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Chisholm TS, Hunter CA. A closer look at amyloid ligands, and what they tell us about protein aggregates. Chem Soc Rev 2024; 53:1354-1374. [PMID: 38116736 DOI: 10.1039/d3cs00518f] [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: 12/21/2023]
Abstract
The accumulation of amyloid fibrils is characteristic of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease. Detecting these fibrils with fluorescent or radiolabelled ligands is one strategy for diagnosing and better understanding these diseases. A vast number of amyloid-binding ligands have been reported in the literature as a result. To obtain a better understanding of how amyloid ligands bind, we have compiled a database of 3457 experimental dissociation constants for 2076 unique amyloid-binding ligands. These ligands target Aβ, tau, or αSyn fibrils, as well as relevant biological samples including AD brain homogenates. From this database significant variation in the reported dissociation constants of ligands was found, possibly due to differences in the morphology of the fibrils being studied. Ligands were also found to bind to Aβ(1-40) and Aβ(1-42) fibrils with similar affinities, whereas a greater difference was found for binding to Aβ and tau or αSyn fibrils. Next, the binding of ligands to fibrils was shown to be largely limited by the hydrophobic effect. Some Aβ ligands do not fit into this hydrophobicity-limited model, suggesting that polar interactions can play an important role when binding to this target. Finally several binding site models were outlined for amyloid fibrils that describe what ligands target what binding sites. These models provide a foundation for interpreting and designing site-specific binding assays.
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Affiliation(s)
- Timothy S Chisholm
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1 EW, UK.
| | - Christopher A Hunter
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1 EW, UK.
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Liang C, Nguyen GA, Danh TB, Sandhu AK, Melkonyan LL, Syed AU, Mukherjee J. Abnormal [ 18 F]NIFENE binding in transgenic 5xFAD mouse model of Alzheimer's disease: In vivo PET/CT imaging studies of α4β2* nicotinic acetylcholinergic receptors and in vitro correlations with Aβ plaques. Synapse 2023; 77:e22265. [PMID: 36749986 PMCID: PMC10148164 DOI: 10.1002/syn.22265] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/31/2023] [Accepted: 02/02/2023] [Indexed: 02/09/2023]
Abstract
Since cholinergic dysfunction has been implicated in Alzheimer's disease (AD), the effects of Aβ plaques on nicotinic acetylcholine receptors (nAChRs) α4β2* subtype were studied using the transgenic 5xFAD mouse model of AD. Using the PET radiotracer [18 F]nifene for α4β2* nAChRs, in vitro autoradiography and in vivo PET/CT studies in 5xFAD mice were carried out and compared with wild-type (C57BL/6) mice. Ratios of [18 F]nifene binding in brain regions versus cerebellum (CB) in 5xFAD mice brains were for thalamus (TH) = 17, hippocampus-subiculum = 7, frontal cortex (FC) = 5.5, and striatum = 4.7. [125 I]IBETA and immunohistochemistry (IHC) in 5xFAD brain slices confirmed Aβ plaques. Nicotine and acetylcholine displaced [18 F]nifene in 5xFAD mice (IC50 nicotine = 31-73 nM; ACh = 38-83 nM) and C57BL/6 (IC50 nicotine = 16-18 nM; ACh = 34-55 nM). Average [18 F]nifene SUVR (CB as reference) in 5xFAD mice was significantly higher in FC = 3.04 compared to C57BL/6 mice FC = 1.92 (p = .001), whereas TH difference between 5xFAD mice (SUVR = 2.58) and C57BL/6 mice (SUVR = 2.38) was not significant. Nicotine-induced dissociation half life (t1/2 ) of [18 F]nifene for TH were 37 min for 5xFAD mice and 26 min for C57BL/6 mice. Dissociation half life for FC in C57BL/6 mice was 77 min , while no dissociation of [18 F]nifene occurred in the medial prefrontal cortex (mFC) of 5xFAD mice. Coregistration of [18 F]nifene PET with MR suggested that the mPFC, and anterior cingulate (AC) regions exhibited high uptake in 5xFAD mice compared to C57BL/6 mice. Ex vivo [18 F]nifene and in vitro [125 I]IBETA Aβ plaque autoradiography after in vivo PET/CT scan of 5xFAD mouse brain were moderately correlated (r2 = 0.68). In conclusion, 5xFAD mice showed increased non-displaceable [18 F]nifene binding in mPFC.
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Affiliation(s)
- Christopher Liang
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, California, USA
| | - Grace A Nguyen
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, California, USA
| | - Tram B Danh
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, California, USA
| | - Anoopraj K Sandhu
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, California, USA
| | - Lusine L Melkonyan
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, California, USA
| | - Amina U Syed
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, California, USA
| | - Jogeshwar Mukherjee
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, California, USA
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Reddy TT, Iguban MH, Melkonyan LL, Shergill J, Liang C, Mukherjee J. Development of [ 124/125I]IAZA as a New Proteinopathy Imaging Agent for Alzheimer's Disease. Molecules 2023; 28:molecules28020865. [PMID: 36677925 PMCID: PMC9863004 DOI: 10.3390/molecules28020865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/08/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Radioiodinated imaging agents for Aβ amyloid plaque imaging in Alzheimer’s disease (AD) patients have not been actively pursued. Our previous studies employed the “diaza” derivatives [11C]TAZA and [18F]flotaza in order to develop successful positron emission tomography (PET) imaging agents for Aβ plaques. There is a need for radioiodinated imaging agents for Aβ plaques for single photon emission computed tomography (SPECT) and PET imaging. We report our findings on the preparation of [124/125I]IAZA, a “diaza” analog of [11C]TAZA and [18F]flotaza, and the evaluation of binding to Aβ plaques in the postmortem human AD brain. The binding affinity of IAZA for Aβ plaques was Ki = 10.9 nM with weak binding affinity for neurofibrillary tangles (Ki = 3.71 μM). Both [125I]IAZA and [124I]IAZA were produced in >25% radiochemical yield and >90% radiochemical purity. In vitro binding of [125I]IAZA and [124I]IAZA in postmortem human AD brains was higher in gray matter containing Aβ plaques compared to white matter (ratio of gray to white matter was >7). Anti-Aβ immunostaining strongly correlated with [124/125I]IAZA in postmortem AD human brains. The binding of [124/125I]IAZA in postmortem human AD brains was displaced by the known Aβ plaque imaging agents. Thus, radiolabeled [124/123I]IAZA may potentially be a useful PET or SPECT radioligand for Aβ plaques in brain imaging studies.
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[ 124I]IBETA: A New Aβ Plaque Positron Emission Tomography Imaging Agent for Alzheimer's Disease. Molecules 2022; 27:molecules27144552. [PMID: 35889425 PMCID: PMC9319930 DOI: 10.3390/molecules27144552] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 11/16/2022] Open
Abstract
Several fluorine-18-labeled PET β-amyloid (Aβ) plaque radiotracers for Alzheimer’s disease (AD) are in clinical use. However, no radioiodinated imaging agent for Aβ plaques has been successfully moved forward for either single-photon emission computed tomography (SPECT) or positron emission tomography (PET) imaging. Radioiodinated pyridyl benzofuran derivatives for the SPECT imaging of Aβ plaques using iodine-123 and iodine-125 are being pursued. In this study, we assess the iodine-124 radioiodinated pyridyl benzofuran derivative 5-(5-[124I]iodobenzofuran-2-yl)-N,N-dimethylpyridin-2-amine ([124I]IBETA) (Ki = 2.36 nM) for utilization in PET imaging for Aβ plaques. We report our findings on the radioiododestannylation reaction used to prepare [124/125I]IBETA and evaluate its binding to Aβ plaques in a 5 × FAD mouse model and postmortem human AD brain. Both [125I]IBETA and [124I]IBETA are produced in >25% radiochemical yield and >85% radiochemical purity. The in vitro binding of [125I]IBETA and [124I]IBETA in transgenic 5 × FAD mouse model for Aβ plaques was high in the frontal cortex, anterior cingulate, thalamus, and hippocampus, which are regions of high Aβ accumulation, with very little binding in the cerebellum (ratio of brain regions to cerebellum was >5). The in vitro binding of [125I]IBETA and [124I]IBETA in postmortem human AD brains was higher in gray matter containing Aβ plaques compared to white matter (ratio of gray to white matter was >5). Anti-Aβ immunostaining strongly correlated with [124/125I]IBETA regional binding in both the 5 × FAD mouse and postmortem AD human brains. The binding of [124/125I]IBETA in 5 × FAD mouse and postmortem human AD brains was displaced by the known Aβ plaque imaging agent, Flotaza. Preliminary PET/CT studies of [124I]IBETA in the 5 × FAD mouse model suggested [124I]IBETA was relatively stable in vivo with a greater localization of [124I]IBETA in the brain regions with a high concentration of Aβ plaques. Some deiodination was observed at later time points. Therefore, [124I]IBETA may potentially be a useful PET radioligand for Aβ plaques in brain studies.
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NRM 2021 Abstract Booklet. J Cereb Blood Flow Metab 2021; 41:11-309. [PMID: 34905986 PMCID: PMC8851538 DOI: 10.1177/0271678x211061050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Kaur H, Felix MR, Liang C, Mukherjee J. Development and evaluation of [ 18F]Flotaza for Aβ plaque imaging in postmortem human Alzheimer's disease brain. Bioorg Med Chem Lett 2021; 46:128164. [PMID: 34082067 PMCID: PMC8379902 DOI: 10.1016/j.bmcl.2021.128164] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 05/20/2021] [Accepted: 05/27/2021] [Indexed: 11/30/2022]
Abstract
Positron emission tomographic (PET) studies of amyloid β (Aβ) accumulation in Alzheimer's disease (AD) have shown clinical utility. The aim of this study was to develop and evaluate the effectiveness of a new fluorine-18 radiotracer [18F]Flotaza (2-{2-[2-[18F]fluoroethoxy]ethoxy}ethoxy)-4'-N,N-dimethylaminoazobenzene), for Aβ plaque imaging. Nucleophilic [18F]fluoride was used in a one-step radiosynthesis for [18F]flotaza. Using post mortem human AD brain tissues consisting of anterior cingulate (AC) and corpus callosum (CC), binding affinity of Flotaza, Ki = 1.68 nM for human Aβ plaques and weak (>10-5 M) for Tau protein. Radiosynthesis of [18F]Flotaza was very efficient in high radiochemical yields (>25%) with specific activities >74 GBq/μmol. Brain slices from all AD subjects were positively immunostained with anti-Aβ. Ratio of [18F]Flotaza in gray matter AC to white matter CC was >100 in all the 6 subjects. Very little white matter binding was seen. [18F]Flotaza binding in AC strongly correlated with anti-Aβ immunostains. [18F]Flotaza is therefore a suitable fluorine-18 PET radiotracer for PET imaging studies of human Aβ plaques.
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Affiliation(s)
- Harsimran Kaur
- Preclinical Imaging, Department of Radiological Sciences, University of California, Irvine 92697, USA
| | - Megan R Felix
- Preclinical Imaging, Department of Radiological Sciences, University of California, Irvine 92697, USA
| | - Christopher Liang
- Preclinical Imaging, Department of Radiological Sciences, University of California, Irvine 92697, USA
| | - Jogeshwar Mukherjee
- Preclinical Imaging, Department of Radiological Sciences, University of California, Irvine 92697, USA.
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Mukherjee J, Liang C, Patel KK, Lam PQ, Mondal R. Development and evaluation of [ 125 I]IPPI for Tau imaging in postmortem human Alzheimer's disease brain. Synapse 2020; 75:e22183. [PMID: 32722889 DOI: 10.1002/syn.22183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/17/2020] [Accepted: 07/18/2020] [Indexed: 01/23/2023]
Abstract
OBJECTIVE Alzheimer's disease (AD) is a neurodegenerative disease characterized by aggregation of Tau protein into paired helical filaments causing neurofibrillary tangles (NFT) in the brain. The aim of this study was to develop and evaluate the effectiveness of a novel radioiodinated tracer, 6-[125 I]iodo-3-(1H-pyrrolo[2,3-c]pyridine-1-yl)isoquinoline ([125 I]IPPI), for binding to Tau protein (Ki = 0.75 nM) in postmortem human brain (AD and cognitively normal (CN). METHODS Radiosynthesis of [125 I]IPPI was carried out by radioiododestannylation and purified chromatographically. Computational modeling studies of IPPI and MK-6240 binding on Tau fibril were evaluated. In vitro autoradiography studies were carried out with [3 H]PIB for Aβ plaques and [125 I]IPPI for Tau in AD and CN brains and evaluate drug effects. RESULTS [125 I]IPPI was produced in >95% purity. Molecular modeling of IPPI revealed binding energies of IPPI (-7.8, -8.1, -8.2, -7.5 Kcal/mol) at the four sites were comparable to MK-6240 (-8.7, -8.5, -8.3, -7.5 Kcal/mol). Ratio of average grey matter (GM) [125 I]IPPI in AD versus CN was found to be 7.31 (p = .07) and AD GM/ white matter (WM) = 4.35 (p = .09). Ratio of average GM/WM [125 I]IPPI in CN was 1.21. Binding of [125 I]IPPI correlated with the presence of Tau, confirmed by anti-Tau Dako A0024. Specifically bound [125 I]IPPI to Tau in AD brains was displaced by MK-6240 and IPPI (>90%). Monoamine oxidase inhibitors (MAO) inhibitors deprenyl and clorgyline effected [125 I]IPPI binding at >1 µM concentrations. CONCLUSION [125 I]IPPI exhibited high binding in human AD frontal cortex and anterior cingulate and is a suitable radioiodinated ligand for Tau imaging.
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Affiliation(s)
- Jogeshwar Mukherjee
- Preclinical Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA
| | - Christopher Liang
- Preclinical Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA
| | - Krystal K Patel
- Preclinical Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA
| | - Phuc Q Lam
- Preclinical Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA
| | - Rommani Mondal
- Preclinical Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA
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Gu J, Wang X, Yang H, Li H, Wang J. Preclinical in vivo imaging for brown adipose tissue. Life Sci 2020; 249:117500. [PMID: 32147430 DOI: 10.1016/j.lfs.2020.117500] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 02/23/2020] [Accepted: 03/02/2020] [Indexed: 12/22/2022]
Abstract
Brown adipose tissue (BAT) has multiple functions in the human body, including the production of heat and increasing energy consumption. However, BAT is also related to many kinds of diseases, such as obesity and metabolic disorders. The progression of such diseases occurs at the cellular level, and thus, imaging techniques could prove greatly beneficial for determining optimal therapeutic regimens. Currently, positron-emission tomography (PET) is considered to be the gold standard for assessing the function of activated BAT. However, PET also has inherent disadvantages, and, thus, recent efforts have been focused on exploring, and potentially developing, new imaging techniques to better observe BAT and evaluate its metabolic function. Researchers have already achieved promising success with computed tomography, magnetic resonance approaches, ultrasound, new tracers for use in PET, and other imaging techniques through in vivo and in vitro animal experiments. Since, these studies have shown that BAT may serve as an effective therapeutic target for treatment of metabolic dysfunction diseases, the development of an efficient in vivo BAT imaging technique that is applicable to humans will prove to be of great clinical value. In this review, classical PET imaging technique is highlighted as well as the current status of preclinical imaging methods developed for BAT examination.
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Affiliation(s)
- Jiaojiao Gu
- Department of Ultrasound, Shengjing Hospital of China Medical University, Shengjing Hospital, No. 36, Sanhao Street, Heping District, Shenyang, Liaoning, China
| | - Xinlu Wang
- Department of Ultrasound, Shengjing Hospital of China Medical University, Shengjing Hospital, No. 36, Sanhao Street, Heping District, Shenyang, Liaoning, China.
| | - Hua Yang
- Department of Ultrasound, Shengjing Hospital of China Medical University, Shengjing Hospital, No. 36, Sanhao Street, Heping District, Shenyang, Liaoning, China
| | - He Li
- Department of Ultrasound, Shengjing Hospital of China Medical University, Shengjing Hospital, No. 36, Sanhao Street, Heping District, Shenyang, Liaoning, China
| | - Jie Wang
- Department of Ultrasound, Shengjing Hospital of China Medical University, Shengjing Hospital, No. 36, Sanhao Street, Heping District, Shenyang, Liaoning, China
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Samra GK, Dang K, Ho H, Baranwal A, Mukherjee J. Dual targeting agents for Aβ plaque/P-glycoprotein and Aβ plaque/nicotinic acetylcholine α4β2* receptors-potential approaches to facilitate Aβ plaque removal in Alzheimer's disease brain. Med Chem Res 2018; 27:1634-1646. [PMID: 29937677 PMCID: PMC6013267 DOI: 10.1007/s00044-018-2178-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 03/31/2018] [Indexed: 12/28/2022]
Abstract
Alzheimer's disease (AD) affects 10% of people older than 65 and is characterized by a progressive loss of cognitive function with an abnormal accumulation of amyloid β (Aβ ) plaques and neurofibrillary tangles (NFT) in the brain. Efforts to reduce brain Aβ plaques continue to be investigated as a therapeutic approach for AD. We report here development of dual targeting agents with affinity for Aβ plaque/P-glycoprotein (Pgp) and Aβ plaque/α4β 2* nicotinic acetylcholine receptors (nAChR). These novel dual agents may be able to efflux Aβ plaques via the paravascular (glymphatic) pathways. Ferulic acid (FA), ferulic acid ethyl ester (FAEE), and curcumin (CUR) were used for Aβ plaques, fexofenadine (FEX) was used as substrate for Pgp and nifrolidine (NIF) was used for α4β 2* nAChRs. Aβ plaque/α4β 2* nAChR dual agent, FA-NIF (GKS-007) exhibited IC50 = 3-6 nM for α4β 2* nAChRs in [3H]cytisine-radiolabeled thalamus and frontal cortex in rat brain slices. In postmortem human AD frontal cortex, Aβ plaques labeled with [3H]PIB, FEX-CUR showed a 35% reduction in gray matter (GM)/white matter (WM) [3H]PIB binding, while CUR alone showed a 50% reduction. In vivo biodistribution studies are required of the Aβ-Pgp and Aβ-α4β 2* nAChRs dual targeting agents in order to evaluate their potential as therapeutic approaches for reducing brain Aβ plaques.
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Affiliation(s)
- Gurleen K Samra
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, CA 92697, USA
| | - Kenneth Dang
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, CA 92697, USA
| | - Heather Ho
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, CA 92697, USA
| | - Aparna Baranwal
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, CA 92697, USA
| | - Jogeshwar Mukherjee
- Preclinical Imaging, Department of Radiological Sciences, University of California-Irvine, Irvine, CA 92697, USA
- Department of Biomedical Engineering, University of California-Irvine, Irvine, CA 92697, USA
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Zhang XY, Yang ZL, Lu GM, Yang GF, Zhang LJ. PET/MR Imaging: New Frontier in Alzheimer's Disease and Other Dementias. Front Mol Neurosci 2017; 10:343. [PMID: 29163024 PMCID: PMC5672108 DOI: 10.3389/fnmol.2017.00343] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 10/10/2017] [Indexed: 12/31/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia; a progressive neurodegenerative disease that currently lacks an effective treatment option. Early and accurate diagnosis, in addition to quick elimination of differential diagnosis, allows us to provide timely treatments that delay the progression of AD. Imaging plays an important role for the early diagnosis of AD. The newly emerging PET/MR imaging strategies integrate the advantages of PET and MR to diagnose and monitor AD. This review introduces the development of PET/MR imaging systems, technical considerations of PET/MR imaging, special considerations of PET/MR in AD, and the system's potential clinical applications and future perspectives in AD.
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Affiliation(s)
- Xin Y Zhang
- Medical Imaging Center, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Zhen L Yang
- Medical Imaging Center, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Guang M Lu
- Medical Imaging Center, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Gui F Yang
- Medical Imaging Center, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Long J Zhang
- Medical Imaging Center, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
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Dupont AC, Santiago Ribeiro MJ, Guilloteau D, Arlicot N. β-amyloid PET neuroimaging: A review of radiopharmaceutical development. MEDECINE NUCLEAIRE-IMAGERIE FONCTIONNELLE ET METABOLIQUE 2017. [DOI: 10.1016/j.mednuc.2016.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Mukherjee J, Baranwal A, Schade KN. Classification of Therapeutic and Experimental Drugs for Brown Adipose Tissue Activation: Potential Treatment Strategies for Diabetes and Obesity. Curr Diabetes Rev 2016; 12:414-428. [PMID: 27183844 PMCID: PMC5425649 DOI: 10.2174/1573399812666160517115450] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 05/06/2016] [Accepted: 05/12/2016] [Indexed: 01/23/2023]
Abstract
OBJECTIVE Increasing efforts are being made towards pharmacologic activation of brown adipose tissue (BAT) in animals and humans for potential use in the treatment of obesity and diabetes. We and others have reported a number of animal studies using either experimental or therapeutic drugs. There are now efforts to translate these findings to human studies. The goal of this review is to evaluate the various drugs currently being used that have the potential for BAT activation. METHODS Drugs were classified into 4 classes based on their mechanism of action. Class 1 drugs include the use of β3 adrenoceptor agonists for BAT activation. Class 2 drugs include drugs that affect norepinephrine levels and activate BAT with the potential of reducing obesity. Class 3 includes activators of peroxisome proliferator-activated receptor-γ in pursuit of lowering blood sugar, weight loss and diabetes and finally Class 4 includes natural products and other emerging drugs with limited information on BAT activation and their effects on diabetes and weight loss. RESULTS Class 1 drugs are high BAT activators followed by Class 2 and 3. Some of these drugs have now been extended to diabetes and obesity animal models and human BAT studies. Drugs in Class 3 are used clinically for Type 2 diabetes, but the extent of BAT involvement is unclear. CONCLUSION Further studies on the efficacy of these drugs in diabetes and measuring their effects on BAT activation using noninvasive imaging will help in establishing a clinical role of BAT.
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Affiliation(s)
- Jogeshwar Mukherjee
- B140 Medical Sciences, Department of Radiological Sciences, University of California - Irvine, Irvine, CA 92697-5000, USA.
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