1
|
Cools R, Kerkhofs K, Leitao RCF, Bormans G. Preclinical Evaluation of Novel PET Probes for Dementia. Semin Nucl Med 2023; 53:599-629. [PMID: 37149435 DOI: 10.1053/j.semnuclmed.2023.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 03/24/2023] [Indexed: 05/08/2023]
Abstract
The development of novel PET imaging agents that selectively bind specific dementia-related targets can contribute significantly to accurate, differential and early diagnosis of dementia causing diseases and support the development of therapeutic agents. Consequently, in recent years there has been a growing body of literature describing the development and evaluation of potential new promising PET tracers for dementia. This review article provides a comprehensive overview of novel dementia PET probes under development, classified by their target, and pinpoints their preclinical evaluation pathway, typically involving in silico, in vitro and ex/in vivo evaluation. Specific target-associated challenges and pitfalls, requiring extensive and well-designed preclinical experimental evaluation assays to enable successful clinical translation and avoid shortcomings observed for previously developed 'well-established' dementia PET tracers are highlighted in this review.
Collapse
Affiliation(s)
- Romy Cools
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Kobe Kerkhofs
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium; NURA, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium
| | - Renan C F Leitao
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Guy Bormans
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium.
| |
Collapse
|
2
|
Titi A, Touzani R, Moliterni A, Hadda TB, Messali M, Benabbes R, Berredjem M, Bouzina A, Al-Zaqri N, Taleb M, Zarrouk A, Warad I. Synthesis, structural, biocomputational modeling and antifungal activity of novel armed pyrazoles. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
3
|
Kaur J, Bhardwaj A, Wuest F. Fluorine-18 Labelled Radioligands for PET Imaging of Cyclooxygenase-2. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27123722. [PMID: 35744851 PMCID: PMC9227202 DOI: 10.3390/molecules27123722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 06/03/2022] [Accepted: 06/07/2022] [Indexed: 11/18/2022]
Abstract
Molecular imaging probes enable the early and accurate detection of disease-specific biomarkers and facilitate personalized treatment of many chronic diseases, including cancer. Among current clinically used functional imaging modalities, positron emission tomography (PET) plays a significant role in cancer detection and in monitoring the response to therapeutic interventions. Several preclinical and clinical studies have demonstrated the crucial involvement of cyclooxygenase-2 (COX-2) isozyme in cancer development and progression, making COX-2 a promising cancer biomarker. A variety of COX-2-targeting PET radioligands has been developed based on anti-inflammatory drugs and selective COX-2 inhibitors. However, many of those suffer from non-specific binding and insufficient metabolic stability. This article highlights examples of COX-2-targeting PET radioligands labelled with the short-lived positron emitter 18F, including radiosynthesis and PET imaging studies published in the last decade (2012–2021).
Collapse
Affiliation(s)
- Jatinder Kaur
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada;
- Correspondence: (J.K.); (F.W.)
| | - Atul Bhardwaj
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada;
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB T6G 1Z2, Canada
| | - Frank Wuest
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada;
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB T6G 1Z2, Canada
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 1Z2, Canada
- Correspondence: (J.K.); (F.W.)
| |
Collapse
|
4
|
Nutma E, Ceyzériat K, Amor S, Tsartsalis S, Millet P, Owen DR, Papadopoulos V, Tournier BB. Cellular sources of TSPO expression in healthy and diseased brain. Eur J Nucl Med Mol Imaging 2021; 49:146-163. [PMID: 33433698 PMCID: PMC8712293 DOI: 10.1007/s00259-020-05166-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 12/13/2020] [Indexed: 12/11/2022]
Abstract
The 18 kDa translocator protein (TSPO) is a highly conserved protein located in the outer mitochondrial membrane. TSPO binding, as measured with positron emission tomography (PET), is considered an in vivo marker of neuroinflammation. Indeed, TSPO expression is altered in neurodegenerative, neuroinflammatory, and neuropsychiatric diseases. In PET studies, the TSPO signal is often viewed as a marker of microglial cell activity. However, there is little evidence in support of a microglia-specific TSPO expression. This review describes the cellular sources and functions of TSPO in animal models of disease and human studies, in health, and in central nervous system diseases. A discussion of methods of analysis and of quantification of TSPO is also presented. Overall, it appears that the alterations of TSPO binding, their cellular underpinnings, and the functional significance of such alterations depend on many factors, notably the pathology or the animal model under study, the disease stage, and the involved brain regions. Thus, further studies are needed to fully determine how changes in TSPO binding occur at the cellular level with the ultimate goal of revealing potential therapeutic pathways.
Collapse
Affiliation(s)
- Erik Nutma
- Department of Pathology, Amsterdam UMC, VUmc, Amsterdam, The Netherlands
| | - Kelly Ceyzériat
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland
- Division of Nuclear medicine and Molecular Imaging, University Hospitals of Geneva, Geneva, Switzerland
- Division of Radiation Oncology, Department of Oncology, University Hospitals of Geneva, Geneva, Switzerland
| | - Sandra Amor
- Department of Pathology, Amsterdam UMC, VUmc, Amsterdam, The Netherlands
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine & Dentistry, Queen Mary University of London, London, UK
| | - Stergios Tsartsalis
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Philippe Millet
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland
- Department of Psychiatry, University of Geneva, Geneva, Switzerland
| | - David R Owen
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Vassilios Papadopoulos
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Benjamin B Tournier
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland.
- Department of Psychiatry, University of Geneva, Geneva, Switzerland.
| |
Collapse
|
5
|
Preliminary Assessment of the Anti-inflammatory Activity of New Structural Honokiol Analogs with a 4'- O-(2-Fluoroethyl) Moiety and the Potential of Their 18F-Labeled Derivatives for Neuroinflammation Imaging. Molecules 2021; 26:molecules26216630. [PMID: 34771039 PMCID: PMC8587714 DOI: 10.3390/molecules26216630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/24/2021] [Accepted: 10/28/2021] [Indexed: 01/31/2023] Open
Abstract
Neolignans honokiol and 4′-O-methylhonokiol (MH) and their derivatives have pronounced anti-inflammatory activity, as evidenced by numerous pharmacological studies. Literature data suggested that cyclooxygenase type 2 (COX-2) may be a target for these compounds in vitro and in vivo. Recent studies of [11C]MPbP (4′-[11C]methoxy-5-propyl-1,1′-biphenyl-2-ol) biodistribution in LPS (lipopolysaccharide)-treated rats have confirmed the high potential of MH derivatives for imaging neuroinflammation. Here, we report the synthesis of four structural analogs of honokiol, of which 4′-(2-fluoroethoxy)-2-hydroxy-5-propyl-1, 1′-biphenyl (F-IV) was selected for labeling with fluorine-18 (T1/2 = 109.8 min) due to its high anti-inflammatory activity confirmed by enzyme immunoassays (EIA) and neuromorphological studies. The high inhibitory potency of F-IV to COX-2 and its moderate lipophilicity and chemical stability are favorable factors for the preliminary evaluation of the radioligand [18F]F-IV in a rodent model of neuroinflammation. [18F]F-IV was prepared with good radiochemical yield and high molar activity and radiochemical purity by 18F-fluoroethylation of the precursor with Boc-protecting group (15) with [18F]2-fluoro-1-bromoethane ([18F]FEB). Ex vivo biodistribution studies revealed a small to moderate increase in radioligand uptake in the brain and peripheral organs of LPS-induced rats compared to control animals. Pretreatment with celecoxib resulted in significant blocking of radioactivity uptake in the brain (pons and medulla), heart, lungs, and kidneys, indicating that [18F]F-IV is likely to specifically bind to COX-2 in a rat model of neuroinflammation. However, in comparison with [11C]MPbP, the new radioligand showed decreased brain uptake in LPS rats and high retention in the blood pool, which apparently could be explained by its high plasma protein binding. We believe that the structure of [18F]F-IV can be optimized by replacing the substituents in the biphenyl core to eliminate these disadvantages and develop new radioligands for imaging activated microglia.
Collapse
|
6
|
Zhou R, Ji B, Kong Y, Qin L, Ren W, Guan Y, Ni R. PET Imaging of Neuroinflammation in Alzheimer's Disease. Front Immunol 2021; 12:739130. [PMID: 34603323 PMCID: PMC8481830 DOI: 10.3389/fimmu.2021.739130] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Accepted: 08/27/2021] [Indexed: 12/15/2022] Open
Abstract
Neuroinflammation play an important role in Alzheimer's disease pathogenesis. Advances in molecular imaging using positron emission tomography have provided insights into the time course of neuroinflammation and its relation with Alzheimer's disease central pathologies in patients and in animal disease models. Recent single-cell sequencing and transcriptomics indicate dynamic disease-associated microglia and astrocyte profiles in Alzheimer's disease. Mitochondrial 18-kDa translocator protein is the most widely investigated target for neuroinflammation imaging. New generation of translocator protein tracers with improved performance have been developed and evaluated along with tau and amyloid imaging for assessing the disease progression in Alzheimer's disease continuum. Given that translocator protein is not exclusively expressed in glia, alternative targets are under rapid development, such as monoamine oxidase B, matrix metalloproteinases, colony-stimulating factor 1 receptor, imidazoline-2 binding sites, cyclooxygenase, cannabinoid-2 receptor, purinergic P2X7 receptor, P2Y12 receptor, the fractalkine receptor, triggering receptor expressed on myeloid cells 2, and receptor for advanced glycation end products. Promising targets should demonstrate a higher specificity for cellular locations with exclusive expression in microglia or astrocyte and activation status (pro- or anti-inflammatory) with highly specific ligand to enable in vivo brain imaging. In this review, we summarised recent advances in the development of neuroinflammation imaging tracers and provided an outlook for promising targets in the future.
Collapse
Affiliation(s)
- Rong Zhou
- Department of Nephrology, Yangpu Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Bin Ji
- Department of Radiopharmacy and Molecular Imaging, School of Pharmacy, Fudan University, Shanghai, China
| | - Yanyan Kong
- Positron Emission Tomography (PET) Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Limei Qin
- Inner Mongolia Baicaotang Qin Chinese Mongolia Hospital, Hohhot, China
| | - Wuwei Ren
- School of Information Science and Technology, Shanghaitech University, Shanghai, China
| | - Yihui Guan
- Positron Emission Tomography (PET) Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Ruiqing Ni
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Institute for Biomedical Engineering, University of Zurich & Eidgenössische Technische Hochschule Zürich (ETH Zurich), Zurich, Switzerland
| |
Collapse
|
7
|
Prabhakaran J, Molotkov A, Mintz A, Mann JJ. Progress in PET Imaging of Neuroinflammation Targeting COX-2 Enzyme. Molecules 2021; 26:molecules26113208. [PMID: 34071951 PMCID: PMC8198977 DOI: 10.3390/molecules26113208] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/12/2021] [Accepted: 05/24/2021] [Indexed: 01/01/2023] Open
Abstract
Neuroinflammation and cyclooxygenase-2 (COX-2) upregulation are associated with the pathogenesis of degenerative brain diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), epilepsy, and a response to traumatic brain injury (TBI) or stroke. COX-2 is also induced in acute pain, depression, schizophrenia, various cancers, arthritis and in acute allograft rejection. Positron emission tomography (PET) imaging allows for the direct measurement of in vivo COX-2 upregulation and thereby enables disease staging, therapy evaluation and aid quantifying target occupancy of novel nonsteroidal anti-inflammatory drugs or NSAIDs. Thus far, no clinically useful radioligand is established for monitoring COX-2 induction in brain diseases due to the delay in identifying qualified COX-2-selective inhibitors entering the brain. This review examines radiolabeled COX-2 inhibitors reported in the past decade and identifies the most promising radioligands for development as clinically useful PET radioligands. Among the radioligands reported so far, the three tracers that show potential for clinical translation are, [11CTMI], [11C]MC1 and [18F]MTP. These radioligands demonstrated BBB permeablity and in vivo binding to constitutive COX-2 in the brain or induced COX-2 during neuroinflammation.
Collapse
Affiliation(s)
- Jaya Prabhakaran
- Department of Psychiatry, Columbia University Medical Center, New York, NY 10032, USA;
- Correspondence:
| | - Andrei Molotkov
- Department of Radiology, Columbia University Medical Center, New York, NY 10032, USA; (A.M.); (A.M.)
| | - Akiva Mintz
- Department of Radiology, Columbia University Medical Center, New York, NY 10032, USA; (A.M.); (A.M.)
- Area Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY 10032, USA
| | - J. John Mann
- Department of Psychiatry, Columbia University Medical Center, New York, NY 10032, USA;
- Area Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY 10032, USA
| |
Collapse
|