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Matsumoto KI, Mitchell JB, Krishna MC. Multimodal Functional Imaging for Cancer/Tumor Microenvironments Based on MRI, EPRI, and PET. Molecules 2021; 26:1614. [PMID: 33799481 PMCID: PMC8002164 DOI: 10.3390/molecules26061614] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/09/2021] [Accepted: 03/11/2021] [Indexed: 11/23/2022] Open
Abstract
Radiation therapy is one of the main modalities to treat cancer/tumor. The response to radiation therapy, however, can be influenced by physiological and/or pathological conditions in the target tissues, especially by the low partial oxygen pressure and altered redox status in cancer/tumor tissues. Visualizing such cancer/tumor patho-physiological microenvironment would be a useful not only for planning radiotherapy but also to detect cancer/tumor in an earlier stage. Tumor hypoxia could be sensed by positron emission tomography (PET), electron paramagnetic resonance (EPR) oxygen mapping, and in vivo dynamic nuclear polarization (DNP) MRI. Tissue oxygenation could be visualized on a real-time basis by blood oxygen level dependent (BOLD) and/or tissue oxygen level dependent (TOLD) MRI signal. EPR imaging (EPRI) and/or T1-weighted MRI techniques can visualize tissue redox status non-invasively based on paramagnetic and diamagnetic conversions of nitroxyl radical contrast agent. 13C-DNP MRI can visualize glycometabolism of tumor/cancer tissues. Accurate co-registration of those multimodal images could make mechanisms of drug and/or relation of resulted biological effects clear. A multimodal instrument, such as PET-MRI, may have another possibility to link multiple functions. Functional imaging techniques individually developed to date have been converged on the concept of theranostics.
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Affiliation(s)
- Ken-ichiro Matsumoto
- Quantitative RedOx Sensing Group, Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Quantum Medical Science Directorate, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - James B. Mitchell
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1002, USA;
| | - Murali C. Krishna
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1002, USA;
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Bagga P, Hariharan H, Wilson NE, Beer JC, Shinohara RT, Elliott MA, Baur JA, Marincola FM, Witschey WR, Haris M, Detre JA, Reddy R. Single-Voxel 1 H MR spectroscopy of cerebral nicotinamide adenine dinucleotide (NAD + ) in humans at 7T using a 32-channel volume coil. Magn Reson Med 2019; 83:806-814. [PMID: 31502710 DOI: 10.1002/mrm.27971] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/15/2019] [Accepted: 08/06/2019] [Indexed: 12/12/2022]
Abstract
PURPOSE Reliable monitoring of tissue nicotinamide adenine dinucleotide (NAD+ ) concentration may provide insights on its roles in normal and pathological aging. In the present study, we report a 1 H MRS pulse sequence for the in vivo, localized 1 H MRS detection of NAD+ from the human brain. METHODS Studies were carried out on a 7T Siemens MRI scanner using a 32-channel product volume coil. The pulse sequence consisted of a spectrally selective low bandwidth E-BURP-1 90° pulse. PRESS localization was achieved using optimized Shinnar-Le Roux 180° pulses and overlapping gradients were used to minimize the TE. The reproducibility of NAD+ quantification was measured in 11 healthy volunteers. The association of cerebral NAD+ with age was assessed in 16 healthy subjects 26-78 years old. RESULTS Spectra acquired from a voxel placed in subjects' occipital lobe consisted of downfield peaks from the H2 , H4 , and H6 protons of the nicotinamide moiety of NAD+ between 8.9-9.35 ppm. The mean ± SD within-session and between-session coefficients of variation were found to be 6.14 ± 2.03% and 6.09 ± 3.20%, respectively. In healthy volunteers, an age-dependent decline of the NAD+ levels in the brain was also observed (β = -1.24 μM/y, SE = 0.21, P < 0.001). CONCLUSION We demonstrated the feasibility and robustness of a newly developed 1 H MRS technique to measure localized cerebral NAD+ at 7T MRI using a commercially available RF head coil. This technique may be further applied to detect and quantify NAD+ from different regions of the brain as well as from other tissues.
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Affiliation(s)
- Puneet Bagga
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Hari Hariharan
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Neil E Wilson
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Joanne C Beer
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Russell T Shinohara
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, Pennsylvania.,Center for Biomedical Image Computing and Analytics, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Mark A Elliott
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Joseph A Baur
- Department of Physiology and Institute of Diabetes, Obesity and Metabolism, University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Walter R Witschey
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Mohammad Haris
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.,Research Branch, Sidra Medical and Research Center, Doha, Qatar.,Laboratory Animal Research Center, Qatar University, Doha, Qatar
| | - John A Detre
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ravinder Reddy
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
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Yang H, Zhang Y, Chen S, Hao R. Micro-optical Components for Bioimaging on Tissues, Cells and Subcellular Structures. MICROMACHINES 2019; 10:E405. [PMID: 31248115 PMCID: PMC6630880 DOI: 10.3390/mi10060405] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 05/27/2019] [Accepted: 06/14/2019] [Indexed: 12/26/2022]
Abstract
Bioimaging generally indicates imaging techniques that acquire biological information from living forms. Among different imaging techniques, optical microscopy plays a predominant role in observing tissues, cells and biomolecules. Along with the fast development of microtechnology, developing miniaturized and integrated optical imaging systems has become essential to provide new imaging solutions for point-of-care applications. In this review, we will introduce the basic micro-optical components and their fabrication technologies first, and further emphasize the development of integrated optical systems for in vitro and in vivo bioimaging, respectively. We will conclude by giving our perspectives on micro-optical components for bioimaging applications in the near future.
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Affiliation(s)
- Hui Yang
- Laboratory of Biomedical Microsystems and Nano Devices, Bionic Sensing and Intelligence Center, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
| | - Yi Zhang
- Institute of Biomedical Therapeutics, University of Southern California, Los Angeles, CA 90033, USA.
| | - Sihui Chen
- Laboratory of Biomedical Microsystems and Nano Devices, Bionic Sensing and Intelligence Center, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
| | - Rui Hao
- Laboratory of Biomedical Microsystems and Nano Devices, Bionic Sensing and Intelligence Center, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
- Pen-Tung Sah Institute of Micro-Nano Science and Technology, Xiamen University, Xiamen 361005, China.
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Weber-Fahr W, Englisch S, Esser A, Tunc-Skarka N, Meyer-Lindenberg A, Ende G, Zink M. Altered phospholipid metabolism in schizophrenia: a phosphorus 31 nuclear magnetic resonance spectroscopy study. Psychiatry Res 2013; 214:365-73. [PMID: 24045051 DOI: 10.1016/j.pscychresns.2013.06.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 05/31/2013] [Accepted: 06/21/2013] [Indexed: 12/26/2022]
Abstract
Phospholipid (PL) metabolism is investigated by in vivo 31P magnetic resonance spectroscopy (MRS). Inconsistent alterations of phosphocholine (PC), phosphoethanolamine (PE), glycerophosphocholine (GPC) and glycerophosphoethanolamine (GPE) have been described in schizophrenia, which might be overcome by specific editing techniques. The selective refocused insensitive nuclei-enhanced polarization transfer (RINEPT) technique was applied in a cross-sectional study involving 11 schizophrenia spectrum disorder patients (SZP) on stable antipsychotic monotherapy and 15 matched control subjects. Metabolite signals were found to be modulated by cerebrospinal fluid (CSF) content and gray matter/brain matter ratio. Corrected metabolite concentrations of PC, GPC and PE differed between patients and controls in both subcortical and cortical regions, whereas antipsychotic medication exerted only small effects. Significant correlations were found between the severity of clinical symptoms and the assessed signals. In particular, psychotic symptoms correlated with PC levels in the cerebral cortex, depression with PC levels in the cerebellum and executive functioning with GPC in the insular and temporal cortices. In conclusion, after controlling for age and tissue composition, this investigation revealed alterations of metabolite levels in SZP and correlations with clinical properties. RINEPT 31P MRS should also be applied to at-risk-mental-state patients as well as drug-naïve and chronically treated schizophrenic patients in order to enhance the understanding of longitudinal alterations of PL metabolism in schizophrenia.
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Affiliation(s)
- Wolfgang Weber-Fahr
- Department of Neuroimaging, Central Institute of Mental Health, University of Heidelberg, Mannheim, Germany
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Bokacheva L, Ackerstaff E, LeKaye HC, Zakian K, Koutcher JA. High-field small animal magnetic resonance oncology studies. Phys Med Biol 2013; 59:R65-R127. [PMID: 24374985 DOI: 10.1088/0031-9155/59/2/r65] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This review focuses on the applications of high magnetic field magnetic resonance imaging (MRI) and spectroscopy (MRS) to cancer studies in small animals. High-field MRI can provide information about tumor physiology, the microenvironment, metabolism, vascularity and cellularity. Such studies are invaluable for understanding tumor growth and proliferation, response to treatment and drug development. The MR techniques reviewed here include (1)H, (31)P, chemical exchange saturation transfer imaging and hyperpolarized (13)C MRS as well as diffusion-weighted, blood oxygen level dependent contrast imaging and dynamic contrast-enhanced MRI. These methods have been proven effective in animal studies and are highly relevant to human clinical studies.
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Affiliation(s)
- Louisa Bokacheva
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 415 East 68 Street, New York, NY 10065, USA
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Scott WE, Weegman BP, Ferrer-Fabrega J, Stein SA, Anazawa T, Kirchner VA, Rizzari MD, Stone J, Matsumoto S, Hammer BE, Balamurugan AN, Kidder LS, Suszynski TM, Avgoustiniatos ES, Stone SG, Tempelman LA, Sutherland DER, Hering BJ, Papas KK. Pancreas oxygen persufflation increases ATP levels as shown by nuclear magnetic resonance. Transplant Proc 2011; 42:2011-5. [PMID: 20692395 DOI: 10.1016/j.transproceed.2010.05.091] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Islet transplantation is a promising treatment for type 1 diabetes. Due to a shortage of suitable human pancreata, high cost, and the large dose of islets presently required for long-term diabetes reversal; it is important to maximize viable islet yield. Traditional methods of pancreas preservation have been identified as suboptimal due to insufficient oxygenation. Enhanced oxygen delivery is a key area of improvement. In this paper, we explored improved oxygen delivery by persufflation (PSF), ie, vascular gas perfusion. METHODS Human pancreata were obtained from brain-dead donors. Porcine pancreata were procured by en bloc viscerectomy from heparinized donation after cardiac death donors and were either preserved by either two-layer method (TLM) or PSF. Following procurement, organs were transported to a 1.5-T magnetic resonance (MR) system for (31)P nuclear magnetic resonance spectroscopy to investigate their bioenergetic status by measuring the ratio of adenosine triphosphate to inorganic phosphate (ATP:P(i)) and for assessing PSF homogeneity by MRI. RESULTS Human and porcine pancreata can be effectively preserved by PSF. MRI showed that pancreatic tissue was homogeneously filled with gas. TLM can effectively raise ATP:P(i) levels in rat pancreata but not in larger porcine pancreata. ATP:P(i) levels were almost undetectable in porcine organs preserved with TLM. When human or porcine organs were preserved by PSF, ATP:P(i) was elevated to levels similar to those observed in rat pancreata. CONCLUSION The methods developed for human and porcine pancreas PSF homogeneously deliver oxygen throughout the organ. This elevates ATP levels during preservation and may improve islet isolation outcomes while enabling the use of marginal donors, thus expanding the usable donor pool.
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Affiliation(s)
- W E Scott
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota, Minneapolis, Minnesota, USA
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Sinha S, Taly AB, Ravishankar S, Prashanth LK, Vasudev MK. Wilson's disease: (31)P and (1)H MR spectroscopy and clinical correlation. Neuroradiology 2010; 52:977-85. [PMID: 20174787 DOI: 10.1007/s00234-010-0661-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Accepted: 01/08/2010] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Proton ((1)H) magnetic resonance spectroscopy (MRS) changes are noted in Wilson's disease (WD). However, there are no studies regarding membrane phospholipid abnormality using (31)P MRS in these patients. We aimed to analyze the striatal spectroscopic abnormalities using (31)P and (1)H MRS in WD. METHODS Forty patients of WD (treated, 29; untreated,11) and 30 controls underwent routine MR image sequences and in vivo 2-D (31)P and (1)H MRS of basal ganglia using an image-selected technique on a 1.5-T MRI scanner. Statistical analysis was done using Student's t test. RESULTS The mean durations of illness and treatment were 6.2 ± 7.4 and 4.8 ± 5.9 years, respectively. MRI images were abnormal in all the patients. (1)H MRS revealed statistically significant reduction of N-acetyl aspartate (NAA)/choline (Cho) and NAA/creatine ratios in striatum ((1)H MRS) of treated patients compared to controls. The mean values of phosphomonoesters (PME) (p < 0.0001), phosphodiesters (PDE) (p < 0.0001), and total phosphorus (TPh) (p < 0.0001) were elevated in patients compared to controls. Statistically significant elevated levels of ratio of PME/PDE (p = 0.05) observed in the striatum were noted in treated patients as compared to controls in the (31)P MRS study. The duration of illness correlated well with increased PME/PDE [p < 0.001], PME/TPh [p < 0.05], and PDE/TPh [p < 0.05] and decreased NAA/Cho [p < 0.05] ratios. There was correlation of MRI score and reduced NAA/Cho ratio with disease severity. The PME/PDE ratio (right) was elevated in the treated group [p < 0.001] compared to untreated group. CONCLUSIONS There is reduced breakdown and/or increased synthesis of membrane phospholipids and increased neuronal damage in basal ganglia in patients with WD.
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Affiliation(s)
- Sanjib Sinha
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
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Effects of pluronic and doxorubicin on drug uptake, cellular metabolism, apoptosis and tumor inhibition in animal models of MDR cancers. J Control Release 2010; 143:290-301. [PMID: 20074598 DOI: 10.1016/j.jconrel.2010.01.004] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Revised: 12/10/2009] [Accepted: 01/04/2010] [Indexed: 01/12/2023]
Abstract
Cancer chemotherapy is believed to be impeded by multidrug resistance (MDR). Pluronic (triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO), PEO-b-PPO-b-PEO) were previously shown to sensitize MDR tumors to antineoplastic agents. This study uses animal models of Lewis lung carcinoma (3LL-M27) and T-lymphocytic leukemia (P388/ADR and P388) derived solid tumors to delineate mechanisms of sensitization of MDR tumors by Pluronic P85 (P85) in vivo. First, non-invasive single photon emission computed tomography (SPECT) and tumor tissue radioactivity sampling demonstrate that intravenous co-administration of P85 with a Pgp substrate, 99Tc-sestamibi, greatly increases the tumor uptake of this substrate in the MDR tumors. Second, 31P magnetic resonance spectroscopy (31P-MRS) in live animals and tumor tissue sampling for ATP suggest that P85 and doxorubicin (Dox) formulations induce pronounced ATP depletion in MDR tumors. Third, these formulations are shown to increase tumor apoptosis in vivo by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and reverse transcription polymerase chain reaction (RT-PCR) for caspases 8 and 9. Altogether, formulation of Dox with P85 results in increased inhibition of the growth solid tumors in mice and represents novel and promising strategy for therapy of drug resistant cancers.
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Kherlopian AR, Song T, Duan Q, Neimark MA, Po MJ, Gohagan JK, Laine AF. A review of imaging techniques for systems biology. BMC SYSTEMS BIOLOGY 2008; 2:74. [PMID: 18700030 PMCID: PMC2533300 DOI: 10.1186/1752-0509-2-74] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Accepted: 08/12/2008] [Indexed: 11/10/2022]
Abstract
This paper presents a review of imaging techniques and of their utility in system biology. During the last decade systems biology has matured into a distinct field and imaging has been increasingly used to enable the interplay of experimental and theoretical biology. In this review, we describe and compare the roles of microscopy, ultrasound, CT (Computed Tomography), MRI (Magnetic Resonance Imaging), PET (Positron Emission Tomography), and molecular probes such as quantum dots and nanoshells in systems biology. As a unified application area among these different imaging techniques, examples in cancer targeting are highlighted.
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Affiliation(s)
- Armen R Kherlopian
- Department of Biomedical Engineering, Columbia University, New York, NY, USA.
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Scott WE, Matsumoto S, Tanaka T, Avgoustiniatos ES, Graham ML, Williams PC, Tempelman LA, Sutherland DE, Hering BJ, Hammer BE, Papas KK. Real-time noninvasive assessment of pancreatic ATP levels during cold preservation. Transplant Proc 2008; 40:403-6. [PMID: 18374082 DOI: 10.1016/j.transproceed.2008.01.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
31P-NMR spectroscopy was utilized to investigate rat and porcine pancreatic ATP:P(i) ratios to assess the efficacy of existing protocols for cold preservation (CP) in maintaining organ quality. Following sacrifice, rat pancreata were immediately excised or left enclosed in the body for 15 minutes of warm ischemia (WI). After excision, rat pancreata were stored at 6 degrees C to 8 degrees C using histidine-tryptophan-ketoglutarate solution (HTK) presaturated with air (S1), HTK presaturated with O2 (S2), or the HTK/perfluorodecalin two-layer method (TLM) with both liquids presaturated with O2 (S3). 31P-NMR spectra were sequentially collected at 3, 6, 9, 12, and 24 hours of CP from pancreata stored with each of the three protocols examined. The ATP:Pi ratio for rat pancreata exposed to 15 minutes of WI and stored with S3 increased during the first 9 hours of CP, approaching values observed for organs procured with no WI. A marked reduction in the ATP:Pi ratio was observed beyond 12 hours of CP with S3. After 6 hours of CP, the ATP:Pi ratio was highest for S3, substantially decreased for S2, and below detection for S1. In sharp contrast to the rat model, ATP was barely detectable in porcine pancreata exposed to minimal warm ischemia (<15 minutes) stored with the TLM regardless of CP time. We conclude that 31P-NMR spectroscopy is a powerful tool that can be used to (1) noninvasively evaluate pancreata prior to islet isolation, (2) assess the efficacy of different preservation protocols, (3) precisely define the timing of reversible versus irreversible damage, and (4) assess whether intervention will extend this timing.
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Affiliation(s)
- W E Scott
- University of Minnesota, Department of Surgery, Diabetes Institute for Immunology and Transplantation, Minneapolis, Minnesota 55455, USA
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Coon AL, Arias-Mendoza F, Colby GP, Cruz-Lobo J, Mocco J, Mack WJ, Komotar RJ, Brown TR, Connolly ES. Correlation of cerebral metabolites with functional outcome in experimental primate stroke using in vivo 1H-magnetic resonance spectroscopy. AJNR Am J Neuroradiol 2006; 27:1053-8. [PMID: 16687542 PMCID: PMC7975755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
BACKGROUND AND PURPOSE Ensuring the translatability of primate stroke models is critical for preclinical testing of cerebroprotective strategies, and such models would benefit from further characterization of the experimental ischemic tissue. Our purpose was to examine the cerebral metabolic response to stroke in baboons with MR spectroscopy and to correlate metabolite levels with functional neurologic outcomes. METHODS Seven baboons underwent 1 hour of middle cerebral artery occlusion. At 3 and 10 days, each animal was imaged with traditional MR imaging and multivoxel proton (1)H-MR spectroscopy, and a neurologic examination was performed. Spectra obtained from the infarcted hemisphere of each animal were compared with the contralateral hemisphere, and metabolite levels were correlated with neurologic outcome scores. RESULTS Spectra obtained at 3 days postischemia revealed prominent lactate (LAC) resonances and attenuated N-acetylaspartate (NAA) peaks in infarcted hemispheres. Ten-day spectra showed persistence of these findings in animals with large strokes (>30% of the hemisphere), with partial normalization of the spectra in animals with small strokes (<30% of the hemisphere). Mean area under the curve from LAC spectra had a negative correlation with functional outcome by 2 different scoring systems (r(2) = 0.72 and 0.73), whereas NAA showed a positive correlation (r(2) = 0.79 and 0.62). CONCLUSIONS The metabolic alterations observed in our primate model of reperfused ischemia by (1)H-MR spectroscopy recapitulate those seen in clinical stroke. Furthermore, correlations between LAC and NAA peaks with functional outcome further suggest that MR spectroscopy may play a role in outcome prediction following cerebral infarction in higher primates.
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Affiliation(s)
- A L Coon
- Department of Neurological Surgery, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
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