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Ye Z, Lu X, Zhu M, Bi L, Yang F, Zhou B, Xu D, Yao L. STING-Targeted PET Imaging for Specific Detection and Therapeutic Monitoring of Myocarditis. Mol Pharm 2024; 21:2865-2877. [PMID: 38666508 DOI: 10.1021/acs.molpharmaceut.4c00024] [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: 06/04/2024]
Abstract
Imaging strategies for the specific detection and therapeutic monitoring of myocarditis are still lacking. Stimulator of interferon genes (STING) is a signal transduction molecule involved in an innate immune response. Here, we evaluated the feasibility of the recently developed STING-targeted radiotracer [18F]FBTA for positron emission tomography (PET) imaging to detect myocardial inflammation and monitor treatment in myocarditis mice. [18F]FBTA-PET imaging was performed in myocarditis mice and normal mice to verify the specificity of [18F]FBTA for the diagnosis of myocarditis. We also performed PET imaging in mice with myocarditis treated to verify the ability of [18F]FBTA in therapeutic monitoring. The expression of STING and inflammatory cell types was confirmed by flow cytometry and immunohistochemistry. [18F]FDG-PET imaging of myocarditis was used as a contrast. [18F]FBTA-PET imaging showed that the average radioactive uptake was significantly higher in the hearts of the myocarditis group than in the control group. STING was highly overexpressed in cardiac inflammatory cells, including macrophages, dendritic cells (DCs), and T cells. However, there was no significant difference in cardiac radiotracer uptake of [18F]FDG between the myocarditis group and the control group. Moreover, cardiac uptake of [18F]FBTA was significantly reduced in cyclosporin A-treated myocarditis mice and myocardial STING expression was also significantly reduced after the treatment. Overall, we showed that a STING-targeted PET tracer [18F]FBTA can be used to monitor changes in the inflammatory microenvironment in myocarditis. Besides, [18F]FBTA-PET is also suitable for real-time monitoring of myocarditis treatment, representing a promising diagnostic and therapeutic monitoring approach for myocarditis.
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Affiliation(s)
- Zhou Ye
- Department of Emergency Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Xin Lu
- Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Department of Nuclear Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Manman Zhu
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Lei Bi
- Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Fan Yang
- Department of Pediatrics, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Department of Nuclear Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Bin Zhou
- Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Center of Cerebrovascular Disease, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Duo Xu
- Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Department of Nuclear Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- Guangdong-Hong Kong-Macao University Joint Laboratory of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai 519000, China
| | - Lan Yao
- Department of Emergency Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong 519000, China
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Baglini E, Poggetti V, Cavallini C, Petroni D, Forini F, Nicolini G, Barresi E, Salerno S, Costa B, Iozzo P, Neglia D, Menichetti L, Taliani S, Da Settimo F. Targeting the Translocator Protein (18 kDa) in Cardiac Diseases: State of the Art and Future Opportunities. J Med Chem 2024; 67:17-37. [PMID: 38113353 PMCID: PMC10911791 DOI: 10.1021/acs.jmedchem.3c01716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 11/16/2023] [Accepted: 11/24/2023] [Indexed: 12/21/2023]
Abstract
Mitochondria dysfunctions are typical hallmarks of cardiac disorders (CDs). The multiple tasks of this energy-producing organelle are well documented, but its pathophysiologic involvement in several manifestations of heart diseases, such as altered electromechanical coupling, excitability, and arrhythmias, is still under investigation. The human 18 kDa translocator protein (TSPO) is a protein located on the outer mitochondrial membrane whose expression is altered in different pathological conditions, including CDs, making it an attractive therapeutic and diagnostic target. Currently, only a few TSPO ligands are employed in CDs and cardiac imaging. In this Perspective, we report an overview of the emerging role of TSPO at the heart level, focusing on the recent literature concerning the development of TSPO ligands used for fighting and imaging heart-related disease conditions. Accordingly, targeting TSPO might represent a successful strategy to achieve novel therapeutic and diagnostic strategies to unravel the fundamental mechanisms and to provide solutions to still unanswered questions in CDs.
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Affiliation(s)
- Emma Baglini
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Valeria Poggetti
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Chiara Cavallini
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Debora Petroni
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Francesca Forini
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Giuseppina Nicolini
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Elisabetta Barresi
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Silvia Salerno
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Barbara Costa
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Patricia Iozzo
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Danilo Neglia
- Fondazione
CNR/Regione Toscana Gabriele Monasterio, Cardiovascular and Imaging
Departments, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Luca Menichetti
- Institute
of Clinical Physiology, National Research Council of Italy, CNR Research Area, Via G. Moruzzi 1, Pisa 56124, Italy
| | - Sabrina Taliani
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
| | - Federico Da Settimo
- Department
of Pharmacy, University of Pisa, Via Bonanno 6, Pisa 56126, Italy
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Hsieh HH, Chu PA, Lin YH, Kao YCJ, Chung YH, Hsu ST, Mo JM, Wu CY, Peng SL. Imaging diabetic cardiomyopathy in a type 1 diabetic rat model using 18F-FEPPA PET. Nucl Med Biol 2024; 128-129:108878. [PMID: 38324923 DOI: 10.1016/j.nucmedbio.2024.108878] [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: 11/01/2023] [Revised: 01/08/2024] [Accepted: 01/22/2024] [Indexed: 02/09/2024]
Abstract
OBJECTIVE Diabetic patients often experience chronic inflammation and fibrosis in their cardiac tissues, highlighting the pressing need for the development of sensitive diagnostic methods for longitudinal assessment of diabetic cardiomyopathy. This study aims to evaluate the significance of an inflammatory marker known as translocator protein (TSPO) in a positron emission tomography (PET) protocol for longitudinally monitoring cardiac dysfunction in a diabetic animal model. Additionally, we compared the commonly used radiotracer, 18F-fluoro-2-deoxy-d-glucose (18F-FDG). METHODS Fourteen 7-week-old female Sprague-Dawley rats were used in this study. Longitudinal PET experiments were conducted using 18F-N-2-(2-fluoroethoxy)benzyl)-N-(4-phenoxypyridin-3-yl)acetamide (18F-FEPPA) (n = 3), the TSPO radiotracer, and 18F-FDG (n = 3), both before and after the onset of diabetes. Histological and immunohistochemical staining assays were also conducted in both the control (n = 4) and diabetes (n = 4) groups. RESULTS Results indicated a significant increase in cardiac tissue uptake of 18F-FEPPA after the onset of diabetes (P < 0.05), aligning with elevated TSPO levels observed in diabetic animals according to histological data. Conversely, the uptake of 18F-FDG in cardiac tissue significantly decreased after the onset of diabetes (P < 0.05). CONCLUSION These findings suggest that 18F-FEPPA can function as a sensitive probe for detecting chronic inflammation and fibrosis in the cardiac tissues of diabetic animals.
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Affiliation(s)
- Hsin-Hua Hsieh
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei Branch, Taipei, Taiwan
| | - Pei-An Chu
- Department of Biomedical Engineering, National Taiwan University, Taipei, Taiwan
| | - Yu-Hsin Lin
- Department of Pharmacy, National Yang Ming Chiao Tung University, Taipei Branch, Taipei, Taiwan; Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - Yu-Chieh Jill Kao
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei Branch, Taipei, Taiwan
| | - Yi-Hsiu Chung
- Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Shih-Ting Hsu
- Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Jia-Min Mo
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Chun-Yi Wu
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei Branch, Taipei, Taiwan.
| | - Shin-Lei Peng
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan; Neuroscience and Brain Disease Center, China Medical University, Taichung, Taiwan.
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Jahandideh A, Virta J, Li XG, Liljenbäck H, Moisio O, Ponkamo J, Rajala N, Alix M, Lehtonen J, Mäyränpää MI, Salminen TA, Knuuti J, Jalkanen S, Saraste A, Roivainen A. Vascular adhesion protein-1-targeted PET imaging in autoimmune myocarditis. J Nucl Cardiol 2023; 30:2760-2772. [PMID: 37758963 PMCID: PMC10682147 DOI: 10.1007/s12350-023-03371-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 08/06/2023] [Indexed: 09/29/2023]
Abstract
BACKGROUND Vascular adhesion protein-1 (VAP-1) is an adhesion molecule and primary amine oxidase, and Gallium-68-labeled 1,4,7,10-tetraazacyclododecane-N,N',N″,N‴-tetra-acetic acid conjugated sialic acid-binding immunoglobulin-like lectin 9 motif containing peptide ([68Ga]Ga-DOTA-Siglec-9) is a positron emission tomography (PET) tracer targeting VAP-1. We evaluated the feasibility of PET imaging with [68Ga]Ga-DOTA-Siglec-9 for the detection of myocardial lesions in rats with autoimmune myocarditis. METHODS Rats (n = 9) were immunized twice with porcine cardiac myosin in complete Freund's adjuvant. Control rats (n = 6) were injected with Freund's adjuvant alone. On day 21, in vivo PET/computed tomography (CT) imaging with [68Ga]Ga-DOTA-Siglec-9 was performed, followed by ex vivo autoradiography, histology, and immunohistochemistry of tissue sections. In addition, myocardial samples from three patients with cardiac sarcoidosis were studied. RESULTS [68Ga]Ga-DOTA-Siglec-9 PET/CT images of immunized rats showed higher uptake in myocardial lesions than in myocardium outside lesions (SUVmean, 0.5 ± 0.1 vs 0.3 ± 0.1; P = .003) or control rats (SUVmean, 0.2 ± 0.03; P < .0001), which was confirmed by ex vivo autoradiography of tissue sections. Immunohistochemistry showed VAP-1-positive staining in lesions of rats with myocarditis and in patients with cardiac sarcoidosis. CONCLUSION VAP-1-targeted [68Ga]Ga-DOTA-Siglec-9 PET is a potential novel technique for the detection of myocardial lesions.
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Affiliation(s)
- Arghavan Jahandideh
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland
| | - Jenni Virta
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland
| | - Xiang-Guo Li
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland
- InFLAMES Research Flagship Center, University of Turku, Turku, Finland
- Department of Chemistry, University of Turku, Turku, Finland
| | - Heidi Liljenbäck
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland
- Turku Center for Disease Modeling, University of Turku, Turku, Finland
| | - Olli Moisio
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland
| | - Jesse Ponkamo
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland
| | - Noora Rajala
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland
| | - Marion Alix
- Structural Bioinformatics Laboratory, Åbo Akademi University, Turku, Finland
| | - Jukka Lehtonen
- Heart and Lung Center, Helsinki University and Helsinki University Hospital, Helsinki, Finland
| | - Mikko I Mäyränpää
- Department of Pathology, Helsinki University and Helsinki University Hospital, Helsinki, Finland
| | - Tiina A Salminen
- InFLAMES Research Flagship Center, University of Turku, Turku, Finland
- Structural Bioinformatics Laboratory, Åbo Akademi University, Turku, Finland
| | - Juhani Knuuti
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland
- InFLAMES Research Flagship Center, University of Turku, Turku, Finland
| | - Sirpa Jalkanen
- InFLAMES Research Flagship Center, University of Turku, Turku, Finland
- MediCity Research Laboratory and Institute of Biomedicine, University of Turku, Turku, Finland
| | - Antti Saraste
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland
- Heart Center, Turku University Hospital and University of Turku, Turku, Finland
| | - Anne Roivainen
- Turku PET Centre, University of Turku, Åbo Akademi University and Turku University Hospital, 20520, Turku, Finland.
- InFLAMES Research Flagship Center, University of Turku, Turku, Finland.
- Turku Center for Disease Modeling, University of Turku, Turku, Finland.
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5
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Tang JM, McClennan A, Liu L, Hadway J, Ronald JA, Hicks JW, Hoffman L, Anazodo UC. A Protocol for Simultaneous In Vivo Imaging of Cardiac and Neuroinflammation in Dystrophin-Deficient MDX Mice Using [ 18F]FEPPA PET. Int J Mol Sci 2023; 24:ijms24087522. [PMID: 37108685 PMCID: PMC10144317 DOI: 10.3390/ijms24087522] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 04/14/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a neuromuscular disorder caused by dystrophin loss-notably within muscles and the central neurons system. DMD presents as cognitive weakness, progressive skeletal and cardiac muscle degeneration until pre-mature death from cardiac or respiratory failure. Innovative therapies have improved life expectancy; however, this is accompanied by increased late-onset heart failure and emergent cognitive degeneration. Thus, better assessment of dystrophic heart and brain pathophysiology is needed. Chronic inflammation is strongly associated with skeletal and cardiac muscle degeneration; however, neuroinflammation's role is largely unknown in DMD despite being prevalent in other neurodegenerative diseases. Here, we present an inflammatory marker translocator protein (TSPO) positron emission tomography (PET) protocol for in vivo concomitant assessment of immune cell response in hearts and brains of a dystrophin-deficient mouse model [mdx:utrn(+/-)]. Preliminary analysis of whole-body PET imaging using the TSPO radiotracer, [18F]FEPPA in four mdx:utrn(+/-) and six wildtype mice are presented with ex vivo TSPO-immunofluorescence tissue staining. The mdx:utrn(+/-) mice showed significant elevations in heart and brain [18F]FEPPA activity, which correlated with increased ex vivo fluorescence intensity, highlighting the potential of TSPO-PET to simultaneously assess presence of cardiac and neuroinflammation in dystrophic heart and brain, as well as in several organs within a DMD model.
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Affiliation(s)
- Joanne M Tang
- Department of Medical Biophysics, Western University, London, ON N6A 3K7, Canada
- Lawson Health Research Institute, London, ON N6A 4V2, Canada
| | - Andrew McClennan
- Department of Medical Biophysics, Western University, London, ON N6A 3K7, Canada
- Lawson Health Research Institute, London, ON N6A 4V2, Canada
| | - Linshan Liu
- Lawson Health Research Institute, London, ON N6A 4V2, Canada
| | - Jennifer Hadway
- Lawson Health Research Institute, London, ON N6A 4V2, Canada
| | - John A Ronald
- Department of Medical Biophysics, Western University, London, ON N6A 3K7, Canada
- Robarts Research Institute, Western University, London, ON N6A 3K7, Canada
| | - Justin W Hicks
- Department of Medical Biophysics, Western University, London, ON N6A 3K7, Canada
- Lawson Health Research Institute, London, ON N6A 4V2, Canada
| | - Lisa Hoffman
- Department of Medical Biophysics, Western University, London, ON N6A 3K7, Canada
- Lawson Health Research Institute, London, ON N6A 4V2, Canada
- Department of Anatomy and Cell Biology, Western University, London, ON N6A 3K7, Canada
| | - Udunna C Anazodo
- Department of Medical Biophysics, Western University, London, ON N6A 3K7, Canada
- Lawson Health Research Institute, London, ON N6A 4V2, Canada
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC H3A 0G4, Canada
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Recent Advances in Cardiovascular Diseases Research Using Animal Models and PET Radioisotope Tracers. Int J Mol Sci 2022; 24:ijms24010353. [PMID: 36613797 PMCID: PMC9820417 DOI: 10.3390/ijms24010353] [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: 11/10/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
Cardiovascular diseases (CVD) is a collective term describing a range of conditions that affect the heart and blood vessels. Due to the varied nature of the disorders, distinguishing between their causes and monitoring their progress is crucial for finding an effective treatment. Molecular imaging enables non-invasive visualisation and quantification of biological pathways, even at the molecular and subcellular levels, what is essential for understanding the causes and development of CVD. Positron emission tomography imaging is so far recognized as the best method for in vivo studies of the CVD related phenomena. The imaging is based on the use of radioisotope-labelled markers, which have been successfully used in both pre-clinical research and clinical studies. Current research on CVD with the use of such radioconjugates constantly increases our knowledge and understanding of the causes, and brings us closer to effective monitoring and treatment. This review outlines recent advances in the use of the so-far available radioisotope markers in the research on cardiovascular diseases in rodent models, points out the problems and provides a perspective for future applications of PET imaging in CVD studies.
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18F-Radiolabeled Translocator Protein (TSPO) PET Tracers: Recent Development of TSPO Radioligands and Their Application to PET Study. Pharmaceutics 2022; 14:pharmaceutics14112545. [PMID: 36432736 PMCID: PMC9697781 DOI: 10.3390/pharmaceutics14112545] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022] Open
Abstract
Translocator protein 18 kDa (TSPO) is a transmembrane protein in the mitochondrial membrane, which has been identified as a peripheral benzodiazepine receptor. TSPO is generally present at high concentrations in steroid-producing cells and plays an important role in steroid synthesis, apoptosis, and cell proliferation. In the central nervous system, TSPO expression is relatively modest under normal physiological circumstances. However, some pathological disorders can lead to changes in TSPO expression. Overexpression of TSPO is associated with several diseases, such as neurodegenerative diseases, neuroinflammation, brain injury, and cancers. TSPO has therefore become an effective biomarker of related diseases. Positron emission tomography (PET), a non-invasive molecular imaging technique used for the clinical diagnosis of numerous diseases, can detect diseases related to TSPO expression. Several radiolabeled TSPO ligands have been developed for PET. In this review, we describe recent advances in the development of TSPO ligands, and 18F-radiolabeled TSPO in particular, as PET tracers. This review covers pharmacokinetic studies, preclinical and clinical trials of 18F-labeled TSPO PET ligands, and the synthesis of TSPO ligands.
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8
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Adhikari A, Zhang MR, Tiwari AK. Acetamidobenzoxazolone scaffold as a promising translocator protein (18 kDa, TSPO) marker for neuroinflammation imaging: Advancement in last decennial period. Drug Dev Res 2022; 83:1519-1533. [PMID: 36074736 DOI: 10.1002/ddr.21989] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 07/10/2022] [Accepted: 07/14/2022] [Indexed: 11/09/2022]
Abstract
Inflammation has been linked to the onset and progression of a wide range of neuropathological disorders. The well-conserved outer mitochondrial membrane 18 kDa translocator protein (TSPO) is perceived as an in vivo neuroinflammation marker. A dearth of a reference region, genetic disparity influencing the ligand's affinity for TSPO, and a substantial signal in the endothelium of the brain veins contributes toward complications in quantifying TSPO positron emission tomography (PET) image. Up to the present time several radiotracers based on different pharmacophore such as (R)[11 C]PK11195, [18 F]DPA714, [11 C]PBR28, [11 C]ER176, and many more have been recognized for envisaging the prominent TSPO level observed in neurological conditions. Recently acetamidobenzoxazolone (ABO) scaffold, a bicyclic ring system composed of a phenyl ring fused to a carbamate and its substituted radiolabelled analogues especially at C-5 position has evidenced encouraging outcomes as next generation of TSPO PET ligands. Diverse ABO framework-based TSPO ligands have been designed embracing imperative aspects such as lipophilicity, metabolic profile, and capability to penetrate the blood-brain barrier apart from least effect of polymorphism (rs6971). Over the years numerous systematic literature reviews compiling different structural class of TSPO ligands characterized on the grounds of their binding affinity and metabolite profile have been reported but none is especially focused toward a fascinating benzoxazolone scaffold. This review exclusively bestows an overview of the recent advancements on ABO derivatives with neuroinflammation imaging potential and emphases on the structural features accountable for visualizing TSPO in-vivo with collation of published reports during last 10 years.
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Affiliation(s)
- Anupriya Adhikari
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
| | - Ming-Rong Zhang
- Department of Advanced Nuclear Medicine Sciences, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Anjani Kumar Tiwari
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, Uttar Pradesh, India
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9
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Viviano M, Barresi E, Siméon FG, Costa B, Taliani S, Da Settimo F, Pike VW, Castellano S. Essential Principles and Recent Progress in the Development of TSPO PET Ligands for Neuroinflammation Imaging. Curr Med Chem 2022; 29:4862-4890. [PMID: 35352645 PMCID: PMC10080361 DOI: 10.2174/0929867329666220329204054] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 12/21/2021] [Accepted: 01/25/2022] [Indexed: 11/22/2022]
Abstract
The translocator protein 18kDa (TSPO) is expressed in the outer mitochondrial membrane and is implicated in several functions, including cholesterol transport and steroidogenesis. Under normal physiological conditions, TSPO is present in very low concentrations in the human brain but is markedly upregulated in response to brain injury and inflammation. This upregulation is strongly associated with activated microglia. Therefore, TSPO is particularly suited for assessing active gliosis associated with brain lesions following injury or disease. For over three decades, TSPO has been studied as a biomarker. Numerous radioligands for positron emission tomography (PET) that target TSPO have been developed for imaging inflammatory progression in the brain. Although [11C]PK11195, the prototypical first-generation PET radioligand, is still widely used for in vivo studies, mainly now as its single more potent R-enantiomer, it has severe limitations, including low sensitivity and poor amenability to quantification. Second-generation radioligands are characterized by higher TSPO specific signals but suffer from other drawbacks, such as sensitivity to the TSPO single nucleotide polymorphism (SNP) rs6971. Therefore, their applications in human studies have the burden of needing to genotype subjects. Consequently, recent efforts are focused on developing improved radioligands that combine the optimal features of the second generation with the ability to overcome the differences in binding affinities across the population. This review presents essential principles in the design and development of TSPO PET ligands and discusses prominent examples among the main chemotypes.
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Affiliation(s)
- Monica Viviano
- Department of Pharmacy, University of Salerno, 84084 Fisciano (SA), Italy
| | | | - Fabrice G. Siméon
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Barbara Costa
- Department of Pharmacy, University of Pisa, 56126, Pisa, Italy
| | - Sabrina Taliani
- Department of Pharmacy, University of Pisa, 56126, Pisa, Italy
| | | | - Victor W. Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sabrina Castellano
- Department of Pharmacy, University of Salerno, 84084 Fisciano (SA), Italy
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van der Geest KSM, Sandovici M, Nienhuis PH, Slart RHJA, Heeringa P, Brouwer E, Jiemy WF. Novel PET Imaging of Inflammatory Targets and Cells for the Diagnosis and Monitoring of Giant Cell Arteritis and Polymyalgia Rheumatica. Front Med (Lausanne) 2022; 9:902155. [PMID: 35733858 PMCID: PMC9207253 DOI: 10.3389/fmed.2022.902155] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 05/13/2022] [Indexed: 12/26/2022] Open
Abstract
Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are two interrelated inflammatory diseases affecting patients above 50 years of age. Patients with GCA suffer from granulomatous inflammation of medium- to large-sized arteries. This inflammation can lead to severe ischemic complications (e.g., irreversible vision loss and stroke) and aneurysm-related complications (such as aortic dissection). On the other hand, patients suffering from PMR present with proximal stiffness and pain due to inflammation of the shoulder and pelvic girdles. PMR is observed in 40-60% of patients with GCA, while up to 21% of patients suffering from PMR are also affected by GCA. Due to the risk of ischemic complications, GCA has to be promptly treated upon clinical suspicion. The treatment of both GCA and PMR still heavily relies on glucocorticoids (GCs), although novel targeted therapies are emerging. Imaging has a central position in the diagnosis of GCA and PMR. While [18F]fluorodeoxyglucose (FDG)-positron emission tomography (PET) has proven to be a valuable tool for diagnosis of GCA and PMR, it possesses major drawbacks such as unspecific uptake in cells with high glucose metabolism, high background activity in several non-target organs and a decrease of diagnostic accuracy already after a short course of GC treatment. In recent years, our understanding of the immunopathogenesis of GCA and, to some extent, PMR has advanced. In this review, we summarize the current knowledge on the cellular heterogeneity in the immunopathology of GCA/PMR and discuss how recent advances in specific tissue infiltrating leukocyte and stromal cell profiles may be exploited as a source of novel targets for imaging. Finally, we discuss prospective novel PET radiotracers that may be useful for the diagnosis and treatment monitoring in GCA and PMR.
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Affiliation(s)
- Kornelis S. M. van der Geest
- Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Maria Sandovici
- Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Pieter H. Nienhuis
- Department of Nuclear Medicine and Molecular Imaging, Medical Imaging Center, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Riemer H. J. A. Slart
- Department of Nuclear Medicine and Molecular Imaging, Medical Imaging Center, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Department of Biomedical Photonic Imaging Group, University of Twente, Enschede, Netherlands
| | - Peter Heeringa
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Elisabeth Brouwer
- Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - William F. Jiemy
- Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
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11
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Abstract
PURPOSE OF REVIEW Successful treatment of cancer can be hampered by the attendant risk of cardiotoxicity, manifesting as cardiomyopathy, left ventricle systolic dysfunction and, in some cases, heart failure. This risk can be mitigated if the injury to the heart is detected before the onset to irreversible cardiac impairment. The gold standard for cardiac imaging in cardio-oncology is echocardiography. Despite improvements in the application of this modality, it is not typically sensitive to sub-clinical or early-stage dysfunction. We identify in this review some emerging tracers for detecting incipient cardiotoxicity by positron emission tomography (PET). RECENT FINDINGS Vectors labeled with positron-emitting radionuclides (e.g., carbon-11, fluorine-18, gallium-68) are now available to study cardiac function, metabolism, and tissue repair in preclinical models. Many of these probes are highly sensitive to early damage, thereby potentially addressing the limitations of current imaging approaches, and show promise in preliminary clinical evaluations. The overlapping pathophysiology between cardiotoxicity and heart failure significantly expands the number of imaging tools available to cardio-oncology. This is highlighted by the emergence of radiolabeled probes targeting fibroblast activation protein (FAP) for sensitive detection of dysregulated healing process that underpins adverse cardiac remodeling. The growth of PET scanner technology also creates an opportunity for a renaissance in metabolic imaging in cardio-oncology research.
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Affiliation(s)
- James M. Kelly
- Division of Radiopharmaceutical Sciences and Molecular Imaging Innovations Institute (MI3), Weill Cornell Medicine, Belfer Research Building, Room BB-1604, 413 East 69th St, New York, NY 10021 USA
- Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY 10021 USA
| | - John W. Babich
- Division of Radiopharmaceutical Sciences and Molecular Imaging Innovations Institute (MI3), Weill Cornell Medicine, Belfer Research Building, Room BB-1604, 413 East 69th St, New York, NY 10021 USA
- Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY 10021 USA
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10021 USA
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12
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Jahandideh A, Ståhle M, Virta J, Li XG, Liljenbäck H, Moisio O, Knuuti J, Roivainen A, Saraste A. Evaluation of [ 68Ga]Ga-NODAGA-RGD for PET Imaging of Rat Autoimmune Myocarditis. Front Med (Lausanne) 2022; 8:783596. [PMID: 34977085 PMCID: PMC8714834 DOI: 10.3389/fmed.2021.783596] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 11/15/2021] [Indexed: 12/26/2022] Open
Abstract
The 68Gallium-labeled 1,4,7-triazacyclononane-1-glutaric acid-4,7-diacetic acid conjugated radiolabelled arginine-glycine-aspartic acid peptide ([68Ga]Ga-NODAGA-RGD) is a positron emission tomography (PET) tracer binding to cell surface receptor αvβ3 integrin that is upregulated during angiogenesis and inflammation. We studied whether αvβ3 targeting PET imaging can detect myocardial inflammation in a rat model of autoimmune myocarditis. To induce myocarditis, rats (n = 8) were immunized with porcine cardiac myosin in complete Freund's adjuvant on days 0 and 7. Control rats (n = 8) received Freund's adjuvant alone. On day 21, in vivo PET/CT imaging with [68Ga]Ga-NODAGA-RGD followed by ex vivo autoradiography and immunohistochemistry were carried out. Inflammatory lesions were detected histologically in the myocardium of 7 out of 8 immunized rats. In vivo PET images showed higher [68Ga]Ga-NODAGA-RGD accumulation in the myocardium of rats with inflammation than the non-inflamed myocardium of control rats (SUVmean 0.4 ± 0.1 vs. 0.1 ± 0.02; P = 0.00006). Ex vivo autoradiography and histology confirmed that [68Ga]Ga-NODAGA-RGD uptake co-localized with inflammatory lesions containing αvβ3 integrin-positive capillary-like structures. A non-specific [68Ga]Ga-DOTA-(RGE)2 tracer showed 76% lower uptake than [68Ga]Ga-NODAGA-RGD in the inflamed myocardium. Our results indicate that αvβ3 integrin-targeting [68Ga]Ga-NODAGA-RGD is a potential PET tracer for the specific detection of active inflammatory lesions in autoimmune myocarditis.
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Affiliation(s)
| | - Mia Ståhle
- Turku PET Centre, University of Turku, Turku, Finland
| | - Jenni Virta
- Turku PET Centre, University of Turku, Turku, Finland
| | - Xiang-Guo Li
- Turku PET Centre, University of Turku, Turku, Finland
| | - Heidi Liljenbäck
- Turku PET Centre, University of Turku, Turku, Finland.,Turku Center for Disease Modeling, University of Turku, Turku, Finland
| | - Olli Moisio
- Turku PET Centre, University of Turku, Turku, Finland
| | - Juhani Knuuti
- Turku PET Centre, University of Turku, Turku, Finland.,Turku PET Centre, Turku University Hospital, Turku, Finland
| | - Anne Roivainen
- Turku PET Centre, University of Turku, Turku, Finland.,Turku Center for Disease Modeling, University of Turku, Turku, Finland.,Turku PET Centre, Turku University Hospital, Turku, Finland
| | - Antti Saraste
- Turku PET Centre, University of Turku, Turku, Finland.,Turku PET Centre, Turku University Hospital, Turku, Finland.,Heart Center, Turku University Hospital and University of Turku, Turku, Finland
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13
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Lee SH, Denora N, Laquintana V, Mangiatordi GF, Lopedota A, Lopalco A, Cutrignelli A, Franco M, Delre P, Song IH, Kim HW, Kim SB, Park HS, Kim K, Lee SY, Youn H, Lee BC, Kim SE. Radiosynthesis and characterization of [ 18F]BS224: a next-generation TSPO PET ligand insensitive to the rs6971 polymorphism. Eur J Nucl Med Mol Imaging 2021; 49:110-124. [PMID: 34783879 PMCID: PMC8712300 DOI: 10.1007/s00259-021-05617-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 11/03/2021] [Indexed: 01/03/2023]
Abstract
PURPOSE Translocator protein 18-kDa (TSPO) positron emission tomography (PET) is a valuable tool to detect neuroinflammed areas in a broad spectrum of neurodegenerative diseases. However, the clinical application of second-generation TSPO ligands as biomarkers is limited because of the presence of human rs6971 polymorphism that affects their binding. Here, we describe the ability of a new TSPO ligand, [18F]BS224, to identify abnormal TSPO expression in neuroinflammation independent of the rs6971 polymorphism. METHODS An in vitro competitive inhibition assay of BS224 was conducted with [3H]PK 11195 using membrane proteins isolated from 293FT cells expressing TSPO-wild type (WT) or TSPO-mutant A147T (Mut), corresponding to a high-affinity binder (HAB) and low-affinity binder (LAB), respectively. Molecular docking was performed to investigate the interaction of BS224 with the binding sites of rat TSPO-WT and TSPO-Mut. We synthesized a new 18F-labeled imidazopyridine acetamide ([18F]BS224) using boronic acid pinacol ester 6 or iodotoluene tosylate precursor 7, respectively, via aromatic 18F-fluorination. Dynamic PET scanning was performed up to 90 min after the injection of [18F]BS224 to healthy mice, and PET imaging data were obtained to estimate its absorbed doses in organs. To evaluate in vivo TSPO-specific uptake of [18F]BS224, lipopolysaccharide (LPS)-induced inflammatory and ischemic stroke rat models were used. RESULTS BS224 exhibited a high affinity (Ki = 0.51 nM) and selectivity for TSPO. The ratio of IC50 values of BS224 for LAB to that for HAB indicated that the TSPO binding affinity of BS224 has low binding sensitivity to the rs6971 polymorphism and it was comparable to that of PK 11195, which is not sensitive to the polymorphism. Docking simulations showed that the binding mode of BS224 is not affected by the A147T mutation and consequently supported the observed in vitro selectivity of [18F]BS224 regardless of polymorphisms. With optimal radiochemical yield (39 ± 6.8%, decay-corrected) and purity (> 99%), [18F]BS224 provided a clear visible image of the inflammatory lesion with a high signal-to-background ratio in both animal models (BPND = 1.43 ± 0.17 and 1.57 ± 0.37 in the LPS-induced inflammatory and ischemic stroke rat models, respectively) without skull uptake. CONCLUSION Our results suggest that [18F]BS224 may be a promising TSPO ligand to gauge neuroinflammatory disease-related areas in a broad range of patients irrespective of the common rs6971 polymorphism.
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Affiliation(s)
- Sang Hee Lee
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, 13620 Republic of Korea
- Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Nunzio Denora
- Department of Pharmacy – Drug Sciences, University of Bari “A. Moro”, 70121 Bari, Italy
| | - Valentino Laquintana
- Department of Pharmacy – Drug Sciences, University of Bari “A. Moro”, 70121 Bari, Italy
| | | | - Angela Lopedota
- Department of Pharmacy – Drug Sciences, University of Bari “A. Moro”, 70121 Bari, Italy
| | - Antonio Lopalco
- Department of Pharmacy – Drug Sciences, University of Bari “A. Moro”, 70121 Bari, Italy
| | - Annalisa Cutrignelli
- Department of Pharmacy – Drug Sciences, University of Bari “A. Moro”, 70121 Bari, Italy
| | - Massimo Franco
- Department of Pharmacy – Drug Sciences, University of Bari “A. Moro”, 70121 Bari, Italy
| | - Pietro Delre
- Institute of Crystallography, National Research Council, Via G. Amendola 122/O, 70126 Bari, Italy
- Department of Chemistry, University of Bari “A. Moro”, Via E. Orabona, 4, 70125 Bari, Italy
| | - In Ho Song
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, 13620 Republic of Korea
| | - Hye Won Kim
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, 13620 Republic of Korea
- Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Su Bin Kim
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, 13620 Republic of Korea
- Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Hyun Soo Park
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, 13620 Republic of Korea
| | - Kyungmin Kim
- Department of Nuclear Medicine, Seoul National University Hospital, Seoul, 03080 Republic of Korea
- Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, 03080 Republic of Korea
- Laboratory of Molecular Imaging and Therapy, Cancer Research Institute, Seoul National University College of Medicine, Seoul, 03080 Republic of Korea
| | - Seok-Yong Lee
- Department of Nuclear Medicine, Seoul National University Hospital, Seoul, 03080 Republic of Korea
- Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, 03080 Republic of Korea
- Laboratory of Molecular Imaging and Therapy, Cancer Research Institute, Seoul National University College of Medicine, Seoul, 03080 Republic of Korea
| | - Hyewon Youn
- Department of Nuclear Medicine, Seoul National University Hospital, Seoul, 03080 Republic of Korea
- Laboratory of Molecular Imaging and Therapy, Cancer Research Institute, Seoul National University College of Medicine, Seoul, 03080 Republic of Korea
| | - Byung Chul Lee
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, 13620 Republic of Korea
- Center for Nanomolecular Imaging and Innovative Drug Development, Advanced Institutes of Convergence Technology, Suwon, 16229 Republic of Korea
| | - Sang Eun Kim
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, 13620 Republic of Korea
- Center for Nanomolecular Imaging and Innovative Drug Development, Advanced Institutes of Convergence Technology, Suwon, 16229 Republic of Korea
- Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, 08826 Republic of Korea
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14
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Direct Comparison of [ 18F]F-DPA with [ 18F]DPA-714 and [ 11C]PBR28 for Neuroinflammation Imaging in the same Alzheimer's Disease Model Mice and Healthy Controls. Mol Imaging Biol 2021; 24:157-166. [PMID: 34542805 PMCID: PMC8760190 DOI: 10.1007/s11307-021-01646-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 07/22/2021] [Accepted: 08/23/2021] [Indexed: 11/02/2022]
Abstract
PURPOSE In this study we compared the recently developed TSPO tracer [18F]F-DPA, with [18F]DPA-714 and [11C]PBR28 by performing in vivo PET imaging on the same Alzheimer's disease mouse model APP/PS1-21 (TG) and wild-type (WT) mice with all three radiotracers. PROCEDURES To compare the radiotracer uptake, percentage of injected dose/mL (%ID/mL), standardized uptake value ratios to cerebellum (SUVRCB), and voxel-wise analyses were performed. RESULTS The peak uptake of [18F]F-DPA was higher than 4.3% ID/mL, while [18F]DPA-714 reached just over 3% ID/mL, and [11C]PBR28 was over 4% ID/mL in only one brain region in the WT mice. The peak/60-min uptake ratios of [18F]F-DPA were significantly higher (p < 0.001) than those of [18F]DPA-714 and [11C]PBR28. The differences in [18F]F-DPA SUVRCB between WT and TG mice were highly significant (p < 0.001) in the three studied time periods after injection. [18F]DPA-714 uptake was significantly higher in TG mice starting in the 20-40-min timeframe and increased thereafter, whereas [11C]PBR28 uptake became significant at 10-20 min (p < 0.05). The voxel-wise analysis confirmed the differences between the radiotracers. CONCLUSIONS [18F]F-DPA displays higher brain uptake, higher TG-to-WT SUVRCB ratios, and faster clearance than [18F]DPA-714 and [11C]PBR28, and could prove useful for detecting low levels of inflammation and allow for shorter dynamic PET scans.
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15
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Feasibility of TSPO-Specific Positron Emission Tomography Radiotracer for Evaluating Paracetamol-Induced Liver Injury. Diagnostics (Basel) 2021; 11:diagnostics11091661. [PMID: 34574002 PMCID: PMC8467059 DOI: 10.3390/diagnostics11091661] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/06/2021] [Accepted: 09/09/2021] [Indexed: 01/16/2023] Open
Abstract
Macrophages are activated during the early phase of paracetamol-induced liver injury (PLI). [18F]GE180 is a radiolabeled ligand that recognizes the macrophage translocator protein (TSPO). In this study, we evaluated the feasibility of a TSPO-specific radiotracer in a rat model of PLI. A rat model of liver injury was induced by intraperitoneal administration of paracetamol. [18F]GE180 positron emission tomography (PET) images were obtained after 24 h. The maximal and mean standardized uptake values (SUVmax and SUVav) of the liver and serum biomarker levels were examined. The TSPO expression level was examined using real-time polymerase chain reaction and Western blot analysis. [18F]GE180 hepatic uptake in the PLI group was significantly higher than that in the control group (SUVmax p = 0.001; SUVav p = 0.005). Both mRNA and protein TSPO expression levels were higher in the PLI group. The mRNA expression level of TSPO was significantly correlated with [18F]GE180 hepatic uptake in both groups (SUVmax p = 0.019; SUVav p = 0.007). [18F]GE180 hepatic uptake in the PLI group showed a significant positive correlation with ALT24 and ALT48 (ALT24 p = 0.016; ALT48p = 0.002). [18F]GE180 enabled visualization of PLI through TSPO overexpression. Our results support the potential utility of hepatic uptake by TSPO-PET as a non-invasive imaging biomarker for the early phase of PLI.
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16
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Balogh V, MacAskill MG, Hadoke PWF, Gray GA, Tavares AAS. Positron Emission Tomography Techniques to Measure Active Inflammation, Fibrosis and Angiogenesis: Potential for Non-invasive Imaging of Hypertensive Heart Failure. Front Cardiovasc Med 2021; 8:719031. [PMID: 34485416 PMCID: PMC8416043 DOI: 10.3389/fcvm.2021.719031] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 07/22/2021] [Indexed: 12/11/2022] Open
Abstract
Heart failure, which is responsible for a high number of deaths worldwide, can develop due to chronic hypertension. Heart failure can involve and progress through several different pathways, including: fibrosis, inflammation, and angiogenesis. Early and specific detection of changes in the myocardium during the transition to heart failure can be made via the use of molecular imaging techniques, including positron emission tomography (PET). Traditional cardiovascular PET techniques, such as myocardial perfusion imaging and sympathetic innervation imaging, have been established at the clinical level but are often lacking in pathway and target specificity that is important for assessment of heart failure. Therefore, there is a need to identify new PET imaging markers of inflammation, fibrosis and angiogenesis that could aid diagnosis, staging and treatment of hypertensive heart failure. This review will provide an overview of key mechanisms underlying hypertensive heart failure and will present the latest developments in PET probes for detection of cardiovascular inflammation, fibrosis and angiogenesis. Currently, selective PET probes for detection of angiogenesis remain elusive but promising PET probes for specific targeting of inflammation and fibrosis are rapidly progressing into clinical use.
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Affiliation(s)
- Viktoria Balogh
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom.,Edinburgh Imaging, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom
| | - Mark G MacAskill
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom.,Edinburgh Imaging, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom
| | - Patrick W F Hadoke
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom
| | - Gillian A Gray
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom
| | - Adriana A S Tavares
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom.,Edinburgh Imaging, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom
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17
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Ailuno G, Iacobazzi RM, Lopalco A, Baldassari S, Arduino I, Azzariti A, Pastorino S, Caviglioli G, Denora N. The Pharmaceutical Technology Approach on Imaging Innovations from Italian Research. Pharmaceutics 2021; 13:1214. [PMID: 34452175 PMCID: PMC8402236 DOI: 10.3390/pharmaceutics13081214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/27/2021] [Accepted: 08/02/2021] [Indexed: 11/16/2022] Open
Abstract
Many modern therapeutic approaches are based on precise diagnostic evidence, where imaging procedures play an essential role. To date, in the diagnostic field, a plethora of agents have been investigated to increase the selectivity and sensitivity of diagnosis. However, the most common drawbacks of conventional imaging agents reside in their non-specificity, short imaging time, instability, and toxicity. Moreover, routinely used diagnostic agents have low molecular weights and consequently a rapid clearance and renal excretion, and this represents a limitation if long-lasting imaging analyses are to be conducted. Thus, the development of new agents for in vivo diagnostics requires not only a deep knowledge of the physical principles of the imaging techniques and of the physiopathological aspects of the disease but also of the relative pharmaceutical and biopharmaceutical requirements. In this scenario, skills in pharmaceutical technology have become highly indispensable in order to respond to these needs. This review specifically aims to collect examples of newly developed diagnostic agents connoting the importance of an appropriate formulation study for the realization of effective products. Within the context of pharmaceutical technology research in Italy, several groups have developed and patented promising agents for fluorescence and radioactive imaging, the most relevant of which are described hereafter.
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Affiliation(s)
- Giorgia Ailuno
- Department of Pharmacy, University of Genova, Viale Cembrano 4, 16148 Genova, Italy; (G.A.); (S.B.)
| | - Rosa Maria Iacobazzi
- Laboratory of Experimental Pharmacology, IRCCS Istituto Tumori “Giovanni Paolo II”, O. Flacco St., 70124 Bari, Italy; (R.M.I.); (A.A.)
| | - Antonio Lopalco
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari “Aldo Moro”, Orabona St. 4, 70125 Bari, Italy; (A.L.); (I.A.)
| | - Sara Baldassari
- Department of Pharmacy, University of Genova, Viale Cembrano 4, 16148 Genova, Italy; (G.A.); (S.B.)
| | - Ilaria Arduino
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari “Aldo Moro”, Orabona St. 4, 70125 Bari, Italy; (A.L.); (I.A.)
| | - Amalia Azzariti
- Laboratory of Experimental Pharmacology, IRCCS Istituto Tumori “Giovanni Paolo II”, O. Flacco St., 70124 Bari, Italy; (R.M.I.); (A.A.)
| | - Sara Pastorino
- Nuclear Medicine Unit, S. Andrea Hospital, via Vittorio Veneto 197, 19124 La Spezia, Italy;
| | - Gabriele Caviglioli
- Department of Pharmacy, University of Genova, Viale Cembrano 4, 16148 Genova, Italy; (G.A.); (S.B.)
| | - Nunzio Denora
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari “Aldo Moro”, Orabona St. 4, 70125 Bari, Italy; (A.L.); (I.A.)
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18
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Adhikari A, Singh P, Mahar KS, Adhikari M, Adhikari B, Zhang MR, Tiwari AK. Mapping of Translocator Protein (18 kDa) in Peripheral Sterile Inflammatory Disease and Cancer through PET Imaging. Mol Pharm 2021; 18:1507-1529. [PMID: 33645995 DOI: 10.1021/acs.molpharmaceut.1c00002] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Positron emission tomography (PET) imaging of the translocator 18 kDa protein (TSPO) with radioligands has become an effective means of research in peripheral inflammatory conditions that occur in many diseases and cancers. The peripheral sterile inflammatory diseases (PSIDs) are associated with a diverse group of disorders that comprises numerous enduring insults including the cardiovascular, respiratory, gastrointestinal, or musculoskeletal system. TSPO has recently been introduced as a potential biomarker for peripheral sterile inflammatory diseases (PSIDs). The major critical issue related to PSIDs is its timely characterization and localization of inflammatory foci for proper therapy of patients. As an alternative to metabolic imaging, protein imaging expressed on immune cells after activation is of great importance. The five transmembrane domain translocator protein-18 kDa (TSPO) is upregulated on the mitochondrial cell surface of macrophages during inflammation, serving as a potential ligand for PET tracers. Additionally, the overexpressed TSPO protein has been positively correlated with various tumor malignancies. In view of the association of escalated TSPO expression in both disease conditions, it is an immensely important biomarker for PET imaging in oncology and PSIDs. In this review, we summarize the most outstanding advances on TSPO-targeted PSIDs and cancer in the development of TSPO ligands as a potential diagnostic tool, specifically discussing the last five years.
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Affiliation(s)
- Anupriya Adhikari
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, (A Central University), Lucknow, Uttar Pradesh 226025, India
| | - Priya Singh
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, A Central University, Lucknow, Uttar Pradesh 226025, India
| | - Kamalesh S Mahar
- Birbal Sahni Institute of Palaeosciences, Lucknow, Uttar Pradesh 226007, India
| | - Manish Adhikari
- The George Washington University, Washington, D.C. 20052, United States
| | - Bhawana Adhikari
- Plasma Bio-science Research Center, Kwangwoon University, Seoul 01897, South Korea
| | - Ming-Rong Zhang
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba 263-8555, Japan
| | - Anjani Kumar Tiwari
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, (A Central University), Lucknow, Uttar Pradesh 226025, India
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19
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Non- 18F-FDG/ 18F-NaF Radiotracers Proposed for the Diagnosis and Management of Diseases of the Heart and Vasculature. PET Clin 2021; 16:273-284. [PMID: 33589388 DOI: 10.1016/j.cpet.2020.12.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
18F-fluorodeoxyglucose (18F-FDG) and 18F-sodium fluoride (18F-NaF) are front-runners in PET. However, these tracers have limitations in the imaging of diseases in the heart. A multitude of other radiotracers have been identified as potentially useful PET agents in the identification of cardiovascular disease. This critical review examines recent studies with the use of non-18F-FDG/18F-NaF radiotracers in the identification and surveillance of cardiovascular diseases. We highlight the need for further investigation into alternative PET radiotracers to demonstrate their clinical value in the management of these pathologies.
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Mou T, Tian J, Tian Y, Yun M, Li J, Dong W, Lu X, Zhu Z, Mi H, Zhang X, Li X. Automated synthesis and preliminary evaluation of [ 18F]FDPA for cardiac inflammation imaging in rats after myocardial infarction. Sci Rep 2020; 10:18685. [PMID: 33122775 PMCID: PMC7596090 DOI: 10.1038/s41598-020-75705-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 10/19/2020] [Indexed: 11/26/2022] Open
Abstract
A translocator protein 18 kDa targeted radiotracer, N,N-diethyl-2-(2-(4-[18F]fluorophenyl)-5,7-dimethylpyrazolo[1,5-a] pyrimidin-3-yl) acetamide ([18F]FDPA), was automated synthetized and evaluated for cardiac inflammation imaging. Various reaction conditions for an automated synthesis were systematically optimized. MicroPET/CT imaging were performed on normal rats and rats with myocardial infarction (MI). Normalized SUV ratios of [18F]FDPA to [13N]NH3 (NSRs) in different regions were calculated to normalize the uptake of [18F]FDPA to perfusion. The amount of TBAOMs and the volume/proportion of water were crucial for synthesis. After optimization, the total synthesis time was 68 min. The non-decay corrected radiochemical yields (RCYs) and molar activities were 19.9 ± 1.7% and 169.7 ± 46.5 GBq/μmol, respectively. In normal rats, [18F]FDPA showed a high and stable cardiac uptake and fast clearance from other organs. In MI rats, NSRs in the peri-infarct and infarct regions, which were infiltrated with massive inflammatory cells revealed by pathology, were higher than that in the remote region (1.20 ± 0.01 and 1.08 ± 0.10 vs. 0.89 ± 0.05, respectively). [18F]FDPA was automated synthesized with high RCYs and molar activities. It showed a high uptake in inflammation regions and offered a wide time window for cardiac imaging, indicating it could be a potential cardiac inflammation imaging agent.
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Affiliation(s)
- Tiantian Mou
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Jing Tian
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Yi Tian
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Mingkai Yun
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Junqi Li
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Wei Dong
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Xia Lu
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Ziwei Zhu
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Hongzhi Mi
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China
| | - Xiaoli Zhang
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China.
| | - Xiang Li
- Department of Nuclear Medicine, Beijing Anzhen Hospital, Capital Medical University, No. 2 Anzhen Road, Chaoyang District, Beijing, 100029, China.,Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
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21
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Li X, Rosenkrans ZT, Wang J, Cai W. PET imaging of macrophages in cardiovascular diseases. Am J Transl Res 2020; 12:1491-1514. [PMID: 32509158 PMCID: PMC7270023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 03/14/2020] [Indexed: 06/11/2023]
Abstract
Cardiovascular diseases (CVDs) have been the leading cause of death in United States. While tremendous progress has been made for treating CVDs over the year, the high prevalence and substantial medical costs requires the necessity for novel methods for the early diagnosis and treatment monitoring of CVDs. Macrophages are a promising target due to its crucial role in the progress of CVDs (atherosclerosis, myocardial infarction and inflammatory cardiomyopathies). Positron emission tomography (PET) is a noninvasive imaging technique with high sensitivity and provides quantitive functional information of the macrophages in CVDs. Although 18F-FDG can be taken up by active macrophages, the PET imaging tracer is non-specific and susceptible to blood glucose levels. Thus, developing more specific PET tracers will help us understand the role of macrophages in CVDs. Moreover, macrophage-targeted PET imaging will further improve the diagnosis, treatment monitoring, and outcome prediction for patients with CVDs. In this review, we summarize various targets-based tracers for the PET imaging of macrophages in CVDs and highlight research gaps to advise future directions.
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Affiliation(s)
- Xiang Li
- Department of Nuclear Medicine, Xijing Hospital, Fourth Military Medical UniversityXi’an 710032, Shaanxi, China
- Department of Radiology and Medical Physics, University of Wisconsin-MadisonMadison, WI 53705, USA
| | - Zachary T Rosenkrans
- Department of Pharmaceutical Sciences, University of Wisconsin-MadisonMadison, WI 53705, USA
| | - Jing Wang
- Department of Nuclear Medicine, Xijing Hospital, Fourth Military Medical UniversityXi’an 710032, Shaanxi, China
| | - Weibo Cai
- Department of Radiology and Medical Physics, University of Wisconsin-MadisonMadison, WI 53705, USA
- Department of Pharmaceutical Sciences, University of Wisconsin-MadisonMadison, WI 53705, USA
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22
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Jahandideh A, Uotila S, Ståhle M, Virta J, Li XG, Kytö V, Marjamäki P, Liljenbäck H, Taimen P, Oikonen V, Lehtonen J, Mäyränpää MI, Chen Q, Low PS, Knuuti J, Roivainen A, Saraste A. Folate Receptor β-Targeted PET Imaging of Macrophages in Autoimmune Myocarditis. J Nucl Med 2020; 61:1643-1649. [PMID: 32284397 DOI: 10.2967/jnumed.119.241356] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 02/26/2020] [Indexed: 12/12/2022] Open
Abstract
Currently available imaging techniques have limited specificity for the detection of active myocardial inflammation. Aluminum 18F-labeled 1,4,7-triazacyclononane-N,N',N″-triacetic acid conjugated folate (18F-FOL) is a PET tracer targeting folate receptor β (FR-β), which is expressed on activated macrophages at sites of inflammation. We evaluated 18F-FOL PET for the detection of myocardial inflammation in rats with autoimmune myocarditis and studied the expression of FR-β in human cardiac sarcoidosis specimens. Methods: Myocarditis was induced by immunizing rats (n = 18) with porcine cardiac myosin in complete Freund adjuvant. Control rats (n = 6) were injected with Freund adjuvant alone. 18F-FOL was intravenously injected, followed by imaging with a small-animal PET/CT scanner and autoradiography. Contrast-enhanced high-resolution CT or 18F-FDG PET images were used for coregistration. Rat tissue sections and myocardial autopsy samples from 6 patients with cardiac sarcoidosis were studied for macrophages and FR-β. Results: The myocardium of 10 of 18 immunized rats showed focal macrophage-rich inflammatory lesions, with FR-β expression occurring mainly in M1-polarized macrophages. PET images showed focal myocardial 18F-FOL uptake colocalizing with inflammatory lesions (SUVmean, 2.1 ± 1.1), whereas uptake in the remote myocardium of immunized rats and controls was low (SUVmean, 0.4 ± 0.2 and 0.4 ± 0.1, respectively; P < 0.01). Ex vivo autoradiography of tissue sections confirmed uptake of 18F-FOL in myocardial inflammatory lesions. Uptake of 18F-FOL in inflamed myocardium was efficiently blocked by a nonlabeled FR-β ligand folate glucosamine in vivo. The myocardium of patients with cardiac sarcoidosis showed many FR-β-positive macrophages in inflammatory lesions. Conclusion: In a rat model of autoimmune myocarditis, 18F-FOL shows specific uptake in inflamed myocardium containing macrophages expressing FR-β, which were also present in human cardiac sarcoid lesions. Imaging of FR-β expression is a potential approach for the detection of active myocardial inflammation.
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Affiliation(s)
- Arghavan Jahandideh
- Turku PET Centre, University of Turku, Turku, Finland.,Turku PET Centre, Turku University Hospital, Turku, Finland
| | - Sauli Uotila
- Turku PET Centre, University of Turku, Turku, Finland
| | - Mia Ståhle
- Turku PET Centre, University of Turku, Turku, Finland
| | - Jenni Virta
- Turku PET Centre, University of Turku, Turku, Finland
| | - Xiang-Guo Li
- Turku PET Centre, University of Turku, Turku, Finland.,Turku PET Centre, Åbo Akademi University, Turku, Finland
| | - Ville Kytö
- Heart Center, Turku University Hospital and University of Turku, Turku, Finland
| | | | - Heidi Liljenbäck
- Turku PET Centre, University of Turku, Turku, Finland.,Turku Center for Disease Modeling, University of Turku, Turku, Finland
| | - Pekka Taimen
- Institute of Biomedicine, University of Turku and Department of Pathology, Turku University Hospital, Turku, Finland
| | - Vesa Oikonen
- Turku PET Centre, University of Turku, Turku, Finland
| | - Jukka Lehtonen
- Heart and Lung Center, Helsinki University and Helsinki University Hospital, Helsinki, Finland
| | - Mikko I Mäyränpää
- Pathology, Helsinki University and Helsinki University Hospital, Helsinki, Finland; and
| | - Qingshou Chen
- Department of Chemistry, Purdue University, West Lafayette, Indiana
| | - Philip S Low
- Department of Chemistry, Purdue University, West Lafayette, Indiana
| | - Juhani Knuuti
- Turku PET Centre, University of Turku, Turku, Finland.,Turku PET Centre, Turku University Hospital, Turku, Finland
| | - Anne Roivainen
- Turku PET Centre, University of Turku, Turku, Finland.,Turku PET Centre, Turku University Hospital, Turku, Finland.,Turku Center for Disease Modeling, University of Turku, Turku, Finland
| | - Antti Saraste
- Turku PET Centre, University of Turku, Turku, Finland .,Turku PET Centre, Turku University Hospital, Turku, Finland.,Heart Center, Turku University Hospital and University of Turku, Turku, Finland
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