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D'Elia A, Schiavi S, Soluri A, Massari R, Soluri A, Trezza V. Role of Nuclear Imaging to Understand the Neural Substrates of Brain Disorders in Laboratory Animals: Current Status and Future Prospects. Front Behav Neurosci 2020; 14:596509. [PMID: 33362486 PMCID: PMC7759612 DOI: 10.3389/fnbeh.2020.596509] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 11/23/2020] [Indexed: 12/18/2022] Open
Abstract
Molecular imaging, which allows the real-time visualization, characterization and measurement of biological processes, is becoming increasingly used in neuroscience research. Scintigraphy techniques such as single photon emission computed tomography (SPECT) and positron emission tomography (PET) provide qualitative and quantitative measurement of brain activity in both physiological and pathological states. Laboratory animals, and rodents in particular, are essential in neuroscience research, providing plenty of models of brain disorders. The development of innovative high-resolution small animal imaging systems together with their radiotracers pave the way to the study of brain functioning and neurotransmitter release during behavioral tasks in rodents. The assessment of local changes in the release of neurotransmitters associated with the performance of a given behavioral task is a turning point for the development of new potential drugs for psychiatric and neurological disorders. This review addresses the role of SPECT and PET small animal imaging systems for a better understanding of brain functioning in health and disease states. Brain imaging in rodent models faces a series of challenges since it acts within the boundaries of current imaging in terms of sensitivity and spatial resolution. Several topics are discussed, including technical considerations regarding the strengths and weaknesses of both technologies. Moreover, the application of some of the radioligands developed for small animal nuclear imaging studies is discussed. Then, we examine the changes in metabolic and neurotransmitter activity in various brain areas during task-induced neural activation with special regard to the imaging of opioid, dopaminergic and cannabinoid receptors. Finally, we discuss the current status providing future perspectives on the most innovative imaging techniques in small laboratory animals. The challenges and solutions discussed here might be useful to better understand brain functioning allowing the translation of preclinical results into clinical applications.
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Affiliation(s)
- Annunziata D'Elia
- Institute of Biochemistry and Cell Biology, National Research Council of Italy (CNR), Rome, Italy.,Section of Biomedical Sciences and Technologies, Department of Science, University "Roma Tre", Rome, Italy
| | - Sara Schiavi
- Section of Biomedical Sciences and Technologies, Department of Science, University "Roma Tre", Rome, Italy
| | - Andrea Soluri
- Institute of Biochemistry and Cell Biology, National Research Council of Italy (CNR), Rome, Italy
| | - Roberto Massari
- Institute of Biochemistry and Cell Biology, National Research Council of Italy (CNR), Rome, Italy
| | - Alessandro Soluri
- Institute of Biochemistry and Cell Biology, National Research Council of Italy (CNR), Rome, Italy
| | - Viviana Trezza
- Section of Biomedical Sciences and Technologies, Department of Science, University "Roma Tre", Rome, Italy
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Bascuñana P, García-García L, Javela J, Fernández de la Rosa R, Shiha AA, Kelly J, Delgado M, Pozo MÁ. PET Neuroimaging Reveals Serotonergic and Metabolic Dysfunctions in the Hippocampal Electrical Kindling Model of Epileptogenesis. Neuroscience 2019; 409:101-110. [PMID: 31034972 DOI: 10.1016/j.neuroscience.2019.04.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/10/2019] [Accepted: 04/12/2019] [Indexed: 12/29/2022]
Abstract
Glucose metabolism and serotonergic neurotransmission have been reported to play an important role in epileptogenesis. We therefore aimed to use neuroimaging to evaluate potential alterations in serotonin 5-HT1A receptor and glucose metabolism during epileptogenesis in the rat electrical kindling model. To achieve this goal, we performed positron emission tomography (PET) imaging in a rat epileptogenesis model triggered by electrical stimulation of the hippocampus using 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG), a radiolabeled analog of glucose, and 2'-methoxyphenyl-(N-2'-pyridinyl)-p-18F-fluoro-benzamidoethylpiperazine (18F-MPPF), a radiolabeled 5-HT1A receptor ligand, to evaluate brain metabolism and 5-HT1A receptor functionality. Since the 5-HT1A receptor is also highly expressed in astrocytes, glial fibrillary acidic protein (GFAP) immunofluorescence was performed to detect astrogliosis arising from the kindling procedure once the study was finalized. Lastly, in vitro18F-MPPF autoradiography was performed to evaluate changes in 5HT1A receptor expression. 18F-FDG PET showed reduction of glucose uptake in cortical structures, whereas 18F-MPPF PET revealed an enhancement of tracer binding potential (BPND) in key areas rich in 5-HT1A receptor involved in epilepsy, including septum, hippocampus and entorhinal cortex of kindled animals compared to controls. However, in vitro 5-HT1A receptor autoradiography showed no changes in densitometric signal in any brain region, suggesting that the augmentation in BPND found by PET could be caused by reduction of synaptic serotonin. Importantly, astroglial activation was detected in the hippocampus of kindled rats. Overall, electrical kindling induced hypometabolism, astrogliosis and serotonergic alterations in epilepsy-related regions. Furthermore, the present findings point to 5-HT1A receptor as a valuable epileptogenesis biomarker candidate and a potential therapeutic target.
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Affiliation(s)
- Pablo Bascuñana
- Unidad de Cartografía Cerebral, Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII, 1, 28040, Madrid, Spain.
| | - Luis García-García
- Unidad de Cartografía Cerebral, Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII, 1, 28040, Madrid, Spain; Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040, Madrid, Spain
| | - Julián Javela
- Grupo de Clínica y Salud Mental, Programa de Psicología, Universidad Católica de Pereira, Av Sur/Las Américas, Pereira, Colombia
| | - Rubén Fernández de la Rosa
- Unidad de Cartografía Cerebral, Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII, 1, 28040, Madrid, Spain
| | - Ahmed Anis Shiha
- Unidad de Cartografía Cerebral, Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII, 1, 28040, Madrid, Spain
| | - James Kelly
- Department of Radiology, Weill Cornell Medicine, New York, NY 10021, USA; Curium Pharma Spain (formerly Instituto Tecnológico PET), C/ Manuel Bartolomé Cossío, 10, 28040, Madrid, Spain
| | - Mercedes Delgado
- Unidad de Cartografía Cerebral, Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII, 1, 28040, Madrid, Spain; Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040, Madrid, Spain
| | - Miguel Ángel Pozo
- Unidad de Cartografía Cerebral, Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII, 1, 28040, Madrid, Spain; Curium Pharma Spain (formerly Instituto Tecnológico PET), C/ Manuel Bartolomé Cossío, 10, 28040, Madrid, Spain; Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040, Madrid, Spain
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3
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Tsartsalis S, Tournier BB, Habiby S, Ben Hamadi M, Barca C, Ginovart N, Millet P. Dual-radiotracer translational SPECT neuroimaging. Comparison of three methods for the simultaneous brain imaging of D2/3 and 5-HT2A receptors. Neuroimage 2018; 176:528-540. [DOI: 10.1016/j.neuroimage.2018.04.063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 03/11/2018] [Accepted: 04/27/2018] [Indexed: 12/27/2022] Open
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Herde A, Ioanas HI, Boss S, Seifritz E, Ametamey S, Saab B. Using Tandem Behaviour-PET to Examine Dopaminergic Signalling Underlying Exploration. ACTA ACUST UNITED AC 2017. [DOI: 10.19185/matters.201702000008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
During the past years, non-neuronal vascular nicotinic acetylcholine receptors (nAChRs) increasingly have gained interest in cardiovascular research, as they are known to mediate the deleterious effects of nicotine and nitrosamines, components of tobacco smoke, on the vasculature. Because smoking is a major risk factor for the development of atherosclerosis, it is obvious that understanding the pathophysiologic role of nAChRs in the atherosclerotic disease process, as well as in the development of new diagnostic and therapeutic nAChR-related options, has become more important. Accordingly, we briefly summarize the pathophysiologic role of vascular nAChRs in the atherosclerotic disease process. We also provide an overview of currently available nAChR positron emission tomography (PET) tracers and their performance in the noninvasive imaging of vascular nAChRs, as well as potential nAChR PET tracers that might be an option for vascular nAChR PET imaging in the future.
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Affiliation(s)
- Matthias Bauwens
- Department of Nuclear Medicine, Maastricht University Medical Center (MUMC+), Maastricht, The Netherlands
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Sharma AK, Morrison JP, Rao DB, Pardo ID, Garman RH, Bolon B. Toxicologic Pathology Analysis for Translational Neuroscience. Int J Toxicol 2016; 35:410-9. [DOI: 10.1177/1091581816636372] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A half-day American College of Toxicology continuing education course presented key issues often confronted by translational neuroscientists when predicting human risk from animal-derived toxicologic pathology data. Two talks correlated discrete structures with major functions in brains of rodents and nonrodents. The third lecture provided practical advice to obtain highly homologous rodent brain sections for quantitative morphometry in developmental neurotoxicity testing. The last presentation discussed demographic influences (eg, species, strain, sex, age), physiological attributes (eg, body composition, brain vascularity, pharmacokinetic/pharmacodynamic patterns, etc), and husbandry parameters (eg, group housing) recognized to impact the actions of neuroactive chemicals. Speakers described common cases of real-world challenges to animal data interpretation encountered when designing studies or extrapolating biological responses across species. The efficiency of translational neuroscience efforts will likely be enhanced as new methods (eg, high-resolution non-invasive imaging) improve our capability to cross-connect subtle anatomic and/or biochemical lesions with functional changes over time.
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Affiliation(s)
| | | | - Deepa B. Rao
- Center for Drug Evaluation and Research (CDER), US Food and Drug Administration, Silver Spring, MD, USA
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7
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In vivo imaging of CREB phosphorylation in awake-mouse brain. Sci Rep 2015; 5:9757. [PMID: 26044058 PMCID: PMC4456726 DOI: 10.1038/srep09757] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 03/17/2015] [Indexed: 12/28/2022] Open
Abstract
The cyclic adenosine monophosphate response element binding protein (CREB) is a phosphorylation-dependent transcription factor that plays important roles in memory consolidation and several neuropsychological disorders. Although analyzing the spatiotemporal pattern of CREB phosphorylation is required for elucidating the mechanism of memory consolidation, imaging of phosphorylation of a particular protein in the brain of live animals is impossible at present. Here, we developed a method for visualizing the CREB phosphorylation in the cerebral cortex of an awake mouse using a split luciferase technique. Using this technique, we demonstrated the correlation between the change in CREB phosphorylation at a particular region in the brain and behavioral consequences induced by the administration of reserpine, a psychotropic agent.
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Chiu CH, Li IH, Weng SJ, Huang YS, Wu SC, Chou TK, Huang WS, Liao MH, Shiue CY, Cheng CY, Ma KH. PET Imaging of Serotonin Transporters With 4-[(18)F]-ADAM in a Parkinsonian Rat Model With Porcine Neural Xenografts. Cell Transplant 2015; 25:301-11. [PMID: 25994923 DOI: 10.3727/096368915x688236] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disease characterized by a loss of dopaminergic neurons in the nigrostriatal pathway. Apart from effective strategies to halt the underlying neuronal degeneration, cell replacement now offers novel prospects for PD therapy. Porcine embryonic neural tissue has been considered an alternative source to human fetal grafts in neurodegenerative disorders because its use avoids major practical and ethical issues. This study was undertaken to evaluate the effects of embryonic day 27 (E27) porcine mesencephalic tissue transplantation in a PD rat model using animal positron emission tomography (PET) coupled with 4-[(18)F]-ADAM, a serotonin transporter (SERT) imaging agent. The parkinsonian rat was induced by injecting 6-hydroxydopamine into the medial forebrain bundle (MFB) of the right nigrostriatal pathway. The apomorphine-induced rotation behavioral test and 4-[(18)F]-ADAM/animal PET scanning were carried out following 6-OHDA lesioning. At the second week following 6-OHDA lesioning, the parkinsonian rat rotates substantially on apomorphine-induced contralateral turning. In addition, the mean striatal-specific uptake ratio (SUR) of 4-[(18)F]-ADAM decreased by 44%. After transplantation, the number of drug-induced rotations decreased markedly, and the mean SUR of 4-[(18)F]-ADAM and the level of SERT immunoreactivity (SERT-ir) in striatum were partially restored. The mean SUR level was restored to 71% compared to that for the contralateral intact side, which together with the abundant survival of tyrosine hydroxylase (TH) neurons accounted for functional recovery at the fourth week postgraft. In regard to the extent of donor-derived cells, we found the neurons of the xenografts from E27 transgenic pigs harboring red fluorescent protein (RFP) localized with TH-ir cells and SERT-ir in the grafted area. Thus, transplanted E27 porcine mesencephalic tissue may restore dopaminergic and serotonergic systems in the parkinsonian rat. The 4-[(18)F]-ADAM/animal PET can be used to detect serotonergic neuron loss in PD and monitor the efficacy of therapy.
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Affiliation(s)
- Chuang-Hsin Chiu
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
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Cerebral glucose metabolism changes in rat brain upon forepaw electrical stimulation at different frequencies. Neuroreport 2015; 26:197-205. [PMID: 25674904 DOI: 10.1097/wnr.0000000000000327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PET imaging techniques and statistical parametric mapping analysis have been developed to identify neuronal functional activation from brain imaging. The purpose of this study was to examine the efficacy of the glucose metabolism in rat brain during forepaw electrical stimulation with different frequencies (3, 10, or 20 Hz) compared with a nonstimulated group (control). Fluorine-18 fluorodeoxyglucose was injected after confirmation of the range of normal physiology. For quantitative analysis, we used cerebral metabolism rate of glucose consumption (CMRglc) responses in the primary somatosensory cortex (S1FL) and motor cortex (M1). On comparing CMRglc responses in the contralateral S1FL and M1 with those of the ipsilateral areas in intragroup analysis, a significant increase (P<0.05) was observed in two electrical stimulation groups (10 and 20 Hz) but not at the 3 Hz level. In intergroup analysis, the CMRglc responses in the contralateral region of interest were compared with those of the control group to validate which electrical frequency conditions were appropriate to induce neuronal functional activation. Among the stimulation groups, significant increases in CMRglc response were only observed at 10 Hz (P<0.05). Therefore, 10 Hz is the most suitable frequency to confirm changes in CMRglc in the S1FL and M1 of the rat brain, and also fluorine-18 fluorodeoxyglucose PET could be useful to investigate recovery and plasticity in neurological diseases associated with primary sensory-motor cortex function.
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10
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Morrison JP, Sharma AK, Rao D, Pardo ID, Garman RH, Kaufmann W, Bolon B. Fundamentals of translational neuroscience in toxicologic pathology: optimizing the value of animal data for human risk assessment. Toxicol Pathol 2014; 43:132-9. [PMID: 25398755 DOI: 10.1177/0192623314558306] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A half-day Society of Toxicologic Pathology continuing education course on "Fundamentals of Translational Neuroscience in Toxicologic Pathology" presented some current major issues faced when extrapolating animal data regarding potential neurological consequences to assess potential human outcomes. Two talks reviewed functional-structural correlates in rodent and nonrodent mammalian brains needed to predict behavioral consequences of morphologic changes in discrete neural cell populations. The third lecture described practical steps for ensuring that specimens from rodent developmental neurotoxicity tests will be processed correctly to produce highly homologous sections. The fourth talk detailed demographic factors (e.g., species, strain, sex, and age); physiological traits (body composition, brain circulation, pharmacokinetic/pharmacodynamic patterns, etc.); and husbandry influences (e.g., group housing) known to alter the effects of neuroactive agents. The last presentation discussed the appearance, unknown functional effects, and potential relevance to humans of polyethylene glycol (PEG)-associated vacuoles within the choroid plexus epithelium of animals. Speakers provided real-world examples of challenges with data extrapolation among species or with study design considerations that may impact the interpretability of results. Translational neuroscience will be bolstered in the future as less invasive and/or more quantitative techniques are devised for linking overt functional deficits to subtle anatomic and chemical lesions.
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Affiliation(s)
| | | | - Deepa Rao
- National Toxicology Program, National Institute of Environmental Health Sciences and Integrated Laboratory Systems, Research Triangle Park, North Carolina, USA
| | | | - Robert H Garman
- Consultants in Veterinary Pathology, Inc., Murrysville, Pennsylvania, USA
| | | | - Brad Bolon
- The Ohio State University, College of Veterinary Medicine, Columbus, Ohio, USA
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11
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Development of (18)F-labeled radiotracers for neuroreceptor imaging with positron emission tomography. Neurosci Bull 2014; 30:777-811. [PMID: 25172118 DOI: 10.1007/s12264-014-1460-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Accepted: 06/02/2014] [Indexed: 12/14/2022] Open
Abstract
Positron emission tomography (PET) is an in vivo molecular imaging tool which is widely used in nuclear medicine for early diagnosis and treatment follow-up of many brain diseases. PET uses biomolecules as probes which are labeled with radionuclides of short half-lives, synthesized prior to the imaging studies. These probes are called radiotracers. Fluorine-18 is a radionuclide routinely used in the radiolabeling of neuroreceptor ligands for PET because of its favorable half-life of 109.8 min. The delivery of such radiotracers into the brain provides images of transport, metabolic, and neurotransmission processes on the molecular level. After a short introduction into the principles of PET, this review mainly focuses on the strategy of radiotracer development bridging from basic science to biomedical application. Successful radiotracer design as described here provides molecular probes which not only are useful for imaging of human brain diseases, but also allow molecular neuroreceptor imaging studies in various small-animal models of disease, including genetically-engineered animals. Furthermore, they provide a powerful tool for in vivo pharmacology during the process of pre-clinical drug development to identify new drug targets, to investigate pathophysiology, to discover potential drug candidates, and to evaluate the pharmacokinetics and pharmacodynamics of drugs in vivo.
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12
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Welch A, Mingarelli M, Riedel G, Platt B. Mapping changes in mouse brain metabolism with PET/CT. J Nucl Med 2013; 54:1946-53. [PMID: 24009277 DOI: 10.2967/jnumed.113.121509] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Because preclinical imaging offers challenges and opportunities, we set out to investigate and optimize image processing techniques to measure changes in mouse brain metabolism with preclinical (18)F-FDG PET/CT. In particular, we considered the effects of scan length, image registration methods, image quantification methods, and smoothing during statistical parametric mapping (SPM). METHODS A cohort of 12 wild-type mice was scanned on 3 occasions at an average age of 6, 10, and 14 mo. The impact of the scan length (10, 20, 30, or 40 min) was determined, and images were registered to a template based on either the PET or the CT image. Analysis was performed using SPM or predefined regions of interest (ROIs). Data were expressed in units of standardized uptake value or percentage injected dose per gram of tissue for absolute values; images were also normalized to whole-brain activity. RESULTS Significant variability was observed in global brain (18)F-FDG uptake between animals. Normalizing images to the whole-brain activity significantly improved detection of regional changes in metabolism. Registration based on CT images provided greater power for detecting changes in metabolism than did registration based on PET images only. In line with an age-dependent decline in brain metabolism, both ROI and SPM-based methods revealed significant changes; SPM, however, was generally more sensitive and region-specific. For example, small clusters of voxels within an ROI differed significantly between ages even in the absence of significant changes in average uptake over the whole region. Finally, and contrary to expectation, we found little benefit from longer scan times yet a marked reduction in uptake from 45 to 85 min after injection and regional variations in the rate of washout. CONCLUSION With appropriate processing, preclinical PET/CT provides a highly sensitive method for reliable identification of metabolic changes in the mouse brain.
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Affiliation(s)
- Andy Welch
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, United Kingdom; and
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13
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Kim HS, An YS, Paik MJ, Lee YS, Choi HD, Kim BC, Pack JK, Kim N, Ahn YH. The effects of exposure to 915 MHz radiofrequency identification on cerebral glucose metabolism in rat: a [F-18] FDG micro-PET study. Int J Radiat Biol 2013; 89:750-5. [PMID: 23581879 DOI: 10.3109/09553002.2013.791756] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE We investigated the effect of whole-body exposure to 915-MHz radiofrequency identification (RFID) on rat cortical glucose metabolism by using (18)F-deoxyglucose positron emission tomography (FDG-PET). MATERIALS AND METHODS Male Sprague-Dawley rats were divided into three groups: Cage-control, sham-exposed and RFID-exposed groups. Rats were exposed to the 915-MHz RFID for 8 h daily, 5 days per week, for 2 or 16 weeks. The whole-body average specific absorption rate (SAR) was 4 W/kg for the field of the 915 MHz RFID signal. FDG-PET images were obtained the day after RFID exposure, using micro-PET with a FDG tracer. With a Xeleris functional imaging workstation, absolute values in regions of interest (ROI) in the frontal, temporal and parietal cortexes and cerebellum were measured. Cortical ROI values were normalized to the cerebellar value and compared. RESULTS The data showed that the relative cerebral glucose metabolic rate was unchanged in the frontal, temporal and parietal cortexes of the 915 MHz RFID-exposed rats, compared with rats in cage-control and sham-exposed groups. CONCLUSION Our results suggest that 915 MHz RFID radiation exposure did not cause a significant long lasting effect on glucose metabolism in the rat brain.
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Affiliation(s)
- Hye Sun Kim
- Department of Neurosurgery, Ajou University School of Medicine, Suwon, South Korea
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Khanbabaie R, Jahanshahi M. Revolutionary impact of nanodrug delivery on neuroscience. Curr Neuropharmacol 2012; 10:370-92. [PMID: 23730260 PMCID: PMC3520046 DOI: 10.2174/157015912804143513] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 08/09/2012] [Accepted: 08/28/2012] [Indexed: 12/23/2022] Open
Abstract
Brain research is the most expanding interdisciplinary research that is using the state of the art techniques to overcome limitations in order to conduct more accurate and effective experiments. Drug delivery to the target site in the central nervous system (CNS) is one of the most difficult steps in neuroscience researches and therapies. Taking advantage of the nanoscale structure of neural cells (both neurons and glia); nanodrug delivery (second generation of biotechnological products) has a potential revolutionary impact into the basic understanding, visualization and therapeutic applications of neuroscience. Current review article firstly provides an overview of preparation and characterization, purification and separation, loading and delivering of nanodrugs. Different types of nanoparticle bioproducts and a number of methods for their fabrication and delivery systems including (carbon) nanotubes are explained. In the second part, neuroscience and nervous system drugs are deeply investigated. Different mechanisms in which nanoparticles enhance the uptake and clearance of molecules form cerebrospinal fluid (CSF) are discussed. The focus is on nanodrugs that are being used or have potential to improve neural researches, diagnosis and therapy of neurodegenerative disorders.
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Affiliation(s)
- Reza Khanbabaie
- Nanotechnology Research Institute, Babol University of Technology, Babol, Iran
- Faculty of Basic Science, Department of Physics, Babol University of Technology, Babol, Iran
- Department of Physics, University of Ottawa, Ottawa, Canada
| | - Mohsen Jahanshahi
- Nanotechnology Research Institute, Babol University of Technology, Babol, Iran
- Faculty of Chemical Engineering, Babol University of Technology, Babol, Iran
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15
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Millet P, Moulin-Sallanon M, Tournier BB, Dumas N, Charnay Y, Ibáñez V, Ginovart N. Quantification of dopamine D(2/3) receptors in rat brain using factor analysis corrected [18F]Fallypride images. Neuroimage 2012; 62:1455-68. [PMID: 22659483 DOI: 10.1016/j.neuroimage.2012.05.075] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 04/20/2012] [Accepted: 05/26/2012] [Indexed: 11/15/2022] Open
Abstract
The goal of this work is to quantify the binding parameters of [(18)F]Fallypride in the striatal and extrastriatal regions of the rat brain using factor analysis (FA) to correct small animal PET kinetic imaging for spillover defluorination radioactivity. Eleven rats were employed for YAP-(S)PET acquisitions and metabolite studies. All kinetic parameters including B'(max) and K(d)V(R) were estimated with a three-tissue compartment seven-parameter model (3T-7k) on the basis of all the FA-corrected data from the multi-injection protocol. Binding potential (BP(ND)) was calculated with Logan's graphical analysis taking cerebellum as the reference region and using the first injection raw (BP(ND-RAW)) and FA-corrected (BP(ND-FA)) data. Three distinct factors corresponding to free+non-specific binding, specific binding and skull and gland accumulation were recovered from FA with their corresponding spatial distributions. The resulting reconstructed images without skull and gland accumulation were improved to provide a better contrast between specific and non-specific regions. Very bad fits were obtained when using time-activity curves (TACs) calculated from the raw [(18)F]Fallypride data, whereas all TACs were well fitted by the 3T-7k model after FA correction. FA-corrected data enables the cerebellar region to be used as reference for the Logan approach. The magnitude of the BP(ND-FA) values was increased from 21% to 108% across regions and the rank order of BP(ND-FA) values (Cx<Hip<MB≈Thal<VST<DST) matched those of B'(max) values. This [(18)F]Fallypride study in rats shows that all brain regions are contaminated by skull and gland radioactivity accumulation. We show that FA is a very effective method of correcting kinetic data for spillover activity. Moreover, the approach presented here with [(18)F]Fallypride data can be extended to other radioligands and also to human data which can be highly distorted by radiodefluorination as shown in the literature.
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Affiliation(s)
- Philippe Millet
- Clinical Neurophysiology and Neuroimaging Unit, Division of Neuropsychiatry, Department of Psychiatry, University Hospitals of Geneva, Switzerland.
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Hoehn M, Aswendt M. Structure-function relationship of cerebral networks in experimental neuroscience: contribution of magnetic resonance imaging. Exp Neurol 2012; 242:65-73. [PMID: 22572591 DOI: 10.1016/j.expneurol.2012.04.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 03/20/2012] [Accepted: 04/23/2012] [Indexed: 11/25/2022]
Abstract
The analysis of neuronal networks, their interactions in resting condition as well as during brain activation have become of great interest for a better understanding of the signal processing of the brain during sensory stimulus or cognitive tasks. Parallel to the study of the functional networks and their dynamics, the underlying network structure is highly important as it provides the basis of the functional interaction. Moreover, under pathological conditions, some nodes in such a net may be impaired and the function of the whole network affected. Mechanisms such as functional deficit and improvement, and plastic reorganization are increasingly discussed in the context of existing structural and functional networks. While many of these aspects have been followed in human and clinical studies, the experimental range is limited for obvious reasons. Here, animal experimental studies are needed as they permit longer scan times and, moreover, comparison with invasive histology. Experimental non-invasive imaging modalities are now able to perform impressive contributions. In this review we try to highlight most recent new cutting-edge developments and applications in experimental neuroscience of functional and structural networks of the brain, relying on non-invasive imaging. We focus primarily on the potential of experimental Magnetic Resonance Imaging (MRI), but also touch upon micro positron emission tomography (μPET) and optical imaging developments where they are applicable to the topic of the present review.
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Affiliation(s)
- Mathias Hoehn
- In-vivo-NMR Laboratory, Max Planck Institute for Neurological Research, Cologne, Germany.
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PET molecular imaging in stem cell therapy for neurological diseases. Eur J Nucl Med Mol Imaging 2011; 38:1926-38. [DOI: 10.1007/s00259-011-1860-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 06/06/2011] [Indexed: 01/12/2023]
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