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Freire M, Gonzalez-Montoro A, Cañizares G, Rezaei A, Nuyts J, Berr SS, Williams MB, Benlloch JM, Gonzalez AJ. Experimental validation of a rodent PET scanner prototype based on a single LYSO crystal tube. IEEE Trans Radiat Plasma Med Sci 2022; 6:697-706. [PMID: 35909498 PMCID: PMC9328404 DOI: 10.1109/trpms.2021.3124448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
Improving sensitivity and spatial resolution in small animal Positron Emission Tomography imaging instrumentation constitutes one of the main goals of nuclear imaging research. These parameters are degraded by the presence of gaps between the detectors. The present manuscript experimentally validates our prototype of an edge-less pre-clinical PET system based on a single LYSO:Ce annulus with an inner diameter of 62 mm and 10 outer facets of 26 × 52 mm2. Scintillation light is read out by arrays of 8 × 8 SiPMs coupled to the facets, using a projection readout of the rows and columns signals. The readout provides accurate Depth of Interaction (DOI). We have implemented a calibration that mitigates the DOI-dependency of the transaxial and axial impact coordinates, and the energy photopeak gain. An energy resolution of 23.4 ± 1.8% was determined. Average spatial resolution of 1.4 ± 0.2 and 1.3 ± 0.4 mm FWHM were achieved for the radial and axial directions, respectively. We found a peak sensitivity of 3.8% at the system center, and a maximum NECR at 40.6 kcps for 0.27 mCi. The image quality was evaluated using reconstructed images of an array of sources and the NEMA image quality phantom was also studied.
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Affiliation(s)
- Marta Freire
- Instituto de Instrumentación para la Imagen Molecular (i3M-CSIC-UPV), Valencia, Spain
| | | | - Gabriel Cañizares
- Instituto de Instrumentación para la Imagen Molecular (i3M-CSIC-UPV), Valencia, Spain
| | - Ahmadreza Rezaei
- Department of Imaging and Pathology, Nuclear Medicine & Molecular imaging, KU Leuven, Leuven, Belgium
| | - Johan Nuyts
- Department of Imaging and Pathology, Nuclear Medicine & Molecular imaging, KU Leuven, Leuven, Belgium
| | - Stuart S Berr
- Department of Radiology and Medical Imaging, The University of Virginia, Charlottesville, Virginia, United States
| | - Mark B Williams
- Department of Radiology and Medical Imaging, The University of Virginia, Charlottesville, Virginia, United States
| | - Jose M Benlloch
- Instituto de Instrumentación para la Imagen Molecular (i3M-CSIC-UPV), Valencia, Spain
| | - Antonio J Gonzalez
- Instituto de Instrumentación para la Imagen Molecular (i3M-CSIC-UPV), Valencia, Spain
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2
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Tobey H, Lucas T, Paul S, Berr SS, Mehrkens B, Brolinson PG, Klein BG, Costa BM. Mechanoceutics Alters Alzheimer's Disease Phenotypes in Transgenic Rats: A Pilot Study. J Alzheimers Dis 2021; 74:421-427. [PMID: 32039851 DOI: 10.3233/jad-191071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Current advancements in neurovascular biology relates a mechanoceutics treatment, known as cranial osteopathic manipulation (COM), Alzheimer's disease (AD). COM could be used as an evidence-based treatment strategy to improve the symptoms of AD if molecular mechanisms, which currently remain unclear, are elucidated. In the present pilot study, using transgenic rats, we have identified COM mediated changes in behavioral and biochemical parameters associated with AD phenotypes. We expect these changes may have functional implications that might account for improved clinical outcomes of COM treatment. Further investigations on COM will be helpful to establish an adjunct treatment for AD.
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Affiliation(s)
- Hope Tobey
- Edward Via Virginia College of Osteopathic Medicine, Blacksburg, VA, USA
| | - Tyler Lucas
- Edward Via Virginia College of Osteopathic Medicine, Blacksburg, VA, USA
| | - Soumen Paul
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Stuart S Berr
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Brittney Mehrkens
- Center for One Health Research, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, USA
| | | | - Bradley G Klein
- Center for One Health Research, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, USA
| | - Blaise M Costa
- Edward Via Virginia College of Osteopathic Medicine, Blacksburg, VA, USA.,Center for One Health Research, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, USA
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3
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Sheybani ND, Breza VR, Paul S, McCauley KS, Berr SS, Miller GW, Neumann KD, Price RJ. ImmunoPET-informed sequence for focused ultrasound-targeted mCD47 blockade controls glioma. J Control Release 2021; 331:19-29. [PMID: 33476735 PMCID: PMC7946780 DOI: 10.1016/j.jconrel.2021.01.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 01/10/2021] [Accepted: 01/12/2021] [Indexed: 12/11/2022]
Abstract
Phagocytic immunotherapies such as CD47 blockade have emerged as promising strategies for glioblastoma (GB) therapy, but the blood brain/tumor barriers (BBB/BTB) pose a persistent challenge for mCD47 delivery that can be overcome by focused ultrasound (FUS)-mediated BBB/BTB disruption. We here leverage immuno-PET imaging to determine how timing of [89Zr]-mCD47 injection relative to FUS impacts antibody penetrance into orthotopic murine gliomas. We then design and implement a rational paradigm for combining FUS and mCD47 for glioma therapy. We demonstrate that timing of antibody injection relative to FUS BBB/BTB disruption is a critical determinant of mCD47 access, with post-FUS injection conferring superlative antibody delivery to gliomas. We also show that mCD47 delivery across the BBB/BTB with repeat sessions of FUS can significantly constrain tumor outgrowth and extend survival in glioma-bearing mice. This study generates provocative insights for ongoing pre-clinical and clinical evaluations of FUS-mediated antibody delivery to brain tumors. Moreover, our results confirm that mCD47 delivery with FUS is a promising therapeutic strategy for GB therapy.
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Affiliation(s)
- Natasha D Sheybani
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, United States of America.
| | - Victoria R Breza
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, United States of America
| | - Soumen Paul
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA 22908, United States of America
| | - Katelyenn S McCauley
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA 22908, United States of America
| | - Stuart S Berr
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA 22908, United States of America
| | - G Wilson Miller
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, United States of America; Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA 22908, United States of America
| | - Kiel D Neumann
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA 22908, United States of America
| | - Richard J Price
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, United States of America; Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA 22908, United States of America.
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4
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Freire M, Gonzalez-Montoro A, Cañizares G, Berr SS, Vidal LF, Hernandez L, Gonzalez AJ. Calibration Methodology of an Edgeless PET System Prototype. IEEE Nucl Sci Symp Conf Rec (1997) 2020; 2020:10.1109/NSS/MIC42677.2020.9508042. [PMID: 34908824 PMCID: PMC8667022 DOI: 10.1109/nss/mic42677.2020.9508042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Instrumentation research in small animal Positron Emission Tomography (PET) imaging is driven by improving timing, spatial resolution and sensitivity. Conventional PET scanners are built of multiple detectors placed in a cylindrical geometry with gaps between them in both the transaxial and axial planes. These gaps decrease sensitivity and degrade spatial resolution towards the edges of the system field of view (FOV). To mitigate these problems, we have designed and validated an edgeless pre-clinical PET system based on a single LYSO annulus with an inner diameter of 62 mm and 10 outer facets of 26 × 52 mm2 each. The scintillation light is read out using the row and columns of Silicon Photomultipliers (SiPMs) mounted in magnetic-field compatible PCBs. The objective of this work is to provide a calibration method for this system. The particular design of the annulus produces some undesirable effects in the light distributions (LD) at the module joints, which needs to be addressed. Nevertheless, after calibration, the system allows one to properly retrieve both, the energy and 3D photon impact positions.
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Affiliation(s)
- Marta Freire
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | - Andrea Gonzalez-Montoro
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | - Gabriel Cañizares
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | | | - Luis F Vidal
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | - Liczandro Hernandez
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | - Antonio J Gonzalez
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
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5
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Cui D, Drake JC, Wilson RJ, Shute RJ, Lewellen B, Zhang M, Zhao H, Sabik OL, Onengut S, Berr SS, Rich SS, Farber CR, Yan Z. A novel voluntary weightlifting model in mice promotes muscle adaptation and insulin sensitivity with simultaneous enhancement of autophagy and mTOR pathway. FASEB J 2020; 34:7330-7344. [PMID: 32304342 DOI: 10.1096/fj.201903055r] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/17/2020] [Accepted: 03/04/2020] [Indexed: 12/23/2022]
Abstract
Our understanding of the molecular mechanisms underlying adaptations to resistance exercise remains elusive despite the significant biological and clinical relevance. We developed a novel voluntary mouse weightlifting model, which elicits squat-like activities against adjustable load during feeding, to investigate the resistance exercise-induced contractile and metabolic adaptations. RNAseq analysis revealed that a single bout of weightlifting induced significant transcriptome responses of genes that function in posttranslational modification, metabolism, and muscle differentiation in recruited skeletal muscles, which were confirmed by increased expression of fibroblast growth factor-inducible 14 (Fn14), Down syndrome critical region 1 (Dscr1) and Nuclear receptor subfamily 4, group A, member 3 (Nr4a3) genes. Long-term (8 weeks) voluntary weightlifting training resulted in significantly increases of muscle mass, protein synthesis (puromycin incorporation in SUnSET assay) and mTOR pathway protein expression (raptor, 4e-bp-1, and p70S6K proteins) along with enhanced muscle power (specific torque and contraction speed), but not endurance capacity, mitochondrial biogenesis, and fiber type transformation. Importantly, weightlifting training profound improved whole-body glucose clearance and skeletal muscle insulin sensitivity along with enhanced autophagy (increased LC3 and LC3-II/I ratio, and decreased p62/Sqstm1). These data suggest that resistance training in mice promotes muscle adaptation and insulin sensitivity with simultaneous enhancement of autophagy and mTOR pathway.
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Affiliation(s)
- Di Cui
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA.,Key Laboratory of Adolescent and Exercise Intervention, Ministry of Education, East China Normal University, Shanghai, China
| | - Joshua C Drake
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Rebecca J Wilson
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA.,Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Robert J Shute
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Bevan Lewellen
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Mei Zhang
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA.,Departments of Medicine, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Henan Zhao
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Olivia L Sabik
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, USA.,Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Suna Onengut
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Stuart S Berr
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Stephen S Rich
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Charles R Farber
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, USA.,Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA, USA.,Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Zhen Yan
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA.,Departments of Medicine, University of Virginia School of Medicine, Charlottesville, VA, USA.,Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, USA
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6
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Tobey H, Lucas T, Bledsoe D, Mykins M, Campbell C, Berr SS, Sasser T, Helm R, Brolinson PG, Klein BG, Costa BM. Effect of Osteopathic Cranial Manipulative Medicine on an Aged Rat Model of Alzheimer Disease. J Am Osteopath Assoc 2019; 119:2753340. [PMID: 31613309 PMCID: PMC8425714 DOI: 10.7556/jaoa.2019.121] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
CONTEXT In the aging brain, reduction in the pulsation of cerebral vasculature and fluid circulation causes impairment in the fluid exchange between different compartments and lays a foundation for the neuroinflammation that results in Alzheimer disease (AD). The knowledge that lymphatic vessels in the central nervous system play a role in the clearance of brain-derived metabolic waste products opens an unprecedented capability to increase the clearance of macromolecules such as amyloid β proteins. However, currently there is no pharmacologic mechanism available to increase fluid circulation in the aging brain. OBJECTIVE To demonstrate the influence of an osteopathic cranial manipulative medicine (OCMM) technique, specifically, compression of the fourth ventricle, on spatial memory and changes in substrates associated with mechanisms of metabolic waste clearance in the central nervous system using the naturally aged rat model of AD. RESULTS Significant improvement was found in spatial memory in 6 rats after 7 days of OCMM sessions. Live animal positron emission tomographic imaging and immunoassays revealed that OCMM reduced amyloid β levels, activated astrocytes, and improved neurotransmission in the aged rat brains. CONCLUSION These findings demonstrate the molecular mechanism of OCMM in aged rats. This study and further investigations will help physicians promote OCMM as an evidence-based adjunctive treatment for patients with AD.
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7
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Gonzalez AJ, Berr SS, Cañizares G, Gonzalez-Montoro A, Orero A, Correcher C, Rezaei A, Nuyts J, Sanchez F, Majewski S, Benlloch JM. Feasibility Study of a Small Animal PET Insert Based on a Single LYSO Monolithic Tube. Front Med (Lausanne) 2018; 5:328. [PMID: 30547030 PMCID: PMC6279866 DOI: 10.3389/fmed.2018.00328] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 11/09/2018] [Indexed: 11/26/2022] Open
Abstract
There are drawbacks with using a Positron Emission Tomography (PET) scanner design employing the traditional arrangement of multiple detectors in an array format. Typically PET systems are constructed with many regular gaps between the detector modules in a ring or box configuration, with additional axial gaps between the rings. Although this has been significantly reduced with the use of the compact high granularity SiPM photodetector technology, such a scanner design leads to a decrease in the number of annihilation photons that are detected causing lower scanner sensitivity. Moreover, the ability to precisely determine the line of response (LOR) along which the positron annihilated is diminished closer to the detector edges because the spatial resolution there is degraded due to edge effects. This happens for both monolithic based designs, caused by the truncation of the scintillation light distribution, but also for detector blocks that use crystal arrays with a number of elements that are larger than the number of photosensors and, therefore, make use of the light sharing principle. In this report we present a design for a small-animal PET scanner based on a single monolithic annulus-like scintillator that can be used as a PET insert in high-field Magnetic Resonance systems. We provide real data showing the performance improvement when edge-less modules are used. We also describe the specific proposed design for a rodent scanner that employs facetted outside faces in a single LYSO tube. In a further step, in order to support and prove the proposed edgeless geometry, simulations of that scanner have been performed and lately reconstructed showing the advantages of the design.
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Affiliation(s)
- Antonio J. Gonzalez
- Detector for Molecular Imaging Lab (DMIL), Instituto de Instrumentacion para Imagen Molecular (i3M), Centro Mixto CSIC - Universitat Politècnica de València, Valencia, Spain
| | - Stuart S. Berr
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, United States
| | - Gabriel Cañizares
- Detector for Molecular Imaging Lab (DMIL), Instituto de Instrumentacion para Imagen Molecular (i3M), Centro Mixto CSIC - Universitat Politècnica de València, Valencia, Spain
| | - Andrea Gonzalez-Montoro
- Detector for Molecular Imaging Lab (DMIL), Instituto de Instrumentacion para Imagen Molecular (i3M), Centro Mixto CSIC - Universitat Politècnica de València, Valencia, Spain
| | | | | | - Ahmadreza Rezaei
- Nuclear Medicine and Medical Imaging Research CenterKU Leuven, Leuven, Belgium
| | - Johan Nuyts
- Nuclear Medicine and Medical Imaging Research CenterKU Leuven, Leuven, Belgium
- MoSAIC, Molecular Small Animal Imaging Center, KU Leuven – University of LeuvenLeuven, Belgium
| | - Filomeno Sanchez
- Detector for Molecular Imaging Lab (DMIL), Instituto de Instrumentacion para Imagen Molecular (i3M), Centro Mixto CSIC - Universitat Politècnica de València, Valencia, Spain
| | - Stan Majewski
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, United States
| | - Jose M. Benlloch
- Detector for Molecular Imaging Lab (DMIL), Instituto de Instrumentacion para Imagen Molecular (i3M), Centro Mixto CSIC - Universitat Politècnica de València, Valencia, Spain
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8
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Grainger AT, Tustison NJ, Qing K, Roy R, Berr SS, Shi W. Deep learning-based quantification of abdominal fat on magnetic resonance images. PLoS One 2018; 13:e0204071. [PMID: 30235253 PMCID: PMC6147491 DOI: 10.1371/journal.pone.0204071] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 08/09/2018] [Indexed: 01/02/2023] Open
Abstract
Obesity is increasingly prevalent and associated with increased risk of developing type 2 diabetes, cardiovascular diseases, and cancer. Magnetic resonance imaging (MRI) is an accurate method for determination of body fat volume and distribution. However, quantifying body fat from numerous MRI slices is tedious and time-consuming. Here we developed a deep learning-based method for measuring visceral and subcutaneous fat in the abdominal region of mice. Congenic mice only differ from C57BL/6 (B6) Apoe knockout (Apoe-/-) mice in chromosome 9 that is replaced by C3H/HeJ genome. Male congenic mice had lighter body weight than B6-Apoe-/- mice after being fed 14 weeks of Western diet. Axial and coronal T1-weighted sequencing at 1-mm-thickness and 1-mm-gap was acquired with a 7T Bruker ClinScan scanner. A deep learning approach was developed for segmenting visceral and subcutaneous fat based on the U-net architecture made publicly available through the open-source ANTsRNet library—a growing repository of well-known neural networks. The volumes of subcutaneous and visceral fat measured through our approach were highly comparable with those from manual measurements. The Dice score, root-mean-square error (RMSE), and correlation analysis demonstrated the similarity between two methods in quantifying visceral and subcutaneous fat. Analysis with the automated method showed significant reductions in volumes of visceral and subcutaneous fat but not non-fat tissues in congenic mice compared to B6 mice. These results demonstrate the accuracy of deep learning in quantification of abdominal fat and its significance in determining body weight.
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Affiliation(s)
- Andrew T. Grainger
- Departments of Biochemistry & Molecular Genetics, University of Virginia, Charlottesville, Virginia, United States of America
| | - Nicholas J. Tustison
- Radiology & Medical Imaging, University of Virginia, Charlottesville, Virginia, United States of America
| | - Kun Qing
- Radiology & Medical Imaging, University of Virginia, Charlottesville, Virginia, United States of America
| | - Rene Roy
- Radiology & Medical Imaging, University of Virginia, Charlottesville, Virginia, United States of America
| | - Stuart S. Berr
- Radiology & Medical Imaging, University of Virginia, Charlottesville, Virginia, United States of America
| | - Weibin Shi
- Departments of Biochemistry & Molecular Genetics, University of Virginia, Charlottesville, Virginia, United States of America
- Radiology & Medical Imaging, University of Virginia, Charlottesville, Virginia, United States of America
- * E-mail:
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9
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Byrne FL, Hargett SR, Lahiri S, Roy RJ, Berr SS, Caldwell SH, Hoehn KL. Serial MRI Imaging Reveals Minimal Impact of Ketogenic Diet on Established Liver Tumor Growth. Cancers (Basel) 2018; 10:E312. [PMID: 30189621 PMCID: PMC6162796 DOI: 10.3390/cancers10090312] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 08/29/2018] [Accepted: 09/04/2018] [Indexed: 11/16/2022] Open
Abstract
Rodent models of liver tumorigenesis have reproducibly shown that dietary sugar intake is a powerful driver of liver tumor initiation and growth. In contrast, dietary sugar restriction with ketogenic diets or calorie restriction generally prevents liver tumor formation. Ketogenic diet is viewed positively as a therapeutic adjuvant; however, most ketogenic diet studies described to date have been performed in prevention mode rather than treatment mode. Therefore, it remains unclear whether a ketogenic diet can be administered in late stages of disease to stall or reverse liver tumor growth. To model the clinically relevant treatment mode, we administered a ketogenic diet to mice after liver tumor initiation and monitored tumor growth by magnetic resonance imaging (MRI). Male C57BL/6 mice were injected with diethylnitrosamine (DEN) at 2 weeks of age and fed a chow diet until 39 weeks of age, when they underwent MRI imaging to detect liver tumors. Mice were then randomised into two groups and fed either a chow diet or switched to a ketogenic diet from 40⁻48 weeks of age. Serial MRIs were performed at 44 and 48 weeks of age. All mice had tumors at study completion and there were no differences in total tumor burden between diet groups. Although a ketogenic diet has marked protective effects against DEN-induced liver tumourigenesis in this mouse model, these data demonstrate that ketogenic diet cannot stop the progression of established liver tumors.
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Affiliation(s)
- Frances L Byrne
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Stefan R Hargett
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA.
| | - Sujoy Lahiri
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA.
| | - R Jack Roy
- Department of Radiology, University of Virginia, Health System, Charlottesville, VA 22908, USA.
| | - Stuart S Berr
- Department of Radiology, University of Virginia, Health System, Charlottesville, VA 22908, USA.
| | - Stephen H Caldwell
- Department of Medicine, University of Virginia, Charlottesville, VA 22908, USA.
| | - Kyle L Hoehn
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA.
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10
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Cheng B, He H, Huang T, Berr SS, He J, Fan D, Zhang J, Xu P. Gold Nanosphere Gated Mesoporous Silica Nanoparticle Responsive to Near-Infrared Light and Redox Potential as a Theranostic Platform for Cancer Therapy. J Biomed Nanotechnol 2016; 12:435-49. [PMID: 26949379 DOI: 10.1166/jbn.2016.2195] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A gold/mesoporous silica hybrid nanoparticle (GoMe), which possesses the best of both conventional gold nanoparticles and mesoporous silica nanoparticles, such as excellent photothermal converting ability as well as high drug loading capacity and triggerable drug release, has been developed. In contrast to gold nanorod and other heat generating gold nanoparticles, GoMe is photothermal stable and can be repetitively activated through NIR irradiation. Doxorubicin loaded GoMe (DOX@GoMe) is sensitive to both NIR irradiation and intracellularly elevated redox potential. DOX@GoMe coupled with NIR irradiation exhibits a synergistic effect of photothermal therapy and chemotherapy in killing cancer cells. Furthermore, 64Cu-labeled GoMe can successfully detect the existence of clinically relevant spontaneous lung tumors in a urethane-induced lung cancer mouse model through PET imaging. Altogether, GoMe can be utilized as an effective theranostic platform for cancer therapy.
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11
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Li Y, Huang T, Zhang X, Zhong M, Walker NN, He J, Berr SS, Keller SR, Kundu BK. Determination of Fatty Acid Metabolism with Dynamic [
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C]Palmitate Positron Emission Tomography of Mouse Heart In Vivo. Mol Imaging 2015. [DOI: 10.2310/7290.2015.00024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Yinlin Li
- From the Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA; Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA; Cardiovascular Research Center, University of Virginia, Charlottesville, VA; and School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Tao Huang
- From the Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA; Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA; Cardiovascular Research Center, University of Virginia, Charlottesville, VA; and School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Xinyue Zhang
- From the Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA; Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA; Cardiovascular Research Center, University of Virginia, Charlottesville, VA; and School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Min Zhong
- From the Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA; Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA; Cardiovascular Research Center, University of Virginia, Charlottesville, VA; and School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Natalie N. Walker
- From the Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA; Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA; Cardiovascular Research Center, University of Virginia, Charlottesville, VA; and School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Jiang He
- From the Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA; Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA; Cardiovascular Research Center, University of Virginia, Charlottesville, VA; and School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Stuart S. Berr
- From the Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA; Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA; Cardiovascular Research Center, University of Virginia, Charlottesville, VA; and School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Susanna R. Keller
- From the Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA; Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA; Cardiovascular Research Center, University of Virginia, Charlottesville, VA; and School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Bijoy K. Kundu
- From the Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA; Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA; Cardiovascular Research Center, University of Virginia, Charlottesville, VA; and School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
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12
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Li Y, Huang T, Zhang X, Zhong M, Walker NN, He J, Berr SS, Keller SR, Kundu BK. Determination of Fatty Acid Metabolism with Dynamic [11C]Palmitate Positron Emission Tomography of Mouse Heart In Vivo. Mol Imaging 2015; 14:516-525. [PMID: 26462138 PMCID: PMC4625801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023] Open
Abstract
The goal of this study was to establish a quantitative method for measuring fatty acid (FA) metabolism with partial volume (PV) and spill-over (SP) corrections using dynamic [(11)C]palmitate positron emission tomographic (PET) images of mouse heart in vivo. Twenty-minute dynamic [(11)C]palmitate PET scans of four 18- to 20-week-old male C57BL/6 mice under isoflurane anesthesia were performed using a Focus F-120 PET scanner. A model-corrected blood input function, by which the input function with SP and PV corrections and the metabolic rate constants (k1-k5) are simultaneously estimated from the dynamic [(11)C]palmitate PET images of mouse hearts in a four-compartment tracer kinetic model, was used to determine rates of myocardial fatty acid oxidation (MFAO), myocardial FA esterification, myocardial FA use, and myocardial FA uptake. The MFAO thus measured in C57BL/6 mice was 375.03 ± 43.83 nmol/min/g. This compares well to the MFAO measured in perfused working C57BL/6 mouse hearts ex vivo of about 350 nmol/g/min and 400 nmol/min/g. FA metabolism was measured for the first time in mouse heart in vivo using dynamic [(11)C]palmitate PET in a four-compartment tracer kinetic model. MFAO obtained with this model was validated by results previously obtained with mouse hearts ex vivo.
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Affiliation(s)
- Yinlin Li
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
- School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Tao Huang
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Xinyue Zhang
- School of Mechatronic Engineering, Beijing Institute of Technology, Beijing, China
| | - Min Zhong
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Natalie N. Walker
- Department of Medicine, Division of Endocrinology and Metabolism, University of Virginia, VA, USA
| | - Jiang He
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Stuart S. Berr
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Susanna R. Keller
- Department of Medicine, Division of Endocrinology and Metabolism, University of Virginia, VA, USA
| | - Bijoy K. Kundu
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
- Cardiovascular Research Center, University of Virginia, Charlottesville, VA, USA
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13
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Banizs AB, Huang T, Dryden K, Berr SS, Stone JR, Nakamoto RK, Shi W, He J. In vitro evaluation of endothelial exosomes as carriers for small interfering ribonucleic acid delivery. Int J Nanomedicine 2014; 9:4223-30. [PMID: 25214786 PMCID: PMC4159392 DOI: 10.2147/ijn.s64267] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Exosomes, one subpopulation of nanosize extracellular vesicles derived from multivesicular bodies, ranging from 30 to 150 nm in size, emerged as promising carriers for small interfering ribonucleic acid (siRNA) delivery, as they are capable of transmitting molecular messages between cells through carried small noncoding RNAs, messenger RNAs, deoxyribonucleic acids, and proteins. Endothelial cells are involved in a number of important biological processes, and are a major source of circulating exosomes. In this study, we prepared exosomes from endothelial cells and evaluated their capacity to deliver siRNA into primary endothelial cells. Exosomes were isolated and purified by sequential centrifugation and ultracentrifugation from cultured mouse aortic endothelial cells. Similar to exosome particles from other cell sources, endothelial exosomes are nanometer-size vesicles, examined by both the NanoSight instrument and transmission electron microscopy. Enzyme-linked immunosorbent assay analysis confirmed the expression of two exosome markers: CD9 and CD63. Flow cytometry and fluorescence microscopy studies demonstrated that endothelial exosomes were heterogeneously distributed within cells. In a gene-silencing study with luciferase-expressing endothelial cells, exosomes loaded with siRNA inhibited luciferase expression by more than 40%. In contrast, siRNA alone and control siRNA only suppressed luciferase expression by less than 15%. In conclusion, we demonstrated that endothelial exosomes have the capability to accommodate and deliver short foreign nucleic acids into endothelial cells.
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Affiliation(s)
- Anna B Banizs
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Tao Huang
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Kelly Dryden
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, USA
| | - Stuart S Berr
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - James R Stone
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Robert K Nakamoto
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, USA
| | - Weibin Shi
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Jiang He
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
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14
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Stout D, Berr SS, LeBlanc A, Kalen JD, Osborne D, Price J, Schiffer W, Kuntner C, Wall J. Guidance for methods descriptions used in preclinical imaging papers. Mol Imaging 2013; 12:1-15. [PMID: 23920252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023] Open
Abstract
Preclinical molecular imaging is a rapidly growing field, where new imaging systems, methods, and biological findings are constantly being developed or discovered. Imaging systems and the associated software usually have multiple options for generating data, which is often overlooked but is essential when reporting the methods used to create and analyze data. Similarly, the ways in which animals are housed, handled, and treated to create physiologically based data must be well described in order that the findings be relevant, useful, and reproducible. There are frequently new developments for metabolic imaging methods. Thus, specific reporting requirements are difficult to establish; however, it remains essential to adequately report how the data have been collected, processed, and analyzed. To assist with future manuscript submissions, this article aims to provide guidelines of what details to report for several of the most common imaging modalities. Examples are provided in an attempt to give comprehensive, succinct descriptions of the essential items to report about the experimental process.
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15
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Stout D, Berr SS, LeBlanc A, Kalen JD, Osborne D, Price J, Schiffer W, Kuntner C, Wall J. Guidance for Methods Descriptions Used in Preclinical Imaging Papers. Mol Imaging 2013. [DOI: 10.2310/7290.2013.00055] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- David Stout
- From the Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA; Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA; Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN; Small Animal Imaging Program/Laboratory Animal Sciences Program/SAIC-Frederick, Frederick National Laboratory for Cancer Research, Frederick, MD; Departments of Medicine
| | - Stuart S. Berr
- From the Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA; Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA; Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN; Small Animal Imaging Program/Laboratory Animal Sciences Program/SAIC-Frederick, Frederick National Laboratory for Cancer Research, Frederick, MD; Departments of Medicine
| | - Amy LeBlanc
- From the Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA; Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA; Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN; Small Animal Imaging Program/Laboratory Animal Sciences Program/SAIC-Frederick, Frederick National Laboratory for Cancer Research, Frederick, MD; Departments of Medicine
| | - Joseph D. Kalen
- From the Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA; Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA; Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN; Small Animal Imaging Program/Laboratory Animal Sciences Program/SAIC-Frederick, Frederick National Laboratory for Cancer Research, Frederick, MD; Departments of Medicine
| | - Dustin Osborne
- From the Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA; Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA; Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN; Small Animal Imaging Program/Laboratory Animal Sciences Program/SAIC-Frederick, Frederick National Laboratory for Cancer Research, Frederick, MD; Departments of Medicine
| | - Julie Price
- From the Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA; Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA; Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN; Small Animal Imaging Program/Laboratory Animal Sciences Program/SAIC-Frederick, Frederick National Laboratory for Cancer Research, Frederick, MD; Departments of Medicine
| | - Wynne Schiffer
- From the Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA; Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA; Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN; Small Animal Imaging Program/Laboratory Animal Sciences Program/SAIC-Frederick, Frederick National Laboratory for Cancer Research, Frederick, MD; Departments of Medicine
| | - Claudia Kuntner
- From the Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA; Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA; Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN; Small Animal Imaging Program/Laboratory Animal Sciences Program/SAIC-Frederick, Frederick National Laboratory for Cancer Research, Frederick, MD; Departments of Medicine
| | - Jonathan Wall
- From the Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA; Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA; Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN; Small Animal Imaging Program/Laboratory Animal Sciences Program/SAIC-Frederick, Frederick National Laboratory for Cancer Research, Frederick, MD; Departments of Medicine
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16
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Sen S, Kundu BK, Wu HCJ, Hashmi SS, Guthrie P, Locke LW, Roy RJ, Matherne GP, Berr SS, Terwelp M, Scott B, Carranza S, Frazier OH, Glover DK, Dillmann WH, Gambello MJ, Entman ML, Taegtmeyer H. Glucose regulation of load-induced mTOR signaling and ER stress in mammalian heart. J Am Heart Assoc 2013; 2:e004796. [PMID: 23686371 PMCID: PMC3698799 DOI: 10.1161/jaha.113.004796] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Changes in energy substrate metabolism are first responders to hemodynamic stress in the heart. We have previously shown that hexose-6-phosphate levels regulate mammalian target of rapamycin (mTOR) activation in response to insulin. We now tested the hypothesis that inotropic stimulation and increased afterload also regulate mTOR activation via glucose 6-phosphate (G6P) accumulation. METHODS AND RESULTS We subjected the working rat heart ex vivo to a high workload in the presence of different energy-providing substrates including glucose, glucose analogues, and noncarbohydrate substrates. We observed an association between G6P accumulation, mTOR activation, endoplasmic reticulum (ER) stress, and impaired contractile function, all of which were prevented by pretreating animals with rapamycin (mTOR inhibition) or metformin (AMPK activation). The histone deacetylase inhibitor 4-phenylbutyrate, which relieves ER stress, also improved contractile function. In contrast, adding the glucose analogue 2-deoxy-d-glucose, which is phosphorylated but not further metabolized, to the perfusate resulted in mTOR activation and contractile dysfunction. Next we tested our hypothesis in vivo by transverse aortic constriction in mice. Using a micro-PET system, we observed enhanced glucose tracer analog uptake and contractile dysfunction preceding dilatation of the left ventricle. In contrast, in hearts overexpressing SERCA2a, ER stress was reduced and contractile function was preserved with hypertrophy. Finally, we examined failing human hearts and found that mechanical unloading decreased G6P levels and ER stress markers. CONCLUSIONS We propose that glucose metabolic changes precede and regulate functional (and possibly also structural) remodeling of the heart. We implicate a critical role for G6P in load-induced mTOR activation and ER stress.
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Affiliation(s)
- Shiraj Sen
- Division of Cardiology, Department of Internal Medicine, The University of Texas Medical School at Houston, Houston, TX 77030, USA
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17
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Xiao L, Zhang Y, Berr SS, Chordia MD, Pramoonjago P, Pu L, Pan D. A novel near-infrared fluorescence imaging probe for in vivo neutrophil tracking. Mol Imaging 2012; 11:372-382. [PMID: 22954181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023] Open
Abstract
The development and validation of a multiscopic near-infrared fluorescence (NIRF) probe, cinnamoyl-F-(D)L-F-(D)L-F-PEG-cyanine7 (cFlFlF-PEG-Cy7), that targets formyl peptide receptor on neutrophils using a mice ear inflammation model is described. Acute inflammation was induced in mice by topical application of phorbol-12-myristate-13-acetate to left ears 24 hours before probe administration. Noninvasive NIRF imaging was longitudinally performed up to 24 hours following probe injection. The in vivo neutrophil-targeting specificity of the probe was characterized by a blocking study with preadministration of excess nonfluorescent peptide cFlFlF-PEG and by an imaging study with a scrambled peptide probe cLFFFL-PEG-Cy7. NIRF imaging of mice injected with cinnamoyl-L-F-F-F-L-PEG-cyanine7 (cFlFlF-PEG-Cy7) revealed that the fluorescence intensity for inflamed left ears was approximately fourfold higher than that of control right ears at 24 hours postinjection. In comparison, the ratios acquired with the scrambled probe and from the blocking study were 1.5- and 2-fold at 24 hours postinjection, respectively. Moreover, a microscopic immunohistologic study confirmed that the NIRF signal of cFlFlF-PEG-Cy7 was associated with activated neutrophils in the inflammatory tissue. With this probe, in vivo neutrophil chemotaxis could be correlatively imaged macroscopically in live animals and microscopically at tissue and cellular levels.
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Affiliation(s)
- Li Xiao
- Department of Radiology, The University of Virginia, Charlottesville, VA 22908, USA
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18
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Xiao L, Zhang Y, Berr SS, Chordia MD, Pramoonjago P, Pu L, Pan D. A Novel Near-Infrared Fluorescence Imaging Probe for in Vivo Neutrophil Tracking. Mol Imaging 2012. [DOI: 10.2310/7290.2011.00054] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Li Xiao
- From the Departments of Radiology, Chemistry, and Pathology, The University of Virginia, Charlottesville, VA
| | - Yi Zhang
- From the Departments of Radiology, Chemistry, and Pathology, The University of Virginia, Charlottesville, VA
| | - Stuart S. Berr
- From the Departments of Radiology, Chemistry, and Pathology, The University of Virginia, Charlottesville, VA
| | - Mahendra D. Chordia
- From the Departments of Radiology, Chemistry, and Pathology, The University of Virginia, Charlottesville, VA
| | - Patcharin Pramoonjago
- From the Departments of Radiology, Chemistry, and Pathology, The University of Virginia, Charlottesville, VA
| | - Lin Pu
- From the Departments of Radiology, Chemistry, and Pathology, The University of Virginia, Charlottesville, VA
| | - Dongfeng Pan
- From the Departments of Radiology, Chemistry, and Pathology, The University of Virginia, Charlottesville, VA
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19
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Locke LW, Mayo MW, Yoo AD, Williams MB, Berr SS. PET imaging of tumor associated macrophages using mannose coated 64Cu liposomes. Biomaterials 2012; 33:7785-93. [PMID: 22840225 DOI: 10.1016/j.biomaterials.2012.07.022] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 07/09/2012] [Indexed: 01/25/2023]
Abstract
Macrophages within the tumor microenvironment (TAMs) have been shown to play a major role in the growth and spread of many types of cancer. Cancer cells produce cytokines that cause macrophages to express scavenger receptors (e.g. the mannose receptor) and factors that facilitate tissue and blood vessel growth, suppress T cell mediated anti-tumor activity, and express enzymes that can break down the extracellular matrix, thereby promoting metastasis. We have designed a mannosylated liposome (MAN-LIPs) and show that it accumulates in TAMs in a mouse model of pulmonary adenocarcinoma. These liposomes are loaded with (64)Cu to allow tracking by PET imaging, and contain a fluorescent dye in the lipid bilayer permitting subsequent fluorescence microscopy. We injected these liposomes into a mouse model of lung cancer. In vivo PET images were acquired 6 h after injection followed by the imaging of select excised organs. MAN-LIPs accumulated in TAMs and exhibited little accumulation in remote lung areas. MAN-LIPs are a promising new vehicle for the delivery of imaging agents to lung TAMs. In addition to imaging, MAN-LIPs hold the potential for delivery of therapeutic agents to the tumor microenvironment.
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Affiliation(s)
- Landon W Locke
- Department of Biomedical Engineering, The University of Virginia, Charlottesville, VA 22908, USA
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20
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West AM, Anderson JD, Epstein FH, Meyer CH, Hagspiel KD, Berr SS, Harthun NL, Weltman AL, Annex BH, Kramer CM. Percutaneous intervention in peripheral artery disease improves calf muscle phosphocreatine recovery kinetics: a pilot study. Vasc Med 2012; 17:3-9. [PMID: 22363013 DOI: 10.1177/1358863x11431837] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We hypothesized that percutaneous intervention in the affected lower extremity artery would improve calf muscle perfusion and cellular metabolism in patients with claudication and peripheral artery disease (PAD) as measured by magnetic resonance imaging (MRI) and spectroscopy (MRS). Ten patients with symptomatic PAD (mean ± SD: age 57 ± 9 years; ankle-brachial index (ABI) 0.62 ± 0.17; seven males) were studied 2 months before and 10 months after lower extremity percutaneous intervention. Calf muscle phosphocreatine recovery time constant (PCr) in the revascularized leg was measured by (31)P MRS immediately after symptom-limited exercise on a 1.5-T scanner. Calf muscle perfusion was measured using first-pass gadolinium-enhanced MRI at peak exercise. A 6-minute walk and treadmill test were performed. The PCr recovery time constant improved significantly following intervention (91 ± 33 s to 52 ± 34 s, p < 0.003). Rest ABI also improved (0.62 ± 0.17 to 0.93 ± 0.25, p < 0.003). There was no difference in MRI-measured tissue perfusion or exercise parameters, although the study was underpowered for these endpoints. In conclusion, in this pilot study, successful large vessel percutaneous intervention in patients with symptomatic claudication, results in improved ABI and calf muscle phosphocreatine recovery kinetics.
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Affiliation(s)
- Amy M West
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, VA 22908, USA
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21
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Beyers RJ, Smith RS, Xu Y, Piras BA, Salerno M, Berr SS, Meyer CH, Kramer CM, French BA, Epstein FH. T2-weighted MRI of post-infarct myocardial edema in mice. Magn Reson Med 2011. [DOI: 10.1002/mrm.24160] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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22
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West AM, Pesch AJ, Mehta N, Anderson JD, Epstein FH, Meyer CH, Hagspiel KD, Berr SS, Harthun NL, Hunter JR, DiMaria JM, Christopher JM, Kramer CM. Changes in atherosclerotic plaque composition assessed by MRI in the superficial femoral artery with two years of lipid lowering therapy. J Cardiovasc Magn Reson 2011. [PMCID: PMC3106898 DOI: 10.1186/1532-429x-13-s1-p382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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23
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West AM, Anderson JD, Meyer CH, Epstein FH, Wang H, Hagspiel KD, Berr SS, Harthun NL, DiMaria JM, Hunter JR, Christopher JM, Chew JD, Winberry GB, Kramer CM. The effect of ezetimibe on peripheral arterial atherosclerosis depends upon statin use at baseline. Atherosclerosis 2011; 218:156-62. [PMID: 21570685 PMCID: PMC3157540 DOI: 10.1016/j.atherosclerosis.2011.04.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 03/22/2011] [Accepted: 04/04/2011] [Indexed: 11/23/2022]
Abstract
BACKGROUND Both statins and ezetimibe lower LDL-C, but ezetimibe's effect on atherosclerosis is controversial. We hypothesized that lowering LDL-C cholesterol by adding ezetimibe to statin therapy would regress atherosclerosis measured by magnetic resonance imaging (MRI) in the superficial femoral artery (SFA) in peripheral arterial disease (PAD). METHODS Atherosclerotic plaque volume was measured in the proximal 15-20 cm of the SFA in 67 PAD patients (age 63 ± 10, ABI 0.69 ± 0.14) at baseline and annually × 2. Statin-naïve patients (n=34) were randomized to simvastatin 40 mg (S, n=16) or simvastatin 40 mg+ezetimibe 10mg (S+E, n=18). Patients already on statins but with LDL-C >80 mg/dl had open-label ezetimibe 10mg added (E, n=33). Repeated measures models estimated changes in plaque parameters over time and between-group differences. RESULTS LDL-C was lower at year 1 in S+E (67 ± 7 mg/dl) than S (91 ± 8 mg/dl, p<0.05), but similar at year 2 (68 ± 10 mg/dl vs. 83 ± 11 mg/dl, respectively). Plaque volume did not change from baseline to year 2 in either S+E (11.5 ± 1.4-10.5 ± 1.3 cm(3), p=NS) or S (11.0 ± 1.5-10.5 ± 1.4 cm(3), p=NS). In E, plaque progressed from baseline to year 2 (10.0 ± 0.8-10.8 ± 0.9, p<0.01) despite a 22% decrease in LDL-C. CONCLUSIONS Statin initiation with or without ezetimibe in statin-naïve patients halts progression of peripheral atherosclerosis. When ezetimibe is added to patients previously on statins, peripheral atherosclerosis progressed. Thus, ezetimibe's effect on peripheral atherosclerosis may depend upon relative timing of statin therapy.
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Affiliation(s)
- Amy M. West
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Justin D. Anderson
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Craig H. Meyer
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, VA
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Frederick H. Epstein
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, VA
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Hongkun Wang
- Department of Public Health Sciences, University of Virginia Health System, University of Virginia, Charlottesville, VA
- Department of Biostatistics, Bioinformatics and Biomathematics, Georgetown University, Washington, DC
| | - Klaus D. Hagspiel
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, VA
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Stuart S. Berr
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, VA
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Nancy L. Harthun
- Department of Surgery and the Cardiovascular Imaging Center, University of Virginia Health System, University of Virginia, Charlottesville, VA
- Department of Surgery, Johns Hopkins University, Baltimore, MD
| | - Joseph M. DiMaria
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Jennifer R. Hunter
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - John M. Christopher
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Joshua D. Chew
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Gabriel B. Winberry
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, VA
| | - Christopher M. Kramer
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, VA
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, VA
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West AM, Anderson JD, Epstein FH, Meyer CH, Wang H, Hagspiel KD, Berr SS, Harthun NL, Weltman AL, DiMaria JM, Hunter JR, Christopher JM, Kramer CM. Low-density lipoprotein lowering does not improve calf muscle perfusion, energetics, or exercise performance in peripheral arterial disease. J Am Coll Cardiol 2011; 58:1068-76. [PMID: 21867844 PMCID: PMC3182461 DOI: 10.1016/j.jacc.2011.04.034] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Revised: 03/02/2011] [Accepted: 04/19/2011] [Indexed: 01/12/2023]
Abstract
OBJECTIVES We hypothesized that low-density lipoprotein (LDL) reduction regardless of mechanism would improve calf muscle perfusion, energetics, or walking performance in peripheral arterial disease (PAD) as measured by magnetic resonance imaging and magnetic resonance spectroscopy. BACKGROUND Statins improve cardiovascular outcome in PAD, and some studies suggest improved walking performance. METHODS Sixty-eight patients with mild to moderate symptomatic PAD (age 65 ± 11 years; ankle-brachial index [ABI] 0.69 ± 0.14) were studied at baseline and annually for 2 years after beginning simvastatin 40 mg (n = 20) or simvastatin 40 mg/ezetimibe 10 mg (n = 18) if statin naïve, or ezetimibe 10 mg (n = 30) if taking a statin. Phosphocreatine recovery time was measured by (31)P magnetic resonance spectroscopy immediately after symptom-limited calf exercise on a 1.5-T scanner. Calf perfusion was measured using first-pass contrast-enhanced magnetic resonance imaging with 0.1 mM/kg gadolinium at peak exercise. Gadolinium-enhanced magnetic resonance angiography was graded. A 6-min walk and a standardized graded Skinner-Gardner exercise treadmill test with peak Vo(2) were performed. A repeated-measures model compared changes over time. RESULTS LDL reduction from baseline to year 2 was greater in the simvastatin 40 mg/ezetimibe 10 mg group (116 ± 42 mg/dl to 56 ± 21 mg/dl) than in the simvastatin 40 mg group (129 ± 40 mg/dl to 90 ± 30 mg/dl, p < 0.01). LDL also decreased in the ezetimibe 10 mg group (102 ± 28 mg/dl to 79 ± 27 mg/dl, p < 0.01). Despite this, there was no difference in perfusion, metabolism, or exercise parameters between groups or over time. Resting ABI did improve over time in the ezetimibe 10 mg group and the entire study group of patients. CONCLUSIONS Despite effective LDL reduction in PAD, neither tissue perfusion, metabolism, nor exercise parameters improved, although rest ABI did. Thus, LDL lowering does not improve calf muscle physiology or functional capacity in PAD. (Comprehensive Magnetic Resonance of Peripheral Arterial Disease; NCT00587678).
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Affiliation(s)
- Amy M. West
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Justin D. Anderson
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Frederick H. Epstein
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Craig H. Meyer
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Hongkun Wang
- Department of Biostatistics, Bioinformatics, and Biomathematics, Georgetown University, Washington, DC
| | - Klaus D. Hagspiel
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Stuart S. Berr
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Nancy L. Harthun
- Department of Surgery, Johns Hopkins University, Baltimore, Maryland
| | - Arthur L. Weltman
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Joseph M. DiMaria
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Jennifer R. Hunter
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - John M. Christopher
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Christopher M. Kramer
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
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Beyers RJ, Smith RS, Xu Y, Piras BA, Salerno M, Berr SS, Meyer CH, Kramer CM, French BA, Epstein FH. T₂ -weighted MRI of post-infarct myocardial edema in mice. Magn Reson Med 2011; 67:201-9. [PMID: 21630350 DOI: 10.1002/mrm.22975] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 02/28/2011] [Accepted: 04/04/2011] [Indexed: 11/11/2022]
Abstract
T(2) -weighted, cardiac magnetic resonance imaging (T(2) w CMR) can be used to noninvasively detect and quantify the edematous region that corresponds to the area at risk (AAR) following myocardial infarction (MI). Previously, CMR has been used to examine structure and function in mice, expediting the study of genetic manipulations. To date, CMR has not been applied to imaging of post-MI AAR in mice. We developed a whole-heart, T(2) w CMR sequence to quantify the AAR in mouse models of ischemia and infarction. The ΔB(0) and ΔB(1) environment around the mouse heart at 7 T were measured, and a T(2) -preparation sequence suitable for these conditions was developed. Both in vivo T(2) w and late gadolinium enhanced CMR were performed in mice after 20-min coronary occlusions, resulting in measurements of AAR size of 32.5 ± 3.1 (mean ± SEM)% left ventricular mass, and MI size of 50.1 ± 6.4% AAR size. Excellent interobserver agreement and agreement with histology were also found. This T(2) w imaging method for mice may allow for future investigations of genetic manipulations and novel therapies affecting the AAR and salvaged myocardium following reperfused MI.
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Affiliation(s)
- Ronald J Beyers
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
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Zhang Y, Xiao L, Chordia MD, Locke LW, Williams MB, Berr SS, Pan D. Neutrophil Targeting Heterobivalent SPECT Imaging Probe: cFLFLF-PEG-TKPPR-99mTc. Bioconjug Chem 2010; 21:1788-93. [DOI: 10.1021/bc100063a] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yi Zhang
- Research Division of the Department of Radiology and Department of Chemistry, University of Virginia, Charlottesville, Virginia 22908
| | - Li Xiao
- Research Division of the Department of Radiology and Department of Chemistry, University of Virginia, Charlottesville, Virginia 22908
| | - Mahendra D. Chordia
- Research Division of the Department of Radiology and Department of Chemistry, University of Virginia, Charlottesville, Virginia 22908
| | - Landon W. Locke
- Research Division of the Department of Radiology and Department of Chemistry, University of Virginia, Charlottesville, Virginia 22908
| | - Mark B. Williams
- Research Division of the Department of Radiology and Department of Chemistry, University of Virginia, Charlottesville, Virginia 22908
| | - Stuart S. Berr
- Research Division of the Department of Radiology and Department of Chemistry, University of Virginia, Charlottesville, Virginia 22908
| | - Dongfeng Pan
- Research Division of the Department of Radiology and Department of Chemistry, University of Virginia, Charlottesville, Virginia 22908
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West AM, Anderson JD, Meyer CH, Epstein FH, Hagspiel KD, Berr SS, Harthun NL, DiMaria JM, Hunter JR, Christopher JM, Winberry GB, Van Opstal EJ, Chew JD, Kramer CM. Type of lipid lowering therapy impacts atherosclerosis progression in peripheral arterial disease as assessed by CMR. J Cardiovasc Magn Reson 2010. [DOI: 10.1186/1532-429x-12-s1-p130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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West AM, Anderson JD, Epstein FH, Meyer CH, Hagspiel KD, Wang H, Berr SS, Harthun NL, Weltman AL, DiMaria JM, Hunter JR, Christopher JM, Kramer CM. Diffferential effects of LDL Lowering on CMR measures of calf muscle perfusion and cellular metabolism in peripheral arterial disease. J Cardiovasc Magn Reson 2010. [DOI: 10.1186/1532-429x-12-s1-o93] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Anderson JD, Epstein FH, Meyer CH, Hagspiel KD, Wang H, Berr SS, Harthun NL, Weltman A, Dimaria JM, West AM, Kramer CM. Multifactorial determinants of functional capacity in peripheral arterial disease: uncoupling of calf muscle perfusion and metabolism. J Am Coll Cardiol 2009; 54:628-35. [PMID: 19660694 DOI: 10.1016/j.jacc.2009.01.080] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 01/06/2009] [Accepted: 01/14/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVES We aimed to investigate the pathophysiology of peripheral arterial disease (PAD) by examining magnetic resonance imaging (MRI) and spectroscopic (MRS) correlates of functional capacity. BACKGROUND Despite the high prevalence, morbidity, and cost of PAD, its pathophysiology is incompletely understood. METHODS Eighty-five patients (age 68 +/- 10 years) with mild-to-moderate PAD (ankle-brachial index 0.69 +/- 0.14) had their most symptomatic leg studied by MRI/MRS. Percent wall volume in the superficial femoral artery was measured with black blood MRI. First-pass contrast-enhanced MRI calf muscle perfusion and (31)P MRS phosphocreatine recovery time constant (PCr) were measured at peak exercise in calf muscle. All patients underwent magnetic resonance angiography (MRA), treadmill testing with maximal oxygen consumption measurement, and a 6-min walk test. RESULTS Mean MRA index of number and severity of stenoses was 0.84 +/- 0.68 (normal 0), % wall volume 74 +/- 11% (normal 46 +/- 7%), tissue perfusion 0.039 +/- 0.015 s(-1) (normal 0.065 +/- 0.013 s(-1)), and PCr 87 +/- 54 s (normal 34 +/- 16 s). MRA index, % wall volume, and ankle-brachial index correlated with most functional measures. PCr was the best correlate of treadmill exercise time, whereas calf muscle perfusion was the best correlate of 6-min walk distance. No correlation was noted between PCr and tissue perfusion. CONCLUSIONS Functional limitations in PAD are multifactorial. As measured by MRI and spectroscopy, atherosclerotic plaque burden, stenosis severity, tissue perfusion, and energetics all play a role. However, cellular metabolism is uncoupled from tissue perfusion. These findings suggest a potential role for therapies that regress plaque, increase tissue perfusion, and/or improve cellular metabolism. (Comprehensive Magnetic Resonance of Peripheral Arterial Disease; NCT00587678).
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Affiliation(s)
- Justin D Anderson
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, VA 22908, USA
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Keilholz SD, Bozlar U, Fujiwara N, Mata JF, Berr SS, Corot C, Hagspiel KD. MR diagnosis of a pulmonary embolism: comparison of P792 and Gd-DOTA for first-pass perfusion MRI and contrast-enhanced 3D MRA in a rabbit model. Korean J Radiol 2009; 10:447-54. [PMID: 19721829 PMCID: PMC2731862 DOI: 10.3348/kjr.2009.10.5.447] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Accepted: 02/12/2009] [Indexed: 11/16/2022] Open
Abstract
Objective To compare P792 (gadomelitol, a rapid clearance blood pool MR contrast agent) with gadolinium-tetraazacyclododecanetetraacetic acid (Gd-DOTA), a standard extracellular agent, for their suitability to diagnose a pulmonary embolism (PE) during a first-pass perfusion MRI and 3D contrast-enhanced (CE) MR angiography (MRA). Materials and Methods A perfusion MRI or CE-MRA was performed in a rabbit PE model following the intravenous injection of a single dose of contrast agent. The time course of the pulmonary vascular and parenchymal enhancement was assessed by measuring the signal in the aorta, pulmonary artery, and lung parenchyma as a function of time to determine whether there is a significant difference between the techniques. CE-MRA studies were evaluated by their ability to depict the pulmonary vasculature and following defects between 3 seconds and 15 minutes after a triple dose intravenous injection of the contrast agents. Results The P792 and Gd-DOTA were equivalent in their ability to demonstrate PE as perfusion defects on first pass imaging. The signal from P792 was significantly higher in vasculature than that from Gd-DOTA between the first and the tenth minutes after injection. The results suggest that a CE-MRA PE could be reliably diagnosed up to 15 minutes after injection. Conclusion P792 is superior to Gd-DOTA for the MR diagnosis of PE.
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Affiliation(s)
- Shella D Keilholz
- Department of Biomedical Engineering, Emory University, Atlanta, GA, USA
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Locke LW, Chordia MD, Zhang Y, Kundu B, Kennedy D, Landseadel J, Xiao L, Fairchild KD, Berr SS, Linden J, Pan D. A novel neutrophil-specific PET imaging agent: cFLFLFK-PEG-64Cu. J Nucl Med 2009; 50:790-7. [PMID: 19372473 DOI: 10.2967/jnumed.108.056127] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED The synthesis and validation of a new, highly potent (64)Cu-labeled peptide, cFLFLFK-PEG-(64)Cu, that targets the formyl peptide receptor (FPR) on leukocytes is described. The peptide ligand is an antagonist of the FPR, designed not to elicit a chemotactic response resulting in neutropenia. Evidence for the selective binding of this synthesized ligand to neutrophils is provided. PET properties of the compound were evaluated in a mouse model of lung inflammation. METHODS The FPR-specific peptide, cinnamoyl-F-(D)L-F-(D)L-FK (cFLFLF), was sequentially conjugated with a bifunctional polyethylene glycol moiety (PEG, 3.4 kD) and a 2,2',2'',2'''-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetraacetic acid (DOTA) through a lysine (K) spacer and finally labeled with (64)Cu-CuCl(2) to form cFLFLFK-PEG-(64)Cu. The binding affinity and stimulation potency of the ligand toward human neutrophils were assessed in vitro. Blood kinetic and organ biodistribution properties of the peptide were studied in the mouse. Ten male C57BL/6 mice were used in this study; 4 control mice and 6 administered Klebsiella pneumonia. PET/CT scans were performed to assess the localization properties of the labeled peptide in lungs 18 h after tracer administration. Lung standardized uptake values (SUVs) were correlated with lung neutrophil activity as measured by myeloperoxidase assays. Immunohistochemistry was performed to confirm that neutrophils constitute the majority of infiltrating leukocytes in lung tissue 24 h after Klebsiella exposure. RESULTS In vitro binding assays of the compound cFLFLFK-PEG-(64)Cu to the neutrophil FPR yielded a dissociation constant of 17.7 nM. The functional superoxide stimulation assay exhibited negligible agonist activity of the ligand with respect to neutrophil superoxide production. The pegylated peptide ligand exhibited a blood clearance half-life of 55 +/- 8 min. PET 18 h after tracer administration revealed mean lung SUVs and lung myeloperoxidase activities for Klebsiella-infected mice that were 5- and 6-fold higher, respectively, than those for control mice. Immunohistochemistry staining confirmed that the cellular infiltrate in lungs of Klebsiella-infected mice was almost exclusively neutrophils at the time of imaging. CONCLUSION This new radiolabeled peptide targeting the FPR binds to neutrophils in vitro and accumulates at sites of inflammation in vivo. This modified peptide may prove to be a useful tool to probe inflammation or injury.
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Affiliation(s)
- Landon W Locke
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
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West AM, Anderson JD, Meyer CD, Epstein FH, Hagspiel KD, Berr SS, Harthun NL, DiMaria JM, Hunter JR, Christopher JM, Winberry GB, Kramer CM. Initiation of statin therapy halts progression of atherosclerotic plaque burden in peripheral arterial disease. J Cardiovasc Magn Reson 2009. [PMCID: PMC7860780 DOI: 10.1186/1532-429x-11-s1-o19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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West AM, Anderson JD, Epstein FH, Meyer CH, Hagspiel KD, Berr SS, Harthun NL, Weltman AL, DiMaria JM, Hunter JR, Christopher JM, Kramer CM. Does lipid lowering therapy improve calf muscle perfusion and cellular metabolism in peripheral arterial disease? J Cardiovasc Magn Reson 2009. [PMCID: PMC7860684 DOI: 10.1186/1532-429x-11-s1-o61] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Yang Z, Linden J, Berr SS, Kron IL, Beller GA, French BA. Timing of adenosine 2A receptor stimulation relative to reperfusion has differential effects on infarct size and cardiac function as assessed in mice by MRI. Am J Physiol Heart Circ Physiol 2008; 295:H2328-35. [PMID: 18849340 DOI: 10.1152/ajpheart.00091.2008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The activation of adenosine 2A receptors before reperfusion following coronary artery occlusion reduces infarct size and improves ejection fraction (EF). In this study, we examined the effects of delaying treatment with the adenosine 2A receptor agonist ATL146e (ATL) until 1 h postreperfusion. The infarct size and EF were serially assessed by gadolinium-diethylenetriaminepentaacetic acid-enhanced MRI in C57BL/6 mice at 1 and 24 h postreperfusion. The infarct size was also assessed by 2,3,5-triphenyltetrazolium chloride staining at 24 h. Mice were treated with ATL (10 microg/kg ip) either 2 min before reperfusion (early ATL) or 1 h postreperfusion (late ATL) following the 45-min coronary occlusion. The two methods used to assess infarct size at 24 h postreperfusion (MRI and 2,3,5-triphenyltetrazolium chloride) showed an excellent correlation (R=0.96). The risk region, determined at 24 h postreperfusion, was comparable between the control and ATL-treated groups. The infarct size by MRI at 1 versus 24 h postreperfusion was 25+/-1 vs. 26+/-1% of left ventricular mass (means+/-SE) in control mice, 16+/-2 versus 17+/-2% in early-ATL mice, and 24+/-2 versus 25+/-2% in late-ATL mice (intragroup, P=not significant; and intergroup, early ATL vs. control or late ATL, P<0.05). EF was reduced in control mice but was largely preserved between 1 and 24 h in both early-ATL and late-ATL mice (P<0.05). In conclusion, after coronary occlusion in mice, the extent of myocellular death due to ischemia-reperfusion injury is 95% complete within 1 h of reperfusion. The infarct size was significantly reduced by ATL when given just before reperfusion, but not 1 h postreperfusion. Either treatment window helped preserve the EF between 1 and 24 h postreperfusion.
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Affiliation(s)
- Zequan Yang
- Department of Surgery, University of Virginia, MR5 Bldg. Rm. 1219, Box 800759, 415 Lane Rd., Charlottesville, VA 22903, USA
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Anderson JD, Epstein FH, Meyer CH, Hagspiel KD, Berr SS, Weltman AL, Wang H, Harthun NL, Norton PT, Isbell DC, Kramer CM. 1042 Multi-modality magnetic resonance demonstrates factors critical to functional capacity in peripheral arterial disease. J Cardiovasc Magn Reson 2008. [DOI: 10.1186/1532-429x-10-s1-a167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Isbell DC, Voros S, Yang Z, DiMaria JM, Berr SS, French BA, Epstein FH, Bishop SP, Wang H, Roy RJ, Kemp BA, Matsubara H, Carey RM, Kramer CM. Interaction between bradykinin subtype 2 and angiotensin II type 2 receptors during post-MI left ventricular remodeling. Am J Physiol Heart Circ Physiol 2007; 293:H3372-8. [DOI: 10.1152/ajpheart.00997.2007] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Angiotensin II type 2 receptor (AT2R) overexpression (AT2TG) attenuates left ventricular remodeling in a mouse model of anterior myocardial infarction (MI). We hypothesized that the beneficial effects of cardiac AT2TG are mediated via the bradykinin subtype 2 receptor (B2R). Fourteen transgenic mice overexpressing the AT2R (AT2TG mice), 10 mice with a B2R deletion (B2KO mice), 13 AT2TG mice with B2R deletion (AT2TG/B2KO mice), and 11 wild-type (WT) mice were studied. All mice were on a C57BL/6 background. Mice were studied by cardiac magnetic resonance imaging at baseline and days 1, 7, and 28 after MI induced by 1 h of occlusion of the left anterior descending artery followed by reperfusion. Short-axis images from apex to base were used to compare ventricular volumes and ejection fraction (EF). At baseline, end-diastolic volume index (EDVI) and end-systolic volume index (ESVI) were lower and EF higher in AT2TG mice compared with the other three strains. Infarct size was similar between groups. No differences were observed in global remodeling parameters at day 28 between AT2TG and AT2TG/B2KO mice; however, EDVI and ESVI were lower and EF higher in both transgenic groups than in WT or B2KO mice. Both strains lacking B2R demonstrated increased collagen content and less hypertrophy in adjacent noninfarcted regions at day 28. Attenuation of postinfarct remodeling by overexpression of AT2R is not directly mediated via a B2R pathway. However, B2R does appear to have a role in the smaller cavity size and hyperdynamic function observed at baseline in AT2TG mice and in limiting collagen deposition during postinfarct remodeling.
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Zhang Y, Kundu B, Fairchild KD, Locke L, Berr SS, Linden J, Pan D. Synthesis of novel neutrophil-specific imaging agents for Positron Emission Tomography (PET) imaging. Bioorg Med Chem Lett 2007; 17:6876-8. [PMID: 17959381 DOI: 10.1016/j.bmcl.2007.10.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Revised: 09/28/2007] [Accepted: 10/05/2007] [Indexed: 11/29/2022]
Abstract
A neutrophil-specific peptide, cinnamoyl-F(D)LF(D)LFK (cFLFLFK), was conjugated consecutively with a polyethylene glycol moiety (3.4K) and 2,2',2'',2'''-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetraacetic acid (DOTA) to form cFLFLFK-PEG-DOTA. After (64)Cu labeling, Positron Emission Tomography (PET) imaging was successfully able to detect mouse lung inflammation.
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Affiliation(s)
- Yi Zhang
- Department of Radiology, The University of Virginia, 409 Lane Road, MR4 Building 1192, PO Box 801339, Charlottesville, VA 22908, USA
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Isbell DC, Epstein FH, Zhong X, DiMaria JM, Berr SS, Meyer CH, Rogers WJ, Harthun NL, Hagspiel KD, Weltman A, Kramer CM. Calf muscle perfusion at peak exercise in peripheral arterial disease: measurement by first-pass contrast-enhanced magnetic resonance imaging. J Magn Reson Imaging 2007; 25:1013-20. [PMID: 17410566 PMCID: PMC2930771 DOI: 10.1002/jmri.20899] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To develop a contrast-enhanced magnetic resonance (MR) technique to measure skeletal muscle perfusion in peripheral arterial disease (PAD). MATERIALS AND METHODS A total of 11 patients (age = 61 +/- 11 years) with mild to moderate symptomatic PAD (ankle-brachial index [ABI] = 0.75 +/- 0.08) and 22 normals were studied using an MR-compatible ergometer. PAD and normal(max) (Nl(max); N = 11) exercised to exhaustion. Nl(low) (N = 11) exercised to the same workload achieved by PAD. At peak exercise, 0.1 mm/kg of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) was infused at 3-4 cm(3)/second followed by a saline flush at the same rate. A dual-contrast gradient echo (GRE) sequence enabled simultaneous acquisition of muscle perfusion and arterial input function (AIF). The perfusion index (PI) was defined as the slope of the time-intensity curve (TIC) in muscle divided by the arterial TIC slope. RESULTS Median workload was 120 Joules in PAD, 210 Joules in Nl(low), and 698 Joules in Nl(max) (P < 0.001 vs. Nl(low) and PAD). Median PI was 0.29 in PAD (25th and 75th percentiles [%] = 0.20, 0.40), 0.48 in Nl(low) (25th, 75th % = 0.36, 0.62; P < 0.02 vs. PAD), and 0.69 in Nl(max) (25th, 75th % = 0.5, 0.77; P < 0.001 vs. PAD). Area under the ROC-curve for PI differentiating patients from Nl(max) was 0.95 (95% confidence interval [CI] = 0.77-0.99). CONCLUSION Peak-exercise measurement of lower limb perfusion with dual-contrast, first-pass MR distinguishes PAD from normals. This method may be useful in the study of novel therapies for PAD.
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Affiliation(s)
- David C. Isbell
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
| | - Frederick H. Epstein
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
| | | | - Joseph M. DiMaria
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
| | - Stuart S. Berr
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
| | - Craig H. Meyer
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
| | - Walter J. Rogers
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
| | - Nancy L. Harthun
- Department of Surgery, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
| | - Klaus D. Hagspiel
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
| | - Arthur Weltman
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
| | - Christopher M. Kramer
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia, USA
- Address reprint requests to: C.M.K., MD, University of Virginia Health System, Departments of Medicine and Radiology, Lee Street, Box 800170, Charlottesville, VA 22908.
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Berr SS, Xu Y, Roy RJ, Kundu B, Williams MB, French BA. Images in cardiovascular medicine. Serial multimodality assessment of myocardial infarction in mice using magnetic resonance imaging and micro-positron emission tomography provides complementary information on the progression of scar formation. Circulation 2007; 115:e428-9. [PMID: 17470701 DOI: 10.1161/circulationaha.106.673749] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Stuart S Berr
- Department of Radiology, University of Virginia, Health System, Charlottesville, VA 22908, USA.
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Prasad KMR, Xu Y, Yang Z, Toufektsian MC, Berr SS, French BA. Topoisomerase Inhibition Accelerates Gene Expression after Adeno-associated Virus-mediated Gene Transfer to the Mammalian Heart. Mol Ther 2007; 15:764-771. [PMID: 28192703 DOI: 10.1038/sj.mt.6300071] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Accepted: 10/26/2006] [Indexed: 01/29/2023] Open
Abstract
Utility of adeno-associated virus 2 (AAV2) vectors for cardiac gene therapy is limited by the prolonged lag phase before maximal gene expression. Topoisomerase inhibition can induce AAV2-mediated gene expression in vivo, but with variable success in different tissues. In this study, we demonstrate that topoisomerase inhibition can accelerate AAV2-mediated gene expression in the mouse heart. We used an AAV2 vector expressing firefly luciferase and monitored expression kinetics using non-invasive bioluminescence imaging. In the group receiving vector alone, cardiac luciferase activity was evident from week 2 onward and increased progressively to reach a steady plateau by 9 weeks postinjection. In the group receiving vector and camptothecine (CPT), luciferase expression was evident from days 2 to 4 onward and increased rapidly to reach a steady plateau by 3-4 weeks postinjection, nearly three times faster than in the absence of CPT (P<0.05). Southern blot analysis of AAV2 genomes in cardiac tissue showed rapid conversion of the AAV2 genome from its single-stranded to double-stranded form in CPT-treated mice. Non-invasive determinations of luciferase expression correlated well with in vitro luciferase assays. Direct injection of the AAV2 vector and long-term luciferase gene expression had no detectable effects on normal cardiac function as assessed by magnetic resonance imaging.
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Affiliation(s)
- Konkal-Matt R Prasad
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Yaqin Xu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Zequan Yang
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | | | - Stuart S Berr
- Department of Radiology, University of Virginia, Charlottesville, Virginia, USA
| | - Brent A French
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA; Department of Radiology, University of Virginia, Charlottesville, Virginia, USA.
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Young AA, French BA, Yang Z, Cowan BR, Gilson WD, Berr SS, Kramer CM, Epstein FH. Reperfused myocardial infarction in mice: 3D mapping of late gadolinium enhancement and strain. J Cardiovasc Magn Reson 2007; 8:685-92. [PMID: 16891227 DOI: 10.1080/10976640600721767] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
We developed mathematical modeling tools for mapping 3D infarct geometry from multislice late gadolinium enhancement data, allowing fusion with multislice MR tagging data, in mice with myocardial infarction. Five C57BL/6 mice were imaged at baseline, 1, 7 and 28 days after 60 min occlusion of the left anterior descending coronary artery. The 3D infarct geometry was mapped in material coordinates, and registered with 3D strain, showing permanent dysfunction in infarcted segments, intermediate function in the adjacent zone, and maintained function in the remote zone. 3D mapping of late enhancement and strain allows registration of multiple studies in a consistent framework.
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Affiliation(s)
- Alistair A Young
- Department of Anatomy with Radiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
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Wu Y, McRoberts K, Berr SS, Frierson HF, Conaway M, Theodorescu D. Neuromedin U is regulated by the metastasis suppressor RhoGDI2 and is a novel promoter of tumor formation, lung metastasis and cancer cachexia. Oncogene 2006; 26:765-73. [PMID: 16878152 DOI: 10.1038/sj.onc.1209835] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Most deaths from urinary bladder cancer are owing to metastatic disease. A reduction in Rho GDP Dissociation Inhibitor 2 (RhoGDI2) protein has been associated with increased risk of metastasis in patients with locally advanced bladder cancer, whereas in animal models, RhoGDI2 reconstitution in cells without expression results in lung metastasis suppression. Recently, we noted an inverse correlation between tumor RhoGDI2 and Neuromedin U (NMU) expression, suggesting that NMU might be a target of the lung metastasis suppressor effect of RhoGDI2. Here we evaluated whether NMU is regulated by RhoGDI2 and is functionally important in tumor progression. We used small interfering RNA knockdown of endogenous RhoGDI2 in poorly tumorigenic and non-metastatic human bladder cancer T24 cells and observed increased NMU RNA expression. Although NMU overexpression did not increase the monolayer growth of T24 or related T24T poorly metastatic human bladder cancer cells, it did augment anchorage-independent growth for the latter. Overexpression of NMU in T24 and T24T cells significantly promoted tumor formation of both cell lines in nude mice, but did not alter the growth rate of established tumors. Furthermore, NMU-overexpressing xenografts were associated with lower animal body weight than control tumors, indicating a possible role of NMU in cancer cachexia. NMU overexpression in T24T cells significantly enhanced their lung metastatic ability. Bioluminescent in vivo imaging revealed that lung metastases in T24T grew faster than the same tumors in the subcutaneous microenvironment. In conclusion, NMU is a RhoGDI2-regulated gene that appears important for tumorigenicity, lung metastasis and cancer cachexia, and thus a promising therapeutic target in cancer.
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Affiliation(s)
- Y Wu
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, USA
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43
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Isbell DC, Berr SS, Toledano AY, Epstein FH, Meyer CH, Rogers WJ, Harthun NL, Hagspiel KD, Weltman A, Kramer CM. Delayed calf muscle phosphocreatine recovery after exercise identifies peripheral arterial disease. J Am Coll Cardiol 2006; 47:2289-95. [PMID: 16750698 PMCID: PMC2933934 DOI: 10.1016/j.jacc.2005.12.069] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2005] [Revised: 12/20/2005] [Accepted: 12/30/2005] [Indexed: 12/01/2022]
Abstract
OBJECTIVES In this study we intend to characterize phosphocreatine (PCr) recovery kinetics with phosphorus-31 ((31)P) magnetic resonance spectroscopy in symptomatic peripheral arterial disease (PAD) patients compared with control subjects and determine the diagnostic value and reproducibility of this parameter. BACKGROUND Due to the inconsistent relationship between flow and function in PAD, novel techniques focused on the end-organ are needed to assess disease severity and measure therapeutic response. METHODS Fourteen normal subjects (5 men, age 45 +/- 14 years) and 20 patients with mild-to-moderate symptomatic PAD (12 men, age 67 +/- 10 years, mean ankle brachial index 0.62 +/- 0.13) were studied. Subjects exercised one leg to exhaustion while supine in a 1.5-T magnetic resonance scanner using a custom-built plantar flexion device. Surface coil-localized, free induction decay acquisition localized to the mid-calf was used. Each 31P spectrum consisted of 25 signal averages at a repetition time of 550 ms. The PCr recovery time constant was calculated by monoexponential fit of PCr versus time, beginning at exercise completion. RESULTS Median exercise time was 195.0 s in normal subjects and 162.5 s in PAD patients (p = 0.06). Despite shorter exercise times in patients, the median recovery time constant of PCr was 34.7 s in normal subjects and 91.0 s in PAD patients. Area under the receiver-operating characteristic curve was 0.925 +/- 0.045. Test-retest reliability was excellent. CONCLUSIONS The PCr recovery time constant is prolonged in patients with symptomatic PAD compared with normal subjects. The method is reproducible and may be useful in the identification of disease. Further study of this parameter's ability to track response to therapy as well as its prognostic capability is warranted.
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Affiliation(s)
- David C. Isbell
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Stuart S. Berr
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Alicia Y. Toledano
- Department of Surgery, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Frederick H. Epstein
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Craig H. Meyer
- Department of Biomedical Engineering, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Walter J. Rogers
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Nancy L. Harthun
- Center for Statistical Sciences, Brown University, Providence, Rhode Island
| | - Klaus D. Hagspiel
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Arthur Weltman
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
| | - Christopher M. Kramer
- Department of Medicine, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
- Department of Radiology, University of Virginia Health System, University of Virginia, Charlottesville, Virginia
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Voros S, Yang Z, Bove CM, Gilson WD, Epstein FH, French BA, Berr SS, Bishop SP, Conaway MR, Matsubara H, Carey RM, Kramer CM. Interaction between AT1 and AT2 receptors during postinfarction left ventricular remodeling. Am J Physiol Heart Circ Physiol 2006; 290:H1004-10. [PMID: 16214839 DOI: 10.1152/ajpheart.00886.2005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The relative contribution of the angiotensin II type 1 and 2 receptors (AT1-R and AT2-R) in postmyocardial infarction (MI) remodeling remains incompletely understood. We studied five groups of C57Bl/6 mice after 1 h of left anterior descending artery occlusion-reperfusion: 1) wild type, untreated ( n = 12); 2) wild type, treated with the AT1-R blocker losartan (10–20 mg·kg−1·day−1 in drinking water) from day 1 to day 28 post-MI ( n = 10); 3) cardiac overexpression of the AT2-R [AT2-transgenic (TG); n = 14]; 4) AT2-TG treated with losartan ( n = 13); and 5) AT2-TG and null for the AT1a-R [AT2-TG/AT1 knockout (KO); n = 10]. Cardiac magnetic resonance imaging (CMR) measured ejection fraction and left ventricular end-diastolic and end-systolic volume (EDVI and ESVI) and mass indexed to weight on days 0, 1, 7, and 28 post-MI. Infarct size was measured on day 1 by late gadolinium-enhanced CMR. Regional myocyte hypertrophy and collagen content were measured on day 28 post-MI. Infarct size was similar among groups. Systolic blood pressure was lowest in AT2-TG/AT1KO. By day 28 post-MI, when corrected for baseline differences, EDVI and ESVI were higher and ejection fraction was lower in wild type than other groups. Ejection fraction was highest and EDVI and mass index were lowest in AT2-TG/AT1KO at day 28. The AT2-TG/AT1KO demonstrated less fibrosis in adjacent regions. Regional myocyte hypertrophy was similar in all groups. The AT1-R and AT2-R are intricately intertwined in post-MI remodeling. Pharmacological blockade of AT1-R is equivalent to AT2-R overexpression in attenuating post-MI remodeling. Genetic knockout of the AT1a-R is additive to AT2-R overexpression, due, at least in part, to blood pressure lowering.
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Affiliation(s)
- Szilard Voros
- Department of Medicine, University of Virginia Health System, Lee St., Box 800170, Charlottesville, Virginia 22908, USA
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Berr SS, Roy RJ, French BA, Yang Z, Gilson W, Kramer CM, Epstein FH. Black blood gradient echo cine magnetic resonance imaging of the mouse heart. Magn Reson Med 2005; 53:1074-9. [PMID: 15844138 DOI: 10.1002/mrm.20487] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A black blood gradient echo sequence for multiphase cardiac MRI of the mouse heart was implemented on a 4.7-T scanner and compared to a conventional bright blood sequence. Black blood was achieved using the double inversion recovery technique. Ten mice were imaged using both the bright and the black blood sequences, and 2 of the mice were additionally imaged using bright and black blood sequences modified to perform myocardial tagging. Manual planimetry of the images was performed by two independent observers to detect the endocardial and epicardial borders and subsequently to compute chamber volumes and myocardial mass. Weight of the excised left ventricle was used as a gold standard for myocardial mass. Bland-Altman analysis demonstrated reduced interobserver variability for the measurement of cardiac volumes using the black blood sequence compared to the bright blood sequence (95% confidence interval was -0.89-0.73 microL for black blood versus -1.86-1.28 microL for bright blood). Also, Bland-Altman analysis showed that the black blood sequence provides improved accuracy for the measurement of myocardial mass compared to the bright blood sequence (average difference between MRI versus weight was 0.9 microg for black blood and -11.2 microg for bright blood, P < 0.01). For myocardial tagging, qualitative assessment demonstrated improved endocardial border definition using the black blood sequence. Black blood cine MRI in mice provides reduced interobserver variability and improved accuracy for the measurement of myocardial volumes and mass compared to the conventional bright blood technique.
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Affiliation(s)
- Stuart S Berr
- Department of Radiology, University of Virginia, Charlottesville, USA
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46
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Bove CM, Gilson WD, Scott CD, Epstein FH, Yang Z, Dimaria JM, Berr SS, French BA, Bishop SP, Kramer CM. The angiotensin II type 2 receptor and improved adjacent region function post-MI. J Cardiovasc Magn Reson 2005; 7:459-64. [PMID: 15881529 DOI: 10.1081/jcmr-200053461] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Angiotensin II type 2 receptor (AT2-R) overexpression in the mouse heart preserves left ventricular (LV) size and global LV function during post-MI remodeling. We hypothesized that CMR tagging would localize regional improvements in myocardial function during post-MI remodeling in AT2-R cardiac overexpressed transgenic mice (TG), which could explain the preservation of global LV function post-MI. Six male wild-type (WT) C57BL/6 mice and 10 TG mice were studied by CMR at baseline (day 0) and days 1, 7, and 28 post-MI. MI was induced by 1 hour occlusion of the LAD followed by reperfusion. On day 1 post-MI, gadolinium-DTPA was injected to assess infarct size. LV size and function was assessed by cine CMR. Mean % circumferential shortening (%CS) was calculated within infarcted, adjacent, and remote regions at each time point in WT and TG mice. Quantitative interstitial collagen and mean myocyte cross-sectional area was measured postmortem at day 28 post-MI. LV end-systolic volume was lower and ejection fraction higher at baseline in the TG group and these differences were maintained post-MI. Within infarcted and remote zones, although %CS was higher in TG mice at day 0, there was no difference by day 28 between groups. Within adjacent regions, while there was no difference at day 0 or 1 in TG vs. WT, %CS was significantly higher in TG mice by day 7, and these changes persisted out to day 28 post-MI. Regional interstitial collagen and myocyte size were similar between groups. Thus, myocardial tagging can detect regional differences in contractile function post-MI in TG mice, and AT2-R overexpression is associated with improved contractile function in adjacent noninfarcted myocardium.
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MESH Headings
- Angiotensin II/physiology
- Animals
- Collagen/analysis
- Contrast Media
- Disease Models, Animal
- Gadolinium DTPA
- Heart Ventricles/pathology
- Image Processing, Computer-Assisted
- Magnetic Resonance Imaging, Cine
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Myocardial Contraction/physiology
- Myocardial Infarction/pathology
- Myocardial Infarction/physiopathology
- Myocytes, Cardiac/pathology
- Receptor, Angiotensin, Type 2/physiology
- Stroke Volume/physiology
- Systole/physiology
- Ventricular Dysfunction, Left/pathology
- Ventricular Dysfunction, Left/physiopathology
- Ventricular Remodeling/physiology
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Affiliation(s)
- Christina M Bove
- Department of Medicine, University of Virginia Health System, Charlottesville, Virginia, USA
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Abstract
PURPOSE We develop a realistic and flexible 4-D digital mouse phantom and investigate its usefulness in molecular imaging research. METHODS Organ shapes were modeled with non-uniform rational B-spline (NURBS) surfaces based on high-resolution 3-D magnetic resonance microscopy (MRM) data. Cardiac and respiratory motions were modeled based on gated magnetic resonance imaging (MRI) data obtained from normal mice. Pilot simulation studies in single-photon emission computed tomography (SPECT) and X-ray computed tomography (CT) were performed to demonstrate the utility of the phantom. RESULTS NURBS are an efficient and flexible way to accurately model the anatomy and cardiac and respiratory motions for a realistic 4-D digital mouse phantom. The phantom is capable of producing realistic molecular imaging data from which imaging devices and techniques can be evaluated. CONCLUSION The phantom provides a unique and useful tool in molecular imaging research. It can be used in the development of new imaging instrumentation, image acquisition strategies, and image processing and reconstruction methods.
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Affiliation(s)
- William P Segars
- Department of Radiology, Johns Hopkins University, Baltimore, MD, USA.
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48
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Hagspiel KD, Leung DA, Nandalur KR, Angle JF, Dulai HS, Spinosa DJ, Matsumoto AH, Christopher JM, Ahmed H, Berr SS. Contrast-Enhanced MR Angiography at 1.5 T After Implantation of Platinum Stents: In Vitro and In Vivo Comparison with Conventional Stent Designs. AJR Am J Roentgenol 2005; 184:288-94. [PMID: 15615990 DOI: 10.2214/ajr.184.1.01840288] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The objective of our study was to evaluate the in vitro and in vivo 3D contrast-enhanced MR angiography characteristics of a new platinum-based balloon-expandable stent system and compare this system with a variety of competing metallic stents. MATERIALS AND METHODS All experiments were performed on 1.5-T scanners. In vitro experiments were performed using 10 stents implanted into a custom-built phantom. Different orientations of the stents along the magnetic field and multiple flip angles were examined. In addition, 19 patients underwent contrast-enhanced MR angiography after the implantation of 36 stents, including four patients with six platinum stents. Angiographic correlation was available for all 19 patients, and luminal patency and stent-induced artifacts were assessed quantitatively. RESULTS Of the tested balloon-expandable stents, only the platinum-based stents created artifact causing luminal narrowing of 30% or less. All other balloon-expandable stents induced larger artifacts that resulted in higher degrees of narrowing. Thus, if patent, the platinum-based stents allow significant in-stent stenosis to be ruled out reliably. Selected nitinol- or tantalum-based self-expandable stents also are suitable in this regard. CONCLUSION Of the tested devices, platinum-based stents are the only type of currently available balloon-expandable stent that creates 30% or less artifact-induced apparent stenosis and thus are suitable for MR angiography.
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Affiliation(s)
- Klaus D Hagspiel
- Department of Radiology, Division of Interventional Radiology, University of Virginia Health System, Box 800170, Charlottesville, VA 22908, USA
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Jia LG, Donnet C, Bogaev RC, Blatt RJ, McKinney CE, Day KH, Berr SS, Jones LR, Moorman JR, Sweadner KJ, Tucker AL. Hypertrophy, increased ejection fraction, and reduced Na-K-ATPase activity in phospholemman-deficient mice. Am J Physiol Heart Circ Physiol 2004; 288:H1982-8. [PMID: 15563542 DOI: 10.1152/ajpheart.00142.2004] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phospholemman (FXYD1), a 72-amino acid transmembrane protein abundantly expressed in the heart and skeletal muscle, is a major substrate for phosphorylation in the cardiomyocyte sarcolemma. Biochemical, cellular, and electrophysiological studies have suggested a number of possible roles for this protein, including ion channel modulator, taurine-release channel, Na(+)/Ca(2+) exchanger modulator, and Na-K-ATPase-associated subunit. We have generated a phospholemman-deficient mouse. The adult null mice exhibited increased cardiac mass, larger cardiomyocytes, and ejection fractions that were 9% higher by magnetic resonance imaging compared with wild-type animals. Notably, this occurred in the absence of hypertension. Total Na-K-ATPase activity was 50% lower in the phospholemman-deficient hearts. Expression (per unit of membrane protein) of total Na-K-ATPase was only slightly diminished, but expression of the minor alpha(2)-isoform, which has been specifically implicated in the control of contractility, was reduced by 60%. The absence of phospholemman thus results in a complex response, including a surprisingly large reduction in intrinsic Na-K-ATPase activity, changes in Na-K-ATPase isoform expression, increase in ejection fraction, and increase in cardiac mass. We hypothesize that a primary effect of phospholemman is to modulate the Na-K-ATPase and that its reduced activity initiates compensatory responses.
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Affiliation(s)
- Li-Guo Jia
- Dividsion of Cardiovascular Medicine, Box 801394 MR5, University of Virginia Health System, Charlottesville, VA 22908, USA
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50
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Bove CM, Yang Z, Gilson WD, Epstein FH, French BA, Berr SS, Bishop SP, Matsubara H, Carey RM, Kramer CM. Nitric Oxide Mediates Benefits of Angiotensin II Type 2 Receptor Overexpression During Post-Infarct Remodeling. Hypertension 2004; 43:680-5. [PMID: 14732725 DOI: 10.1161/01.hyp.0000115924.94236.91] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We hypothesized that nitric oxide (NO) mediates the benefits of cardiac angiotensin II type 2 (AT(2)-R) overexpression during postmyocardial infarction (post-MI) remodeling. Eleven wild-type (WT) C57BL/6 mice and 28 transgenic (TG) mice with AT(2)-R overexpression were studied by cardiac magnetic resonance imaging (CMR) at baseline and days 1 and 28 post-MI induced by left anterior descending artery occlusion and reperfusion. Sixteen TG mice were treated from day 1 through 28 post-MI with the NO synthase inhibitor N(G)-nitro-l-arginine methyl ester in drinking water at 1 mg/mL (TG-Rx). Left ventricular mass index (LVMI), end-diastolic volume index (EDVI) and end-systolic volume index (ESVI), wall thickness, percent thickening, and ejection fraction (EF) were measured. Infarct size on day 1 was assessed by post-contrast CMR. Interstitial collagen was quantified in noninfarcted regions. At baseline, heart rate (HR), blood pressure (BP), LVMI, EDVI, and ESVI were similar between groups, as were infarct size and weekly post-MI HR and systolic BP. By day 28 post-MI, EDVI and ESVI were similar in WT and TG-Rx, but significantly lower in TG (ESVI: 1.41+/-0.18 microL/g versus 2.53+/-0.14 microL/g in WT; 2.17+/-0.14 microL/g in TG-Rx; P<0.008 for both). At day 28, EF was higher in TG (46.3%+/-2.9%) compared with WT and TG-Rx (32.7+/-2.3% and 33.7+/-2.3, respectively; P<0.003 for both). Wall thickening at day 28 post-MI was greater in the base and mid-LV in TG than WT and TG-Rx. Noninfarcted region interstitial collagen was similar between groups. Thus, the NO pathway may mediate much of the benefits of cardiac AT(2)-R overexpression during post-MI remodeling.
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Affiliation(s)
- Christina M Bove
- University of Virginia Health System, Departments of Medicine and Radiology, Lee Street, Box 800170, Charlottesville, VA 22908, USA.
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