S1PR) activation plays a key role in vascular inflammatory response. Here, we report in vivo validation of [11C]TZ3321, a potent S1PR1 radioligand, for imaging vascular inflammation in a rat model of carotid injury. The right common carotid artery of male adult Sprague-Dawley rats was injured by balloon overinflation that denuded the endothelium and distended the vessel wall. Animals received a 60-minute micro-positron emission tomography (micro PET) scan with [11C]TZ3321 at 72 hours after injury. Ex vivo autoradiography was also conducted. The expression and cellular location of S1PR1 were examined by immunohistological analysis. Three-dimensional (3D) reconstruction of the first 100-second microPET/computed tomography (CT) image indicated the location of bilateral common carotid arteries. [11C]TZ3321 displayed significantly higher accumulation (standardized uptake values: 0.93 ± 0.07 vs 0.78 ± 0.09, n = 6, P = .001) in the injured carotid artery than in the contralateral side. Increased tracer uptake in the injured artery was confirmed by autoradiography (photostimulated luminescence measures: 85.5 ± 0.93 vs 71.48 ± 6.22, n = 2). Concordantly, high S1PR1expression was observed in infiltrated inflammatory cells in the injured artery. Our studies demonstrate [11C]TZ3321 microPET is able to detect the acute upregulation of S1PR1 expression in inflamed carotid artery. Therefore, [11C]TZ3321 has potential to be a PET radiotracer for detecting early inflammatory response and monitoring therapeutic efficacy of vascular inflammation.
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Affiliation(s)
- Hui Liu
- 1 Department of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Hongjun Jin
- 1 Department of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Xuyi Yue
- 1 Department of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Junbin Han
- 1 Department of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Pamela Baum
- 2 Center for Cardiovascular Research, Department of Internal Medicine, Washington University School of Medicine, St Louis, MO, USA
| | - Dana R Abendschein
- 2 Center for Cardiovascular Research, Department of Internal Medicine, Washington University School of Medicine, St Louis, MO, USA
| | - Zhude Tu
- 1 Department of Radiology, Washington University School of Medicine, St Louis, MO, USA
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32
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Liu C, Liu H, Jin H, Yue X, Luo Z, Tu Z. Cholinergic imbalance in lumbar spinal cord of a rat model of multiple sclerosis. J Neuroimmunol 2018; 318:29-35. [PMID: 29397207 DOI: 10.1016/j.jneuroim.2018.01.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/16/2018] [Accepted: 01/22/2018] [Indexed: 12/01/2022]
Abstract
Cholinergic dysfunction in the central nervous system is an important characteristic of multiple sclerosis and experimental autoimmune encephalomyelitis (EAE). By using a rat EAE model, upregulation of vesicular acetylcholine transporter (VAChT) level in the EAE rat lumbar spinal cord was detected by western blot and immunostaining, and was associated with lymphocyte filtration and glial activation. Ex vivo and in vitro autoradiography studies with [18F]VAT, a VAChT-specific radioligand, also revealed increased tracer uptake in EAE rat lumbar spinal cord compared with shams. These studies on VAChT expression suggest central cholinergic imbalance during EAE progression.
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Affiliation(s)
- Chunling Liu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hui Liu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hongjun Jin
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Xuyi Yue
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zonghua Luo
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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33
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Narayanaswami V, Dahl K, Bernard-Gauthier V, Josephson L, Cumming P, Vasdev N. Emerging PET Radiotracers and Targets for Imaging of Neuroinflammation in Neurodegenerative Diseases: Outlook Beyond TSPO. Mol Imaging 2018; 17:1536012118792317. [PMID: 30203712 PMCID: PMC6134492 DOI: 10.1177/1536012118792317] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Revised: 05/31/2018] [Accepted: 07/09/2018] [Indexed: 11/16/2022] Open
Abstract
The dynamic and multicellular processes of neuroinflammation are mediated by the nonneuronal cells of the central nervous system, which include astrocytes and the brain's resident macrophages, microglia. Although initiation of an inflammatory response may be beneficial in response to injury of the nervous system, chronic or maladaptive neuroinflammation can have harmful outcomes in many neurological diseases. An acute neuroinflammatory response is protective when activated neuroglia facilitate tissue repair by releasing anti-inflammatory cytokines and neurotrophic factors. On the other hand, chronic neuroglial activation is a major pathological mechanism in neurodegenerative diseases, likely contributing to neuronal dysfunction, injury, and disease progression. Therefore, the development of specific and sensitive probes for positron emission tomography (PET) studies of neuroinflammation is attracting immense scientific and clinical interest. An early phase of this research emphasized PET studies of the prototypical imaging biomarker of glial activation, translocator protein-18 kDa (TSPO), which presents difficulties for quantitation and lacks absolute cellular specificity. Many alternate molecular targets present themselves for PET imaging of neuroinflammation in vivo, including enzymes, intracellular signaling molecules as well as ionotropic, G-protein coupled, and immunoglobulin receptors. We now review the lead structures in radiotracer development for PET studies of neuroinflammation targets for neurodegenerative diseases extending beyond TSPO, including glycogen synthase kinase 3, monoamine oxidase-B, reactive oxygen species, imidazoline-2 binding sites, cyclooxygenase, the phospholipase A2/arachidonic acid pathway, sphingosine-1-phosphate receptor-1, cannabinoid-2 receptor, the chemokine receptor CX3CR1, purinergic receptors: P2X7 and P2Y12, the receptor for advanced glycation end products, Mer tyrosine kinase, and triggering receptor expressed on myeloid cells-1. We provide a brief overview of the cellular expression and function of these targets, noting their selectivity for astrocytes and/or microglia, and highlight the classes of PET radiotracers that have been investigated in early-stage preclinical or clinical research studies of neuroinflammation.
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Affiliation(s)
- Vidya Narayanaswami
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, MA, USA
- Azrieli Centre for Neuro-Radiochemistry, Research Imaging Centre, Centre for Addiction and Mental Health & Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Kenneth Dahl
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, MA, USA
- Azrieli Centre for Neuro-Radiochemistry, Research Imaging Centre, Centre for Addiction and Mental Health & Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Vadim Bernard-Gauthier
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Lee Josephson
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Paul Cumming
- School of Psychology and Counselling and IHBI, Queensland University of Technology, Brisbane, Queensland, Australia
- QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Neil Vasdev
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, MA, USA
- Azrieli Centre for Neuro-Radiochemistry, Research Imaging Centre, Centre for Addiction and Mental Health & Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
- Department of Radiology, Harvard Medical School, Boston, MA, USA
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Mahajan KR, Ontaneda D. The Role of Advanced Magnetic Resonance Imaging Techniques in Multiple Sclerosis Clinical Trials. Neurotherapeutics 2017; 14:905-923. [PMID: 28770481 PMCID: PMC5722766 DOI: 10.1007/s13311-017-0561-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Magnetic resonance imaging has been crucial in the development of anti-inflammatory disease-modifying treatments. The current landscape of multiple sclerosis clinical trials is currently expanding to include testing not only of anti-inflammatory agents, but also neuroprotective, remyelinating, neuromodulating, and restorative therapies. This is especially true of therapies targeting progressive forms of the disease where neurodegeneration is a prominent feature. Imaging techniques of the brain and spinal cord have rapidly evolved in the last decade to permit in vivo characterization of tissue microstructural changes, connectivity, metabolic changes, neuronal loss, glial activity, and demyelination. Advanced magnetic resonance imaging techniques hold significant promise for accelerating the development of different treatment modalities targeting a variety of pathways in MS.
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Affiliation(s)
- Kedar R Mahajan
- Mellen Center for Multiple Sclerosis Treatment and Research, Cleveland Clinic, 9500 Euclid Avenue, U-10, Cleveland, OH, 44195, USA
| | - Daniel Ontaneda
- Mellen Center for Multiple Sclerosis Treatment and Research, Cleveland Clinic, 9500 Euclid Avenue, U-10, Cleveland, OH, 44195, USA.
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35
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Han J, Liu H, Liu C, Jin H, Perlmutter JS, Egan TM, Tu Z. Pharmacologic characterizations of a P2X7 receptor-specific radioligand, [11C]GSK1482160 for neuroinflammatory response. Nucl Med Commun 2017; 38:372-382. [PMID: 28338530 PMCID: PMC5401628 DOI: 10.1097/mnm.0000000000000660] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The P2X7 receptor (P2X7R) is a key regulatory element in the neuroinflammatory cascade that provides a promising target for imaging neuroinflammation. GSK1482160, a P2X7R modulator with nanomolar binding affinity and high selectivity, has been successfully radiolabeled and utilized for imaging P2X7 levels in a mouse model of lipopolysaccharide-induced systemic inflammation. In the current study, we further characterized its binding profile and determined whether [C]GSK1482160 can detect changes in P2X7R expression in a rodent model of multiple sclerosis. METHODS [C]GSK1482160 was synthesized with high specific activity and high radiochemical purity. Radioligand saturation and competition binding assays were performed for [C]GSK1482160 using HEK293-hP2X7R living cells. Micro-PET studies were carried out in nonhuman primates. In vitro autoradiography and immunohistochemistry studies were then carried out to evaluate tracer uptake and P2X7 expression in experimental autoimmune encephalomyelitis (EAE) rat lumbar spinal cord at EAE-peak and EAE-remitting stages compared with sham rats. RESULTS [C]GSK1482160 binds to HEK293-hP2X7R living cells with high binding affinity (Kd=5.09±0.98 nmol/l, Ki=2.63±0.6 nmol/l). Micro-PET studies showed high tracer retention and a homogeneous distribution in the brain of nonhuman primates. In the EAE rat model, tracer uptake of [C]GSK1482160 in rat lumbar spinal cord was the highest at the EAE-peak stage (277.74±79.74 PSL/mm), followed by the EAE-remitting stage(149.00±54.14 PSL/mm) and sham (66.37±1.48 PSL/mm). The tracer uptake correlated strongly with P2X7-positive cell counts, activated microglia numbers, and disease severity. CONCLUSION We conclude that [C]GSK1482160 has the potential for application in monitoring neuroinflammation.
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Affiliation(s)
- Junbin Han
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hui Liu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Chunling Liu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hongjun Jin
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Joel S. Perlmutter
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Department of Neurology, Neuroscience, Physical Therapy and Occupational Therapy, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Terrance M. Egan
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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36
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Rosenberg AJ, Liu H, Jin H, Yue X, Riley S, Brown SJ, Tu Z. Design, Synthesis, and In Vitro and In Vivo Evaluation of an (18)F-Labeled Sphingosine 1-Phosphate Receptor 1 (S1P1) PET Tracer. J Med Chem 2016; 59:6201-20. [PMID: 27280499 PMCID: PMC5091660 DOI: 10.1021/acs.jmedchem.6b00390] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Sphingosine 1-phosphate receptor 1 (S1P1) plays a pivotal signaling role in inflammatory response; because S1P1 modulation has been identified as a therapeutic target for various diseases, a PET tracer for S1P1 would be a useful tool. Fourteen fluorine-containing analogues of S1P ligands were synthesized and their in vitro binding potency measured; four had high potency and selectivity for S1P1 (S1P1 IC50 < 10 nM, >100-fold selectivity for S1P1 over S1P2 and S1P3). The most potent ligand, 28c (IC50 = 2.63 nM for S1P1) was (18)F-labeled and evaluated in a mouse model of LPS-induced acute liver injury to determine its S1P1-binding specificity. The results from biodistribution, autoradiography, and microPET imaging showed higher [(18)F]28c accumulation in the liver of LPS-treated mice than controls. Increased expression of S1P1 in the LPS model was confirmed by immunohistochemical analysis (IHC). These data suggest that [(18)F]28c is a S1P1 PET tracer with high potential for imaging S1P1 in vivo.
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Affiliation(s)
- Adam J. Rosenberg
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, St. Louis, Missouri 63110, United States
| | - Hui Liu
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, St. Louis, Missouri 63110, United States
| | - Hongjun Jin
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, St. Louis, Missouri 63110, United States
| | - Xuyi Yue
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, St. Louis, Missouri 63110, United States
| | - Sean Riley
- The Scripps Research Institute Molecular Screening Center, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Steven J. Brown
- The Scripps Research Institute Molecular Screening Center, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, St. Louis, Missouri 63110, United States
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