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Naproxen as a potential candidate for promoting rivastigmine anti-Alzheimer activity against aluminum chloride-prompted Alzheimer's-like disease in rats; neurogenesis and apoptosis modulation as a possible underlying mechanism. Eur J Pharmacol 2022; 915:174695. [PMID: 34914971 DOI: 10.1016/j.ejphar.2021.174695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/29/2021] [Accepted: 12/07/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND AND AIM Alzheimer's disease (AD) is one of the leading causes of dependence and disability among the elderly worldwide. The traditional anti-Alzheimer medication, rivastigmine, one of the cholinesterase inhibitors (ChEIs), fails to achieve a definitive cure. We tested the hypothesis that naproxen administration to the rivastigmine-treated aluminum chloride (AlCl3) Alzheimer's rat model could provide an additive neuroprotective effect compared to rivastigmine alone. MATERIALS AND METHODS The studied groups were control (Cont), AlCl3 treated (Al), rivastigmine treated (RIVA), naproxen treated (Napro), and combined rivastigmine and naproxen treated (RIVA + Napro). Rats' memory, spatial learning, and cognitive behavior were assessed followed by evaluation of hippocampal acetylcholinesterase (AChE) activity. Hippocampal and cerebellar histopathology were thoroughly examined. Activated caspase-3 and the neuroepithelial stem cells marker; nestin expressions were immunohistochemically assayed. RESULTS AD rats displayed significantly impaired memory and cognitive function, augmented hippocampal AChE activity; massive neurodegeneration associated with enhanced astrogliosis, apoptosis, and impaired neurogenesis. Except for the enhancement of neurogenesis and suppression of apoptosis, the combination therapy had no additional neuroprotective benefit over rivastigmine-only therapy. CONCLUSION Naproxen's efficacy was established by its ability to function at the cellular level, improved neurogenesis, and decreased, apoptosis without having an additional mitigating impact on cognitive impairment in rivastigmine-treated AD rats.
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2
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Cao L, Kong Y, Ji B, Ren Y, Guan Y, Ni R. Positron Emission Tomography in Animal Models of Tauopathies. Front Aging Neurosci 2022; 13:761913. [PMID: 35082657 PMCID: PMC8784812 DOI: 10.3389/fnagi.2021.761913] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 11/30/2021] [Indexed: 12/18/2022] Open
Abstract
The microtubule-associated protein tau (MAPT) plays an important role in Alzheimer's disease and primary tauopathy diseases. The abnormal accumulation of tau contributes to the development of neurotoxicity, inflammation, neurodegeneration, and cognitive deficits in tauopathy diseases. Tau synergically interacts with amyloid-beta in Alzheimer's disease leading to detrimental consequence. Thus, tau has been an important target for therapeutics development for Alzheimer's disease and primary tauopathy diseases. Tauopathy animal models recapitulating the tauopathy such as transgenic, knock-in mouse and rat models have been developed and greatly facilitated the understanding of disease mechanisms. The advance in PET and imaging tracers have enabled non-invasive detection of the accumulation and spread of tau, the associated microglia activation, metabolic, and neurotransmitter receptor alterations in disease animal models. In vivo microPET studies on mouse or rat models of tauopathy have provided significant insights into the phenotypes and time course of pathophysiology of these models and allowed the monitoring of treatment targeting at tau. In this study, we discuss the utilities of PET and recently developed tracers for evaluating the pathophysiology in tauopathy animal models. We point out the outstanding challenges and propose future outlook in visualizing tau-related pathophysiological changes in brain of tauopathy disease animal models.
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Affiliation(s)
- Lei Cao
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Changes Technology Corporation Ltd., Shanghai, China
| | - Yanyan Kong
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Bin Ji
- Department of Radiopharmacy and Molecular Imaging, School of Pharmacy, Fudan University, Shanghai, China
| | - Yutong Ren
- Guangdong Robotics Association, Guangzhou, China
| | - Yihui Guan
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Ruiqing Ni
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Institute for Biomedical Engineering, ETH Zurich and University of Zurich, Zurich, Switzerland
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3
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Ni R, Nitsch RM. Recent Developments in Positron Emission Tomography Tracers for Proteinopathies Imaging in Dementia. Front Aging Neurosci 2022; 13:751897. [PMID: 35046791 PMCID: PMC8761855 DOI: 10.3389/fnagi.2021.751897] [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: 08/02/2021] [Accepted: 11/17/2021] [Indexed: 12/15/2022] Open
Abstract
An early detection and intervention for dementia represent tremendous unmet clinical needs and priorities in society. A shared feature of neurodegenerative diseases causing dementia is the abnormal accumulation and spreading of pathological protein aggregates, which affect the selective vulnerable circuit in a disease-specific pattern. The advancement in positron emission tomography (PET) biomarkers has accelerated the understanding of the disease mechanism and development of therapeutics for Alzheimer's disease and Parkinson's disease. The clinical utility of amyloid-β PET and the clinical validity of tau PET as diagnostic biomarker for Alzheimer's disease continuum have been demonstrated. The inclusion of biomarkers in the diagnostic criteria has introduced a paradigm shift that facilitated the early and differential disease diagnosis and impacted on the clinical management. Application of disease-modifying therapy likely requires screening of patients with molecular evidence of pathological accumulation and monitoring of treatment effect assisted with biomarkers. There is currently still a gap in specific 4-repeat tau imaging probes for 4-repeat tauopathies and α-synuclein imaging probes for Parkinson's disease and dementia with Lewy body. In this review, we focused on recent development in molecular imaging biomarkers for assisting the early diagnosis of proteinopathies (i.e., amyloid-β, tau, and α-synuclein) in dementia and discussed future perspectives.
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Affiliation(s)
- Ruiqing Ni
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Institute for Biomedical Engineering, ETH & University of Zurich, Zurich, Switzerland
| | - Roger M. Nitsch
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
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4
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Ni R. Positron Emission Tomography in Animal Models of Alzheimer's Disease Amyloidosis: Translational Implications. Pharmaceuticals (Basel) 2021; 14:1179. [PMID: 34832961 PMCID: PMC8623863 DOI: 10.3390/ph14111179] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/13/2021] [Accepted: 11/15/2021] [Indexed: 12/30/2022] Open
Abstract
Animal models of Alzheimer's disease amyloidosis that recapitulate cerebral amyloid-beta pathology have been widely used in preclinical research and have greatly enabled the mechanistic understanding of Alzheimer's disease and the development of therapeutics. Comprehensive deep phenotyping of the pathophysiological and biochemical features in these animal models is essential. Recent advances in positron emission tomography have allowed the non-invasive visualization of the alterations in the brain of animal models and in patients with Alzheimer's disease. These tools have facilitated our understanding of disease mechanisms and provided longitudinal monitoring of treatment effects in animal models of Alzheimer's disease amyloidosis. In this review, we focus on recent positron emission tomography studies of cerebral amyloid-beta accumulation, hypoglucose metabolism, synaptic and neurotransmitter receptor deficits (cholinergic and glutamatergic system), blood-brain barrier impairment, and neuroinflammation (microgliosis and astrocytosis) in animal models of Alzheimer's disease amyloidosis. We further propose the emerging targets and tracers for reflecting the pathophysiological changes and discuss outstanding challenges in disease animal models and future outlook in the on-chip characterization of imaging biomarkers towards clinical translation.
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Affiliation(s)
- Ruiqing Ni
- Institute for Biomedical Engineering, ETH & University of Zurich, 8093 Zurich, Switzerland;
- Institute for Regenerative Medicine, University of Zurich, 8952 Zurich, Switzerland
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5
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Focused ultrasound for opening blood-brain barrier and drug delivery monitored with positron emission tomography. J Control Release 2020; 324:303-316. [DOI: 10.1016/j.jconrel.2020.05.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 12/14/2022]
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6
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A Curcumin Analog Exhibits Multiple Biologic Effects on the Pathogenesis of Alzheimer's Disease and Improves Behavior, Inflammation, and β-Amyloid Accumulation in a Mouse Model. Int J Mol Sci 2020; 21:ijms21155459. [PMID: 32751716 PMCID: PMC7432838 DOI: 10.3390/ijms21155459] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/06/2020] [Accepted: 07/28/2020] [Indexed: 12/19/2022] Open
Abstract
Drugs for the treatment of Alzheimer’s disease (AD) are in urgent demand due to the unmet need and the social burden associated with the disease. Curcumin has been historically considered as a beneficial product for anti-aging and AD. However, many efforts to develop curcumin for clinical use are hindered mainly due to its poor bioavailability. Recent development in drug delivery and structural design has resolved these issues. In this study, we identified a small molecule, TML-6, as a potential drug candidate for AD through screening a panel of curcumin derivatives using six biomarker platforms related to aging biology and AD pathogenesis. The structural modification of TML-6 is designed to improve the stability and metabolism of curcumin. Cell biological studies demonstrated that TML-6 could inhibit the synthesis of the β-amyloid precursor protein and β-amyloid (Aβ), upregulate Apo E, suppress NF-κB and mTOR, and increase the activity of the anti-oxidative Nrf2 gene. In the 3x-Tg AD animal model, TML-6 treatment resulted in significant improvement in learning, suppression of the microglial activation marker Iba-1, and reduction in Aβ in the brain. Although TML-6 exhibited a greater improvement in bioavailability as compared to curcumin, formulation optimization and toxicological studies are under development to assure its druggability. Taken together, TML-6 meets the current strategy to develop therapeutics for AD, targeting the combination of the Aβ cascade and aging-related biology processes.
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7
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Son HJ, Jeong YJ, Yoon HJ, Lee SY, Choi GE, Park JA, Kim MH, Lee KC, Lee YJ, Kim MK, Cho K, Kang DY. Assessment of brain beta-amyloid deposition in transgenic mouse models of Alzheimer's disease with PET imaging agents 18F-flutemetamol and 18F-florbetaben. BMC Neurosci 2018; 19:45. [PMID: 30053803 PMCID: PMC6063010 DOI: 10.1186/s12868-018-0447-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 07/23/2018] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Although amyloid beta (Aβ) imaging is widely used for diagnosing and monitoring Alzheimer's disease in clinical fields, paralleling comparison between 18F-flutemetamol and 18F-florbetaben was rarely attempted in AD mouse model. We performed a comparison of Aβ PET images between 18F-flutemetamol and 18F-florbetaben in a recently developed APPswe mouse model, C57BL/6-Tg (NSE-hAPPsw) Korl. RESULTS After an injection (0.23 mCi) of 18F-flutemetamol and 18F-florbetaben at a time interval of 2-3 days, we compared group difference of SUVR and kinetic parameters between the AD (n = 7) and control (n = 7) mice, as well as between 18F-flutemetamol and 18F-florbetaben image. In addition, bio-distribution and histopathology were conducted. With visual image and VOI-based SUVR analysis, the AD group presented more prominent uptake than did the control group in both the 18F-florbetaben and 18F-flutemetamol images. With kinetic analysis, the 18F-florbetaben images showed differences in K1 and k4 between the AD and control groups, although 18F-flutemetamol images did not show significant difference. 18F-florbetaben images showed more prominent cortical uptake and matched well to the thioflavin S staining images than did the 18F-flutemetamol image. In contrast, 18F-flutemetamol images presented higher K1, k4, K1/k2 values than those of 18F-florbetaben images. Also, 18F-flutemetamol images presented prominent uptake in the bowel and bladder, consistent with higher bio-distribution in kidney, lung, blood and heart. CONCLUSIONS Compared with 18F-flutemetamol images, 18F-florbetaben images showed prominent visual uptake intensity, SUVR, and higher correlations with the pathology. In contrast, 18F-flutemetamol was more actively metabolized than was 18F-florbetaben (Son et al. in J Nucl Med 58(Suppl 1):S278, 2017].
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Affiliation(s)
- Hye Joo Son
- Department of Nuclear Medicine, Dong-A University Medical Center, Dong-A University College of Medicine, 26 Daesingongwon-ro, Seo-gu, Busan, 602-812 Korea
| | - Young Jin Jeong
- Department of Nuclear Medicine, Dong-A University Medical Center, Dong-A University College of Medicine, 26 Daesingongwon-ro, Seo-gu, Busan, 602-812 Korea
| | - Hyun Jin Yoon
- Department of Nuclear Medicine, Dong-A University Medical Center, Dong-A University College of Medicine, 26 Daesingongwon-ro, Seo-gu, Busan, 602-812 Korea
| | - Sang Yoon Lee
- Department of Nuclear Medicine, Dong-A University Medical Center, Dong-A University College of Medicine, 26 Daesingongwon-ro, Seo-gu, Busan, 602-812 Korea
| | - Go-Eun Choi
- Institute of Convergence Bio-Health, Dong-A University, Busan, Korea
| | - Ji-Ae Park
- Division of RI-Convergence Research, Korea Institute of Radiological and Medical Sciences, Seoul, Korea
| | - Min Hwan Kim
- Division of RI-Convergence Research, Korea Institute of Radiological and Medical Sciences, Seoul, Korea
| | - Kyo Chul Lee
- Division of RI-Convergence Research, Korea Institute of Radiological and Medical Sciences, Seoul, Korea
| | - Yong Jin Lee
- Division of RI-Convergence Research, Korea Institute of Radiological and Medical Sciences, Seoul, Korea
| | - Mun Ki Kim
- Pohang Center of Evolution of Biomaterials, Pohang Technopark, Pohang, Korea
| | - Kook Cho
- Institute of Convergence Bio-Health, Dong-A University, Busan, Korea
| | - Do-Young Kang
- Department of Nuclear Medicine, Dong-A University Medical Center, Dong-A University College of Medicine, 26 Daesingongwon-ro, Seo-gu, Busan, 602-812 Korea
- Institute of Convergence Bio-Health, Dong-A University, Busan, Korea
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8
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Malik R, Di J, Nair G, Attar A, Taylor K, Teng E, Klärner FG, Schrader T, Bitan G. Using Molecular Tweezers to Remodel Abnormal Protein Self-Assembly and Inhibit the Toxicity of Amyloidogenic Proteins. Methods Mol Biol 2018; 1777:369-386. [PMID: 29744849 DOI: 10.1007/978-1-4939-7811-3_24] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Molecular tweezers (MTs) are broad-spectrum inhibitors of abnormal protein self-assembly, which act by binding selectively to lysine and arginine residues. Through this unique mechanism of action, MTs inhibit formation of toxic oligomers and aggregates. Their efficacy and safety have been demonstrated in vitro, in cell culture, and in animal models. Here, we discuss the application of MTs in diverse in vitro and in vivo systems, the experimental details, the scope of their use, and the limitations of the approach. We also consider methods for administration of MTs in animal models to measure efficacy, pharmacokinetic, and pharmacodynamic parameters in proteinopathies.
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Affiliation(s)
- Ravinder Malik
- Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Jing Di
- Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Gayatri Nair
- Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Aida Attar
- Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA.,Brain Research Institute, University of California at Los Angeles, Los Angeles, CA, USA
| | - Karen Taylor
- Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Edmond Teng
- Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA.,Greater Los Angeles Healthcare System, Veterans Hospital, West Los Angeles, CA, USA
| | | | - Thomas Schrader
- Faculty of Chemistry, University of Duisburg-Essen, Essen, Germany
| | - Gal Bitan
- Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA. .,Brain Research Institute, University of California at Los Angeles, Los Angeles, CA, USA. .,Molecular Biology Institute, University of California at Los Angeles, Los Angeles, CA, USA.
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9
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Grant DA, Serpa R, Moattari CR, Brown A, Greco T, Prins ML, Teng E. Repeat Mild Traumatic Brain Injury in Adolescent Rats Increases Subsequent β-Amyloid Pathogenesis. J Neurotrauma 2017; 35:94-104. [PMID: 28728464 DOI: 10.1089/neu.2017.5042] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Single moderate-to-severe traumatic brain injuries (TBIs) may increase subsequent risk for neurodegenerative disease by facilitating β-amyloid (Aβ) deposition. However, the chronic effects on Aβ pathogenesis of repetitive mild TBIs (rTBI), which are common in adolescents and young adults, remain uncertain. We examined the effects of rTBI sustained during adolescence on subsequent deposition of Aβ pathology in a transgenic APP/PS1 rat model. Transgenic rats received sham or four individual mild TBIs (rTBIs) separated by either 24- or 72-h intervals at post-natal day 35 (before Aβ plaque deposition). Animals were euthanized at 12 months of age and underwent immunohistochemical analyses of Aβ plaque deposition. Significantly greater hippocampal Aβ plaque deposition was observed after rTBI separated by 24 h relative to rTBI separated by 72 h or sham injuries. These increases in hippocampal Aβ plaque load were driven by increases in both plaque number and size. Similar, though less-pronounced, effects were observed in extrahippocampal regions. Increases in Aβ plaque deposition were observed both ipsilaterally and contralaterally to the injury site and in both males and females. rTBIs sustained in adolescence can increase subsequent deposition of Aβ pathology, and these effects are critically dependent on interinjury interval.
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Affiliation(s)
- Daya A Grant
- 1 Department of Neurosurgery, UCLA , Los Angeles, California.,3 Interdeparmental Program for Neuroscience, UCLA , Los Angeles, California
| | - Rebecka Serpa
- 1 Department of Neurosurgery, UCLA , Los Angeles, California
| | - Cameron R Moattari
- 3 Interdeparmental Program for Neuroscience, UCLA , Los Angeles, California
| | - Ari Brown
- 1 Department of Neurosurgery, UCLA , Los Angeles, California
| | - Tiffany Greco
- 1 Department of Neurosurgery, UCLA , Los Angeles, California
| | - Mayumi L Prins
- 1 Department of Neurosurgery, UCLA , Los Angeles, California
| | - Edmond Teng
- 2 Department of Neurology, David Geffen School of Medicine at UCLA, UCLA , Los Angeles, California.,4 Veterans Affairs Greater Los Angeles Healthcare System , Los Angeles, California
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10
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Schrader T, Bitan G, Klärner FG. Molecular tweezers for lysine and arginine - powerful inhibitors of pathologic protein aggregation. Chem Commun (Camb) 2016; 52:11318-34. [PMID: 27546596 PMCID: PMC5026632 DOI: 10.1039/c6cc04640a] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Molecular tweezers represent the first class of artificial receptor molecules that have made the way from a supramolecular host to a drug candidate with promising results in animal tests. Due to their unique structure, only lysine and arginine are well complexed with exquisite selectivity by a threading mechanism, which unites electrostatic, hydrophobic and dispersive attraction. However, tweezer design must avoid self-dimerization, self-inclusion and external guest binding. Moderate affinities of molecular tweezers towards sterically well accessible basic amino acids with fast on and off rates protect normal proteins from potential interference with their biological function. However, the early stages of abnormal Aβ, α-synuclein, and TTR assembly are redirected upon tweezer binding towards the generation of amorphous non-toxic materials that can be degraded by the intracellular and extracellular clearance mechanisms. Thus, specific host-guest chemistry between aggregation-prone proteins and lysine/arginine binders rescues cell viability and restores animal health in models of AD, PD, and TTR amyloidosis.
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Affiliation(s)
- Thomas Schrader
- Faculty of Chemistry, University of Duisburg-Essen, Essen, Germany.
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11
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Bilousova T, Miller CA, Poon WW, Vinters HV, Corrada M, Kawas C, Hayden EY, Teplow DB, Glabe C, Albay R, Cole GM, Teng E, Gylys KH. Synaptic Amyloid-β Oligomers Precede p-Tau and Differentiate High Pathology Control Cases. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:185-98. [PMID: 26718979 DOI: 10.1016/j.ajpath.2015.09.018] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 08/28/2015] [Accepted: 09/01/2015] [Indexed: 01/03/2023]
Abstract
Amyloid-β (Aβ) and hyperphosphorylated tau (p-tau) aggregates form the two discrete pathologies of Alzheimer disease (AD), and oligomeric assemblies of each protein are localized to synapses. To determine the sequence by which pathology appears in synapses, Aβ and p-tau were quantified across AD disease stages in parietal cortex. Nondemented cases with high levels of AD-related pathology were included to determine factors that confer protection from clinical symptoms. Flow cytometric analysis of synaptosome preparations was used to quantify Aβ and p-tau in large populations of individual synaptic terminals. Soluble Aβ oligomers were assayed by a single antibody sandwich enzyme-linked immunosorbent assay. Total in situ Aβ was elevated in patients with early- and late-stage AD dementia, but not in high pathology nondemented controls compared with age-matched normal controls. However, soluble Aβ oligomers were highest in early AD synapses, and this assay distinguished early AD cases from high pathology controls. Overall, synapse-associated p-tau did not increase until late-stage disease in human and transgenic rat cortex, and p-tau was elevated in individual Aβ-positive synaptosomes in early AD. These results suggest that soluble oligomers in surviving neocortical synaptic terminals are associated with dementia onset and suggest an amyloid cascade hypothesis in which oligomeric Aβ drives phosphorylated tau accumulation and synaptic spread. These results indicate that antiamyloid therapies will be less effective once p-tau pathology is developed.
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Affiliation(s)
- Tina Bilousova
- University of California Los Angeles School of Nursing, Los Angeles, California; Mary S. Easton Center for Alzheimer's Research at the University of California Los Angeles, Los Angeles, California
| | - Carol A Miller
- Departments of Pathology, Neurology, and the Program in Neuroscience, University of Southern California Keck School of Medicine, Los Angeles, California
| | - Wayne W Poon
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, California
| | - Harry V Vinters
- Department of Neurology, University of California Los Angeles School of Medicine, Los Angeles, California; Department of Pathology and Laboratory Medicine, University of California Los Angeles School of Medicine, Los Angeles, California
| | - Maria Corrada
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, California; Department of Neurology, University of California Irvine, Irvine, California
| | - Claudia Kawas
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, California; Department of Neurology, University of California Irvine, Irvine, California; Department of Neurobiology & Behavior, University of California Irvine, Irvine, California
| | - Eric Y Hayden
- Mary S. Easton Center for Alzheimer's Research at the University of California Los Angeles, Los Angeles, California; Department of Neurology, University of California Los Angeles School of Medicine, Los Angeles, California
| | - David B Teplow
- Mary S. Easton Center for Alzheimer's Research at the University of California Los Angeles, Los Angeles, California; Department of Neurology, University of California Los Angeles School of Medicine, Los Angeles, California
| | - Charles Glabe
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California
| | - Ricardo Albay
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California
| | - Gregory M Cole
- Mary S. Easton Center for Alzheimer's Research at the University of California Los Angeles, Los Angeles, California; Department of Neurology, University of California Los Angeles School of Medicine, Los Angeles, California; Department of Medicine, University of California Los Angeles School of Medicine, Los Angeles, California; Geriatric Research, Education and Clinical Center, VA Greater Los Angeles Healthcare System, Los Angeles, California
| | - Edmond Teng
- Mary S. Easton Center for Alzheimer's Research at the University of California Los Angeles, Los Angeles, California; Department of Neurology, University of California Los Angeles School of Medicine, Los Angeles, California; Geriatric Research, Education and Clinical Center, VA Greater Los Angeles Healthcare System, Los Angeles, California
| | - Karen H Gylys
- University of California Los Angeles School of Nursing, Los Angeles, California; Mary S. Easton Center for Alzheimer's Research at the University of California Los Angeles, Los Angeles, California.
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12
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Deleye S, Waldron AM, Richardson JC, Schmidt M, Langlois X, Stroobants S, Staelens S. The Effects of Physiological and Methodological Determinants on 18F-FDG Mouse Brain Imaging Exemplified in a Double Transgenic Alzheimer Model. Mol Imaging 2016; 15:15/0/1536012115624919. [PMID: 27030402 PMCID: PMC5470082 DOI: 10.1177/1536012115624919] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 12/04/2015] [Indexed: 12/22/2022] Open
Abstract
Introduction: In this study, the influence of physiological determinants on 18F-fluoro-d-glucose (18F-FDG) brain uptake was evaluated in a mouse model of Alzheimer disease. Materials and Methods: TASTPM (Tg) and age-matched C57BL/6 J (WT) mice were fasted for 10 hours, while another group was fasted for 20 hours to evaluate the effect of fasting duration. The effect of repeatedly scanning was evaluated by scanning Tg and WT mice at days 1, 4, and 7. Brain 18F-FDG uptake was evaluated in the thalamus being the most indicative region. Finally, the cerebellum was tested as a reference region for the relative standard uptake value (rSUV). Results: When correcting the brain uptake for glucose, the effect of different fasting durations was attenuated and the anticipated hypometabolism in Tg mice was demonstrated. Also, with repeated scanning, the brain uptake values within a group and the hypometabolism of the Tg mice only remained stable over time when glucose correction was applied. Finally, hypometabolism was also observed in the cerebellum, yielding artificially higher rSUV values for Tg mice. Conclusion: Corrections for blood glucose levels have to be applied when semiquantifying 18F-FDG brain uptake in mouse models for AD. Potential reference regions for normalization should be thoroughly investigated to ensure that they are not pathologically affected also by afferent connections.
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Affiliation(s)
- Steven Deleye
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium
| | - Ann-Marie Waldron
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium
| | | | - Mark Schmidt
- Neuroscience Department, Janssen Pharmaceutica NV, Beerse, Belgium
| | - Xavier Langlois
- Neuroscience Department, Janssen Pharmaceutica NV, Beerse, Belgium
| | - Sigrid Stroobants
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium Nuclear Medicine Department, University Hospital Antwerp, Antwerp, Belgium
| | - Steven Staelens
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium
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13
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Faingold CL, Blumenfeld H. Targeting Neuronal Networks with Combined Drug and Stimulation Paradigms Guided by Neuroimaging to Treat Brain Disorders. Neuroscientist 2015; 21:460-74. [PMID: 26150315 PMCID: PMC6287502 DOI: 10.1177/1073858415592377] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Improved therapy of brain disorders can be achieved by focusing on neuronal networks, utilizing combined pharmacological and stimulation paradigms guided by neuroimaging. Neuronal networks that mediate normal brain functions, such as hearing, interact with other networks, which is important but commonly neglected. Network interaction changes often underlie brain disorders, including epilepsy. "Conditional multireceptive" (CMR) brain areas (e.g., brainstem reticular formation and amygdala) are critical in mediating neuroplastic changes that facilitate network interactions. CMR neurons receive multiple inputs but exhibit extensive response variability due to milieu and behavioral state changes and are exquisitely sensitive to agents that increase or inhibit GABA-mediated inhibition. Enhanced CMR neuronal responsiveness leads to expression of emergent properties--nonlinear events--resulting from network self-organization. Determining brain disorder mechanisms requires animals that model behaviors and neuroanatomical substrates of human disorders identified by neuroimaging. However, not all sites activated during network operation are requisite for that operation. Other active sites are ancillary, because their blockade does not alter network function. Requisite network sites exhibit emergent properties that are critical targets for pharmacological and stimulation therapies. Improved treatment of brain disorders should involve combined pharmacological and stimulation therapies, guided by neuroimaging, to correct network malfunctions by targeting specific network neurons.
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Affiliation(s)
- Carl L Faingold
- Departments of Pharmacology and Neurology, Division of Neurosurgery, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Hal Blumenfeld
- Departmens of Neurology, Neurobiology, and Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
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Teng E, Taylor K, Bilousova T, Weiland D, Pham T, Zuo X, Yang F, Chen PP, Glabe CG, Takacs A, Hoffman DR, Frautschy SA, Cole GM. Dietary DHA supplementation in an APP/PS1 transgenic rat model of AD reduces behavioral and Aβ pathology and modulates Aβ oligomerization. Neurobiol Dis 2015; 82:552-560. [PMID: 26369878 DOI: 10.1016/j.nbd.2015.09.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 08/22/2015] [Accepted: 09/07/2015] [Indexed: 12/18/2022] Open
Abstract
Increased dietary consumption of docosahexaenoic acid (DHA) is associated with decreased risk for Alzheimer's disease (AD). These effects have been postulated to arise from DHA's pleiotropic effects on AD pathophysiology, including its effects on β-amyloid (Aβ) production, aggregation, and toxicity. While in vitro studies suggest that DHA may inhibit and reverse the formation of toxic Aβ oligomers, it remains uncertain whether these mechanisms operate in vivo at the physiological concentrations of DHA attainable through dietary supplementation. We sought to clarify the effects of dietary DHA supplementation on Aβ indices in a transgenic APP/PS1 rat model of AD. Animals maintained on a DHA-supplemented diet exhibited reductions in hippocampal Aβ plaque density and modest improvements on behavioral testing relative to those maintained on a DHA-depleted diet. However, DHA supplementation also increased overall soluble Aβ oligomer levels in the hippocampus. Further quantification of specific conformational populations of Aβ oligomers indicated that DHA supplementation increased fibrillar (i.e. putatively less toxic) Aβ oligomers and decreased prefibrillar (i.e. putatively more toxic) Aβ oligomers. These results provide in vivo evidence suggesting that DHA can modulate Aβ aggregation by stabilizing soluble fibrillar Aβ oligomers and thus reduce the formation of both Aβ plaques and prefibrillar Aβ oligomers. However, since fibrillar Aβ oligomers still retain inherent neurotoxicity, DHA may need to be combined with other interventions that can additionally reduce fibrillar Aβ oligomer levels for more effective prevention of AD in clinical settings.
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Affiliation(s)
- Edmond Teng
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA.
| | - Karen Taylor
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Tina Bilousova
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - David Weiland
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Thaidan Pham
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Xiaohong Zuo
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA; Department of Neurobiology and Neurology, Beijing Institute of Geriatrics, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Fusheng Yang
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Ping-Ping Chen
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Charles G Glabe
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, USA; Biochemistry Department and Experimental Biochemistry Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | | | - Dennis R Hoffman
- Retina Foundation of the Southwest, Dallas, TX, USA; Department of Ophthalmology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Sally A Frautschy
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Gregory M Cole
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
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15
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Bilousova T, Taylor K, Emirzian A, Gylys R, Frautschy SA, Cole GM, Teng E. Parallel age-associated changes in brain and plasma neuronal pentraxin receptor levels in a transgenic APP/PS1 rat model of Alzheimer's disease. Neurobiol Dis 2014; 74:32-40. [PMID: 25449907 DOI: 10.1016/j.nbd.2014.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 10/31/2014] [Accepted: 11/04/2014] [Indexed: 11/26/2022] Open
Abstract
Neuronal pentraxin receptor (NPR) is a synaptic protein implicated in AMPA receptor trafficking at excitatory synapses. Since glutamate neurotransmission is disrupted in Alzheimer's disease (AD), NPR levels measured from plasma represent a potential biomarker for synaptic dysfunction associated with AD. We sought to determine the relationship between AD pathology and brain and plasma NPR levels by examining age-associated NPR levels in these compartments in a transgenic APP/PS1 rat model of AD. NPR levels in cortical homogenate were similar in wild-type (Wt) and APP/PS1 rats at 3 months of age (prior to Aβ plaque deposition), but significantly increased in APP/PS1 rats by 9 and 18-20 months of age (after the onset of plaque deposition). These age-dependent differences were driven by proportional increases in NPR in membrane-associated cortical fractions. Genotype-related differences in NPR expression were also seen in the hippocampus, which exhibits significant Aβ pathology, but not in the cerebellum, which does not. Plasma analyses revealed increased levels of a 26 kDa NPR fragment in APP/PS1 rats relative to Wt rats by 18-20 months of age, which correlated with the levels of full-length NPR in cortex. Our findings indicate that cerebral accumulation of NPR and Aβ occurs with similar temporal and regional patterns in the APP/PS1 model, and suggest that a 26 kDa plasma NPR fragment may represent a peripheral biomarker of this process.
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Affiliation(s)
- Tina Bilousova
- Department of Neurology, David Geffen School of Medicine, at UCLA, Los Angeles, CA, United States; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Karen Taylor
- Department of Neurology, David Geffen School of Medicine, at UCLA, Los Angeles, CA, United States; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Ana Emirzian
- Department of Neurology, David Geffen School of Medicine, at UCLA, Los Angeles, CA, United States
| | - Raymond Gylys
- Department of Neurology, David Geffen School of Medicine, at UCLA, Los Angeles, CA, United States
| | - Sally A Frautschy
- Department of Neurology, David Geffen School of Medicine, at UCLA, Los Angeles, CA, United States; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Gregory M Cole
- Department of Neurology, David Geffen School of Medicine, at UCLA, Los Angeles, CA, United States; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Edmond Teng
- Department of Neurology, David Geffen School of Medicine, at UCLA, Los Angeles, CA, United States; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States.
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Adlard PA, Tran BA, Finkelstein DI, Desmond PM, Johnston LA, Bush AI, Egan GF. A review of β-amyloid neuroimaging in Alzheimer's disease. Front Neurosci 2014; 8:327. [PMID: 25400539 PMCID: PMC4215612 DOI: 10.3389/fnins.2014.00327] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 09/27/2014] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia worldwide. As advancing age is the greatest risk factor for developing AD, the number of those afflicted is expected to increase markedly with the aging of the world's population. The inability to definitively diagnose AD until autopsy remains an impediment to establishing effective targeted treatments. Neuroimaging has enabled in vivo visualization of pathological changes in the brain associated with the disease, providing a greater understanding of its pathophysiological development and progression. However, neuroimaging biomarkers do not yet offer clear advantages over current clinical diagnostic criteria for them to be accepted into routine clinical use. Nonetheless, current insights from neuroimaging combined with the elucidation of biochemical and molecular processes in AD are informing the ongoing development of new imaging techniques and their application. Much of this research has been greatly assisted by the availability of transgenic mouse models of AD. In this review we summarize the main efforts of neuroimaging in AD in humans and in mouse models, with a specific focus on β-amyloid, and discuss the potential of new applications and novel approaches.
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Affiliation(s)
- Paul A. Adlard
- Division of Mental Health, The Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, VIC, Australia
| | - Bob A. Tran
- Department of Radiology, University of MelbourneParkville, VIC, Australia
| | - David I. Finkelstein
- Division of Mental Health, The Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, VIC, Australia
| | - Patricia M. Desmond
- Department of Radiology, University of MelbourneParkville, VIC, Australia
- Department of Radiology, The Royal Melbourne HospitalParkville, VIC, Australia
| | - Leigh A. Johnston
- Division of Mental Health, The Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, VIC, Australia
- Department of Electrical and Electronic Engineering, University of MelbourneParkville, VIC, Australia
| | - Ashley I. Bush
- Division of Mental Health, The Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, VIC, Australia
| | - Gary F. Egan
- Monash Biomedical Imaging, Monash UniversityClayton, VIC, Australia
- School of Psychology and Psychiatry, Monash UniversityClayton, VIC, Australia
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Molecular chaperone dysfunction in neurodegenerative diseases and effects of curcumin. BIOMED RESEARCH INTERNATIONAL 2014; 2014:495091. [PMID: 25386560 PMCID: PMC4217372 DOI: 10.1155/2014/495091] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 08/23/2014] [Indexed: 01/26/2023]
Abstract
The intra- and extracellular accumulation of misfolded and aggregated amyloid proteins is a common feature in several neurodegenerative diseases, which is thought to play a major role in disease severity and progression. The principal machineries maintaining proteostasis are the ubiquitin proteasomal and lysosomal autophagy systems, where heat shock proteins play a crucial role. Many protein aggregates are degraded by the lysosomes, depending on aggregate size, peptide sequence, and degree of misfolding, while others are selectively tagged for removal by heat shock proteins and degraded by either the proteasome or phagosomes. These systems are compromised in different neurodegenerative diseases. Therefore, developing novel targets and classes of therapeutic drugs, which can reduce aggregates and maintain proteostasis in the brains of neurodegenerative models, is vital. Natural products that can modulate heat shock proteins/proteosomal pathway are considered promising for treating neurodegenerative diseases. Here we discuss the current knowledge on the role of HSPs in protein misfolding diseases and knowledge gained from animal models of Alzheimer's disease, tauopathies, and Huntington's diseases. Further, we discuss the emerging treatment regimens for these diseases using natural products, like curcumin, which can augment expression or function of heat shock proteins in the cell.
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Zimmer ER, Parent MJ, Cuello AC, Gauthier S, Rosa-Neto P. MicroPET imaging and transgenic models: a blueprint for Alzheimer's disease clinical research. Trends Neurosci 2014; 37:629-41. [PMID: 25151336 DOI: 10.1016/j.tins.2014.07.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 04/30/2014] [Accepted: 07/22/2014] [Indexed: 01/23/2023]
Abstract
Over the past decades, developments in neuroimaging have significantly contributed to the understanding of Alzheimer's disease (AD) pathophysiology. Specifically, positron emission tomography (PET) imaging agents targeting amyloid deposition have provided unprecedented opportunities for refining in vivo diagnosis, monitoring disease propagation, and advancing AD clinical trials. Furthermore, the use of a miniaturized version of PET (microPET) in transgenic (Tg) animals has been a successful strategy for accelerating the development of novel radiopharmaceuticals. However, advanced applications of microPET focusing on the longitudinal propagation of AD pathophysiology or therapeutic strategies remain in their infancy. This review highlights what we have learned from microPET imaging in Tg models displaying amyloid and tau pathology, and anticipates cutting-edge applications with high translational value to clinical research.
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Affiliation(s)
- Eduardo R Zimmer
- Translational Neuroimaging Laboratory (TNL), McGill Center for Studies in Aging, Douglas Mental Health University Institute, Montreal, Quebec, Canada; PET unit, Montreal Neurological Institute (MNI), Montreal, Quebec, Canada; Department of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Maxime J Parent
- Translational Neuroimaging Laboratory (TNL), McGill Center for Studies in Aging, Douglas Mental Health University Institute, Montreal, Quebec, Canada; PET unit, Montreal Neurological Institute (MNI), Montreal, Quebec, Canada
| | - A Claudio Cuello
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada
| | - Serge Gauthier
- Translational Neuroimaging Laboratory (TNL), McGill Center for Studies in Aging, Douglas Mental Health University Institute, Montreal, Quebec, Canada; PET unit, Montreal Neurological Institute (MNI), Montreal, Quebec, Canada
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory (TNL), McGill Center for Studies in Aging, Douglas Mental Health University Institute, Montreal, Quebec, Canada; PET unit, Montreal Neurological Institute (MNI), Montreal, Quebec, Canada.
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Roussotte FF, Daianu M, Jahanshad N, Leonardo CD, Thompson PM. Neuroimaging and genetic risk for Alzheimer's disease and addiction-related degenerative brain disorders. Brain Imaging Behav 2014; 8:217-233. [PMID: 24142306 PMCID: PMC3992278 DOI: 10.1007/s11682-013-9263-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Neuroimaging offers a powerful means to assess the trajectory of brain degeneration in a variety of disorders, including Alzheimer's disease (AD). Here we describe how multi-modal imaging can be used to study the changing brain during the different stages of AD. We integrate findings from a range of studies using magnetic resonance imaging (MRI), positron emission tomography (PET), functional MRI (fMRI) and diffusion weighted imaging (DWI). Neuroimaging reveals how risk genes for degenerative disorders affect the brain, including several recently discovered genetic variants that may disrupt brain connectivity. We review some recent neuroimaging studies of genetic polymorphisms associated with increased risk for late-onset Alzheimer's disease (LOAD). Some genetic variants that increase risk for drug addiction may overlap with those associated with degenerative brain disorders. These common associations offer new insight into mechanisms underlying neurodegeneration and addictive behaviors, and may offer new leads for treating them before severe and irreversible neurological symptoms appear.
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Affiliation(s)
- Florence F Roussotte
- Imaging Genetics Center, Laboratory of Neuro Imaging, Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Madelaine Daianu
- Imaging Genetics Center, Laboratory of Neuro Imaging, Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Neda Jahanshad
- Imaging Genetics Center, Laboratory of Neuro Imaging, Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Cassandra D Leonardo
- Imaging Genetics Center, Laboratory of Neuro Imaging, Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Paul M Thompson
- Imaging Genetics Center, Laboratory of Neuro Imaging, Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
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Bernsen MR, Vaissier PEB, Van Holen R, Booij J, Beekman FJ, de Jong M. The role of preclinical SPECT in oncological and neurological research in combination with either CT or MRI. Eur J Nucl Med Mol Imaging 2014; 41 Suppl 1:S36-49. [PMID: 24895751 PMCID: PMC4003405 DOI: 10.1007/s00259-013-2685-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 12/20/2013] [Indexed: 01/03/2023]
Abstract
Preclinical imaging with SPECT combined with CT or MRI is used more and more frequently and has proven to be very useful in translational research. In this article, an overview of current preclinical research applications and trends of SPECT combined with CT or MRI, mainly in tumour imaging and neuroscience imaging, is given and the advantages and disadvantages of the different approaches are described. Today SPECT and CT systems are often integrated into a single device (commonly called a SPECT/CT system), whereas at present combined SPECT and MRI is almost always carried out with separate systems and fiducial markers to combine the separately acquired images. While preclinical SPECT/CT is most widely applied in oncology research, SPECT combined with MRI (SPECT/MRI when integrated in one system) offers the potential for both neuroscience applications and oncological applications. Today CT and MRI are still mainly used to localize radiotracer binding and to improve SPECT quantification, although both CT and MRI have additional potential. Future technology developments may include fast sequential or simultaneous acquisition of (dynamic) multimodality data, spectroscopy, fMRI along with high-resolution anatomic MRI, advanced CT procedures, and combinations of more than two modalities such as combinations of SPECT, PET, MRI and CT all together. This will all strongly depend on new technologies. With further advances in biology and chemistry for imaging molecular targets and (patho)physiological processes in vivo, the introduction of new imaging procedures and promising new radiopharmaceuticals in clinical practice may be accelerated.
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Affiliation(s)
- Monique R. Bernsen
- Department of Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
- Department of Radiology, Erasmus MC, Rotterdam, The Netherlands
| | - Pieter E. B. Vaissier
- Section Radiation Detection and Medical Imaging, Delft University of Technology, Delft, The Netherlands
| | - Roel Van Holen
- ELIS Department, MEDISIP, Ghent University, iMinds, Ghent, Belgium
| | - Jan Booij
- Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Freek J. Beekman
- Section Radiation Detection and Medical Imaging, Delft University of Technology, Delft, The Netherlands
- MILabs B.V., Utrecht, The Netherlands
| | - Marion de Jong
- Department of Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
- Department of Radiology, Erasmus MC, Rotterdam, The Netherlands
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Do Carmo S, Cuello AC. Modeling Alzheimer's disease in transgenic rats. Mol Neurodegener 2013; 8:37. [PMID: 24161192 PMCID: PMC4231465 DOI: 10.1186/1750-1326-8-37] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 09/28/2013] [Indexed: 11/10/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia. At the diagnostic stage, the AD brain is characterized by the accumulation of extracellular amyloid plaques, intracellular neurofibrillary tangles and neuronal loss. Despite the large variety of therapeutic approaches, this condition remains incurable, since at the time of clinical diagnosis, the brain has already suffered irreversible and extensive damage. In recent years, it has become evident that AD starts decades prior to its clinical presentation. In this regard, transgenic animal models can shed much light on the mechanisms underlying this "pre-clinical" stage, enabling the identification and validation of new therapeutic targets. This paper summarizes the formidable efforts to create models mimicking the various aspects of AD pathology in the rat. Transgenic rat models offer distinctive advantages over mice. Rats are physiologically, genetically and morphologically closer to humans. More importantly, the rat has a well-characterized, rich behavioral display. Consequently, rat models of AD should allow a more sophisticated and accurate assessment of the impact of pathology and novel therapeutics on cognitive outcomes.
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Affiliation(s)
- Sonia Do Carmo
- Department of Pharmacology and Therapeutics, McGill University, 3655 Promenade Sir-William-Osler, Room 1325, Montreal, Quebec H3G 1Y6, Canada
| | - A Claudio Cuello
- Department of Pharmacology and Therapeutics, McGill University, 3655 Promenade Sir-William-Osler, Room 1325, Montreal, Quebec H3G 1Y6, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A 2B2, Canada
- Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec H3A 2B4, Canada
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22
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Sabbagh JJ, Kinney JW, Cummings JL. Alzheimer's disease biomarkers in animal models: closing the translational gap. AMERICAN JOURNAL OF NEURODEGENERATIVE DISEASE 2013; 2:108-120. [PMID: 23844335 PMCID: PMC3703123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 05/31/2013] [Indexed: 06/02/2023]
Abstract
The rising prevalence of Alzheimer's disease (AD) is rapidly becoming one of the largest health and economic challenges in the world. There is a growing need for the development and implementation of reliable biomarkers for AD that can be used to assist in diagnosis, inform disease progression, and monitor therapeutic efficacy. Preclinical models permit the evaluation of candidate biomarkers and assessment of pipeline agents before clinical trials are initiated and provide a translational opportunity to advance biomarker discovery. Fast and inexpensive data can be obtained from examination of peripheral markers, though they currently lack the sensitivity and consistency of imaging techniques such as MRI or PET. Plasma and cerebrospinal fluid (CSF) biomarkers in animal models can assist in development and implementation of similar approaches in clinical populations. These biomarkers may also be invaluable in decisions to advance a treatment to human testing. Longitudinal studies in AD models can determine initial presentation and progression of biomarkers that may also be used to evaluate disease-modifying efficacy of drugs. The refinement of biomarker approaches in preclinical systems will not only aid in drug development, but may facilitate diagnosis and disease monitoring in AD patients.
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Rominger A, Brendel M, Burgold S, Keppler K, Baumann K, Xiong G, Mille E, Gildehaus FJ, Carlsen J, Schlichtiger J, Niedermoser S, Wängler B, Cumming P, Steiner H, Herms J, Haass C, Bartenstein P. Longitudinal assessment of cerebral β-amyloid deposition in mice overexpressing Swedish mutant β-amyloid precursor protein using 18F-florbetaben PET. J Nucl Med 2013; 54:1127-34. [PMID: 23729696 DOI: 10.2967/jnumed.112.114660] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
UNLABELLED The progression of β-amyloid deposition in the brains of mice overexpressing Swedish mutant β-amyloid precursor protein (APP-Swe), a model of Alzheimer disease (AD), was investigated in a longitudinal PET study using the novel β-amyloid tracer (18)F-florbetaben. METHODS Groups of APP-Swe and age-matched wild-type (WT) mice (age range, 10-20 mo) were investigated. Dynamic emission recordings were acquired with a small-animal PET scanner during 90 min after the administration of (18)F-florbetaben (9 MBq, intravenously). After spatial normalization of individual PET recordings to common coordinates for mouse brain, binding potentials (BPND) and standardized uptake value ratios (SUVRs) were calculated relative to the cerebellum. Voxelwise analyses were performed using statistical parametric mapping (SPM). Histochemical analyses and ex vivo autoradiography were ultimately performed in a subset of animals as a gold standard assessment of β-amyloid plaque load. RESULTS SUVRs calculated from static recordings during the interval of 30-60 min after tracer injection correlated highly with estimates of BPND based on the entire dynamic emission recordings. (18)F-florbetaben binding did not significantly differ in APP-Swe mice and WT animals at 10 and 13 mo of age. At 16 mo of age, the APP-Swe mice had a significant 7.9% increase (P < 0.01) in cortical (18)F-florbetaben uptake above baseline and at 20 mo there was a 16.6% increase (P < 0.001), whereas WT mice did not show any temporal changes in tracer uptake during the interval of follow-up. Voxelwise SPM analyses revealed the first signs of increased cortical binding at 13 mo and confirmed progressive binding increases in both the frontal and the temporal cortices (P < 0.001 uncorrected) to 20 mo. The SUVR strongly correlated with percentage plaque load (R = 0.95, P < 0.001). CONCLUSION In the first longitudinal PET study in an AD mouse model using the novel β-amyloid tracer (18)F-florbetaben, the temporal and spatial progression of amyloidogenesis in the brain of APP-Swe mice were sensitively monitored. This method should afford the means for preclinical testing of novel therapeutic approaches to the treatment of AD.
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Affiliation(s)
- Axel Rominger
- Department of Nuclear Medicine, Ludwig-Maximilians-University of Munich, Munich, Germany.
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Alzheimer's disease biomarkers: correspondence between human studies and animal models. Neurobiol Dis 2013; 56:116-30. [PMID: 23631871 DOI: 10.1016/j.nbd.2013.04.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 04/11/2013] [Accepted: 04/18/2013] [Indexed: 01/05/2023] Open
Abstract
Alzheimer's disease (AD) represents an escalating global threat as life expectancy and disease prevalence continue to increase. There is a considerable need for earlier diagnoses to improve clinical outcomes. Fluid biomarkers measured from cerebrospinal fluid (CSF) and blood, or imaging biomarkers have considerable potential to assist in the diagnosis and management of AD. An additional important utility of biomarkers is in novel therapeutic development and clinical trials to assess efficacy and side effects of therapeutic interventions. Because many biomarkers are initially examined in animal models, the extent to which markers translate from animals to humans is an important issue. The current review highlights many existing and pipeline biomarker approaches, focusing on the degree of correspondence between AD patients and animal models. The review also highlights the need for greater translational correspondence between human and animal biomarkers.
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25
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Rojas S, Herance JR, Gispert JD, Abad S, Torrent E, Jiménez X, Pareto D, Perpiña U, Sarroca S, Rodríguez E, Ortega-Aznar A, Sanfeliu C. In vivo evaluation of amyloid deposition and brain glucose metabolism of 5XFAD mice using positron emission tomography. Neurobiol Aging 2013; 34:1790-8. [PMID: 23402900 DOI: 10.1016/j.neurobiolaging.2012.12.027] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 12/03/2012] [Accepted: 12/27/2012] [Indexed: 10/27/2022]
Abstract
Positron emission tomography (PET) has been used extensively to evaluate the neuropathology of Alzheimer's disease (AD) in vivo. Radiotracers directed toward the amyloid deposition such as [(18)F]-FDDNP (2-(1-{6-[(2-[F]Fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile) and [(11)C]-PIB (Pittsburg compound B) have shown exceptional value in animal models and AD patients. Previously, the glucose analogue [(18)F]-FDG (2-[(18)F]fluorodeoxyglucose) allowed researchers and clinicians to evaluate the brain glucose consumption and proved its utility for the early diagnosis and the monitoring of the progression of AD. Animal models of AD are based on the transgenic expression of different human mutant genes linked to familial AD. The novel transgenic 5XFAD mouse containing 5 mutated genes in its genome has been proposed as an AD model with rapid and massive cerebral amyloid deposition. PET studies performed with animal-dedicated scanners indicate that PET with amyloid-targeted radiotracers can detect the pathological amyloid deposition in transgenic mice and rats. However, in other studies no differences were found between transgenic mice and their wild type littermates. We sought to investigate in 5XFAD mice if the radiotracers [(11)C]-PIB, and [(18)F]-Florbetapir could quantify the amyloid deposition in vivo and if [(18)F]-FDG could do so with regard to glucose consumption. We found that 5XFAD animals presented higher cerebral binding of [(18)F]-Florbetapir, [(11)C]-PIB, and [(18)F]-FDG. These results support the use of amyloid PET radiotracers for the evaluation of AD animal models. Probably, the increased uptake observed with [(18)F]-FDG is a consequence of glial activation that occurs in 5XFAD mice.
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Affiliation(s)
- Santiago Rojas
- CRC Centre d'Imatge Molecular, CRC Corporació Sanitària, Barcelona, Spain.
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Smid LM, Kepe V, Vinters HV, Bresjanac M, Toyokuni T, Satyamurthy N, Wong KP, Huang SC, Silverman DH, Miller K, Small GW, Barrio JR. Postmortem 3-D brain hemisphere cortical tau and amyloid-β pathology mapping and quantification as a validation method of neuropathology imaging. J Alzheimers Dis 2013; 36:261-74. [PMID: 23568102 PMCID: PMC3688653 DOI: 10.3233/jad-122434] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
This work is aimed at correlating pre-mortem [18F]FDDNP positron emission tomography (PET) scan results in a patient with dementia with Lewy bodies (DLB), with cortical neuropathology distribution determined postmortem in three physical dimensions in whole brain coronal sections. Analysis of total amyloid-β (Aβ) distribution in frontal cortex and posterior cingulate gyrus confirmed its statistically significant correlation with cortical [18F]FDDNP PET binding values (distribution volume ratios, DVR) (p < 0.001, R = 0.97, R2 = 0.94). Neurofibrillary tangle (NFT) distribution correlated significantly with cortical [18F]FDDNP PET DVR in the temporal lobe (p < 0.001, R = 0.87, R2 = 0.76). Linear combination of Aβ and NFT densities was highly predictive of [18F]FDDNP PET DVR through all analyzed regions of interest (p < 0.0001, R = 0.92, R2 = 0.85), and both densities contributed significantly to the model. Lewy bodies were present at a much lower level than either Aβ or NFTs and did not significantly contribute to the in vivo signal. [18F]FDG PET scan results in this patient were consistent with the distinctive DLB pattern of hypometabolism. This work offers a mapping brain model applicable to all imaging probes for verification of imaging results with Aβ and/or tau neuropathology brain distribution using immunohistochemistry, fluorescence microscopy, and autoradiography.
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Affiliation(s)
- Lojze M. Smid
- David Geffen School of Medicine at UCLA, Los Angeles, CA
- School of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Vladimir Kepe
- David Geffen School of Medicine at UCLA, Los Angeles, CA
| | | | - Mara Bresjanac
- School of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | | | - N. Satyamurthy
- David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Koon-Pong Wong
- David Geffen School of Medicine at UCLA, Los Angeles, CA
| | | | | | - Karen Miller
- David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Gary W. Small
- David Geffen School of Medicine at UCLA, Los Angeles, CA
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Virdee K, Cumming P, Caprioli D, Jupp B, Rominger A, Aigbirhio FI, Fryer TD, Riss PJ, Dalley JW. Applications of positron emission tomography in animal models of neurological and neuropsychiatric disorders. Neurosci Biobehav Rev 2012; 36:1188-216. [PMID: 22342372 DOI: 10.1016/j.neubiorev.2012.01.009] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 01/26/2012] [Accepted: 01/31/2012] [Indexed: 01/08/2023]
Abstract
Positron emission tomography (PET) provides dynamic images of the biodistribution of radioactive tracers in the brain. Through application of the principles of compartmental analysis, tracer uptake can be quantified in terms of specific physiological processes such as cerebral blood flow, cerebral metabolic rate, and the availability of receptors in brain. Whereas early PET studies in animal models of brain diseases were hampered by the limited spatial resolution of PET instruments, dedicated small-animal instruments now provide molecular images of rodent brain with resolution approaching 1mm, the theoretic limit of the method. Major applications of PET for brain research have consisted of studies of animal models of neurological disorders, notably Parkinson's disease (PD), Alzheimer's disease (AD), and Huntington's disease (HD), stroke, epilepsy and traumatic brain injury; these studies have particularly benefited from selective neurochemical lesion models (PD), and also transgenic rodent models (AD, HD). Due to their complex and uncertain pathophysiologies, corresponding models of neuropsychiatric disorders have proven more difficult to establish. Historically, there has been an emphasis on PET studies of dopamine transmission, as assessed with a range of tracers targeting dopamine synthesis, plasma membrane transporters, and receptor binding sites. However, notable recent breakthroughs in molecular imaging include the development of greatly improved tracers for subtypes of serotonin, cannabinoid, and metabotropic glutamate receptors, as well as noradrenaline transporters, amyloid-β and neuroinflammatory changes. This article reviews the considerable recent progress in preclinical PET and discusses applications relevant to a number of neurological and neuropsychiatric disorders in humans.
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Affiliation(s)
- Kanwar Virdee
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, CB2 3EB, UK
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Wong KP, Kepe V, Dahlbom M, Satyamurthy N, Small GW, Barrio JR, Huang SC. Comparative evaluation of Logan and relative-equilibrium graphical methods for parametric imaging of dynamic [18F]FDDNP PET determinations. Neuroimage 2011; 60:241-51. [PMID: 22197787 DOI: 10.1016/j.neuroimage.2011.12.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Revised: 12/04/2011] [Accepted: 12/06/2011] [Indexed: 02/08/2023] Open
Abstract
UNLABELLED Logan graphical analysis with cerebellum as reference region has been widely used for the estimation of the distribution volume ratio (DVR) of [(18)F]FDDNP as a measure of amyloid burden and tau deposition in human brain because of its simplicity and computational ease. However, spurious parametric DVR images may be produced with shorter scanning times and when the noise level is high. In this work, we have characterized a relative-equilibrium-based (RE) graphical method against the Logan analysis for parametric imaging and region-of-interest (ROI) analysis. METHODS Dynamic [(18)F]FDDNP PET scans were performed on 9 control subjects and 12 patients diagnosed with Alzheimer's disease. Using the cerebellum as reference input, regional DVR estimates were derived using both the Logan analysis and the RE plot approach. Effects on DVR estimates obtained at voxel and ROI levels by both graphical approaches using data in different time windows were investigated and compared with the standard values derived using the Logan analysis on a voxel-by-voxel basis for the time window of 35-125 min used in previous studies. RESULTS Larger bias and variability were observed for DVR estimates obtained by the Logan graphical analysis at the voxel level when short time windows (85-125 and 45-65 min) were used, because of high noise levels in voxel-wise parametric imaging. However, when the Logan graphical analysis was applied at the ROI level over those short time windows, the DVR estimates did not differ significantly from the standard values derived using the Logan analysis on the voxel level for the time window of 35-125 min, and their bias and variability were remarkably lower. Conversely, the RE plot approach was more robust in providing DVR estimates with less bias and variability even when short time windows were used. The DVR estimates obtained at voxel and ROI levels were consistent. No significant differences were observed in DVR estimates obtained by the RE plot approach for all paired comparisons with the standard values. CONCLUSIONS The RE plot approach provides less noisy parametric images and gives consistent and reliable regional DVR estimates at both voxel and ROI levels, indicating that it is preferred over the Logan graphical analysis for analyzing [(18)F]FDDNP PET data.
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Affiliation(s)
- Koon-Pong Wong
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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