1
|
Wang J, Li Y, El Fakhri G. Advances and Insights in Positron Emission Tomography Tracers for Metabotropic Glutamate Receptor 4 Imaging. J Med Chem 2024; 67:10517-10529. [PMID: 38924702 DOI: 10.1021/acs.jmedchem.3c02431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
Positron emission tomography (PET) imaging employs positron-emitting radioisotopes to visualize biological processes in living subjects with high sensitivity and quantitative accuracy. As the most translational molecular imaging modality, PET can detect and image a wide range of radiotracers with minimal or no modification to parent drugs or targeting molecules. This Perspective provides a comprehensive analysis of developing PET radioligands using allosteric modulators for the metabotropic glutamate receptor subtype 4 (mGluR4) as a therapeutic target for neurological disorders. We focus on the selection of lead compounds from various chemotypes of mGluR4 positive allosteric modulators (PAMs) and discuss the challenges and systematic characterization required in developing brain-penetrant PET tracers specific for mGluR4. Through this analysis, we offer insights into the development and evaluation of PET ligands. Our review concludes that further research and development in this field hold great promise for discovering effective treatments for neurological disorders.
Collapse
Affiliation(s)
- Junfeng Wang
- Gordon Center for Medical Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Charlestown, Massachusetts 02119, United States
| | - Yingbo Li
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Georges El Fakhri
- PET Center, School of Medicine, Yale University, New Haven, Connecticut 06520, United States
| |
Collapse
|
2
|
Zhao Q, Telu S, Jana S, Morse CL, Pike VW. Isotopologues of potassium 2,2,2-trifluoroethoxide for applications in positron emission tomography and beyond. Nat Commun 2024; 15:5798. [PMID: 38987549 PMCID: PMC11237122 DOI: 10.1038/s41467-024-49975-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 06/26/2024] [Indexed: 07/12/2024] Open
Abstract
The 2,2,2-trifluoroethoxy group increasingly features in drugs and potential tracers for biomedical imaging with positron emission tomography (PET). Herein, we describe a rapid and transition metal-free conversion of fluoroform with paraformaldehyde into highly reactive potassium 2,2,2-trifluoroethoxide (CF3CH2OK) and demonstrate robust applications of this synthon in one-pot, two-stage 2,2,2-trifluoroethoxylations of both aromatic and aliphatic precursors. Moreover, we show that these transformations translate easily to fluoroform that has been labeled with either carbon-11 (t1/2 = 20.4 min) or fluorine-18 (t1/2 = 109.8 min), so allowing the appendage of complex molecules with a no-carrier-added 11C- or 18F- 2,2,2-trifluoroethoxy group. This provides scope to create candidate PET tracers with radioactive and metabolically stable 2,2,2-trifluoroethoxy moieties. We also exemplify syntheses of isotopologues of potassium 2,2,2-trifluoroethoxide and show their utility for stable isotopic labeling which can be of further benefit for drug discovery and development.
Collapse
Affiliation(s)
- Qunchao Zhao
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, 10 Center Drive, Bethesda, MD, 20892-1003, USA
| | - Sanjay Telu
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, 10 Center Drive, Bethesda, MD, 20892-1003, USA.
| | - Susovan Jana
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, 10 Center Drive, Bethesda, MD, 20892-1003, USA
| | - Cheryl L Morse
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, 10 Center Drive, Bethesda, MD, 20892-1003, USA
| | - Victor W Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, 10 Center Drive, Bethesda, MD, 20892-1003, USA.
| |
Collapse
|
3
|
Huang CH, Khan P, Xu S, Cohen J, Georgakis GV, Turkman N. Development of a Radiolabeled Cyclin-Dependent Kinases 4 and 6 (CDK4/6) Inhibitor for Brain and Cancer PET Imaging. Int J Mol Sci 2024; 25:6870. [PMID: 38999983 PMCID: PMC11241330 DOI: 10.3390/ijms25136870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 06/18/2024] [Accepted: 06/19/2024] [Indexed: 07/14/2024] Open
Abstract
The synthesis, biochemical evaluation and radiosynthesis of a cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitor and radioligand was performed. NT431, a newly synthesized 4-fluorobenzyl-abemaciclib, exhibited high potency to CDK4/6 and against four cancer cell lines with IC50 similar to that of the parent abemaciclib. We performed a two-step one-pot radiosynthesis to produce [18F]NT431 with good radiochemical yield (9.6 ± 3%, n = 3, decay uncorrected), high radiochemical purity (>95%), and high molar activity (>370 GBq/µmol (>10.0 Ci/µmol). In vitro autoradiography confirmed the specific binding of [18F]NT431 to CDK4/6 in brain tissues. Dynamic PET imaging supports that both [18F]NT431 and the parent abemaciclib crossed the BBB albeit with modest brain uptake. Therefore, we conclude that it is unlikely that NT431 or abemaciclib (FDA approved drug) can accumulate in the brain in sufficient concentrations to be potentially effective against breast cancer brain metastases or brain cancers. However, despite the modest BBB penetration, [18F]NT431 represents an important step towards the development and evaluation of a new generation of CDK4/6 inhibitors with superior BBB penetration for the treatment and visualization of CDK4/6 positive tumors in the CNS. Also, [18F]NT431 may have potential application in peripheral tumors such as breast cancer and other CDK4/6 positive tumors.
Collapse
Affiliation(s)
- Chun-Han Huang
- Stony Brook Cancer Center, Stony Brook, Long Island, NY 11794, USA
- Department of Radiology, School of Medicine, Stony Brook University, Long Island, NY 11794, USA
- Department of Biomedical Engineering, Stony Brook University, Long Island, NY 11794, USA
| | - Palwasha Khan
- Stony Brook Cancer Center, Stony Brook, Long Island, NY 11794, USA
- Department of Radiology, School of Medicine, Stony Brook University, Long Island, NY 11794, USA
| | - Sulan Xu
- Stony Brook Cancer Center, Stony Brook, Long Island, NY 11794, USA
- Department of Radiology, School of Medicine, Stony Brook University, Long Island, NY 11794, USA
| | - Jules Cohen
- Stony Brook Cancer Center, Stony Brook, Long Island, NY 11794, USA
- Department of Medicine, School of Medicine, Stony Brook University, Long Island, NY 11794, USA
| | - Georgios V Georgakis
- Stony Brook Cancer Center, Stony Brook, Long Island, NY 11794, USA
- Department of Surgery, School of Medicine, Stony Brook University, Long Island, NY 11794, USA
| | - Nashaat Turkman
- Stony Brook Cancer Center, Stony Brook, Long Island, NY 11794, USA
- Department of Radiology, School of Medicine, Stony Brook University, Long Island, NY 11794, USA
- Department of Biomedical Engineering, Stony Brook University, Long Island, NY 11794, USA
| |
Collapse
|
4
|
Wu J, Mao M, Yang J, Li K, Deng P, Zhong J, Wu X, Cheng Y. Development of an 18F-labeled azobenzothiazole tracer for α-synuclein aggregates in the brain. Org Biomol Chem 2024; 22:4550-4558. [PMID: 38768281 DOI: 10.1039/d4ob00492b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Nuclear imaging of aggregated α-synuclein pathology is an urgent clinical need for Parkinson's disease, yet promising tracers for brain α-synuclein aggregates are still rare. In this work, a class of compact benzothiazole derivatives was synthesized and evaluated for α-synuclein aggregates. Among them, azobenzothiazoles exhibited specific and selective detection of α-synuclein aggregates under physiological conditions. Fluoro-pegylated azobenzothiazole NN-F further demonstrated high-affinity binding to α-synuclein aggregates and efficient 18F-radiolabeling via nucleophilic displacement of a tosyl precursor. [18F]NN-F was stable in plasma in vitro and showed efficient brain uptake with little defluorination in vivo.
Collapse
Affiliation(s)
- Jiajun Wu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Meiting Mao
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Jie Yang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Kexin Li
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Pengxin Deng
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Jing Zhong
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| | - Xiaoai Wu
- Department of Nuclear Medicine, Laboratory of Clinical Nuclear Medicine, West China Hospital, Sichuan University, Chengdu 610041, China.
| | - Yan Cheng
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
| |
Collapse
|
5
|
Dickmann CGF, Milicevic Sephton S, Barker RA, Aigbirhio FI. PET Ligands for Imaging Mutant Huntingtin Aggregates: A Case Study in Non-For-Profit Scientific Management. Chembiochem 2024; 25:e202400152. [PMID: 38695673 DOI: 10.1002/cbic.202400152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/02/2024] [Indexed: 06/13/2024]
Abstract
Positron emission tomography imaging of misfolded proteins with high-affinity and selective radioligands has played a vital role in expanding our knowledge of neurodegenerative diseases such as Parkinson's and Alzheimer's disease. The pathogenesis of Huntington's disease, a CAG trinucleotide repeat disorder, is similarly linked to the presence of protein fibrils formed from mutant huntingtin (mHTT) protein. Development of mHTT fibril-specific radioligands has been limited by the lack of structural knowledge around mHTT and a dearth of available hit compounds for medicinal chemistry refinement. Over the past decade, the CHDI Foundation, a non-for-profit scientific management organisation has orchestrated a large-scale screen of small molecules to identify high affinity ligands of mHTT, with lead compounds now reaching clinical maturity. Here we describe the mHTT radioligands developed to date and opportunities for further improvement of this radiotracer class.
Collapse
Affiliation(s)
- Catherine G F Dickmann
- Molecular Imaging Chemistry Laboratory, Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
| | - Selena Milicevic Sephton
- Molecular Imaging Chemistry Laboratory, Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
| | - Roger A Barker
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
| | - Franklin I Aigbirhio
- Molecular Imaging Chemistry Laboratory, Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
6
|
Santos L, Moreira JN, Abrunhosa A, Gomes C. Brain metastasis: An insight into novel molecular targets for theranostic approaches. Crit Rev Oncol Hematol 2024; 198:104377. [PMID: 38710296 DOI: 10.1016/j.critrevonc.2024.104377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 04/11/2024] [Accepted: 04/25/2024] [Indexed: 05/08/2024] Open
Abstract
Brain metastases (BrM) are common malignant lesions in the central nervous system, and pose a significant threat in advanced-stage malignancies due to delayed diagnosis and limited therapeutic options. Their distinct genomic profiles underscore the need for molecular profiling to tailor effective treatments. Recent advances in cancer biology have uncovered molecular drivers underlying tumor initiation, progression, and metastasis. This, coupled with the advances in molecular imaging technology and radiotracer synthesis, has paved the way for the development of innovative radiopharmaceuticals with enhanced specificity and affinity for BrM specific targets. Despite the challenges posed by the blood-brain barrier to effective drug delivery, several radiolabeled compounds have shown promise in detecting and targeting BrM. This manuscript provides an overview of the recent advances in molecular biomarkers used in nuclear imaging and targeted radionuclide therapy in both clinical and preclinical settings. Additionally, it explores potential theranostic applications addressing the unique challenges posed by BrM.
Collapse
Affiliation(s)
- Liliana Santos
- Institute for Nuclear Sciences Applied to Health (ICNAS) and Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), University of Coimbra, Coimbra 3000-548, Portugal; Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra 3000-548, Portugal
| | - João Nuno Moreira
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra 3004-504, Portugal; Center for Innovative Biomedicine and Biotechnology Consortium (CIBB), University of Coimbra, Coimbra 3000-548, Portugal
| | - Antero Abrunhosa
- Institute for Nuclear Sciences Applied to Health (ICNAS) and Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), University of Coimbra, Coimbra 3000-548, Portugal
| | - Célia Gomes
- Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra 3000-548, Portugal; Center for Innovative Biomedicine and Biotechnology Consortium (CIBB), University of Coimbra, Coimbra 3000-548, Portugal; Clinical Academic Center of Coimbra (CACC), Coimbra 3000-075, Portugal.
| |
Collapse
|
7
|
Sun Y, Rodríguez-Rangel S, Zhang LL, Sánchez-Rodríguez JE, Brugarolas P. Chemical and biophysical characterization of novel potassium channel blocker 3-fluoro-5-methylpyridin-4-amine. Sci Rep 2024; 14:11105. [PMID: 38750155 PMCID: PMC11096398 DOI: 10.1038/s41598-024-61465-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Accepted: 05/06/2024] [Indexed: 05/18/2024] Open
Abstract
4-aminopyridine (4AP) is a potassium (K+) channel blocker used clinically to improve walking in people with multiple sclerosis (MS). 4AP binds to exposed K+ channels in demyelinated axons, reducing the leakage of intracellular K+ and enhancing impulse conduction. Multiple derivatives of 4AP capable of blocking K+ channels have been reported including three radiolabeled with positron emitting isotopes for imaging demyelinated lesions using positron emission tomography (PET). However, there remains a demand for novel molecules with suitable physicochemical properties and binding affinity that can potentially be radiolabeled and used as PET radiotracers. In this study, we introduce 3-fluoro-5-methylpyridin-4-amine (5Me3F4AP) as a novel trisubstituted K+ channel blocker with potential application in PET. 5Me3F4AP has comparable potency to 4AP and the PET tracer 3-fluoro-4-aminopyridine (3F4AP). Compared to 3F4AP, 5Me3F4AP exhibits comparable basicity (pKa = 7.46 ± 0.01 vs. 7.37 ± 0.07, P-value = 0.08), greater lipophilicity (logD = 0.664 ± 0.005 vs. 0.414 ± 0.002, P-value < 0.0001) and higher permeability to an artificial brain membrane (Pe = 88.1 ± 18.3 vs. 31.1 ± 2.9 nm/s, P-value = 0.03). 5Me3F4AP is also more stable towards oxidation in vitro by the cytochrome P450 enzyme CYP2E1 (IC50 = 36.2 ± 2.5 vs. 15.4 ± 5.1, P-value = 0.0003); the enzyme responsible for the metabolism of 4AP and 3F4AP. Taken together, 5Me3F4AP has promising properties as a candidate for PET imaging warranting additional investigation.
Collapse
Affiliation(s)
- Yang Sun
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | | | - Lauren L Zhang
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | | | - Pedro Brugarolas
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA.
| |
Collapse
|
8
|
Emvalomenos GM, Kang JWM, Jupp B, Mychasiuk R, Keay KA, Henderson LA. Recent developments and challenges in positron emission tomography imaging of gliosis in chronic neuropathic pain. Pain 2024:00006396-990000000-00597. [PMID: 38713812 DOI: 10.1097/j.pain.0000000000003247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 03/05/2024] [Indexed: 05/09/2024]
Abstract
ABSTRACT Understanding the mechanisms that underpin the transition from acute to chronic pain is critical for the development of more effective and targeted treatments. There is growing interest in the contribution of glial cells to this process, with cross-sectional preclinical studies demonstrating specific changes in these cell types capturing targeted timepoints from the acute phase and the chronic phase. In vivo longitudinal assessment of the development and evolution of these changes in experimental animals and humans has presented a significant challenge. Recent technological advances in preclinical and clinical positron emission tomography, including the development of specific radiotracers for gliosis, offer great promise for the field. These advances now permit tracking of glial changes over time and provide the ability to relate these changes to pain-relevant symptomology, comorbid psychiatric conditions, and treatment outcomes at both a group and an individual level. In this article, we summarize evidence for gliosis in the transition from acute to chronic pain and provide an overview of the specific radiotracers available to measure this process, highlighting their potential, particularly when combined with ex vivo/in vitro techniques, to understand the pathophysiology of chronic neuropathic pain. These complementary investigations can be used to bridge the existing gap in the field concerning the contribution of gliosis to neuropathic pain and identify potential targets for interventions.
Collapse
Affiliation(s)
- Gaelle M Emvalomenos
- School of Medical Sciences [Neuroscience], and the Brain and Mind Centre, The University of Sydney, Sydney, Australia
| | - James W M Kang
- School of Medical Sciences [Neuroscience], and the Brain and Mind Centre, The University of Sydney, Sydney, Australia
| | - Bianca Jupp
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Australia
| | - Richelle Mychasiuk
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Australia
| | - Kevin A Keay
- School of Medical Sciences [Neuroscience], and the Brain and Mind Centre, The University of Sydney, Sydney, Australia
| | - Luke A Henderson
- School of Medical Sciences [Neuroscience], and the Brain and Mind Centre, The University of Sydney, Sydney, Australia
| |
Collapse
|
9
|
Jiang M, Tang S, Jenkins MD, Lee AC, Kenou B, Knoer C, Montero Santamaria J, Wu S, Liow JS, Zoghbi SS, Zanotti-Fregonara P, Innis RB, Telu S, Pike VW. Robust Quantification of Phosphodiesterase-4D in Monkey Brain with PET and 11C-Labeled Radioligands That Avoid Radiometabolite Contamination. J Nucl Med 2024; 65:788-793. [PMID: 38423785 PMCID: PMC11064827 DOI: 10.2967/jnumed.123.266750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 01/05/2024] [Indexed: 03/02/2024] Open
Abstract
Phosphodiesterase-4D (PDE4D) has emerged as a significant target for treating neuropsychiatric disorders, but no PET radioligand currently exists for robustly quantifying human brain PDE4D to assist biomedical research and drug discovery. A prior candidate PDE4D PET radioligand, namely [11C]T1650, failed in humans because of poor time stability of brain PDE4D-specific signal (indexed by total volume of distribution), likely due to radiometabolites accumulating in brain. Its nitro group was considered to be a source of the brain radiometabolites. Methods: We selected 5 high-affinity and selective PDE4D inhibitors, absent of a nitro group, from our prior structure-activity relationship study for evaluation as PET radioligands. Results: All 5 radioligands were labeled with 11C (half-time, 20.4 min) in useful yields and with high molar activity. All displayed sizable PDE4D-specific signals in rhesus monkey brain. Notably, [11C]JMJ-81 and [11C]JMJ-129 exhibited excellent time stability of signal (total volume of distribution). Furthermore, as an example, [11C]JMJ-81 was found to be free of radiometabolites in ex vivo monkey brain, affirming that this radioligand can provide robust quantification of brain PDE4D with PET. Conclusion: Given their high similarity in structures and metabolic profiles, both [11C]JMJ-81 and [11C]JMJ-129 warrant further evaluation in human subjects. [11C]JMJ-129 shows a higher PDE4D specific-to-nonspecific binding ratio and will be the first to be evaluated.
Collapse
Affiliation(s)
- Meijuan Jiang
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Shiyu Tang
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Madeline D Jenkins
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Adrian C Lee
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Bruny Kenou
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Carson Knoer
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Jose Montero Santamaria
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Shawn Wu
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Jeih-San Liow
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Sami S Zoghbi
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Paolo Zanotti-Fregonara
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Robert B Innis
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Sanjay Telu
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Victor W Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
10
|
Ramos-Torres K, Sun Y, Takahashi K, Zhou YP, Brugarolas P. Common anesthetic used in preclinical PET imaging inhibits metabolism of the PET tracer [ 18F]3F4AP. J Neurochem 2024. [PMID: 38690718 DOI: 10.1111/jnc.16118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 04/11/2024] [Accepted: 04/11/2024] [Indexed: 05/02/2024]
Abstract
Positron emission tomography (PET) imaging studies in laboratory animals are almost always performed under isoflurane anesthesia to ensure that the subject stays still during the image acquisition. Isoflurane is effective, safe, and easy to use, and it is generally assumed to not have an impact on the imaging results. Motivated by marked differences observed in the brain uptake and metabolism of the PET tracer 3-[18F]fluoro-4-aminopyridine [(18F]3F4AP) between human and nonhuman primate studies, this study investigates the possible effect of isoflurane on this process. Mice received [18F]3F4AP injection while awake or under anesthesia and the tracer brain uptake and metabolism was compared between groups. A separate group of mice received the known cytochrome P450 2E1 inhibitor disulfiram prior to tracer administration. Isoflurane was found to largely abolish tracer metabolism in mice (74.8 ± 1.6 vs. 17.7 ± 1.7% plasma parent fraction, % PF) resulting in a 4.0-fold higher brain uptake in anesthetized mice at 35 min post-radiotracer administration. Similar to anesthetized mice, animals that received disulfiram showed reduced metabolism (50.0 ± 6.9% PF) and a 2.2-fold higher brain signal than control mice. The higher brain uptake and lower metabolism of [18F]3F4AP observed in anesthetized mice compared to awake mice are attributed to isoflurane's interference in the CYP2E1-mediated breakdown of the tracer, which was confirmed by reproducing the effect upon treatment with the known CYP2E1 inhibitor disulfiram. These findings underscore the critical need to examine the effect of isoflurane in PET imaging studies before translating tracers to humans that will be scanned without anesthesia.
Collapse
Affiliation(s)
- Karla Ramos-Torres
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Yang Sun
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Kazue Takahashi
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Yu-Peng Zhou
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Pedro Brugarolas
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
11
|
Pees A, Tong J, Birudaraju S, Munot YS, Liang SH, Saturnino Guarino D, Mach RH, Mathis CA, Vasdev N. Development of Pyridothiophene Compounds for PET Imaging of α-Synuclein. Chemistry 2024; 30:e202303921. [PMID: 38354298 DOI: 10.1002/chem.202303921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/29/2024] [Accepted: 02/14/2024] [Indexed: 02/16/2024]
Abstract
Aggregated α-synuclein (α-syn) protein is a pathological hallmark of Parkinson's disease (PD) and Lewy body dementia (LBD). Development of positron emission tomography (PET) radiotracers to image α-syn aggregates has been a longstanding goal. This work explores the suitability of a pyridothiophene scaffold for α-syn PET radiotracers, where 47 derivatives of a potent pyridothiophene (asyn-44; Kd=1.85 nM) were synthesized and screened against [3H]asyn-44 in competitive binding assays using post-mortem PD brain homogenates. Equilibrium inhibition constant (Ki) values of the most potent compounds were determined, of which three had Ki's in the lower nanomolar range (12-15 nM). An autoradiography study confirmed that [3H]asyn-44 is promising for imaging brain sections from multiple system atrophy and PD donors. Fluorine-18 labelled asyn-44 was synthesized in 6±2 % radiochemical yield (decay-corrected, n=5) with a molar activity of 263±121 GBq/μmol. Preliminary PET imaging of [18F]asyn-44 in rats showed high initial brain uptake (>1.5 standardized uptake value (SUV)), moderate washout (~0.4 SUV at 60 min), and low variability. Radiometabolite analysis showed 60-80 % parent tracer in the brain after 30 and 60 mins. While [18F]asyn-44 displayed good in vitro properties and acceptable brain uptake, troublesome radiometabolites precluded further PET imaging studies. The synthesis and in vitro evaluation of additional pyridothiophene derivatives are underway, with the goal of attaining improved affinity and metabolic stability.
Collapse
Affiliation(s)
- Anna Pees
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, ON M5T 1R8, Canada
| | - Junchao Tong
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, ON M5T 1R8, Canada
| | | | | | - Steven H Liang
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, United States
| | - Dinahlee Saturnino Guarino
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1012, 231 S. 34th Street, Philadelphia, Pennsylvania, 19104-6323, United States
| | - Robert H Mach
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1012, 231 S. 34th Street, Philadelphia, Pennsylvania, 19104-6323, United States
| | - Chester A Mathis
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213, United States
| | - Neil Vasdev
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON M5T-1R8, Canada
| |
Collapse
|
12
|
Pan MT, Zhang H, Li XJ, Guo XY. Genetically modified non-human primate models for research on neurodegenerative diseases. Zool Res 2024; 45:263-274. [PMID: 38287907 PMCID: PMC11017080 DOI: 10.24272/j.issn.2095-8137.2023.197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Accepted: 01/25/2024] [Indexed: 01/31/2024] Open
Abstract
Neurodegenerative diseases (NDs) are a group of debilitating neurological disorders that primarily affect elderly populations and include Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS). Currently, there are no therapies available that can delay, stop, or reverse the pathological progression of NDs in clinical settings. As the population ages, NDs are imposing a huge burden on public health systems and affected families. Animal models are important tools for preclinical investigations to understand disease pathogenesis and test potential treatments. While numerous rodent models of NDs have been developed to enhance our understanding of disease mechanisms, the limited success of translating findings from animal models to clinical practice suggests that there is still a need to bridge this translation gap. Old World non-human primates (NHPs), such as rhesus, cynomolgus, and vervet monkeys, are phylogenetically, physiologically, biochemically, and behaviorally most relevant to humans. This is particularly evident in the similarity of the structure and function of their central nervous systems, rendering such species uniquely valuable for neuroscience research. Recently, the development of several genetically modified NHP models of NDs has successfully recapitulated key pathologies and revealed novel mechanisms. This review focuses on the efficacy of NHPs in modeling NDs and the novel pathological insights gained, as well as the challenges associated with the generation of such models and the complexities involved in their subsequent analysis.
Collapse
Affiliation(s)
- Ming-Tian Pan
- Guangdong Key Laboratory of Non-human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong 510632, China
| | - Han Zhang
- Guangdong Key Laboratory of Non-human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong 510632, China
| | - Xiao-Jiang Li
- Guangdong Key Laboratory of Non-human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong 510632, China
| | - Xiang-Yu Guo
- Guangdong Key Laboratory of Non-human Primate Research, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong 510632, China. E-mail:
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
Nerella SG, Telu S, Liow JS, Jenkins MD, Zoghbi SS, Gomez JL, Michaelides M, Eldridge MAG, Richmond BJ, Innis RB, Pike VW. Synthesis and preclinical evaluation of [ 11C]uPSEM792 for PSAM 4-GlyR based chemogenetics. Sci Rep 2024; 14:1886. [PMID: 38253691 PMCID: PMC10803328 DOI: 10.1038/s41598-024-51307-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 01/01/2024] [Indexed: 01/24/2024] Open
Abstract
Chemogenetic tools are designed to control neuronal signaling. These tools have the potential to contribute to the understanding of neuropsychiatric disorders and to the development of new treatments. One such chemogenetic technology comprises modified Pharmacologically Selective Actuator Modules (PSAMs) paired with Pharmacologically Selective Effector Molecules (PSEMs). PSAMs are receptors with ligand-binding domains that have been modified to interact only with a specific small-molecule agonist, designated a PSEM. PSAM4 is a triple mutant PSAM derived from the α7 nicotinic receptor (α7L131G,Q139L,Y217F). Although having no constitutive activity as a ligand-gated ion channel, PSAM4 has been coupled to the serotonin 5-HT3 receptor (5-HT3R) and to the glycine receptor (GlyR). Treatment with the partner PSEM to activate PSAM4-5-HT3 or PSAM4-GlyR, causes neuronal activation or silencing, respectively. A suitably designed radioligand may enable selective visualization of the expression and location of PSAMs with positron emission tomography (PET). Here, we evaluated uPSEM792, an ultrapotent PSEM for PSAM4-GlyR, as a possible lead for PET radioligand development. We labeled uPSEM792 with the positron-emitter, carbon-11 (t1/2 = 20.4 min), in high radiochemical yield by treating a protected precursor with [11C]iodomethane followed by base deprotection. PET experiments with [11C]uPSEM792 in rodents and in a monkey transduced with PSAM4-GlyR showed low peak radioactivity uptake in brain. This low uptake was probably due to high polarity of the radioligand, as evidenced by physicochemical measurements, and to the vulnerability of the radioligand to efflux transport at the blood-brain barrier. These findings can inform the design of a more effective PSAM4 based PET radioligand, based on the uPSEM792 chemotype.
Collapse
Affiliation(s)
- Sridhar Goud Nerella
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Sanjay Telu
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.
| | - Jeih-San Liow
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Madeline D Jenkins
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Sami S Zoghbi
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Juan L Gomez
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - Michael Michaelides
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - Mark A G Eldridge
- Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Barry J Richmond
- Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Robert B Innis
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Victor W Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.
| |
Collapse
|
15
|
Xu Y, Xu Y, Biby S, Kaur B, Liu Y, Bagdasarian FA, Wey HY, Tanzi R, Zhang C, Wang C, Zhang S. Design and Discovery of Novel NLRP3 Inhibitors and PET Imaging Radiotracers Based on a 1,2,3-Triazole-Bearing Scaffold. J Med Chem 2024; 67:555-571. [PMID: 38150705 PMCID: PMC11002996 DOI: 10.1021/acs.jmedchem.3c01782] [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: 12/29/2023]
Abstract
The NOD-like receptor (NLR) family pyrin-domain-containing 3 (NLRP3) inflammasome, an essential component of the innate immune system, has been emerging as a viable drug target and a potential biomarker for human diseases. In our efforts to develop novel small molecule NLRP3 inhibitors, a 1-(5-chloro-2-methoxybenzyl)-4-phenyl-1H-1,2,3-triazole scaffold was designed via a rational approach based on our previous leads. Structure-activity relationship studies and biophysical studies identified a new lead compound 8 as a potent (IC50: 0.55 ± 0.16 μM), selective, and direct NLRP3 inhibitor. Positron emission tomography (PET) imaging studies of [11C]8 demonstrated its rapid and high brain uptake as well as fast washout in mice and rhesus macaque. Notably, plasma kinetic analysis of this radiotracer from the PET/magnetic resonance imaging studies in rhesus macaque suggested radiometabolic stability. Collectively, our data not only encourage further studies of this lead compound but also warrant further optimization to generate additional novel NLRP3 inhibitors and suitable central nervous system PET radioligands with translational promise.
Collapse
Affiliation(s)
- Yiming Xu
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Yulong Xu
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Savannah Biby
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Baljit Kaur
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Yan Liu
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Frederick Andrew Bagdasarian
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Hsiao-Ying Wey
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Rudolph Tanzi
- Genetics and Aging Research Unit, McCane Center for Brain Health, Mass General Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Can Zhang
- Genetics and Aging Research Unit, McCane Center for Brain Health, Mass General Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Changning Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Shijun Zhang
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| |
Collapse
|
16
|
Rodriguez-Vieitez E, Kumar A, Malarte ML, Ioannou K, Rocha FM, Chiotis K. Imaging Neuroinflammation: Quantification of Astrocytosis in a Multitracer PET Approach. Methods Mol Biol 2024; 2785:195-218. [PMID: 38427196 DOI: 10.1007/978-1-0716-3774-6_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
The recent progress in the development of in vivo biomarkers is rapidly changing how neurodegenerative diseases are conceptualized and diagnosed and how clinical trials are designed today. Alzheimer's disease (AD) - the most common neurodegenerative disorder - is characterized by a complex neuropathology involving the deposition of extracellular amyloid-β (Aβ) plaques and intracellular neurofibrillary tangles (NFTs) of hyperphosphorylated tau proteins, accompanied by the activation of glial cells, i.e., astrocytes and microglia, and neuroinflammatory response, leading to neurodegeneration and cognitive dysfunction. An increasing diversity of positron emission tomography (PET) imaging radiotracers is available to selectively target the different pathophysiological processes of AD. Along with the success of Aβ PET and the more recent tau PET imaging, there is a great interest to develop PET tracers to image glial reactivity and neuroinflammation. While most research to date has focused on imaging microgliosis, there is an upsurge of interest in imaging reactive astrocytes in the AD continuum. There is increasing evidence that reactive astrocytes are morphologically and functionally heterogeneous, with different subtypes that express different markers and display various homeostatic or detrimental roles across disease stages. Therefore, multiple biomarkers are desirable to unravel the complex phenomenon of reactive astrocytosis. In the field of in vivo PET imaging in AD, the research concerning reactive astrocytes has predominantly focused on targeting monoamine oxidase B (MAO-B), most often using either 11C-deuterium-L-deprenyl (11C-DED) or 18F-SMBT-1 PET tracers. Additionally, imidazoline2 binding (I2BS) sites have been imaged using 11C-BU99008 PET. Recent studies in our group using 11C-DED PET imaging suggest that astrocytosis may be present from the early stages of disease development in AD. This chapter provides a detailed description of the practical approach used for the analysis of 11C-DED PET imaging data in a multitracer PET paradigm including 11C-Pittsburgh compound B (11C-PiB) and 18F-fluorodeoxyglucose (18F-FDG). The multitracer PET approach allows investigating the comparative regional and temporal patterns of in vivo brain astrocytosis, fibrillar Aβ deposition, glucose metabolism, and brain structural changes. It may also contribute to understanding the potential role of novel plasma biomarkers of reactive astrocytes, in particular the glial fibrillary acidic protein (GFAP), at different stages of disease progression. This chapter attempts to stimulate further research in the field, including the development of novel PET tracers that may allow visualizing different aspects of the complex astrocytic and microglial response in neurodegenerative diseases. Progress in the field will contribute to the incorporation of PET imaging of glial reactivity and neuroinflammation as biomarkers with clinical application and motivate further investigation on glial cells as therapeutic targets in AD and other neurodegenerative diseases.
Collapse
Affiliation(s)
- Elena Rodriguez-Vieitez
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
- Division of Neurogeriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
| | - Amit Kumar
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Mona-Lisa Malarte
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Konstantinos Ioannou
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Filipa M Rocha
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Konstantinos Chiotis
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
- Department of Neurology, Karolinska University Hospital, Stockholm, Sweden
| |
Collapse
|
17
|
Ozolmez N, Silindir-Gunay M, Volkan-Salanci B. An overview: Radiotracers and nano-radiopharmaceuticals for diagnosis of Parkinson's disease. Appl Radiat Isot 2024; 203:111110. [PMID: 37989065 DOI: 10.1016/j.apradiso.2023.111110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 11/09/2023] [Accepted: 11/10/2023] [Indexed: 11/23/2023]
Abstract
Parkinson's disease (PD) is a widespread progressive neurodegenerative disease. Clinical diagnosis approaches are insufficient to provide an early and accurate diagnosis before a substantial of loss of dopaminergic neurons. PET and SPECT can be used for accurate and early diagnosis of PD by using target-specific radiotracers. Additionally, the importance of BBB penetrating targeted nanosystems has increased in recent years. This article reviews targeted radiopharmaceuticals used in clinics and novel nanocarriers for research purposes of PD imaging.
Collapse
Affiliation(s)
- Nur Ozolmez
- Hacettepe University, Faculty of Pharmacy, Department of Radiopharmacy, Ankara, Turkey.
| | - Mine Silindir-Gunay
- Hacettepe University, Faculty of Pharmacy, Department of Radiopharmacy, Ankara, Turkey.
| | - Bilge Volkan-Salanci
- Hacettepe University, Faculty of Medicine, Department of Nuclear Medicine, Ankara, Turkey.
| |
Collapse
|
18
|
Millard M, Kilian J, Ozenil M, Mogeritsch M, Schwingenschlögl-Maisetschläger V, Holzer W, Hacker M, Langer T, Pichler V. Design, synthesis and preclinical evaluation of muscarine receptor antagonists via a scaffold-hopping approach. Eur J Med Chem 2023; 262:115891. [PMID: 37897926 DOI: 10.1016/j.ejmech.2023.115891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/19/2023] [Accepted: 10/19/2023] [Indexed: 10/30/2023]
Abstract
Our research group recently identified a rearrangement product of pirenzepine as starting point for a comprehensive rational drug design approach towards orthosteric muscarinic acetylcholine receptor ligands. Chemical reduction and bioscaffold hop lead to the development of sixteen promising compounds featuring either a benzimidazole or carbamate moiety, all exhibiting comparable pharmacophoric characteristics. The synthesized compounds were characterized by NMR, HR-MS, and RP-HPLC techniques. Subsequent evaluation encompassed binding affinity assessment on CHO-hM1-5 cells, mode of action determination, and analysis of physico-chemical parameters. The CNS MPO score indicated favorable drug-like attributes and potential CNS activity for the antagonistic ligands. The most promising compounds displayed Ki-values within a desirable low nanomolar range, and their structural features allow for potential carbon-11 radiolabeling. Our optimization efforts resulted in compounds with a remarkable 138-fold increase in binding affinity compared to the previously mentioned rearrangement product towards human M5, suggesting their prospective utility in positron emission tomography applications.
Collapse
Affiliation(s)
- Marlon Millard
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Jonas Kilian
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria; Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences, University of Vienna, Vienna, Austria
| | - Marius Ozenil
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria
| | - Mariella Mogeritsch
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Verena Schwingenschlögl-Maisetschläger
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria; Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences, University of Vienna, Vienna, Austria
| | - Wolfgang Holzer
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Marcus Hacker
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria
| | - Thierry Langer
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Verena Pichler
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria.
| |
Collapse
|
19
|
Ramos-Torres K, Sun Y, Takahashi K, Zhou YP, Brugarolas P. Common anesthetic used in preclinical PET imaging inhibits metabolism of the PET tracer [ 18 F]3F4AP. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.14.571690. [PMID: 38168265 PMCID: PMC10760107 DOI: 10.1101/2023.12.14.571690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
PET imaging studies in laboratory animals are almost always performed under isoflurane anesthesia to ensure that the subject stays still during the image acquisition. Isoflurane is effective, safe, and easy to use, and it is generally assumed to not have an impact on the imaging results. Motivated by marked differences observed in [ 18 F]3F4AP brain uptake and metabolism between human and nonhuman primate studies, this study investigates the possible effect of isoflurane on [ 18 F]3F4AP metabolism and brain uptake. Isoflurane was found to largely abolish tracer metabolism in mice resulting in a 3.3-fold higher brain uptake in anesthetized mice at 35 min post radiotracer administration, which replicated the observed effect in unanesthetized humans and anesthetized monkeys. This effect is attributed to isoflurane's interference in the CYP2E1-mediated breakdown of [ 18 F]3F4AP, which was confirmed by reproducing a higher brain uptake and metabolic stability upon treatment with the known CYP2E1 inhibitor disulfiram. These findings underscore the critical need to examine the effect of isoflurane in PET imaging studies before translating tracers to humans that will be scanned without anesthesia.
Collapse
|
20
|
Li Y, Wang J. Site-specifically radiolabeled nanobodies for imaging blood-brain barrier penetration and targeting in the brain. J Labelled Comp Radiopharm 2023; 66:444-451. [PMID: 37873934 PMCID: PMC10842159 DOI: 10.1002/jlcr.4069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 09/22/2023] [Accepted: 10/03/2023] [Indexed: 10/25/2023]
Abstract
Nanobodies (Nbs) hold significant potential in molecular imaging due to their unique characteristics. However, there are challenges to overcome when it comes to brain imaging. To address these obstacles, collaborative efforts and interdisciplinary research are needed. This article aims to raise awareness and encourage collaboration among researchers from various fields to find solutions for effective brain imaging using Nbs. By fostering cooperation and knowledge sharing, we can make progress in overcoming the existing limitations and pave the way for improved molecular imaging techniques in the future.
Collapse
Affiliation(s)
- Yingbo Li
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Junfeng Wang
- Gordon Center for Medical Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
21
|
Yu Z, Huang Y, Chen H, Jiang Z, Li C, Xie Y, Li Z, Cheng X, Liu Y, Li S, Liang Y, Wu Z. Design, Synthesis, and Evaluation of 18F-Labeled Tracers Targeting Fibroblast Activation Protein for Brain Imaging. ACS Pharmacol Transl Sci 2023; 6:1745-1757. [PMID: 37974629 PMCID: PMC10644484 DOI: 10.1021/acsptsci.3c00187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 10/02/2023] [Accepted: 10/04/2023] [Indexed: 11/19/2023]
Abstract
Fibroblast activation protein (FAP) is closely related to central nervous system diseases such as stroke and brain tumors, but PET tracers that can be used for brain imaging have not been reported. Here, we designed, synthesized, and evaluated 18F-labeled UAMC1110 derivatives suitable for brain imaging targeting FAP. By substituting the F atom for the H atom on the aromatic ring of compound UAMC1110, 1a-c were designed and prepared. 1a-c were confirmed to have a high affinity for FAP through molecular docking and enzyme assay. [18F]1a-c were successfully prepared and confirmed to have high affinity. The stability in vivo indicates that no obvious metabolites of [18F]1a,b were found in the plasma 1 h after injection, which is beneficial for brain imaging. In vitro cell uptake experiments showed that [18F]1a,b and [68Ga]FAPI04 exhibited similar uptake and internalization rates. PET imaging of U87MG subcutaneous tumor showed that [18F]1a,b could penetrate the blood-brain barrier with higher uptake and longer retention time than [68Ga]FAPI04 (uptake at 62.5 min, 1.06 ± 0.23, 1.09 ± 0.25% ID/g vs 0.21 ± 0.10% ID/g, respectively). The brain-to-blood ratios of [18F]1a,b were better than [68Ga]FAPI04. Biodistribution and PET imaging showed that [18F]1a had better uptake on tumors and a higher tumor-to-muscle ratio than [18F]1b and [68Ga]FAPI04. Further imaging of U87MG intracranial glioma showed that [18F]1a outlined high-contrast gliomas in a short period of time compared to [18F]1b. Therefore, [18F]1a is expected to be useful in the diagnosis of FAP-related brain diseases.
Collapse
Affiliation(s)
- Ziyue Yu
- Beijing
Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry
of Science and Technology, Collaborative Innovation Center for Brain
Disorders, Capital Medical University, Beijing 100069, China
| | - Yong Huang
- Department
of Nuclear Medicine, National Cancer Center, National Clinical Research
Center for Cancer, Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union
Medical College, Shenzhen 518116, China
| | - Hualong Chen
- Beijing
Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry
of Science and Technology, Collaborative Innovation Center for Brain
Disorders, Capital Medical University, Beijing 100069, China
| | - Zeng Jiang
- Beijing
Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry
of Science and Technology, Collaborative Innovation Center for Brain
Disorders, Capital Medical University, Beijing 100069, China
| | - Chengze Li
- Department
of Nuclear Medicine, National Cancer Center, National Clinical Research
Center for Cancer, Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union
Medical College, Shenzhen 518116, China
| | - Yi Xie
- Beijing
Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry
of Science and Technology, Collaborative Innovation Center for Brain
Disorders, Capital Medical University, Beijing 100069, China
| | - Zhongjing Li
- Department
of Nuclear Medicine, National Cancer Center, National Clinical Research
Center for Cancer, Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union
Medical College, Shenzhen 518116, China
| | - Xuebo Cheng
- Beijing
Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry
of Science and Technology, Collaborative Innovation Center for Brain
Disorders, Capital Medical University, Beijing 100069, China
| | - Yajing Liu
- School
of Pharmaceutical Science, Capital Medical
University, Beijing 100069, China
| | - Shengli Li
- Department
of Laboratory Animal Science, Capital Medical
University, Beijing 100069, China
| | - Ying Liang
- Department
of Nuclear Medicine, National Cancer Center, National Clinical Research
Center for Cancer, Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union
Medical College, Shenzhen 518116, China
| | - Zehui Wu
- Beijing
Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry
of Science and Technology, Collaborative Innovation Center for Brain
Disorders, Capital Medical University, Beijing 100069, China
| |
Collapse
|
22
|
Altomonte S, Pike VW. Candidate Tracers for Imaging Colony-Stimulating Factor 1 Receptor in Neuroinflammation with Positron Emission Tomography: Issues and Progress. ACS Pharmacol Transl Sci 2023; 6:1632-1650. [PMID: 37974622 PMCID: PMC10644394 DOI: 10.1021/acsptsci.3c00213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Indexed: 11/19/2023]
Abstract
The tyrosine kinase, colony-stimulating factor 1 receptor (CSF1R), has attracted attention as a potential biomarker of neuroinflammation for imaging studies with positron emission tomography (PET), especially because of its location on microglia and its role in microglia proliferation. The development of an effective radiotracer for specifically imaging and quantifying brain CSF1R is highly challenging. Here we review the progress that has been made on PET tracer development and discuss issues that have arisen and which remain to be addressed and resolved.
Collapse
Affiliation(s)
- Stefano Altomonte
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes
of Health, Building 10,
B3 C346A, 10 Center Drive, Bethesda, Maryland 20892, United States
| | - Victor W. Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes
of Health, Building 10,
B3 C346A, 10 Center Drive, Bethesda, Maryland 20892, United States
| |
Collapse
|
23
|
Lynch C, Downey JW, Zhang Y, Hooker JM, Levin MD. Core-Labeling (Radio) Synthesis of Phenols. Org Lett 2023; 25:7230-7235. [PMID: 37751441 PMCID: PMC10563162 DOI: 10.1021/acs.orglett.3c02838] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Indexed: 09/28/2023]
Abstract
We report a method that enables the fast incorporation of carbon isotopes into the ipso carbon of phenols. Our approach relies on the synthesis of a 1,5-dibromo-1,4-pentadiene precursor, which upon lithium-halogen exchange followed by treatment with carbonate esters results in a formal [5 + 1] cyclization to form the phenol product. Using this strategy, we have prepared 12 1-13C-labeled phenols, show proof-of-concept for the labeling of phenols with carbon-14, and demonstrate phenol synthesis directly from cyclotron-produced [11C]CO2.
Collapse
Affiliation(s)
- Colin
F. Lynch
- Department
of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Joseph W. Downey
- Athinoula
A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts 02129, United States
| | - Yongliang Zhang
- Department
of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Jacob M. Hooker
- Athinoula
A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts 02129, United States
- Department
of Radiology, Harvard Medical School, Boston, Massachusetts 02115, United States
- Lurie
Center for Autism, Massachusetts General
Hospital, Lexington, Massachusetts 02421, United States
| | - Mark D. Levin
- Department
of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| |
Collapse
|
24
|
Shah S, Turner ML, Chen X, Ances BM, Hammoud DA, Tucker EW. The Promise of Molecular Imaging: Focus on Central Nervous System Infections. J Infect Dis 2023; 228:S311-S321. [PMID: 37788502 PMCID: PMC11009511 DOI: 10.1093/infdis/jiad223] [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: 10/05/2023] Open
Abstract
Central nervous system (CNS) infections can lead to high mortality and severe morbidity. Diagnosis, monitoring, and assessing response to therapy of CNS infections is particularly challenging with traditional tools, such as microbiology, due to the dangers associated with invasive CNS procedures (ie, biopsy or surgical resection) to obtain tissues. Molecular imaging techniques like positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging have long been used to complement anatomic imaging such as computed tomography (CT) and magnetic resonance imaging (MRI), for in vivo evaluation of disease pathophysiology, progression, and treatment response. In this review, we detail the use of molecular imaging to delineate host-pathogen interactions, elucidate antimicrobial pharmacokinetics, and monitor treatment response. We also discuss the utility of pathogen-specific radiotracers to accurately diagnose CNS infections and strategies to develop radiotracers that would cross the blood-brain barrier.
Collapse
Affiliation(s)
- Swati Shah
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Mitchell L Turner
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Xueyi Chen
- Department of Pediatrics, Center for Infection and Inflammation Imaging Research, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Beau M Ances
- Department of Neurology, Washington University, St Louis, Missouri, USA
| | - Dima A Hammoud
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Elizabeth W Tucker
- Department of Anesthesiology and Critical Care Medicine, Center for Infection and Inflammation Imaging Research, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
25
|
Arjmand S, Bender D, Jakobsen S, Wegener G, Landau AM. Peering into the Brain's Estrogen Receptors: PET Tracers for Visualization of Nuclear and Extranuclear Estrogen Receptors in Brain Disorders. Biomolecules 2023; 13:1405. [PMID: 37759805 PMCID: PMC10526964 DOI: 10.3390/biom13091405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/12/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
Estrogen receptors (ERs) play a multitude of roles in brain function and are implicated in various brain disorders. The use of positron emission tomography (PET) tracers for the visualization of ERs' intricate landscape has shown promise in oncology but remains limited in the context of brain disorders. Despite recent progress in the identification and development of more selective ligands for various ERs subtypes, further optimization is necessary to enable the reliable and efficient imaging of these receptors. In this perspective, we briefly touch upon the significance of estrogen signaling in the brain and raise the setbacks associated with the development of PET tracers for identification of specific ERs subtypes in the brain. We then propose avenues for developing efficient PET tracers to non-invasively study the dynamics of ERs in the brain, as well as neuropsychiatric diseases associated with their malfunction in a longitudinal manner. This perspective puts several potential candidates on the table and highlights the unmet needs and areas requiring further research to unlock the full potential of PET tracers for ERs imaging, ultimately aiding in deepening our understanding of ERs and forging new avenues for potential therapeutic strategies.
Collapse
Affiliation(s)
- Shokouh Arjmand
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark;
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital, 8200 Aarhus, Denmark; (D.B.); (S.J.)
| | - Dirk Bender
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital, 8200 Aarhus, Denmark; (D.B.); (S.J.)
| | - Steen Jakobsen
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital, 8200 Aarhus, Denmark; (D.B.); (S.J.)
| | - Gregers Wegener
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark;
| | - Anne M. Landau
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark;
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital, 8200 Aarhus, Denmark; (D.B.); (S.J.)
| |
Collapse
|
26
|
Marik J, Rich S, Deshmukh G, Zhang D, Tinianow J, Cai J, Wong S, Bobba S, DeMent K, Liu N, Halladay J, Sanabria-Bohórquez S, Cheruzel L, Khojasteh C. GTP1 metabolic stability assessment: A study of the tau PET tracer [ 18F]GTP1. Nucl Med Biol 2023; 124-125:108386. [PMID: 37699300 DOI: 10.1016/j.nucmedbio.2023.108386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 08/31/2023] [Accepted: 09/01/2023] [Indexed: 09/14/2023]
Abstract
Tau PET imaging using the tau specific PET tracer [18F]GTP1 has been and is part of therapeutic trials in Alzheimer's disease to monitor the accumulation of tau aggregates in the brain. Herein, we examined the metabolic processes of GTP1 and assessed the influence of smoking on its metabolism through in vitro assays. The tracer metabolic profile was assessed by incubating GTP1 with human liver microsomes (HLM) and human hepatocytes. Since smoking strongly stimulates the CYP1A2 enzyme activity, we incubated GTP1 with recombinant CYP1A2 to evaluate the role of the enzyme in tracer metabolism. It was found that GTP1 could form up to eleven oxidative metabolites with higher polarity than the parent. Only a small amount (2.6 % at 60 min) of a defluorinated metabolite was detected in HLM and human hepatocytes incubations highlighting the stability of GTP1 with respect to enzymatic defluorination. Moreover, the major GTP1 metabolites were not the product of CYP1A2 activity suggesting that smoking may not impact in vivo tracer metabolism and subsequently GTP1 brain kinetics.
Collapse
Affiliation(s)
- Jan Marik
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA.
| | - Sharyl Rich
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Gauri Deshmukh
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Donglu Zhang
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Jeff Tinianow
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Jingwei Cai
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Susan Wong
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Sudheer Bobba
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Kevin DeMent
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Ning Liu
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Jason Halladay
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Sandra Sanabria-Bohórquez
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Lionel Cheruzel
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| | - Cyrus Khojasteh
- Genentech Research and Early Development (gRED), Genentech Inc., 1 DNA way, South San Francisco, CA 94080, USA
| |
Collapse
|
27
|
Sun Y, Rodríguez-Rangel S, Zhang LL, Sánchez-Rodríguez JE, Brugarolas P. Chemical and biophysical characterization of novel potassium channel blocker 3-fluoro-5-methylpyridin-4-amine. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.08.550404. [PMID: 37609160 PMCID: PMC10441322 DOI: 10.1101/2023.08.08.550404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
4-aminopyridine (4AP) is a potassium (K+) channel blocker used clinically to improve walking in people with multiple sclerosis (MS). 4AP binds to exposed K+ channels in demyelinated axons, reducing the leakage of intracellular K+ and enhancing impulse conduction. Multiple derivatives of 4AP capable of blocking K+ channels have been reported including three radiolabeled with positron emitting isotopes for imaging demyelinated lesions using positron emission tomography (PET). Here, we describe 3-fluoro-5-methylpyridin-4-amine (5Me3F4AP), a novel K+ channel blocker with potential application in PET. 5Me3F4AP has comparable potency to 4AP and the PET tracer 3-fluoro-4-aminopyridine (3F4AP). Compared to 3F4AP, 5Me3F4AP is more lipophilic (logD = 0.664 ± 0.005 vs. 0.414 ± 0.002) and slightly more basic (pKa = 7.46 ± 0.01 vs. 7.37 ± 0.07). In addition, 5Me3F4AP appears to be more permeable to an artificial brain membrane and more stable towards oxidation by the cytochrome P450 enzyme family 2 subfamily E member 1 (CYP2E1), responsible for the metabolism of 4AP and 3F4AP. Taken together, 5Me3F4AP has promising properties for PET imaging warranting additional investigation.
Collapse
Affiliation(s)
- Yang Sun
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | | | - Lauren L. Zhang
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | | | - Pedro Brugarolas
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| |
Collapse
|
28
|
Yan X, Siméon FG, Liow JS, Morse CL, Montero Santamaria JA, Jenkins M, Manly LS, Van Buskirk M, Zoghbi SS, Pike VW, Innis RB, Zanotti-Fregonara P. In vivo evaluation of a novel 18F-labeled PET radioligand for translocator protein 18 kDa (TSPO) in monkey brain. Eur J Nucl Med Mol Imaging 2023; 50:2962-2970. [PMID: 37249618 PMCID: PMC10382351 DOI: 10.1007/s00259-023-06270-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 05/18/2023] [Indexed: 05/31/2023]
Abstract
PURPOSE [18F]SF51 was previously found to have high binding affinity and selectivity for 18 kDa translocator protein (TSPO) in mouse brain. This study sought to assess the ability of [18F]SF51 to quantify TSPO in rhesus monkey brain. METHODS Positron emission tomography (PET) imaging was performed in monkey brain (n = 3) at baseline and after pre-blockade with the TSPO ligands PK11195 and PBR28. TSPO binding was calculated as total distribution volume corrected for free parent fraction in plasma (VT/fP) using a two-tissue compartment model. Receptor occupancy and nondisplaceable uptake were determined via Lassen plot. Binding potential (BPND) was calculated as the ratio of specific binding to nondisplaceable uptake. Time stability of VT was used as an indirect probe to detect radiometabolite accumulation in the brain. In vivo and ex vivo experiments were performed in mice to determine the distribution of the radioligand. RESULTS After [18F]SF51 injection, the concentration of brain radioactivity peaked at 2.0 standardized uptake value (SUV) at ~ 10 min and declined to 30% of the peak at 180 min. VT/fP at baseline was generally high (203 ± 15 mL· cm-3) and decreased by ~ 90% after blockade with PK11195. BPND of the whole brain was 7.6 ± 4.3. VT values reached levels similar to terminal 180-min values by 100 min and remained relatively stable thereafter with excellent identifiability (standard errors < 5%), suggesting that no significant radiometabolites accumulated in the brain. Ex vivo experiments in mouse brain showed that 96% of radioactivity was parent. No significant uptake was observed in the skull, suggesting a lack of defluorination in vivo. CONCLUSION The results demonstrate that [18F]SF51 is an excellent radioligand that can quantify TSPO with a good ratio of specific to nondisplaceable uptake and has minimal radiometabolite accumulation in brain. Collectively, the results suggest that [18F]SF51 warrants further evaluation in humans.
Collapse
Affiliation(s)
- Xuefeng Yan
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA.
| | - Fabrice G Siméon
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Jeih-San Liow
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Cheryl L Morse
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Jose A Montero Santamaria
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Madeline Jenkins
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Lester S Manly
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Maia Van Buskirk
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Sami S Zoghbi
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Victor W Pike
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Robert B Innis
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Paolo Zanotti-Fregonara
- Molecular Imaging Branch, National Institute of Mental Health, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| |
Collapse
|
29
|
Lo CH, Zeng J. Defective lysosomal acidification: a new prognostic marker and therapeutic target for neurodegenerative diseases. Transl Neurodegener 2023; 12:29. [PMID: 37287072 DOI: 10.1186/s40035-023-00362-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 05/12/2023] [Indexed: 06/09/2023] Open
Abstract
Lysosomal acidification dysfunction has been implicated as a key driving factor in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Multiple genetic factors have been linked to lysosomal de-acidification through impairing the vacuolar-type ATPase and ion channels on the organelle membrane. Similar lysosomal abnormalities are also present in sporadic forms of neurodegeneration, although the underlying pathogenic mechanisms are unclear and remain to be investigated. Importantly, recent studies have revealed early occurrence of lysosomal acidification impairment before the onset of neurodegeneration and late-stage pathology. However, there is a lack of methods for organelle pH monitoring in vivo and a dearth of lysosome-acidifying therapeutic agents. Here, we summarize and present evidence for the notion of defective lysosomal acidification as an early indicator of neurodegeneration and urge the critical need for technological advancement in developing tools for lysosomal pH monitoring and detection both in vivo and for clinical applications. We further discuss current preclinical pharmacological agents that modulate lysosomal acidification, including small molecules and nanomedicine, and their potential clinical translation into lysosome-targeting therapies. Both timely detection of lysosomal dysfunction and development of therapeutics that restore lysosomal function represent paradigm shifts in targeting neurodegenerative diseases.
Collapse
Affiliation(s)
- Chih Hung Lo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore.
| | - Jialiu Zeng
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore.
| |
Collapse
|
30
|
Moon SH, El Fakhri G, Zhang Z, Brownell AL, Wang J. Fully Automated Radiosynthesis of [ 18F]mG4P027 for mGluR4 Imaging. IRADIOLOGY 2023; 1:120-127. [PMID: 37496513 PMCID: PMC10371389 DOI: 10.1002/ird3.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 05/18/2023] [Indexed: 07/28/2023]
Abstract
Fluorine-18 labeled N-(4-chloro-3-(((fluoro-18F)methyl-d2)thio)phenyl)picolinamide, [18F]mG4P027, is a potent positron emission tomography (PET) radiotracer for metabotropic glutamate receptor 4 (mGluR4). Our previous in vitro and in vivo evaluations have demonstrated that this tracer is promising for further translational studies. To automate the radiosynthesis of [18F]mG4P027, significant modifications were made to the manual process by carefully examining this process and addressing the root causes of the challenges associated with its automation. We successfully implemented its automated radiosynthesis using the TRACERlab FX2N module and consequently, obtained a high-purity radiolabeled [18F]mG4P027 in high yield, meeting the requirements for future human studies.
Collapse
Affiliation(s)
- Sung-Hyun Moon
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114 (USA)
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114 (USA)
| | - Zhaoda Zhang
- Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114 (USA)
| | - Anna-Liisa Brownell
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114 (USA)
| | - Junfeng Wang
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114 (USA)
| |
Collapse
|
31
|
Högnäsbacka A, Poot AJ, Kooijman E, Schuit RC, Schreurs M, Verlaan M, van den Hoek J, Heideman DAM, Beaino W, van Dongen GAMS, Vugts DJ, Windhorst AD. Synthesis and preclinical evaluation of two osimertinib isotopologues labeled with carbon-11 as PET tracers targeting the tyrosine kinase domain of the epidermal growth factor receptor. Nucl Med Biol 2023; 120-121:108349. [PMID: 37209556 DOI: 10.1016/j.nucmedbio.2023.108349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/05/2023] [Accepted: 04/18/2023] [Indexed: 05/22/2023]
Abstract
INTRODUCTION Osimertinib is a third-generation tyrosine kinase inhibitor (TKI) that is able to inhibit the EGFR treatment resistance mutation T790M and primary EGFR mutations Del19 and L858R. The aim of the study was to evaluate the potential of carbon-11 labeled osimertinib to be used as a tracer for the PET imaging of tumors bearing the T790M mutation. METHODS Osimertinib was labeled with carbon-11 at two positions, and the effect of the labeling position on the metabolism and biodistribution was studied in female nu/nu mice. The mutation status specificity of osimertinib was confirmed in vitro in a cell growth inhibition experiment, and the tumor-targeting potential of the carbon-11 isotopologues was evaluated using female nu/nu mice xenografted with NSCLC cell lines; the wild-type EGFR expressing A549, the primary Del19 EGFR mutated HCC827 and the resistance T790M/L858R mutated H1975. One of the osimertinib tracers was selected based on the results acquired and evaluated for tracer specificity and selectivity by assessment of tumor uptake in a PET study where HCC827 tumor-bearing mice were pretreated with osimertinib or afatinib. RESULTS [Methylindole-11C]- and [dimethylamine-11C]osimertinib were synthesized by 11C-methylation of precursors AZ5104 and AZ7550, respectively. Rapid metabolism of both analogs of [11C]osimertinib was observed. Although the tumor uptake and retention of [methylindole-11C]- and [dimethylamine-11C]osimertinib in tumors were similar, the tumor-to-muscle ratios appeared to be higher for [methylindole-11C]osimertinib. The highest uptake, tumor-to-blood, and tumor-to-muscle ratio were observed in the Del19 EGFR mutated HCC827 tumors. However, the specificity and selectivity of [methylindole-11C]osimertinib PET could not be demonstrated in HCC827 tumors. The uptake of [methylindole-11C]osimertinib was not significantly higher in T790M resistance mutated H1975 xenografts compared to the negative control cell line A549. CONCLUSIONS Osimertinib was successfully labeled at two positions with carbon-11, yielding two EGFR PET tracers, [methylindole-11C]osimertinib and [dimethylamine-11C]osimertinib. The preclinical evaluation demonstrated uptake and retention in three NSCLC xenografts; A549, HCC827, and H1975. The highest uptake was observed in the primary Del19 EGFR mutated HCC827. The ability of [methylindole-11C]osimertinib to distinguish between the T790M resistance mutated H1975 xenografts and the wild-type EGFR expressing A549 could not be confirmed in the ex vivo study.
Collapse
Affiliation(s)
- Antonia Högnäsbacka
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands.
| | - Alex J Poot
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| | - Esther Kooijman
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| | - Robert C Schuit
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| | - Maxime Schreurs
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| | - Mariska Verlaan
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| | - Johan van den Hoek
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| | - Daniëlle A M Heideman
- Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands; Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Pathology, De Boelelaan 1117, Amsterdam, the Netherlands
| | - Wissam Beaino
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| | - Guus A M S van Dongen
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| | - Danielle J Vugts
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| | - Albert D Windhorst
- Amsterdam UMC location Vrije Universiteit Amsterdam, Dept. Radiology & Nuclear Medicine, De Boelelaan 1117, Amsterdam, the Netherlands; Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, the Netherlands
| |
Collapse
|
32
|
Ozsahin I, Onakpojeruo EP, Uzun B, Uzun Ozsahin D, Butler TA. A Multi-Criteria Decision Aid Tool for Radiopharmaceutical Selection in Tau PET Imaging. Pharmaceutics 2023; 15:pharmaceutics15041304. [PMID: 37111789 PMCID: PMC10147085 DOI: 10.3390/pharmaceutics15041304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 04/09/2023] [Accepted: 04/19/2023] [Indexed: 04/29/2023] Open
Abstract
The accumulation of pathologically misfolded tau is a feature shared by a group of neurodegenerative disorders collectively referred to as tauopathies. Alzheimer's disease (AD) is the most prevalent of these tauopathies. Immunohistochemical evaluation allows neuropathologists to visualize paired-helical filaments (PHFs)-tau pathological lesions, but this is possible only after death and only shows tau in the portion of brain sampled. Positron emission tomography (PET) imaging allows both the quantitative and qualitative analysis of pathology over the whole brain of a living subject. The ability to detect and quantify tau pathology in vivo using PET can aid in the early diagnosis of AD, provide a way to monitor disease progression, and determine the effectiveness of therapeutic interventions aimed at reducing tau pathology. Several tau-specific PET radiotracers are now available for research purposes, and one is approved for clinical use. This study aims to analyze, compare, and rank currently available tau PET radiotracers using the fuzzy preference ranking organization method for enrichment of evaluations (PROMETHEE), which is a multi-criteria decision-making (MCDM) tool. The evaluation is based on relatively weighted criteria, such as specificity, target binding affinity, brain uptake, brain penetration, and rates of adverse reactions. Based on the selected criteria and assigned weights, this study shows that a second-generation tau tracer, [18F]RO-948, may be the most favorable. This flexible method can be extended and updated to include new tracers, additional criteria, and modified weights to help researchers and clinicians select the optimal tau PET tracer for specific purposes. Additional work is needed to confirm these results, including a systematic approach to defining and weighting criteria and clinical validation of tracers in different diseases and patient populations.
Collapse
Affiliation(s)
- Ilker Ozsahin
- Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, NY 10065, USA
- Operational Research Center in Healthcare, Near East University, Nicosia 99138, TRNC, Turkey
| | | | - Berna Uzun
- Operational Research Center in Healthcare, Near East University, Nicosia 99138, TRNC, Turkey
- Department of Statistics, Carlos III University of Madrid, Getafe, 28903 Madrid, Spain
| | - Dilber Uzun Ozsahin
- Operational Research Center in Healthcare, Near East University, Nicosia 99138, TRNC, Turkey
- Medical Diagnostic Imaging Department, College of Health Sciences & Research Institute for Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 26666, United Arab Emirates
| | - Tracy A Butler
- Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, NY 10065, USA
| |
Collapse
|
33
|
Korff M, Steigerwald R, Bechthold E, Schepmann D, Schreiber JA, Meuth SG, Seebohm G, Wünsch B. Chemical, pharmacodynamic and pharmacokinetic characterization of the GluN2B receptor antagonist 3-(4-phenylbutyl)-2,3,4,5-tetrahydro-1 H-3-benzazepine-1,7-diol - starting point for PET tracer development. Biol Chem 2023; 404:279-289. [PMID: 36215695 DOI: 10.1515/hsz-2022-0222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 09/22/2022] [Indexed: 11/15/2022]
Abstract
GluN2B-NMDA receptors play a key role in several neurological and neurodegenerative disorders. In order to develop novel negative allosteric GluN2B-NMDA receptor modulators, the concept of conformational restriction was pursued, i.e. the flexible aminoethanol substructure of ifenprodil was embedded into a more rigid tetrahydro-3-benzazepine system. The resulting tetrahydro-3-benzazepine-1,7-diol (±)-2 (WMS-1410) showed promising receptor affinity in receptor binding studies (K i = 84 nM) as well as pharmacological activity in two-electrode-voltage-clamp experiments (IC 50 = 116 nM) and in cytoprotective assays (IC 50 = 18.5 nM). The interactions of (R)-2 with the ifenprodil binding site of GluN2B-NMDA receptors were analyzed on the molecular level and the "foot-in-the-door" mechanism was developed. Due to promising pharmacokinetic parameters (logD7.4 = 1.68, plasma protein binding of 76-77%, sufficient metabolic stability) F-substituted analogs were prepared and evaluated as tracers for positron emission tomography (PET). Both fluorine-18-labeled PET tracers [18F]11 and [18F]15 showed high brain uptake, specific accumulation in regions known for high GluN2B-NMDA receptor expression, but no interactions with σ 1 receptors. Radiometabolites were not observed in the brain. Both PET tracers might be suitable for application in humans.
Collapse
Affiliation(s)
- Marvin Korff
- Chemical Biology of Ion Channels (Chembion), Westfälische Wilhelms-Universität Münster, GRK 2515 Munster, Germany
- Westfälische Wilhelms-Universität Münster, Institut für Pharmazeutische und Medizinische Chemie, Corrensstraße 48, D-48149 Münster, Germany
| | - Ruben Steigerwald
- Chemical Biology of Ion Channels (Chembion), Westfälische Wilhelms-Universität Münster, GRK 2515 Munster, Germany
- Westfälische Wilhelms-Universität Münster, Institut für Pharmazeutische und Medizinische Chemie, Corrensstraße 48, D-48149 Münster, Germany
| | - Elena Bechthold
- Chemical Biology of Ion Channels (Chembion), Westfälische Wilhelms-Universität Münster, GRK 2515 Munster, Germany
- Westfälische Wilhelms-Universität Münster, Institut für Pharmazeutische und Medizinische Chemie, Corrensstraße 48, D-48149 Münster, Germany
| | - Dirk Schepmann
- Westfälische Wilhelms-Universität Münster, Institut für Pharmazeutische und Medizinische Chemie, Corrensstraße 48, D-48149 Münster, Germany
| | - Julian A Schreiber
- Westfälische Wilhelms-Universität Münster, Institut für Pharmazeutische und Medizinische Chemie, Corrensstraße 48, D-48149 Münster, Germany
- Department of Cardiovascular Medicine, Westfälische Wilhelms-Universität Münster, Cellular Electrophysiology and Molecular Biology, Institute for Genetics of Heart Diseases (IfGH), University Hospital Münster, Robert-Koch-Str. 45, D-48149 Münster, Germany
| | - Sven G Meuth
- Chemical Biology of Ion Channels (Chembion), Westfälische Wilhelms-Universität Münster, GRK 2515 Munster, Germany
- Department of Neurology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Guiscard Seebohm
- Chemical Biology of Ion Channels (Chembion), Westfälische Wilhelms-Universität Münster, GRK 2515 Munster, Germany
- Department of Cardiovascular Medicine, Westfälische Wilhelms-Universität Münster, Cellular Electrophysiology and Molecular Biology, Institute for Genetics of Heart Diseases (IfGH), University Hospital Münster, Robert-Koch-Str. 45, D-48149 Münster, Germany
| | - Bernhard Wünsch
- Chemical Biology of Ion Channels (Chembion), Westfälische Wilhelms-Universität Münster, GRK 2515 Munster, Germany
- Westfälische Wilhelms-Universität Münster, Institut für Pharmazeutische und Medizinische Chemie, Corrensstraße 48, D-48149 Münster, Germany
| |
Collapse
|
34
|
Neumaier F, Zlatopolskiy BD, Neumaier B. Mutated Isocitrate Dehydrogenase (mIDH) as Target for PET Imaging in Gliomas. Molecules 2023; 28:molecules28072890. [PMID: 37049661 PMCID: PMC10096429 DOI: 10.3390/molecules28072890] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/21/2023] [Accepted: 03/21/2023] [Indexed: 04/14/2023] Open
Abstract
Gliomas are the most common primary brain tumors in adults. A diffuse infiltrative growth pattern and high resistance to therapy make them largely incurable, but there are significant differences in the prognosis of patients with different subtypes of glioma. Mutations in isocitrate dehydrogenase (IDH) have been recognized as an important biomarker for glioma classification and a potential therapeutic target. However, current clinical methods for detecting mutated IDH (mIDH) require invasive tissue sampling and cannot be used for follow-up examinations or longitudinal studies. PET imaging could be a promising approach for non-invasive assessment of the IDH status in gliomas, owing to the availability of various mIDH-selective inhibitors as potential leads for the development of PET tracers. In the present review, we summarize the rationale for the development of mIDH-selective PET probes, describe their potential applications beyond the assessment of the IDH status and highlight potential challenges that may complicate tracer development. In addition, we compile the major chemical classes of mIDH-selective inhibitors that have been described to date and briefly consider possible strategies for radiolabeling of the most promising candidates. Where available, we also summarize previous studies with radiolabeled analogs of mIDH inhibitors and assess their suitability for PET imaging in gliomas.
Collapse
Affiliation(s)
- Felix Neumaier
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen-Str., 52428 Jülich, Germany
- Institute of Radiochemistry and Experimental Molecular Imaging, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| | - Boris D Zlatopolskiy
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen-Str., 52428 Jülich, Germany
- Institute of Radiochemistry and Experimental Molecular Imaging, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| | - Bernd Neumaier
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen-Str., 52428 Jülich, Germany
- Institute of Radiochemistry and Experimental Molecular Imaging, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| |
Collapse
|
35
|
Dickmann CGF, McDonald AF, Huynh N, Rigopoulos A, Liu Z, Guo N, Osellame LD, Gorman MA, Parker MW, Gan HK, Scott AM, Ackermann U, Burvenich IJG, White JM. Bromodomain and extraterminal protein-targeted probe enables tumour visualisation in vivo using positron emission tomography. Chem Commun (Camb) 2023; 59:3126-3129. [PMID: 36809538 DOI: 10.1039/d2cc04813b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Bromodomain and extraterminal (BET) proteins, a family of epigenetic regulators, have emerged as important oncology drug targets. BET proteins have not been targeted for molecular imaging of cancer. Here, we report the development of a novel molecule radiolabelled with positron emitting fluorine-18, [18F]BiPET-2, and its in vitro and preclinical evaluation in glioblastoma models.
Collapse
Affiliation(s)
- Catherine G Fitzgerald Dickmann
- Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia. .,Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, and School of Cancer Medicine, La Trobe University, Heidelberg, Australia. .,Department of Molecular Imaging and Therapy, Austin Hospital, Heidelberg, Australia
| | - Alexander F McDonald
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, and School of Cancer Medicine, La Trobe University, Heidelberg, Australia. .,Department of Molecular Imaging and Therapy, Austin Hospital, Heidelberg, Australia
| | - Nhi Huynh
- Department of Molecular Imaging and Therapy, Austin Hospital, Heidelberg, Australia
| | - Angela Rigopoulos
- Department of Molecular Imaging and Therapy, Austin Hospital, Heidelberg, Australia
| | - Zhanqi Liu
- Department of Molecular Imaging and Therapy, Austin Hospital, Heidelberg, Australia
| | - Nancy Guo
- Department of Molecular Imaging and Therapy, Austin Hospital, Heidelberg, Australia
| | - Laura D Osellame
- Department of Molecular Imaging and Therapy, Austin Hospital, Heidelberg, Australia
| | - Michael A Gorman
- Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia.
| | - Michael W Parker
- Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia. .,ACRF Facility for Innovative Cancer Drug Discovery, Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia.,ACRF Rational Drug Discovery Centre, St. Vincent's Institute of Medical Research, VIC 3065, Australia
| | - Hui K Gan
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, and School of Cancer Medicine, La Trobe University, Heidelberg, Australia.
| | - Andrew M Scott
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, and School of Cancer Medicine, La Trobe University, Heidelberg, Australia. .,Department of Molecular Imaging and Therapy, Austin Hospital, Heidelberg, Australia.,Faculty of Medicine, University of Melbourne, Parkville, Australia
| | - Uwe Ackermann
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, and School of Cancer Medicine, La Trobe University, Heidelberg, Australia. .,Department of Molecular Imaging and Therapy, Austin Hospital, Heidelberg, Australia
| | - Ingrid J G Burvenich
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, and School of Cancer Medicine, La Trobe University, Heidelberg, Australia.
| | - Jonathan M White
- Bio21 Institute, The University of Melbourne, Parkville, VIC 3010, Australia.
| |
Collapse
|
36
|
An X, Wang J, Tong L, Zhang X, Fu H, Zhang J, Xie H, Huang Y, Jia H. 18F-Labeled o‑aminopyridyl alkynyl radioligands targeting colony-stimulating factor 1 receptor for neuroinflammation imaging. Bioorg Med Chem 2023; 83:117233. [PMID: 36933438 DOI: 10.1016/j.bmc.2023.117233] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 02/24/2023] [Accepted: 03/02/2023] [Indexed: 03/09/2023]
Abstract
We report the design, synthesis and evaluation of five o‑aminopyridyl alkynyl derivatives as colony-stimulating factor 1 receptor (CSF-1R) ligands. Compounds 4 and 5 with the fluoroethoxy group at the meta- or para-position of the phenyl ring possessed nanomolar inhibitory potency against CSF-1R with IC50 values of 7.6 nM and 2.3 nM, respectively. Radioligands [18F]4 and [18F]5 were obtained in radiochemical yields of 17.2 ± 5.3% (n = 5, decay-corrected) and 14.0 ± 4.3% (n = 4, decay-corrected), with radiochemical purity of > 99% and molar activity of 9-12 GBq/μmol (n = 5) and 6-8 GBq/μmol (n = 4), respectively. In biodistribution studies, radioligands [18F]4 and [18F]5 showed moderate brain uptake in male ICR mice with 1.52 ± 0.15 and 0.91 ± 0.07% ID/g, respectively, at 15 min. Metabolic stability studies in mouse brain revealed that [18F]4 exhibited high stability while [18F]5 suffered from low stability. Higher accumulation of [18F]4 in the brain of lipopolysaccharide (LPS)-treated mice was observed, and further pretreatment of BLZ945 or CPPC led to remarkable reduction, indicating specific binding of [18F]4 to CSF-1R.
Collapse
Affiliation(s)
- Xiaodan An
- Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Jingqi Wang
- Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Linjiang Tong
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xiaojun Zhang
- Nuclear Medicine Department, the First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - Hualong Fu
- Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Jinming Zhang
- Nuclear Medicine Department, the First Medical Center of Chinese PLA General Hospital, Beijing 100853, China.
| | - Hua Xie
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
| | - Yiyun Huang
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT 06520-8048, USA.
| | - Hongmei Jia
- Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.
| |
Collapse
|
37
|
Xie L, Zhang L, Hu K, Hanyu M, Zhang Y, Fujinaga M, Minegishi K, Ohkubo T, Nagatsu K, Jiang C, Shimokawa T, Ashisuke K, Okonogi N, Yamada S, Wang F, Wang R, Zhang MR. A 211At-labelled mGluR1 inhibitor induces cancer senescence to elicit long-lasting anti-tumor efficacy. Cell Rep Med 2023; 4:100960. [PMID: 37003259 PMCID: PMC10140459 DOI: 10.1016/j.xcrm.2023.100960] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/01/2022] [Accepted: 02/09/2023] [Indexed: 04/03/2023]
Abstract
Metabotropic glutamate receptor 1 (mGluR1), a key mediator of glutamatergic signaling, is frequently overexpressed in tumor cells and is an attractive drug target for most cancers. Here, we present a targeted radiopharmaceutical therapy strategy that antagonistically recognizes mGluR1 and eradicates mGluR1+ human tumors by harnessing a small-molecule alpha (α)-emitting radiopharmaceutical, 211At-AITM. A single dose of 211At-AITM (2.96 MBq) in mGluR1+ cancers exhibits long-lasting in vivo antitumor efficacy across seven subtypes of four of the most common tumors, namely, breast cancer, pancreatic cancer, melanoma, and colon cancers, with little toxicity. Moreover, complete regression of mGluR1+ breast cancer and pancreatic cancer is observed in approximate 50% of tumor-bearing mice. Mechanistically, the functions of 211At-AITM are uncovered in downregulating mGluR1 oncoprotein and inducing senescence of tumor cells with a reprogrammed senescence-associated secretory phenotype. Our findings suggest α-radiopharmaceutical therapy with 211At-AITM can be a useful strategy for mGluR1+ pan-cancers, regardless of their tissue of origin.
Collapse
Affiliation(s)
- Lin Xie
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan.
| | - Lulu Zhang
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan; Department of Nuclear Medicine, Nanjing First Hospital, Nanjing Medical University, Nanjing 211166, China
| | - Kuan Hu
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan; State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Masayuki Hanyu
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Yiding Zhang
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Masayuki Fujinaga
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Katsuyuki Minegishi
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Takayuki Ohkubo
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Kotaro Nagatsu
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Cuiping Jiang
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan; Department of Nuclear Medicine, Nanjing First Hospital, Nanjing Medical University, Nanjing 211166, China
| | - Takashi Shimokawa
- Department of Charged Particle Therapy Research, Quantum Life and Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Kazuma Ashisuke
- Department of Charged Particle Therapy Research, Quantum Life and Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Noriyuki Okonogi
- Department of Charged Particle Therapy Research, Quantum Life and Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Shigeru Yamada
- Department of Charged Particle Therapy Research, Quantum Life and Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Feng Wang
- Department of Nuclear Medicine, Nanjing First Hospital, Nanjing Medical University, Nanjing 211166, China
| | - Rui Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Ming-Rong Zhang
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan.
| |
Collapse
|
38
|
Li Q, Hu Q, Tang J, Fang Y, Liu C, Liu J, Qi M, Chen Z, Zhang L. Deuterated [ 18F]fluoroethyl tropane analogs as dopamine transporter probes: Synthesis and biological evaluation. Nucl Med Biol 2023; 118-119:108334. [PMID: 37028197 DOI: 10.1016/j.nucmedbio.2023.108334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 03/07/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023]
Abstract
INTRODUCTION The dopamine transporter (DAT) is vitally correlated with Parkinson's disease (PD) and other neurodegenerative diseases. Non-invasive imaging of DAT contributes to early diagnosis and monitoring of related diseases. Recently, we reported a deuterated [18F]fluoroethyl tropane analogue [18F]FECNT-d4 as a potential DAT PET imaging agent. The objective of this work was to extend the investigation by comparing four deuterated [18F]fluoroethyl tropane derivatives ([18F]2a-d) to develop metabolically stable DAT radioligands. METHODS Four fluoroethyl substituted phenyl-tropane compounds 1a-d and deuterated compounds 2a-d were synthesized and their IC50 values to DAT were evaluated. The [18F]fluoroethyl ligands [18F]1a-d and [18F]2a-d were obtained from corresponding labeling precursors by one-step radio-labeling reactions and investigated in terms of lipophilicity and in vitro binding affinity studies. [18F]1d and [18F]2d were then selected for further evaluations by in vivo metabolism study, biodistribution, ex vivo autoradiography, and microPET imaging studies. RESULTS [18F]1a-d and [18F]2a-d were obtained in radiochemical yield of 11-32 % with molar activities of 28-54 GBq/μmol. The 1d and 2d exhibited relatively high affinity to DAT (IC50: 1.9-2.1 nM). Ex vivo autoradiography and microPET studies showed that [18F]2d selectively localized on DAT-rich striatal regions and the specific signal could be blocked by DAT inhibitor. Biodistribution results showed that [18F]2d consistently exhibited a higher ratio of the target to non-target (striatum/cerebellum) than [18F]1d. Furthermore, metabolism study indicated that the in vivo metabolic stability of [18F]2d was superior to that of [18F]1d. CONCLUSION Our findings suggested that the deuterated compound [18F]2d might be a potential probe for DAT PET imaging in the brain.
Collapse
Affiliation(s)
- Qingming Li
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou 221004, China
| | - Qianyue Hu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Jie Tang
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Yi Fang
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Chunyi Liu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Jie Liu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Meihui Qi
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; School of Pharmaceutical Science, Inner Mongolia Medical University, Hohhot 010110, China
| | - Zhengping Chen
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou 221004, China; NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China; School of Pharmaceutical Science, Inner Mongolia Medical University, Hohhot 010110, China.
| | - Ling Zhang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou 221004, China.
| |
Collapse
|
39
|
Cools R, Vermeulen K, Narykina V, Leitao RCF, Bormans G. Radiosynthesis and preclinical evaluation of [ 11C]SNX-ab as an Hsp90α,β isoform-selective PET probe for in vivo brain and tumour imaging. EJNMMI Radiopharm Chem 2023; 8:2. [PMID: 36715827 PMCID: PMC9886718 DOI: 10.1186/s41181-023-00189-0] [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: 11/29/2022] [Accepted: 01/13/2023] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND The molecular chaperone, Hsp90, is a key player in the protein quality control system that maintains homeostasis under cellular stress conditions. It is a homodimer with ATP-dependent activity, and is a prominent member of the chaperone machinery that stabilizes, matures and (re)folds an extensive list of client proteins. Hsp90 occurs as four isoforms, cytosolic Hsp90α and Hsp90β, mitochondrial TRAP1 and Grp94 present in the endoplasmic reticulum. An aberrant role of Hsp90 has been attributed to several cancers and neurodegenerative disorders. Consequently, Hsp90 has emerged as an attractive therapeutic target. However, pan-Hsp90 inhibition often leads to detrimental dose-limiting toxicities. Novel strategies for Hsp90-targeted therapy intend to avoid this by using isoform-specific Hsp90 inhibition. In this respect, the radiosynthesis of carbon-11 labeled SNX-ab was developed and [11C]SNX-ab was evaluated as a Hsp90α,β isoform-selective PET probe, which could potentially allow to quantify in vivo Hsp90α,β expression. RESULTS [11C]SNX-ab was synthesized with excellent radiochemical yields of 45% and high radiochemical purity (> 98%). In vitro autoradiography studies on tissue slices of healthy mouse brain, mouse B16.F10 melanoma and U87 glioblastoma using homologous (SNX-ab, SNX-0723) and heterologous (Onalespib and PU-H71) Hsp90 inhibitors demonstrated only limited reduction of tracer binding, indicating that the binding of [11C]SNX-ab was not fully Hsp90-specific. Similarly, [11C]SNX-ab binding to U87 cells was not efficiently inhibited by Hsp90 inhibitors. Ex vivo biodistribution studies in healthy mice revealed limited brain exposure of [11C]SNX-ab and predominantly hepatobiliary clearance, which was confirmed by in vivo full-body dynamic µPET studies. CONCLUSION Our results suggest that [11C]SNX-ab is not an ideal probe for in vivo visualization and quantification of Hsp90α/β expression levels in tumour and brain. Future research in the development of next-generation Hsp90 isoform-selective PET tracers is warranted to dissect the role played by each isoform towards disease pathology and support the development of subtype-specific Hsp90 therapeutics.
Collapse
Affiliation(s)
- Romy Cools
- grid.5596.f0000 0001 0668 7884Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Koen Vermeulen
- grid.5596.f0000 0001 0668 7884Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium ,grid.8953.70000 0000 9332 3503NURA, Belgian Nuclear Research Centre (SCK CEN), 2400 Mol, Belgium
| | - Valeria Narykina
- grid.511015.1Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000 Leuven, Belgium ,grid.5596.f0000 0001 0668 7884Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Renan C. F. Leitao
- grid.5596.f0000 0001 0668 7884Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Guy Bormans
- grid.5596.f0000 0001 0668 7884Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| |
Collapse
|
40
|
Pees A, Chassé M, Lindberg A, Vasdev N. Recent Developments in Carbon-11 Chemistry and Applications for First-In-Human PET Studies. Molecules 2023; 28:molecules28030931. [PMID: 36770596 PMCID: PMC9920299 DOI: 10.3390/molecules28030931] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 01/19/2023] Open
Abstract
Positron emission tomography (PET) is a molecular imaging technique that makes use of radiolabelled molecules for in vivo evaluation. Carbon-11 is a frequently used radionuclide for the labelling of small molecule PET tracers and can be incorporated into organic molecules without changing their physicochemical properties. While the short half-life of carbon-11 (11C; t½ = 20.4 min) offers other advantages for imaging including multiple PET scans in the same subject on the same day, its use is limited to facilities that have an on-site cyclotron, and the radiochemical transformations are consequently more restrictive. Many researchers have embraced this challenge by discovering novel carbon-11 radiolabelling methodologies to broaden the synthetic versatility of this radionuclide. This review presents new carbon-11 building blocks and radiochemical transformations as well as PET tracers that have advanced to first-in-human studies over the past five years.
Collapse
Affiliation(s)
- Anna Pees
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, ON M5T 1R8, Canada
| | - Melissa Chassé
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, ON M5T 1R8, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Anton Lindberg
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, ON M5T 1R8, Canada
| | - Neil Vasdev
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, ON M5T 1R8, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON M5T 1R8, Canada
- Correspondence:
| |
Collapse
|
41
|
Liu T, Li Y, Wang Y, Yan XX, Dai J, Cui M. Discovery and evaluation of aza-fused tricyclic derivatives for detection of Tau pathology in Alzheimer's disease. Eur J Med Chem 2023; 246:114991. [PMID: 36493618 DOI: 10.1016/j.ejmech.2022.114991] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 11/09/2022] [Accepted: 11/28/2022] [Indexed: 12/03/2022]
Abstract
For various neurodegenerative diseases, including Alzheimer's disease (AD), the abnormal aggregation of Tau is not only the predominant contributing factor but also a major biomarker for disease diagnosis. In this study, a series of aza-fused tricyclic derivatives were designed and synthesized. By changing the position and number of nitrogen atoms on the fused tricyclic core, the imidazonaphthyridine scaffold was screened and reported for the first time which could potentially detect Tau aggregates. Through a series of in vitro and in vivo biological evaluations, probe [125I]5 possessed exceptional binding affinity (IC50 = 1.63 nM) to neurofibrillary tangles in the AD brain, high selectivity over Aβ plaques (23.4-fold), clean off-target profile to monoamine oxidase A/B (MAO-A/B), and suitable pharmacokinetics (initial brain uptake = 3.22% ID/g).
Collapse
Affiliation(s)
- Tianqing Liu
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Yuying Li
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Yan Wang
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, 410013, China
| | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, 410013, China
| | - Jiapei Dai
- Wuhan Institute for Neuroscience and Neuroengineering, South-Central Minzu University, Wuhan, 430074, China
| | - Mengchao Cui
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China; Center for Advanced Materials Research, Beijing Normal University, Zhuhai, 519087, China.
| |
Collapse
|
42
|
ImmunoPET Directed to the Brain: A New Tool for Preclinical and Clinical Neuroscience. Biomolecules 2023; 13:biom13010164. [PMID: 36671549 PMCID: PMC9855881 DOI: 10.3390/biom13010164] [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: 12/21/2022] [Revised: 01/08/2023] [Accepted: 01/10/2023] [Indexed: 01/14/2023] Open
Abstract
Immuno-positron emission tomography (immunoPET) is a non-invasive in vivo imaging method based on tracking and quantifying radiolabeled monoclonal antibodies (mAbs) and other related molecules, such as antibody fragments, nanobodies, or affibodies. However, the success of immunoPET in neuroimaging is limited because intact antibodies cannot penetrate the blood-brain barrier (BBB). In neuro-oncology, immunoPET has been successfully applied to brain tumors because of the compromised BBB. Different strategies, such as changes in antibody properties, use of physiological mechanisms in the BBB, or induced changes to BBB permeability, have been developed to deliver antibodies to the brain. These approaches have recently started to be applied in preclinical central nervous system PET studies. Therefore, immunoPET could be a new approach for developing more specific PET probes directed to different brain targets.
Collapse
|
43
|
Huang G, Qiu Y, Bi L, Wei H, Li G, Li Z, Ye P, Yang M, Shen Y, Liu H, Wang L, Jin H. PET Imaging of P2X7 Receptor (P2X7R) for Neuroinflammation with Improved Radiosynthesis of Tracer [18F]4A in Mice and Non-human Primates. ACS Chem Neurosci 2022; 13:3464-3476. [PMID: 36441909 DOI: 10.1021/acschemneuro.2c00506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The P2X7 receptor (P2X7R) is a key neuroinflammation target in a variety of neurodegenerative diseases. Improved radiosynthesis was developed according to the previously reported P2X7R antagonist GSK1482160. Biodistribution, radiometabolite, and dynamic positron emission tomography/computed tomography-magnetic resonance imaging (PET/CT-MRI) of the lipopolysaccharide (LPS) rat model and the transgenic mouse model of Alzheimer's disease (AD) revealed a stable, low uptake of [18F]4A in the brain of healthy rats but a higher standardized uptake value ratio (SUVR) in LPS-treated rats (1.316 ± 0.062, n = 3) than in sham (1.093 ± 0.029, n = 3). There were higher area under curves (AUCs) in the neocortex (25.12 ± 1.11 vs 18.94 ± 1.47), hippocampus (22.50 ± 3.41 vs 15.90 ± 1.59), and basal ganglia (22.26 ± 0.81 vs 15.32 ± 1.76) of AD mice (n = 3) than the controls (n = 3) (p < 0.05). Furthermore, 50 min dynamic PET in healthy nonhuman primates (NHPs) indicated [18F]4A could penetrate the blood-brain barrier (BBB). In conclusion, [18F]4A from this study is a potent P2X7R PET tracer that warrants further neuroinflammation quantification in human studies.
Collapse
Affiliation(s)
- Guolong Huang
- Guangdong Provincial Key Laboratory of Biomedical Imaging, Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai519000, Guangdong, China
| | - Yifan Qiu
- Guangdong Provincial Key Laboratory of Biomedical Imaging, Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai519000, Guangdong, China
| | - Lei Bi
- Guangdong Provincial Key Laboratory of Biomedical Imaging, Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai519000, Guangdong, China
| | - Huiyi Wei
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou510630, China
| | - Guocong Li
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou510630, China
| | - Zhijun Li
- Guangdong Provincial Key Laboratory of Biomedical Imaging, Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai519000, Guangdong, China
| | - Peizhen Ye
- Guangdong Provincial Key Laboratory of Biomedical Imaging, Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai519000, Guangdong, China
| | - Min Yang
- Guangdong Provincial Key Laboratory of Biomedical Imaging, Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai519000, Guangdong, China
| | - Yanfang Shen
- Guangdong Provincial Key Laboratory of Biomedical Imaging, Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai519000, Guangdong, China
| | - Hao Liu
- Guangdong Provincial Key Laboratory of Biomedical Imaging, Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai519000, Guangdong, China
| | - Lu Wang
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou510630, China
| | - Hongjun Jin
- Guangdong Provincial Key Laboratory of Biomedical Imaging, Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai519000, Guangdong, China
| |
Collapse
|
44
|
Nuez-Martínez M, Queralt-Martín M, Muñoz-Juan A, Aguilella VM, Laromaine A, Teixidor F, Viñas C, Pinto CG, Pinheiro T, Guerreiro JF, Mendes F, Roma-Rodrigues C, Baptista PV, Fernandes AR, Valic S, Marques F. Boron clusters (ferrabisdicarbollides) shaping the future as radiosensitizers for multimodal (chemo/radio/PBFR) therapy of glioblastoma. J Mater Chem B 2022; 10:9794-9815. [PMID: 36373493 DOI: 10.1039/d2tb01818g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Glioblastoma multiforme (GBM) is the most common and fatal primary brain tumor, and is highly resistant to conventional radiotherapy and chemotherapy. Therefore, the development of multidrug resistance and tumor recurrence are frequent. Given the poor survival with the current treatments, new therapeutic strategies are urgently needed. Radiotherapy (RT) is a common cancer treatment modality for GBM. However, there is still a need to improve RT efficiency, while reducing the severe side effects. Radiosensitizers can enhance the killing effect on tumor cells with less side effects on healthy tissues. Herein, we present our pioneering study on the highly stable and amphiphilic metallacarboranes, ferrabis(dicarbollides) ([o-FESAN]- and [8,8'-I2-o-FESAN]-), as potential radiosensitizers for GBM radiotherapy. We propose radiation methodologies that utilize secondary radiation emissions from iodine and iron, using ferrabis(dicarbollides) as iodine/iron donors, aiming to achieve a greater therapeutic effect than that of a conventional radiotherapy. As a proof-of-concept, we show that using 2D and 3D models of U87 cells, the cellular viability and survival were reduced using this treatment approach. We also tested for the first time the proton boron fusion reaction (PBFR) with ferrabis(dicarbollides), taking advantage of their high boron (11B) content. The results from the cellular damage response obtained suggest that proton boron fusion radiation therapy, when combined with boron-rich compounds, is a promising modality to fight against resistant tumors. Although these results are encouraging, more developments are needed to further explore ferrabis(dicarbollides) as radiosensitizers towards a positive impact on the therapeutic strategies for GBM.
Collapse
Affiliation(s)
- Miquel Nuez-Martínez
- Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Campus Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
| | - María Queralt-Martín
- Laboratory of Molecular Biophysics, Department of Physics, Universitat Jaume I, 12071 Castelló, Spain
| | - Amanda Muñoz-Juan
- Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Campus Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
| | - Vicente M Aguilella
- Laboratory of Molecular Biophysics, Department of Physics, Universitat Jaume I, 12071 Castelló, Spain
| | - Anna Laromaine
- Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Campus Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
| | - Francesc Teixidor
- Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Campus Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
| | - Clara Viñas
- Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Campus Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
| | - Catarina G Pinto
- Centro de Ciências e Tecnologias Nucleares and Departamento de Engenharia e Ciências Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela LRS, Portugal.
| | - Teresa Pinheiro
- iBB - Instituto de Bioengenharia e Biociências, Departamento de Engenharia e Ciências Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - Joana F Guerreiro
- Centro de Ciências e Tecnologias Nucleares and Departamento de Engenharia e Ciências Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela LRS, Portugal.
| | - Filipa Mendes
- Centro de Ciências e Tecnologias Nucleares and Departamento de Engenharia e Ciências Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela LRS, Portugal.
| | - Catarina Roma-Rodrigues
- UCIBIO - Applied Molecular Biosciences Unit, Department of Life Sciences, NOVA School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal.,Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal
| | - Pedro V Baptista
- UCIBIO - Applied Molecular Biosciences Unit, Department of Life Sciences, NOVA School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal.,Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal
| | - Alexandra R Fernandes
- UCIBIO - Applied Molecular Biosciences Unit, Department of Life Sciences, NOVA School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal.,Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal
| | - Srecko Valic
- Ruđer Bošković Institute, Bijenička 54, HR-10000 Zagreb, Croatia
| | - Fernanda Marques
- Centro de Ciências e Tecnologias Nucleares and Departamento de Engenharia e Ciências Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela LRS, Portugal.
| |
Collapse
|
45
|
Ahmed H, Zheng MQ, Smart K, Fang H, Zhang L, Emery PR, Gao H, Ropchan J, Haider A, Tamagnan G, Carson RE, Ametamey SM, Huang Y. Evaluation of ( rac)-, ( R)-, and ( S)- 18F-OF-NB1 for Imaging GluN2B Subunit-Containing N-Methyl-d-Aspartate Receptors in Nonhuman Primates. J Nucl Med 2022; 63:1912-1918. [PMID: 35710735 PMCID: PMC9730915 DOI: 10.2967/jnumed.122.263977] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/07/2022] [Indexed: 01/11/2023] Open
Abstract
Despite 2 decades of research, no N-methyl-d-aspartate (NMDA) glutamate receptor (GluN) subtype 2B (GluN1/2B) radioligand is yet clinically validated. Previously, we reported on (rac)-18F-OF-NB1 as a promising GluN1/2B PET probe in rodents and its successful application for the visualization of GluN2B-containing NMDA receptors in postmortem brain tissues of patients with amyotrophic lateral sclerosis. In the current work, we report on the in vivo characterization of (rac)-, (R)-, and (S)-18F-OF-NB1 in nonhuman primates. Methods: PET scans were performed on rhesus monkeys. Plasma profiling was used to obtain the arterial input function. Regional brain time-activity curves were generated and fitted with the 1- and 2-tissue-compartment models and the multilinear analysis 1 method, and the corresponding regional volumes of distribution were calculated. Blocking studies with the GluN1/2B ligand Co 101244 (0.25 mg/kg) were performed for the enantiopure radiotracers. Receptor occupancy, nonspecific volume of distribution, and regional binding potential (BP ND) were obtained. Potential off-target binding toward σ1 receptors was assessed for (S)-18F-OF-NB1 using the σ1 receptor ligand FTC-146. Results: Free plasma fraction was moderate, ranging from 12% to 16%. All radiotracers showed high and heterogeneous brain uptake, with the highest levels in the cortex. (R)-18F-OF-NB1 showed the highest uptake and slowest washout kinetics of all tracers. The 1-tissue-compartment model and multilinear analysis 1 method fitted the regional time-activity curves well for all tracers and produced reliable regional volumes of distribution, which were higher for (R)- than (S)-18F-OF-NB1. Receptor occupancy by Co 101244 was 85% and 96% for (S)-18F-OF-NB1 and (R)-18F-OF-NB1, respectively. Pretreatment with FTC-146 at both a low (0.027 mg/kg) and high (0.125 mg/kg) dose led to a similar reduction (48% and 49%, respectively) in specific binding of (S)-18F-OF-NB1. Further, pretreatment with both Co 101244 and FTC-146 did not result in a further reduction in specific binding compared with Co 101244 alone in the same monkey (82% vs. 81%, respectively). Regional BP ND values ranged from 1.3 in the semiovale to 3.4 in the cingulate cortex for (S)-18F-OF-NB1. Conclusion: Both (R)- and (S)-18F-OF-NB1 exhibited high binding specificity to GluN2B subunit-containing NMDA receptors. The fast washout kinetics, good regional BP ND values, and high plasma free fraction render (S)-18F-OF-NB1 an attractive radiotracer for clinical translation.
Collapse
Affiliation(s)
- Hazem Ahmed
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
- PET Center, Yale University, New Haven, Connecticut; and
| | | | - Kelly Smart
- PET Center, Yale University, New Haven, Connecticut; and
| | - Hanyi Fang
- PET Center, Yale University, New Haven, Connecticut; and
- Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Li Zhang
- PET Center, Yale University, New Haven, Connecticut; and
| | - Paul R Emery
- PET Center, Yale University, New Haven, Connecticut; and
| | - Hong Gao
- PET Center, Yale University, New Haven, Connecticut; and
| | - Jim Ropchan
- PET Center, Yale University, New Haven, Connecticut; and
| | - Ahmed Haider
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
| | | | | | - Simon M Ametamey
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland;
| | - Yiyun Huang
- PET Center, Yale University, New Haven, Connecticut; and
| |
Collapse
|
46
|
Mairinger S, Hernández-Lozano I, Zeitlinger M, Ehrhardt C, Langer O. Nuclear medicine imaging methods as novel tools in the assessment of pulmonary drug disposition. Expert Opin Drug Deliv 2022; 19:1561-1575. [PMID: 36255136 DOI: 10.1080/17425247.2022.2137143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
INTRODUCTION Drugs for the treatment of respiratory diseases are commonly administered by oral inhalation. Yet surprisingly little is known about the pulmonary pharmacokinetics of inhaled molecules. Nuclear medicine imaging techniques (i.e. planar gamma scintigraphy, single-photon emission computed tomography [SPECT] and positron emission tomography [PET]) enable the noninvasive dynamic measurement of the lung concentrations of radiolabeled drugs or drug formulations. This review discusses the potential of nuclear medicine imaging techniques in inhalation biopharmaceutical research. AREAS COVERED (i) Planar gamma scintigraphy studies with radiolabeled inhalation formulations to assess initial pulmonary drug deposition; (ii) imaging studies with radiolabeled drugs to assess their intrapulmonary pharmacokinetics; (iii) receptor occupancy studies to quantify the pharmacodynamic effect of inhaled drugs. EXPERT OPINION Imaging techniques hold potential to bridge the knowledge gap between animal models and humans with respect to the pulmonary disposition of inhaled drugs. However, beyond the mere assessment of the initial lung deposition of inhaled formulations with planar gamma scintigraphy, imaging techniques have rarely been employed in pulmonary drug development. This may be related to several technical challenges encountered with such studies. Considering the wealth of information that can be obtained with imaging studies their use in inhalation biopharmaceutics should be further investigated.
Collapse
Affiliation(s)
- Severin Mairinger
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | | | - Markus Zeitlinger
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Carsten Ehrhardt
- School of Pharmacy and Pharmaceutical Sciences and Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Oliver Langer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
47
|
Impact of Cytochrome Induction or Inhibition on the Plasma and Brain Kinetics of [ 11C]metoclopramide, a PET Probe for P-Glycoprotein Function at the Blood-Brain Barrier. Pharmaceutics 2022; 14:pharmaceutics14122650. [PMID: 36559144 PMCID: PMC9785688 DOI: 10.3390/pharmaceutics14122650] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 11/23/2022] [Accepted: 11/26/2022] [Indexed: 12/03/2022] Open
Abstract
[11C]metoclopramide PET imaging provides a sensitive and translational tool to explore P-glycoprotein (P-gp) function at the blood-brain barrier (BBB). Patients with neurological diseases are often treated with cytochrome (CYP) modulators which may impact the plasma and brain kinetics of [11C]metoclopramide. The impact of the CYP inducer carbamazepine or the CYP inhibitor ritonavir on the brain and plasma kinetics of [11C]metoclopramide was investigated in rats. Data obtained in a control group were compared with groups that were either orally pretreated with carbamazepine (45 mg/kg twice a day for 7 days before PET) or ritonavir (20 mg/kg, 3 h before PET) (n = 4 per condition). Kinetic modelling was performed to estimate the brain penetration (VT) of [11C]metoclopramide. CYP induction or inhibition had negligible impact on the plasma kinetics and metabolism of [11C]metoclopramide. Moreover, carbamazepine neither impacted the brain kinetics nor VT of [11C]metoclopramide (p > 0.05). However, ritonavir significantly increased VT (p < 0.001), apparently behaving as an inhibitor of P-gp at the BBB. Our data suggest that treatment with potent CYP inducers such as carbamazepine does not bias the estimation of P-gp function at the BBB with [11C]metoclopramide PET. This supports further use of [11C]metoclopramide for studies in animals and patients treated with CYP inducers.
Collapse
|
48
|
Koike T. Development of Specific PET Tracers for Central Nervous System Drug Targets. J SYN ORG CHEM JPN 2022. [DOI: 10.5059/yukigoseikyokaishi.80.1044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Tatsuki Koike
- Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited
| |
Collapse
|
49
|
Cheng R, Fujinaga M, Yang J, Rong J, Haider A, Ogasawara D, Van RS, Shao T, Chen Z, Zhang X, Calderon Leon ER, Zhang Y, Mori W, Kumata K, Yamasaki T, Xie L, Sun S, Wang L, Ran C, Shao Y, Cravatt B, Josephson L, Zhang MR, Liang SH. A novel monoacylglycerol lipase-targeted 18F-labeled probe for positron emission tomography imaging of brown adipose tissue in the energy network. Acta Pharmacol Sin 2022; 43:3002-3010. [PMID: 35513432 PMCID: PMC9622914 DOI: 10.1038/s41401-022-00912-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 04/13/2022] [Indexed: 11/09/2022] Open
Abstract
Monoacylglycerol lipase (MAGL) constitutes a serine hydrolase that orchestrates endocannabinoid homeostasis and exerts its function by catalyzing the degradation of 2-arachidonoylglycerol (2-AG) to arachidonic acid (AA). As such, selective inhibition of MAGL represents a potential therapeutic and diagnostic approach to various pathologies including neurodegenerative disorders, metabolic diseases and cancers. Based on a unique 4-piperidinyl azetidine diamide scaffold, we developed a reversible and peripheral-specific radiofluorinated MAGL PET ligand [18F]FEPAD. Pharmacokinetics and binding studies on [18F]FEPAD revealed its outstanding specificity and selectivity towards MAGL in brown adipose tissue (BAT) - a tissue that is known to be metabolically active. We employed [18F]FEPAD in PET studies to assess the abundancy of MAGL in BAT deposits of mice and found a remarkable degree of specific tracer binding in the BAT, which was confirmed by post-mortem tissue analysis. Given the negative regulation of endocannabinoids on the metabolic BAT activity, our study supports the concept that dysregulation of MAGL is likely linked to metabolic disorders. Further, we now provide a suitable imaging tool that allows non-invasive assessment of MAGL in BAT deposits, thereby paving the way for detailed mechanistic studies on the role of BAT in endocannabinoid system (ECS)-related pathologies.
Collapse
Affiliation(s)
- Ran Cheng
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
- School of Medical Imaging, Tianjin Medical University, Tianjin, 300203, China
| | - Masayuki Fujinaga
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Jing Yang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02125, USA
| | - Jian Rong
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Ahmed Haider
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Daisuke Ogasawara
- The Skaggs Institute for Chemical Biology and Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Richard S Van
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Tuo Shao
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Zhen Chen
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Xiaofei Zhang
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Erick R Calderon Leon
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Yiding Zhang
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Wakana Mori
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Katsushi Kumata
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Tomoteru Yamasaki
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Lin Xie
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Shaofa Sun
- Hubei Collaborative Innovation Centre for Non-power Nuclear Technology, College of Nuclear Technology & Chemistry and Biology, Hubei University of Science and Technology, Xianning, Hubei Province, 437100, China
| | - Lu Wang
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Chongzhao Ran
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02125, USA
| | - Yihan Shao
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Benjamin Cravatt
- The Skaggs Institute for Chemical Biology and Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Lee Josephson
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA
| | - Ming-Rong Zhang
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan.
| | - Steven H Liang
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA.
| |
Collapse
|
50
|
Kallinen A, Kassiou M. Tracer development for PET imaging of proteinopathies. Nucl Med Biol 2022; 114-115:108-120. [PMID: 35487833 DOI: 10.1016/j.nucmedbio.2022.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 02/17/2022] [Accepted: 04/04/2022] [Indexed: 12/27/2022]
Abstract
This review outlines small molecule radiotracers developed for positron emission tomography (PET) imaging of proteinopathies, neurodegenerative diseases characterised by accumulation of malformed proteins, over the last two decades with the focus on radioligands that have progressed to clinical studies. Introduction provides a short summary of proteinopathy targets used for PET imaging, including vastly studied proteins Aβ and tau and emerging α-synuclein. In the main section, clinically relevant Aβ and tau radioligand classes and their properties are discussed, including an overview of lead compounds and radioligand candidates studied as α-synuclein imaging agents in the early discovery and preclinical development phase. Lastly, the specific challenges and future directions in proteinopathy radioligand development are summarized.
Collapse
Affiliation(s)
- Annukka Kallinen
- Garvan Institute of Medical Research, 384 Victoria St, NSW 2010, Australia.
| | - Michael Kassiou
- School of Chemistry, The University of Sydney, NSW 2006, Australia
| |
Collapse
|