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Jordan VC, Sojoodi M, Shroff S, Pagan PG, Barrett SC, Wellen J, Tanabe KK, Chung RT, Caravan P, Gale EM. Molecular magnetic resonance imaging of liver inflammation using an oxidatively activated probe. JHEP Rep 2023; 5:100850. [PMID: 37818152 PMCID: PMC10561122 DOI: 10.1016/j.jhepr.2023.100850] [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] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 07/06/2023] [Accepted: 07/10/2023] [Indexed: 10/12/2023] Open
Abstract
Background & Aims Many liver diseases are driven by inflammation, but imaging to non-invasively diagnose and quantify liver inflammation has been underdeveloped. The inflammatory liver microenvironment is aberrantly oxidising owing in part to reactive oxygen species generated by myeloid leucocytes. We hypothesised that magnetic resonance imaging using the oxidatively activated probe Fe-PyC3A will provide a non-invasive biomarker of liver inflammation. Methods A mouse model of drug-induced liver injury was generated through intraperitoneal injection of a hepatoxic dose of acetaminophen. A mouse model of steatohepatitis was generated via a choline-deficient, l-amino acid defined high-fat diet (CDAHFD). Images were acquired dynamically before and after intravenous injection of Fe-PyC3A. The contrast agent gadoterate meglumine was used as a non-oxidatively activated negative control probe in mice fed CDAHFD. The (post-pre) Fe-PyC3A injection change in liver vs. muscle contrast-to-noise ratio (ΔCNR) recorded 2 min post-injection was correlated with liver function test values, histologic scoring assigned using the NASH Clinical Research Network criteria, and intrahepatic myeloid leucocyte composition determined by flow cytometry. Results For mice receiving i.p. injections of acetaminophen, intrahepatic neutrophil composition correlated poorly with liver test values but positively and significantly with ΔCNR (r = 0.64, p <0.0001). For mice fed CDAHFD, ΔCNR generated by Fe-PyC3A in the left lobe was significantly greater in mice meeting histologic criteria strongly associated with a diagnosis NASH compared to mice where histology was consistent with likely non-NASH (p = 0.0001), whereas no differential effect was observed using gadoterate meglumine. In mice fed CDAHFD, ΔCNR did not correlate strongly with fractional composition of any specific myeloid cell subpopulation as determined by flow cytometry. Conclusions Magnetic resonance imaging using Fe-PyC3A merits further evaluation as a non-invasive biomarker for liver inflammation. Impact and implications Non-invasive tests to diagnose and measure liver inflammation are underdeveloped. Inflammatory cells such as neutrophils release reactive oxygen species which creates an inflammatory liver microenvironment that can drive chemical oxidation. We recently invented a new class of magnetic resonance imaging probe that is made visible to the scanner only after chemical oxidation. Here, we demonstrate how this imaging technology could be applied as a non-invasive biomarker for liver inflammation.
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Affiliation(s)
- Veronica Clavijo Jordan
- Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Mozhdeh Sojoodi
- Harvard Medical School, Boston, MA, USA
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Stuti Shroff
- Harvard Medical School, Boston, MA, USA
- Department of Pathology, Massachusetts General Hospital, Boston, MA, USA
| | - Patricia Gonzalez Pagan
- Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Stephen Cole Barrett
- Harvard Medical School, Boston, MA, USA
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Boston, MA, USA
| | | | - Kenneth K. Tanabe
- Harvard Medical School, Boston, MA, USA
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Raymond T. Chung
- Harvard Medical School, Boston, MA, USA
- Gastroenterology Unit, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
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King RM, Gounis MJ, Schmidt EJ, Leporati A, Gale EM, Bogdanov AA. Molecular Magnetic Resonance Imaging of Aneurysmal Inflammation Using a Redox Active Iron Complex. Invest Radiol 2023; 58:656-662. [PMID: 36822678 PMCID: PMC10401906 DOI: 10.1097/rli.0000000000000960] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
OBJECTIVES Inflammation plays a key role in driving brain aneurysmal instability and rupture, but clinical tools to noninvasively differentiate between inflamed and stable aneurysms are lacking. We hypothesize that imaging oxidative changes in the aneurysmal microenvironment driven by myeloid inflammatory cells may represent a noninvasive biomarker to evaluate rupture risk. In this study, we performed initial evaluation of the oxidatively activated probe Fe-PyC3A as a tool for magnetic resonance imaging (MRI) of inflammation in a rabbit model of saccular aneurysm. MATERIALS AND METHODS The difference in longitudinal relaxivity ( r1 ) in reduced and oxidized states of Fe-PyC3A was measured in water and blood plasma phantoms at 3 T. A rabbit saccular aneurysm model was created by endovascular intervention/elastinolysis with subsequent decellularization in situ. Rabbits were imaged at 4 weeks (n = 4) or 12 weeks (n = 4) after aneurysmal induction, when luminal levels of inflammation reflected by the presence of myeloperoxidase positive cells are relatively high and low, respectively, using a 3 T clinical scanner. Both groups were imaged dynamically using a 2-dimensional T1-weighted fast field echo pulse MRI sequence before and up to 4 minutes postinjection of Fe-PyC3A. Dynamic imaging was then repeated after an injection of gadobutrol (0.1 mmol/kg) as negative control probe. Rabbits from the 12-week aneurysm group were also imaged before and 20 minutes and 3 hours after injection of Fe-PyC3A using an axial respiratory gated turbo-spin echo (TSE) pulse sequence with motion-sensitized driven equilibrium (MSDE) preparation. The MSDE/TSE imaging was repeated before, immediately after dynamic acquisition (20 minutes postinjection), and 3 hours after injection of gadobutrol. Aneurysmal enhancement ratios (ERs) were calculated by dividing the postinjection aneurysm versus skeletal muscle contrast ratio by the preinjection contrast ratio. After imaging, the aneurysms were excised and inflammatory infiltrate was characterized by fluorometric detection of myeloperoxidase activity and calprotectin immunostaining, respectively. RESULTS In vitro relaxometry showed that oxidation of Fe-PyC3A by hydrogen peroxide resulted in a 15-fold increase of r1 at 3 T. Relaxometry in the presence of blood plasma showed no more than a 10% increase of r1 , indicating the absence of strong interaction of Fe-PyC3A with plasma proteins. Dynamic imaging with Fe-PyC3A generated little signal enhancement within the blood pool or adjacent muscle but did generate a transient increase in aneurysmal ER that was significantly greater 4 weeks versus 12 weeks after aneurysm induction (1.6 ± 0.30 vs 1.2 ± 0.03, P < 0.05). Dynamic imaging with gadobutrol generated strong aneurysmal enhancement, but also strong enhancement of the blood and muscle resulting in smaller relative ER change. In the 12-week group of rabbits, MSDE/TSE imaging showed that ER values measured immediately after dynamic MRI (20 minutes postinjection) were significantly higher ( P < 0.05) in the case of Fe-PyC3A (1.25 ± 0.06) than for gadobutrol injection (1.03 ± 0.03). Immunohistochemical corroboration using anticalprotectin antibody showed that leukocyte infiltration into the vessel walls and luminal thrombi was significantly higher in the 4-week group versus 12-week aneurysms (123 ± 37 vs 18 ± 7 cells/mm 2 , P < 0.05). CONCLUSIONS Magnetic resonance imaging using Fe-PyC3A injection in dynamic or delayed acquisition modes was shown to generate a higher magnetic resonance signal enhancement in aneurysms that exhibit higher degree of inflammation. The results of our pilot experiments support further evaluation of MRI using Fe-PyC3A as a noninvasive marker of aneurysmal inflammation.
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Affiliation(s)
- Robert M King
- From the Department of Radiology and New England Center for Stroke Research, UMASS Chan Medical School, Worcester
| | - Matthew J Gounis
- From the Department of Radiology and New England Center for Stroke Research, UMASS Chan Medical School, Worcester
| | - Eric J Schmidt
- From the Department of Radiology and New England Center for Stroke Research, UMASS Chan Medical School, Worcester
| | - Anita Leporati
- From the Department of Radiology and New England Center for Stroke Research, UMASS Chan Medical School, Worcester
| | - Eric M Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown
| | - Alexei A Bogdanov
- From the Department of Radiology and New England Center for Stroke Research, UMASS Chan Medical School, Worcester
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McRae SW, Cleary M, DeRoche D, Martinez FM, Xia Y, Caravan P, Gale EM, Ronald JA, Scholl TJ. Development of a Suite of Gadolinium-Free OATP1-Targeted Paramagnetic Probes for Liver MRI. J Med Chem 2023; 66:6567-6576. [PMID: 37159947 DOI: 10.1021/acs.jmedchem.2c01561] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Five amphiphilic, anionic Mn(II) complexes were synthesized as contrast agents targeted to organic anion transporting polypeptide transporters (OATP) for liver magnetic resonance imaging (MRI). The Mn(II) complexes are synthesized in three steps, each from the commercially available trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA) chelator, with T1-relaxivity of complexes ranging between 2.3 and 3.0 mM-1 s-1 in phosphate buffered saline at an applied field strength of 3.0 T. Pharmacokinetics were assessed in female BALB/c mice by acquiring T1-weighted images dynamically for 70 min after agent administration and determining contrast enhancement and washout in various organs. Uptake of Mn(II) complexes in human OATPs was investigated through in vitro assays using MDA-MB-231 cells engineered to express either OATP1B1 or OATP1B3 isoforms. Our study introduces a new class of Mn-based OATP-targeted contrast that can be broadly tuned via simple synthetic protocols.
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Affiliation(s)
- Sean W McRae
- Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada
| | - Michael Cleary
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Daniel DeRoche
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Francisco M Martinez
- Imaging Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada
| | - Ying Xia
- Imaging Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada
| | - Peter Caravan
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Eric M Gale
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - John A Ronald
- Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada
- Imaging Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada
- Lawson Health Research Institute, London, Ontario N6A 3K7, Canada
| | - Timothy J Scholl
- Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada
- Imaging Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada
- Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7, Canada
- Ontario Institute for Cancer Research, Toronto, Ontario M5G 0A3, Canada
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Bonner BP, Yurista SR, Coll‐Font J, Chen S, Eder RA, Foster AN, Nguyen KD, Caravan P, Gale EM, Nguyen C. Contrast-Enhanced Cardiac Magnetic Resonance Imaging With a Manganese-Based Alternative to Gadolinium for Tissue Characterization of Acute Myocardial Infarction. J Am Heart Assoc 2023; 12:e026923. [PMID: 37042259 PMCID: PMC10227253 DOI: 10.1161/jaha.122.026923] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [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: 05/24/2022] [Accepted: 01/05/2023] [Indexed: 04/13/2023]
Abstract
Background Late gadolinium enhancement cardiac magnetic resonance imaging is an effective and reproducible method for characterizing myocardial infarction. However, gadolinium-based contrast agents are contraindicated in patients with acute and chronic renal insufficiency. In addition, several recent studies have noted tissue deposition of free gadolinium in patients who have undergone serial contrast-enhanced magnetic resonance imaging. There is a clinical need for alternative forms of magnetic resonance imaging contrast agents that are acceptable in the setting of renal insufficiency. Methods and Results Three days after 80 minutes of ischemia/reperfusion of the left anterior descending coronary artery, cardiac magnetic resonance imaging was performed to assess myocardial lesion burden using both contrast agents. Late gadolinium enhancement cardiac magnetic resonance imaging was examined 10 and 15 minutes after contrast injection. Contrast agents were administered in alternating manner with a 2- to 3-hour washout period between contrast agent injections. Lesion evaluation and image processing were performed using Segment Medviso software. Mean infarct size and transmurality, measured using RVP-001, were not different compared with those measured using late gadolinium enhancement images. Bland-Altman analysis demonstrated a nominal bias of 0.13 mL (<1% of average total lesion volume) for RVP-001 in terms of gross infarct size measurement. Conclusions The experimental manganese-based contrast agent RVP-001 appears to be an effective agent for assessment of myocardial infarction location, size, and transmurality, and it may be useful as an alternative to gadolinium-based agents.
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Affiliation(s)
- Benjamin P. Bonner
- Cardiovascular Research CenterMassachusetts General HospitalBostonMA
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
- Louisiana State University Health Sciences CenterNew OrleansLA
| | - Salva R. Yurista
- Cardiovascular Research CenterMassachusetts General HospitalBostonMA
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
- Harvard Medical SchoolBostonMA
| | - Jaume Coll‐Font
- Cardiovascular Research CenterMassachusetts General HospitalBostonMA
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
- Harvard Medical SchoolBostonMA
| | - Shi Chen
- Cardiovascular Research CenterMassachusetts General HospitalBostonMA
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
| | - Robert A. Eder
- Cardiovascular Research CenterMassachusetts General HospitalBostonMA
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
| | - Anna N. Foster
- Cardiovascular Research CenterMassachusetts General HospitalBostonMA
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
| | - Khoi D. Nguyen
- Cardiovascular Research CenterMassachusetts General HospitalBostonMA
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
- Harvard Medical SchoolBostonMA
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
- Harvard Medical SchoolBostonMA
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
- Harvard Medical SchoolBostonMA
| | - Christopher Nguyen
- Cardiovascular Research CenterMassachusetts General HospitalBostonMA
- Athinoula A. Martinos Center for Biomedical ImagingMassachusetts General HospitalBostonMA
- Harvard Medical SchoolBostonMA
- Division of Health Science TechnologyHarvard–Massachusetts Institute of TechnologyCambridgeMA
- Cardiovascular Innovation Research CenterHeart, Vascular, and Thoracic Institute, Cleveland ClinicClevelandOH
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Sargun A, Fisher AL, Wolock AS, Phillips S, Sojoodi M, Khanna S, Babitt JL, Gale EM. A Rationally Designed Complex Replenishes the Transferrin Iron Pool Directly and with High Specificity. J Am Chem Soc 2023; 145:6871-6879. [PMID: 36920018 PMCID: PMC10312995 DOI: 10.1021/jacs.3c00123] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Many forms of anemia are caused or complicated by pathologic restriction of iron (Fe). Chronic inflammation and certain genetic mutations decrease the activity of ferroportin, the only Fe-exporter protein, so that endogenously recycled or nutritionally absorbed Fe cannot be exported to the extracellular Fe carrier protein transferrin for delivery to the bone marrow. Diminished ferroportin activity renders anemia correction challenging as Fe administered intravenously or through nutritional supplementation is trafficked through the ferroportin-transferrin axis. Utilizing judicious application of coordination chemistry principles, we designed an Fe complex (Fe-BBG) with solution thermodynamics and Fe dissociation kinetics optimized to replenish the transferrin-Fe pool rapidly, directly, and with precision. Fe-BBG is unreactive under conditions designed to force redox cycling and production of reactive oxygen species. The BBG ligand has a low affinity for divalent metal ions and does not compete for binding of other endogenously present ions including Cu and Zn. Treatment with Fe-BBG confers anemia correction in a mouse model of iron-refractory iron-deficiency anemia. Repeated exposure to Fe-BBG did not cause adverse clinical chemistry changes or trigger the expression of genes related to oxidative stress or inflammation. Fe-BBG represents the first entry in a promising new class of transferrin-targeted Fe replacement drugs.
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Affiliation(s)
- Artur Sargun
- Athinoula A. Martinos Center for Biomedical Imaging, Department or Radiology, Massachusetts General Hospital/ Harvard Medical School, Boston, Massachusetts, United States
| | - Allison L. Fisher
- Department of Nephrology and Endocrine Unit, Massachusetts General Hospital/ Harvard Medical School, Boston, Massachusetts, United States
| | - Anna S. Wolock
- Athinoula A. Martinos Center for Biomedical Imaging, Department or Radiology, Massachusetts General Hospital/ Harvard Medical School, Boston, Massachusetts, United States
| | - Sydney Phillips
- Department of Nephrology and Endocrine Unit, Massachusetts General Hospital/ Harvard Medical School, Boston, Massachusetts, United States
| | - Mozhdeh Sojoodi
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital/ Harvard Medical School, Boston, Massachusetts, United States
| | - Soumya Khanna
- Department of Nephrology and Endocrine Unit, Massachusetts General Hospital/ Harvard Medical School, Boston, Massachusetts, United States
| | - Jodie L. Babitt
- Department of Nephrology and Endocrine Unit, Massachusetts General Hospital/ Harvard Medical School, Boston, Massachusetts, United States
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Department or Radiology, Massachusetts General Hospital/ Harvard Medical School, Boston, Massachusetts, United States
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Deblonde GJP, Mattocks JA, Wang H, Gale EM, Kersting AB, Zavarin M, Cotruvo JA. Correction to "Characterization of Americium and Curium Complexes with the Protein Lanmodulin: A Potential Macromolecular Mechanism for Actinide Mobility in the Environment". J Am Chem Soc 2022; 144:23708. [PMID: 36521099 DOI: 10.1021/jacs.2c12196] [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: 12/23/2022]
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Park J, Cleary MB, Li D, Mattocks JA, Xu J, Wang H, Mukhopadhyay S, Gale EM, Cotruvo JA. A genetically encoded fluorescent sensor for manganese(II), engineered from lanmodulin. Proc Natl Acad Sci U S A 2022; 119:e2212723119. [PMID: 36508659 PMCID: PMC9907080 DOI: 10.1073/pnas.2212723119] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 11/10/2022] [Indexed: 12/15/2022] Open
Abstract
The design of selective metal-binding sites is a challenge in both small-molecule and macromolecular chemistry. Selective recognition of manganese (II)-the first-row transition metal ion that tends to bind with the lowest affinity to ligands, as described by the Irving-Williams series-is particularly difficult. As a result, there is a dearth of chemical biology tools with which to study manganese physiology in live cells, which would advance understanding of photosynthesis, host-pathogen interactions, and neurobiology. Here we report the rational re-engineering of the lanthanide-binding protein, lanmodulin, into genetically encoded fluorescent sensors for MnII, MnLaMP1 and MnLaMP2. These sensors with effective Kd(MnII) of 29 and 7 µM, respectively, defy the Irving-Williams series to selectively detect MnII in vitro and in vivo. We apply both sensors to visualize kinetics of bacterial labile manganese pools. Biophysical studies indicate the importance of coordinated solvent and hydrophobic interactions in the sensors' selectivity. Our results establish lanmodulin as a versatile scaffold for design of selective protein-based biosensors and chelators for metals beyond the f-block.
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Affiliation(s)
- Jennifer Park
- Department of Chemistry, The Pennsylvania State University, University Park, PA16802
| | - Michael B. Cleary
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital / Harvard Medical School, Charlestown, MA02129
| | - Danyang Li
- Division of Pharmacology and Toxicology, College of Pharmacy, Institute for Cellular and Molecular Biology, and Institute for Neuroscience, The University of Texas at Austin, Austin, TX78712
| | - Joseph A. Mattocks
- Department of Chemistry, The Pennsylvania State University, University Park, PA16802
| | - Jiansong Xu
- Department of Chemistry, The Pennsylvania State University, University Park, PA16802
| | - Huan Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital / Harvard Medical School, Charlestown, MA02129
| | - Somshuvra Mukhopadhyay
- Division of Pharmacology and Toxicology, College of Pharmacy, Institute for Cellular and Molecular Biology, and Institute for Neuroscience, The University of Texas at Austin, Austin, TX78712
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital / Harvard Medical School, Charlestown, MA02129
| | - Joseph A. Cotruvo
- Department of Chemistry, The Pennsylvania State University, University Park, PA16802
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8
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Uzal-Varela R, Rodríguez-Rodríguez A, Wang H, Esteban-Gómez D, Brandariz I, Gale EM, Caravan P, Platas-Iglesias C. Prediction of Gd(III) complex thermodynamic stability. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214606] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Sojoodi M, Erstad DJ, Barrett SC, Salloum S, Zhu S, Qian T, Colon S, Gale EM, Jordan VC, Wang Y, Li S, Ataeinia B, Jalilifiroozinezhad S, Lanuti M, Zukerberg L, Caravan P, Hoshida Y, Chung RT, Bhave G, Lauer GM, Fuchs BC, Tanabe KK. Peroxidasin Deficiency Re-programs Macrophages Toward Pro-fibrolysis Function and Promotes Collagen Resolution in Liver. Cell Mol Gastroenterol Hepatol 2022; 13:1483-1509. [PMID: 35093588 PMCID: PMC9043497 DOI: 10.1016/j.jcmgh.2022.01.015] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 01/16/2022] [Accepted: 01/19/2022] [Indexed: 12/10/2022]
Abstract
BACKGROUND & AIMS During liver fibrosis, tissue repair mechanisms replace necrotic tissue with highly stabilized extracellular matrix proteins. Extracellular matrix stabilization influences the speed of tissue recovery. Here, we studied the expression and function of peroxidasin (PXDN), a peroxidase that uses hydrogen peroxide to cross-link collagen IV during liver fibrosis progression and regression. METHODS Mouse models of liver fibrosis and cirrhosis patients were analyzed for the expression of PXDN in liver and serum. Pxdn-/- and Pxdn+/+ mice were either treated with carbon tetrachloride for 6 weeks to generate toxin-induced fibrosis or fed with a choline-deficient L-amino acid-defined high-fat diet for 16 weeks to create nonalcoholic fatty liver disease fibrosis. Liver histology, quantitative real-time polymerase chain reaction, collagen content, flowcytometry and immunostaining of immune cells, RNA-sequencing, and liver function tests were analyzed. In vivo imaging of liver reactive oxygen species (ROS) was performed using a redox-active iron complex, Fe-PyC3A. RESULTS In human and mouse cirrhotic tissue, PXDN is expressed by stellate cells and is secreted into fibrotic areas. In patients with nonalcoholic fatty liver disease, serum levels of PXDN increased significantly. In both mouse models of liver fibrosis, PXDN deficiency resulted in elevated monocyte and pro-fibrolysis macrophage recruitment into fibrotic bands and caused decreased accumulation of cross-linked collagens. In Pxdn-/- mice, collagen fibers were loosely organized, an atypical phenotype that is reversible upon macrophage depletion. Elevated ROS in Pxdn-/- livers was observed, which can result in activation of hypoxic signaling cascades and may affect signaling pathways involved in macrophage polarization such as TNF-a via NF-kB. Fibrosis resolution in Pxdn-/- mice was associated with significant decrease in collagen content and improved liver function. CONCLUSION PXDN deficiency is associated with increased ROS levels and a hypoxic liver microenvironment that can regulate recruitment and programming of pro-resolution macrophages. Our data implicate the importance of the liver microenvironment in macrophage programming during liver fibrosis and suggest a novel pathway that is involved in the resolution of scar tissue.
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Affiliation(s)
- Mozhdeh Sojoodi
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Derek J. Erstad
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Stephen C. Barrett
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Shadi Salloum
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Shijia Zhu
- Liver Tumor Translational Research Program, Simmons 22 Comprehensive Cancer Center, Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Tongqi Qian
- Liver Tumor Translational Research Program, Simmons 22 Comprehensive Cancer Center, Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Selene Colon
- Division of Nephrology and Hypertension, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Institute for Innovation in Imaging (i3), Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Veronica Clavijo Jordan
- Athinoula A. Martinos Center for Biomedical Imaging, Institute for Innovation in Imaging (i3), Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Yongtao Wang
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Shen Li
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Bahar Ataeinia
- Athinoula A. Martinos Center for Biomedical Imaging, Institute for Innovation in Imaging (i3), Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | | | - Michael Lanuti
- Division of Thoracic Surgery, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, Massachusetts
| | - Lawrence Zukerberg
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging, Institute for Innovation in Imaging (i3), Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Yujin Hoshida
- Liver Tumor Translational Research Program, Simmons 22 Comprehensive Cancer Center, Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Raymond T. Chung
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Gautam Bhave
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Georg M. Lauer
- Liver Center, Division of Gastroenterology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Bryan C. Fuchs
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Kenneth K. Tanabe
- Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts,Correspondence Address correspondence to: Kenneth K. Tanabe, Division of Gastrointestinal and Oncologic Surgery, Massachusetts General Hospital, 55 Fruit St, Boston, MA 02114. tel: (617) 724-3868.
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10
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Wang H, Cleary MB, Lewis LC, Bacon JW, Caravan P, Shafaat HS, Gale EM. Enzyme Control Over Ferric Iron Magnetostructural Properties. Angew Chem Int Ed Engl 2022; 61:e202114019. [PMID: 34814231 PMCID: PMC8935392 DOI: 10.1002/anie.202114019] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [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: 10/15/2021] [Indexed: 01/19/2023]
Abstract
Fe3+ complexes in aqueous solution can exist as discrete mononuclear species or multinuclear magnetically coupled species. Stimuli-driven change to Fe3+ speciation represents a powerful mechanistic basis for magnetic resonance sensor technology, but ligand design strategies to exert precision control of aqueous Fe3+ magnetostructural properties are entirely underexplored. In pursuit of this objective, we rationally designed a ligand to strongly favor a dinuclear μ-oxo-bridged and antiferromagnetically coupled complex, but which undergoes carboxylesterase mediated transformation to a mononuclear high-spin Fe3+ chelate resulting in substantial T1 -relaxivity increase. The data communicated demonstrate proof of concept for a novel and effective strategy to exert biochemical control over aqueous Fe3+ magnetic, structural, and relaxometric properties.
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Affiliation(s)
- Huan Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Michael B. Cleary
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Luke C. Lewis
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, 43210, United States
| | - Jeffrey W. Bacon
- Department of Chemistry, Boston University, Boston, Massachusetts, 02215, United States
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States,Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Hannah S. Shafaat
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, 43210, United States
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States,Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
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11
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Wang H, Cleary MB, Lewis LC, Bacon JW, Caravan P, Shafaat HS, Gale EM. Enzyme Control Over Ferric Iron Magnetostructural Properties. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Huan Wang
- Athinoula A. Martinos Center for Biomedical Imaging
- Institute for Innovation in Imaging Department of Radiology Massachusetts General Hospital/Harvard Medical School 149 Thirteenth Street Charlestown MA 02129 USA
| | - Michael B. Cleary
- Athinoula A. Martinos Center for Biomedical Imaging
- Institute for Innovation in Imaging Department of Radiology Massachusetts General Hospital/Harvard Medical School 149 Thirteenth Street Charlestown MA 02129 USA
| | - Luke C. Lewis
- Department of Chemistry and Biochemistry The Ohio State University Columbus OH 43210 USA
| | | | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging
- Institute for Innovation in Imaging Department of Radiology Massachusetts General Hospital/Harvard Medical School 149 Thirteenth Street Charlestown MA 02129 USA
| | - Hannah S. Shafaat
- Department of Chemistry and Biochemistry The Ohio State University Columbus OH 43210 USA
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging
- Institute for Innovation in Imaging Department of Radiology Massachusetts General Hospital/Harvard Medical School 149 Thirteenth Street Charlestown MA 02129 USA
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12
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Deblonde GJP, Mattocks JA, Wang H, Gale EM, Kersting AB, Zavarin M, Cotruvo JA. Characterization of Americium and Curium Complexes with the Protein Lanmodulin: A Potential Macromolecular Mechanism for Actinide Mobility in the Environment. J Am Chem Soc 2021; 143:15769-15783. [PMID: 34542285 DOI: 10.1021/jacs.1c07103] [Citation(s) in RCA: 16] [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: 12/17/2022]
Abstract
Anthropogenic radionuclides, including long-lived heavy actinides such as americium and curium, represent the primary long-term challenge for management of nuclear waste. The potential release of these wastes into the environment necessitates understanding their interactions with biogeochemical compounds present in nature. Here, we characterize the interactions between the heavy actinides, Am3+ and Cm3+, and the natural lanthanide-binding protein, lanmodulin (LanM). LanM is produced abundantly by methylotrophic bacteria, including Methylorubrum extorquens, that are widespread in the environment. We determine the first stability constant for an Am3+-protein complex (Am3LanM) and confirm the results with Cm3LanM, indicating a ∼5-fold higher affinity than that for lanthanides with most similar ionic radius, Nd3+ and Sm3+, and making LanM the strongest known heavy actinide-binding protein. The protein's high selectivity over 243Am's daughter nuclide 239Np enables lab-scale actinide-actinide separations as well as provides insight into potential protein-driven mobilization for these actinides in the environment. The luminescence properties of the Cm3+-LanM complex, and NMR studies of Gd3+-LanM, reveal that lanmodulin-bound f-elements possess two coordinated solvent molecules across a range of metal ionic radii. Finally, we show under a wide range of environmentally relevant conditions that lanmodulin effectively outcompetes desferrioxamine B, a hydroxamate siderophore previously proposed to be important in trivalent actinide mobility. These results suggest that natural lanthanide-binding proteins such as lanmodulin may play important roles in speciation and mobility of actinides in the environment; it also suggests that protein-based biotechnologies may provide a new frontier in actinide remediation, detection, and separations.
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Affiliation(s)
- Gauthier J-P Deblonde
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States.,Glenn T. Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Joseph A Mattocks
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Huan Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Eric M Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Annie B Kersting
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States.,Glenn T. Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Mavrik Zavarin
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States.,Glenn T. Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Joseph A Cotruvo
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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13
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Zhou IY, Ramsay IA, Ay I, Pantazopoulos P, Rotile NJ, Wong A, Caravan P, Gale EM. Positron Emission Tomography-Magnetic Resonance Imaging Pharmacokinetics, In Vivo Biodistribution, and Whole-Body Elimination of Mn-PyC3A. Invest Radiol 2021; 56:261-270. [PMID: 33136686 PMCID: PMC7933117 DOI: 10.1097/rli.0000000000000736] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [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: 11/26/2022]
Abstract
OBJECTIVES Mn-PyC3A is an experimental manganese (Mn)-based extracellular fluid magnetic resonance imaging (MRI) contrast agent that is being evaluated as a direct replacement for clinical gadolinium (Gd)-based contrast agents. The goals of this study were to use simultaneous positron emission tomography (PET)-MRI to (1) compare the whole-body pharmacokinetics, biodistribution, and elimination of Mn-PyC3A with the liver-specific contrast agent mangafodipir (Mn-DPDP), (2) determine the pharmacokinetics and fractional excretion of Mn-PyC3A in a rat model of renal impairment, and (3) compare whole-body elimination of Mn-PyC3A to gadoterate (Gd-DOTA) in a rat model of renal impairment. METHODS Mn-PyC3A and Mn-DPDP were radiolabeled with the positron emitting isotope Mn-52 via Mn2+ exchange with 52MnCl2. Dynamic simultaneous PET-MRI was used to measure whole-body pharmacokinetics and biodistribution of Mn-52 immediately and out to 7 days after an intravenous 0.2 mmol/kg dose of [52Mn]Mn-PyC3A to normal or to 5/6 nephrectomy rats or a 0.01 mmol/kg dose of [52Mn]Mn-DPDP to normal rats. The fractional excretion and 1- and 7-day biodistribution in rats after the injection of 2.0 mmol/kg [52Mn]Mn-PyC3A (n = 11 per time point) or 2.0 mmol/kg Gd-DOTA (n = 8 per time point) were quantified by gamma counting or Gd elemental analysis, respectively. Comparisons of Mn-PyC3A pharmacokinetics and in vivo biodistribution in normal and 5/6 nephrectomy rats and comparisons of ex vivo Mn versus Gd biodistribution data in 5/6 nephrectomy were made with an unpaired t test. RESULTS Dynamic PET-MRI data demonstrate that both [52Mn]Mn-PyC3A and [52Mn]Mn-DPDP were eliminated by mixed renal and hepatobiliary elimination but that a greater fraction of [52Mn]Mn-PyC3A was eliminated by renal filtration. Whole-body PET images show that Mn-52 from [52Mn]Mn-PyC3A was efficiently eliminated from the body, whereas Mn-52 from [52Mn]Mn-DPDP was retained throughout the body. The blood elimination half-life of [52Mn]Mn-PyC3A in normal and 5/6 nephrectomy rats was 13 ± 3.5 minutes and 23 ± 12 minutes, respectively (P = 0.083). Area under the curve between 0 and 60 minutes postinjection (AUC0-60) in the bladder of normal and 5/6 nephrectomy rats was 2600 ± 1700 %ID/cc*min and 750 ± 180 %ID/cc*min, respectively (P = 0.024), whereas AUC0-60 in the liver of normal and 5/6 nephrectomy rats was 33 ± 13 %ID/cc*min and 71 ± 16 %ID/cc*min, respectively (P = 0.011), indicating increased hepatobiliary elimination in 5/6 nephrectomy rats. The %IDs of Mn from [52Mn]Mn-PyC3A and Gd from Gd-DOTA recovered from 5/6 nephrectomy rats 1 day after injection were 2.0 ± 1.1 and 1.3 ± 0.34, respectively (P = 0.10) and 7 days after injection were 0.14 ± 0.11 and 0.41 ± 0.24, respectively (P = 0.0041). CONCLUSIONS Mn-PyC3A has different pharmacokinetics and is more efficiently eliminated than Mn-DPDP in normal rats. Mn-PyC3A is efficiently eliminated from both normal and 5/6 nephrectomy rats, with increased fractional hepatobiliary excretion from 5/6 nephrectomy rats. Mn-PyC3A is more completely eliminated than Gd-DOTA from 5/6 nephrectomy rats after 7 days.
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Affiliation(s)
| | - Ian A Ramsay
- From the Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School
| | - Ilknur Ay
- From the Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School
| | - Pamela Pantazopoulos
- From the Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School
| | - Nicholas J Rotile
- From the Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School
| | - Alison Wong
- From the Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School
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14
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Wang H, Wong A, Lewis LC, Nemeth GR, Jordan VC, Bacon JW, Caravan P, Shafaat HS, Gale EM. Rational Ligand Design Enables pH Control over Aqueous Iron Magnetostructural Dynamics and Relaxometric Properties. Inorg Chem 2020; 59:17712-17721. [PMID: 33216537 DOI: 10.1021/acs.inorgchem.0c02923] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Complexes of Fe3+ engage in rich aqueous solution speciation chemistry in which discrete molecules can react with solvent water to form multinuclear μ-oxo and μ-hydroxide bridged species. Here we demonstrate how pH- and concentration-dependent equilibration between monomeric and μ-oxo-bridged dimeric Fe3+ complexes can be controlled through judicious ligand design. We purposed this chemistry to develop a first-in-class Fe3+-based MR imaging probe, Fe-PyCy2AI, that undergoes relaxivity change via pH-mediated control of monomer vs dimer speciation. The monomeric complex exists in a S = 5/2 configuration capable of inducing efficient T1-relaxation, whereas the antiferromagnetically coupled dimeric complex is a much weaker relaxation agent. The mechanisms underpinning the pH dependence on relaxivity were interrogated by using a combination of pH potentiometry, 1H and 17O relaxometry, electronic absorption spectroscopy, bulk magnetic susceptibility, electron paramagnetic resonance spectroscopy, and X-ray crystallography measurements. Taken together, the data demonstrate that PyCy2AI forms a ternary complex with high-spin Fe3+ and a rapidly exchanging water coligand, [Fe(PyCy2AI)(H2O)]+ (ML), which can deprotonate to form the high-spin complex [Fe(PyCy2AI)(OH)] (ML(OH)). Under titration conditions of 7 mM Fe complex, water coligand deprotonation occurs with an apparent pKa 6.46. Complex ML(OH) dimerizes to form the antiferromagnetically coupled dimeric complex [(Fe(PyCy2AI))2O] ((ML)2O) with an association constant (Ka) of 5.3 ± 2.2 mM-1. The relaxivity of the monomeric complexes are between 7- and 18-fold greater than the antiferromagnetically coupled dimer at applied field strengths ranging between 1.4 and 11.7 T. ML(OH) and (ML)2O interconvert rapidly within the pH 6.0-7.4 range that is relevant to human pathophysiology, resulting in substantial observed relaxivity change. Controlling Fe3+ μ-oxo bridging interactions through rational ligand design and in response to local chemical environment offers a robust mechanism for biochemically responsive MR signal modulation.
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Affiliation(s)
| | | | - Luke C Lewis
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | | | | | - Jeffrey W Bacon
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | | | - Hannah S Shafaat
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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15
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Gupta A, Caravan P, Price WS, Platas-Iglesias C, Gale EM. Applications for Transition-Metal Chemistry in Contrast-Enhanced Magnetic Resonance Imaging. Inorg Chem 2020; 59:6648-6678. [PMID: 32367714 DOI: 10.1021/acs.inorgchem.0c00510] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Contrast-enhanced magnetic resonance imaging (MRI) is an indispensable tool for diagnostic medicine. However, safety concerns related to gadolinium in commercial MRI contrast agents have emerged in recent years. For patients suffering from severe renal impairment, there is an important unmet medical need to perform contrast-enhanced MRI without gadolinium. There are also concerns over the long-term effects of retained gadolinium within the general patient population. Demand for gadolinium-free MRI contrast agents is driving a new wave of inorganic chemistry innovation as researchers explore paramagnetic transition-metal complexes as potential alternatives. Furthermore, advances in personalized care making use of molecular-level information have motivated inorganic chemists to develop MRI contrast agents that can detect pathologic changes at the molecular level. Recent studies have highlighted how reaction-based modulation of transition-metal paramagnetism offers a highly effective mechanism to achieve MRI contrast enhancement that is specific to biochemical processes. This Viewpoint highlights how recent advances in transition-metal chemistry are leading the way for a new generation of MRI contrast agents.
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Affiliation(s)
- Abhishek Gupta
- Nanoscale Organisation and Dynamics Group, School of Science and Health, Western Sydney University, Penrith, New South Wales 2751, Australia.,Ingham Institute of Applied Medical Research, Liverpool, New South Wales 2170, Australia
| | | | - William S Price
- Nanoscale Organisation and Dynamics Group, School of Science and Health, Western Sydney University, Penrith, New South Wales 2751, Australia.,Ingham Institute of Applied Medical Research, Liverpool, New South Wales 2170, Australia
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, A Coruña, Galicia 15071, Spain
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16
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Wang H, Jordan VC, Ramsay IA, Sojoodi M, Fuchs BC, Tanabe KK, Caravan P, Gale EM. Molecular Magnetic Resonance Imaging Using a Redox-Active Iron Complex. J Am Chem Soc 2019; 141:5916-5925. [PMID: 30874437 DOI: 10.1021/jacs.9b00603] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We introduce a redox-active iron complex, Fe-PyC3A, as a biochemically responsive MRI contrast agent. Switching between Fe3+-PyC3A and Fe2+-PyC3A yields a full order of magnitude relaxivity change that is field-independent between 1.4 and 11.7 T. The oxidation of Fe2+-PyC3A to Fe3+-PyC3A by hydrogen peroxide is very rapid, and we capitalized on this behavior for the molecular imaging of acute inflammation, which is characterized by elevated levels of reactive oxygen species. Injection of Fe2+-PyC3A generates strong, selective contrast enhancement of inflamed pancreatic tissue in a mouse model (caerulein/LPS model). No significant signal enhancement is observed in normal pancreatic tissue (saline-treated mice). Importantly, signal enhancement of the inflamed pancreas correlates strongly and significantly with ex vivo quantitation of the pro-inflammatory biomarker myeloperoxidase. This is the first example of using metal ion redox for the MR imaging of pathologic change in vivo. Redox-active Fe3+/2+ complexes represent a new design paradigm for biochemically responsive MRI contrast agents.
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Affiliation(s)
- Huan Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology , Massachusetts General Hospital/Harvard Medical School , 149 Thirteenth Street , Charlestown , Massachusetts 02129 , United States
| | - Veronica Clavijo Jordan
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology , Massachusetts General Hospital/Harvard Medical School , 149 Thirteenth Street , Charlestown , Massachusetts 02129 , United States.,Institute for Innovation in Imaging, Department of Radiology , Massachusetts General Hospital , 55 Fruit Street , Boston , Massachusetts 02114 , United States
| | - Ian A Ramsay
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology , Massachusetts General Hospital/Harvard Medical School , 149 Thirteenth Street , Charlestown , Massachusetts 02129 , United States
| | - Mozhdeh Sojoodi
- Division of Surgical Oncology , Massachusetts General Hospital/Harvard Medical School , WRN401, 55 Fruit Street , Boston , Massachusetts 02114 , United States
| | - Bryan C Fuchs
- Division of Surgical Oncology , Massachusetts General Hospital/Harvard Medical School , WRN401, 55 Fruit Street , Boston , Massachusetts 02114 , United States
| | - Kenneth K Tanabe
- Division of Surgical Oncology , Massachusetts General Hospital/Harvard Medical School , WRN401, 55 Fruit Street , Boston , Massachusetts 02114 , United States
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology , Massachusetts General Hospital/Harvard Medical School , 149 Thirteenth Street , Charlestown , Massachusetts 02129 , United States.,Institute for Innovation in Imaging, Department of Radiology , Massachusetts General Hospital , 55 Fruit Street , Boston , Massachusetts 02114 , United States
| | - Eric M Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology , Massachusetts General Hospital/Harvard Medical School , 149 Thirteenth Street , Charlestown , Massachusetts 02129 , United States
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17
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Abstract
Tens of millions of contrast-enhanced magnetic resonance imaging (MRI) exams are performed annually around the world. The contrast agents, which improve diagnostic accuracy, are almost exclusively small, hydrophilic gadolinium(III) based chelates. In recent years concerns have arisen surrounding the long-term safety of these compounds, and this has spurred research into alternatives. There has also been a push to develop new molecularly targeted contrast agents or agents that can sense pathological changes in the local environment. This comprehensive review describes the state of the art of clinically approved contrast agents, their mechanism of action, and factors influencing their safety. From there we describe different mechanisms of generating MR image contrast such as relaxation, chemical exchange saturation transfer, and direct detection and the types of molecules that are effective for these purposes. Next we describe efforts to make safer contrast agents either by increasing relaxivity, increasing resistance to metal ion release, or by moving to gadolinium(III)-free alternatives. Finally we survey approaches to make contrast agents more specific for pathology either by direct biochemical targeting or by the design of responsive or activatable contrast agents.
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Affiliation(s)
- Jessica Wahsner
- Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Aurora Rodríguez-Rodríguez
- Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
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18
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Wang J, Wang H, Ramsay IA, Erstad DJ, Fuchs BC, Tanabe KK, Caravan P, Gale EM. Manganese-Based Contrast Agents for Magnetic Resonance Imaging of Liver Tumors: Structure-Activity Relationships and Lead Candidate Evaluation. J Med Chem 2018; 61:8811-8824. [PMID: 30204438 DOI: 10.1021/acs.jmedchem.8b00964] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Gd-based MRI contrast agents (GBCAs) have come under intense regulatory scrutiny due to concerns of Gd retention and delayed toxicity. Three GBCAs comprising acyclic Gd chelates, the class of GBCA most prone to Gd release, are no longer marketed in Europe. Of particular concern are the acyclic chelates that remain available for liver scans, where there is an unmet diagnostic need and no replacement technology. To address this concern, we evaluated our previously reported Mn-based MRI contrast agent, Mn-PyC3A, and nine newly synthesized derivatives as liver specific MRI contrast agents. Within this focused library the transient liver uptake and rate of blood clearance are directly correlated with log P. The complex Mn-PyC3A-3-OBn emerged as the lead candidate due to a combination of high relaxivity, rapid blood clearance, and avid hepatocellular uptake. Mn-PyC3A-3-OBn rendered liver tumors conspicuously hypo-intense in a murine model and is wholly eliminated within 24 h of injection.
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Affiliation(s)
| | | | | | - Derek J Erstad
- Department of Surgical Oncology , Massachusetts General Hospital/Harvard Medical School , WRN401, 55 Fruit Street , Boston , Massachusetts 02114 , United States
| | - Bryan C Fuchs
- Department of Surgical Oncology , Massachusetts General Hospital/Harvard Medical School , WRN401, 55 Fruit Street , Boston , Massachusetts 02114 , United States
| | - Kenneth K Tanabe
- Department of Surgical Oncology , Massachusetts General Hospital/Harvard Medical School , WRN401, 55 Fruit Street , Boston , Massachusetts 02114 , United States
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19
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Abstract
We discuss how the recent revelation that gadolinium (Gd) from commercially available MRI contrast agents is irreversibly and cumulatively deposited in the central nervous system is driving innovation toward Gd-free contrast agents for neuroradiology.
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Affiliation(s)
- Eric M. Gale
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
| | - Peter Caravan
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
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20
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Dai L, Jones CM, Chan WTK, Pham TA, Ling X, Gale EM, Rotile NJ, Tai WCS, Anderson CJ, Caravan P, Law GL. Chiral DOTA chelators as an improved platform for biomedical imaging and therapy applications. Nat Commun 2018; 9:857. [PMID: 29487362 PMCID: PMC5829242 DOI: 10.1038/s41467-018-03315-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 02/02/2018] [Indexed: 11/28/2022] Open
Abstract
Despite established clinical utilisation, there is an increasing need for safer, more inert gadolinium-based contrast agents, and for chelators that react rapidly with radiometals. Here we report the syntheses of a series of chiral DOTA chelators and their corresponding metal complexes and reveal properties that transcend the parent DOTA compound. We incorporated symmetrical chiral substituents around the tetraaza ring, imparting enhanced rigidity to the DOTA cavity, enabling control over the range of stereoisomers of the lanthanide complexes. The Gd chiral DOTA complexes are shown to be orders of magnitude more inert to Gd release than [GdDOTA]−. These compounds also exhibit very-fast water exchange rates in an optimal range for high field imaging. Radiolabeling studies with (Cu-64/Lu-177) also demonstrate faster labelling properties. These chiral DOTA chelators are alternative general platforms for the development of stable, high relaxivity contrast agents, and for radiometal complexes used for imaging and/or therapy. MRI contrast agents containing the rare earth metal gadolinium are very effective, yet unstable and thus potentially hazardous. Here, the authors developed complexes between gadolinium and the scaffolding compound DOTA with increased stability, which also lend themselves to radiometal labelling.
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Affiliation(s)
- Lixiong Dai
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China
| | - Chloe M Jones
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, 02129, United States
| | - Wesley Ting Kwok Chan
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China
| | - Tiffany A Pham
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213, United States
| | - Xiaoxi Ling
- Department of Medicine, University of Pittsburgh, Pittsburgh, 15261, Pennsylvania, United States
| | - Eric M Gale
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, 02129, United States
| | - Nicholas J Rotile
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, 02129, United States
| | - William Chi-Shing Tai
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China
| | - Carolyn J Anderson
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213, United States. .,Department of Medicine, University of Pittsburgh, Pittsburgh, 15261, Pennsylvania, United States. .,Departments of Pharmacology & Chemical Biology and Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213, United States.
| | - Peter Caravan
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, 02129, United States.
| | - Ga-Lai Law
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China.
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Farrar CT, Gale EM, Kennan R, Ramsay I, Masia R, Arora G, Looby K, Wei L, Kalpathy-Cramer J, Bunzel MM, Zhang C, Zhu Y, Akiyama TE, Klimas M, Pinto S, Diyabalanage H, Tanabe KK, Humblet V, Fuchs BC, Caravan P. CM-101: Type I Collagen-targeted MR Imaging Probe for Detection of Liver Fibrosis. Radiology 2017; 287:581-589. [PMID: 29156148 DOI: 10.1148/radiol.2017170595] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Purpose To evaluate the biodistribution, metabolism, and pharmacokinetics of a new type I collagen-targeted magnetic resonance (MR) probe, CM-101, and to assess its ability to help quantify liver fibrosis in animal models. Materials and Methods Biodistribution, pharmacokinetics, and stability of CM-101 in rats were measured with mass spectrometry. Bile duct-ligated (BDL) and sham-treated rats were imaged 19 days after the procedure by using a 1.5-T clinical MR imaging unit. Mice were treated with carbon tetrachloride (CCl4) or with vehicle two times a week for 10 weeks and were imaged with a 7.0-T preclinical MR imaging unit at baseline and 1 week after the last CCl4 treatment. Animals were imaged before and after injection of 10 µmol/kg CM-101. Change in contrast-to-noise ratio (ΔCNR) between liver and muscle tissue after CM-101 injection was used to quantify liver fibrosis. Liver tissue was analyzed for Sirius Red staining and hydroxyproline content. The institutional subcommittee for research animal care approved all in vivo procedures. Results CM-101 demonstrated rapid blood clearance (half-life = 6.8 minutes ± 2.4) and predominately renal elimination in rats. Biodistribution showed low tissue gadolinium levels at 24 hours (<3.9% injected dose [ID]/g ± 0.6) and 10-fold lower levels at 14 days (<0.33% ID/g ± 12) after CM-101 injection with negligible accumulation in bone (0.07% ID/g ± 0.02 and 0.010% ID/g ± 0.004 at 1 and 14 days, respectively). ΔCNR was significantly (P < .001) higher in BDL rats (13.6 ± 3.2) than in sham-treated rats (5.7 ± 4.2) and in the CCl4-treated mice (18.3 ± 6.5) compared with baseline values (5.2 ± 1.0). Conclusion CM-101 demonstrated fast blood clearance and whole-body elimination, negligible accumulation of gadolinium in bone or tissue, and robust detection of fibrosis in rat BDL and mouse CCl4 models of liver fibrosis. © RSNA, 2017 Online supplemental material is available for this article.
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Affiliation(s)
- Christian T Farrar
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Eric M Gale
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Richard Kennan
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Ian Ramsay
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Ricard Masia
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Gunisha Arora
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Kailyn Looby
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Lan Wei
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Jayashree Kalpathy-Cramer
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Michelle M Bunzel
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Chunlian Zhang
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Yonghua Zhu
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Taro E Akiyama
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Michael Klimas
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Shirly Pinto
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Himashinie Diyabalanage
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Kenneth K Tanabe
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Valerie Humblet
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Bryan C Fuchs
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
| | - Peter Caravan
- From the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129 (C.T.F., E.M.G., I.R., J.K., P.C.); Merck Research Laboratories, Kenilworth, NJ (R.K., M.M.B., C.Z., Y.Z., T.E.A., M.K., S.P.); Collagen Medical, Belmont, Mass (I.R., H.D., V.H.); Departments of Pathology (R.M.) and Surgical Oncology (G.A., K.L., L.W., K.K.T., B.C.F.), Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, Mass; and Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Mass (P.C.)
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Gale EM, Wey HY, Ramsay I, Yen YF, Sosnovik DE, Caravan P. A Manganese-based Alternative to Gadolinium: Contrast-enhanced MR Angiography, Excretion, Pharmacokinetics, and Metabolism. Radiology 2017; 286:865-872. [PMID: 29117483 DOI: 10.1148/radiol.2017170977] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Purpose To compare intravascular contrast enhancement produced by the manganese-based magnetic resonance (MR) imaging contrast agent manganese-N-picolyl-N,N',N'-trans-1,2-cyclohexenediaminetriacetate (Mn-PyC3A) to gadopentetate dimeglumine (Gd-DTPA) and to evaluate the excretion, pharmacokinetics, and metabolism of Mn-PyC3A. Materials and Methods Contrast material-enhanced MR angiography was performed in baboons (Papio anubis; n = 4) by using Mn-PyC3A and Gd-DTPA. Dynamic imaging was performed for 60 minutes following Mn-PyC3A injection to monitor distribution and elimination. Serial blood sampling was performed to quantify manganese and gadolinium plasma clearance by using inductively coupled plasma mass spectrometry and to characterize Mn-PyC3A metabolism by using high-performance liquid chromatography. Intravascular contrast enhancement in the abdominal aorta and brachiocephalic artery was quantified by measuring contrast-to-noise ratios (CNRs) versus muscle at 9 seconds following Mn-PyC3A or Gd-DTPA injection. Plasma pharmacokinetics were modeled with a biexponential function, and data were compared with a paired t test. Results Aorta versus muscle CNR (mean ± standard deviation) with Mn-PyC3A and Gd-DTPA was 476 ± 77 and 538 ± 120, respectively (P = .11). Brachiocephalic artery versus muscle CNR was 524 ± 55 versus 518 ± 140, respectively (P = .95). Mn-PyC3A was eliminated via renal and hepatobiliary excretion with similar pharmacokinetics to Gd-DTPA (area under the curve between 0 and 30 minutes, 20.2 ± 3.1 and 17.0 ± 2.4, respectively; P = .23). High-performance liquid chromatography revealed no evidence of Mn-PyC3A biotransformation. Conclusion Mn-PyC3A enables contrast-enhanced MR angiography with comparable contrast enhancement to gadolinium-based agents and may overcome concerns regarding gadolinium-associated toxicity and retention. © RSNA, 2017 Online supplemental material is available for this article.
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Affiliation(s)
- Eric M Gale
- From the Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129
| | - Hsiao-Ying Wey
- From the Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129
| | - Ian Ramsay
- From the Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129
| | - Yi-Fen Yen
- From the Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129
| | - David E Sosnovik
- From the Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129
| | - Peter Caravan
- From the Athinoula A. Martinos Center for Biomedical Imaging and the Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth St, Suite 2301, Charlestown, MA 02129
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Truong PT, Gale EM, Dzul SP, Stemmler TL, Harrop TC. Steric Enforcement about One Thiolate Donor Leads to New Oxidation Chemistry in a NiSOD Model Complex. Inorg Chem 2017; 56:7761-7780. [PMID: 28459242 DOI: 10.1021/acs.inorgchem.7b00485] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ni-containing superoxide dismutase (NiSOD) represents an unusual member of the SOD family due to the presence of oxygen-sensitive Ni-SCys bonds at its active site. Reported in this account is the synthesis and properties of the NiII complex of the N3S2 ligand [N3S2Me2]3- ([N3S2Me2]3- = deprotonated form of 2-((2-mercapto-2-methylpropyl)(pyridin-2-ylmethyl)amino)-N-(2-mercaptoethyl)acetamide), namely Na[Ni(N3S2Me2)] (2), as a NiSOD model that features sterically robust gem-(CH3)2 groups on the thiolate α-C positioned trans to the carboxamide. The crystal structure of 2, coupled with spectroscopic measurements from 1H NMR, X-ray absorption, IR, UV-vis, and mass spectrometry (MS), reveal a planar NiII (S = 0) ion coordinated by only the N2S2 basal donors of the N3S2 ligand. While the structure and spectroscopic properties of 2 resemble those of NiSODred and other models, the asymmetric S ligands open up new reaction paths upon chemical oxidation. One unusual oxidation product is the planar NiII-N3S complex [Ni(Lox)] (5; Lox = 2-(5,5-dimethyl-2-(pyridin-2-yl)thiazolidin-3-yl)-N-(2-mercaptoethyl)acetamide), where two-electron oxidation takes place at the substituted thiolate and py-CH2 carbon to generate a thiazolidine heterocycle. Electrochemical measurements of 2 reveal irreversible events wholly consistent with thiolate redox, which were identified by comparison to the ZnII complex Na[Zn(N3S2Me2)] (3). Although no reaction is observed between 2 and azide, reaction of 2 with superoxide produces multiple products on the basis of UV-vis and MS data, one of which is 5. Density functional theory (DFT) computations suggest that the HOMO in 2 is π* with primary contributions from Ni-dπ/S-pπ orbitals. These contributions can be modulated and biased toward Ni when electron-withdrawing groups are placed on the thiolate α-C. Analysis of the oxidized five-coordinate species 2ox* by DFT reveal a singly occupied spin-up (α) MO that is largely thiolate based, which supports the proposed NiIII-thiolate/NiII-thiyl radical intermediates that ultimately yield 5 and other products.
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Affiliation(s)
- Phan T Truong
- Department of Chemistry and Center for Metalloenzyme Studies, The University of Georgia , 140 Cedar Street, Athens, Georgia 30602, United States
| | - Eric M Gale
- Department of Chemistry and Center for Metalloenzyme Studies, The University of Georgia , 140 Cedar Street, Athens, Georgia 30602, United States
| | - Stephen P Dzul
- Departments of Pharmaceutical Sciences, Biochemistry and Molecular Biology, Wayne State University , Detroit, Michigan 48201, United States
| | - Timothy L Stemmler
- Departments of Pharmaceutical Sciences, Biochemistry and Molecular Biology, Wayne State University , Detroit, Michigan 48201, United States
| | - Todd C Harrop
- Department of Chemistry and Center for Metalloenzyme Studies, The University of Georgia , 140 Cedar Street, Athens, Georgia 30602, United States
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Gale EM, Caravan P, Rao AG, McDonald RJ, Winfeld M, Fleck RJ, Gee MS. Gadolinium-based contrast agents in pediatric magnetic resonance imaging. Pediatr Radiol 2017; 47:507-521. [PMID: 28409250 DOI: 10.1007/s00247-017-3806-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/16/2016] [Accepted: 02/10/2017] [Indexed: 12/17/2022]
Abstract
Gadolinium-based contrast agents can increase the accuracy and expediency of an MRI examination. However the benefits of a contrast-enhanced scan must be carefully weighed against the well-documented risks associated with administration of exogenous contrast media. The purpose of this review is to discuss commercially available gadolinium-based contrast agents (GBCAs) in the context of pediatric radiology. We discuss the chemistry, regulatory status, safety and clinical applications, with particular emphasis on imaging of the blood vessels, heart, hepatobiliary tree and central nervous system. We also discuss non-GBCA MRI contrast agents that are less frequently used or not commercially available.
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Affiliation(s)
- Eric M Gale
- Department of Radiology, The Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Peter Caravan
- Department of Radiology, The Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Anil G Rao
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Robert J McDonald
- Department of Radiology, College of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Matthew Winfeld
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Robert J Fleck
- Department of Pediatric Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Michael S Gee
- Division of Pediatric Imaging, Department of Radiology, MassGeneral Hospital for Children, Harvard Medical School, 55 Fruit St., Ellison 237, Boston, MA, 02114, USA.
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Gale EM, Jones CM, Ramsay I, Farrar CT, Caravan P. A Janus Chelator Enables Biochemically Responsive MRI Contrast with Exceptional Dynamic Range. J Am Chem Soc 2016; 138:15861-15864. [PMID: 27960350 PMCID: PMC5328420 DOI: 10.1021/jacs.6b10898] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [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: 12/25/2022]
Abstract
We introduce a new biochemically responsive Mn-based MRI contrast agent that provides a 9-fold change in relaxivity via switching between the Mn3+ and Mn2+ oxidation states. Interchange between oxidation states is promoted by a "Janus" ligand that isomerizes between binding modes that favor Mn3+ or Mn2+. It is the only ligand that supports stable complexes of Mn3+ and Mn2+ in biological milieu. Rapid interconversion between oxidation states is mediated by peroxidase activity (oxidation) and l-cysteine (reduction). This Janus system provides a new paradigm for the design of biochemically responsive MRI contrast agents.
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Affiliation(s)
- Eric M. Gale
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Chloe M. Jones
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Ian Ramsay
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Christian T. Farrar
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Peter Caravan
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
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Chen HH, Chen Y, Farrar CT, Gale EM, Caravan P, Liao R, Chen JW, Sosnovik DE. Molecular MRI of myocardial peroxidase activity in ischemic injury reveals a chemical milieu incompatible with stem cell survival. Journal of Cardiovascular Magnetic Resonance 2016. [PMCID: PMC5032046 DOI: 10.1186/1532-429x-18-s1-o16] [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] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
Contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used to diagnose soft tissue and vascular abnormalities. However, safety concerns limit the use of iodinated and gadolinium (Gd)-based CT and MRI contrast media in renally compromised patients. With an estimated 14% of the US population suffering from chronic kidney disease (CKD), contrast media compatible with renal impairment is sorely needed. We present the new manganese(II) complex [Mn(PyC3A)(H2O)](-) as a Gd alternative. [Mn(PyC3A)(H2O)](-) is among the most stable Mn(II) complexes at pH 7.4 (log KML = 11.40). In the presence of 25 mol equiv of Zn at pH 6.0, 37 °C, [Mn(PyC3A)(H2O)](-) is 20-fold more resistant to dissociation than [Gd(DTPA)(H2O)](2-). Relaxivity of [Mn(PyC3A)(H2O)](-) in blood plasma is comparable to commercial Gd contrast agents. Biodistribution analysis confirms that [Mn(PyC3A)(H2O)](-) clears via a mixed renal/hepatobiliary pathway with >99% elimination by 24 h. [Mn(PyC3A)(H2O)](-) was modified to form a bifunctional chelator and 4 chelates were conjugated to a fibrin-specific peptide to give Mn-FBP. Mn-FBP binds the soluble fibrin fragment DD(E) with Kd = 110 nM. Per Mn relaxivity of Mn-FBP is 4-fold greater than [Mn(PyC3A)(H2O)](-) and increases 60% in the presence of fibrin, consistent with binding. Mn-FBP provided equivalent thrombus enhancement to the state of the art Gd analogue, EP-2104R, in a rat model of arterial thrombosis. Mn metabolite analysis reveals no evidence of dechelation and the probe was >99% eliminated after 24 h. [Mn(PyC3A)(H2O)](-) is a lead development candidate for an imaging probe that is compatible with renally compromised patients.
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Affiliation(s)
- Eric M. Gale
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Iliyana P. Atanasova
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Francesco Blasi
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Ilknur Ay
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Peter Caravan
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
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Broering EP, Dillon S, Gale EM, Steiner RA, Telser J, Brunold TC, Harrop TC. Accessing Ni(III)-thiolate versus Ni(II)-thiyl bonding in a family of Ni-N2S2 synthetic models of NiSOD. Inorg Chem 2015; 54:3815-28. [PMID: 25835183 PMCID: PMC4630978 DOI: 10.1021/ic503124f] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [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: 01/29/2023]
Abstract
Superoxide dismutase (SOD) catalyzes the disproportionation of superoxide (O2(• -)) into H2O2 and O2(g) by toggling through different oxidation states of a first-row transition metal ion at its active site. Ni-containing SODs (NiSODs) are a distinct class of this family of metalloenzymes due to the unusual coordination sphere that is comprised of mixed N/S-ligands from peptide-N and cysteine-S donor atoms. A central goal of our research is to understand the factors that govern reactive oxygen species (ROS) stability of the Ni-S(Cys) bond in NiSOD utilizing a synthetic model approach. In light of the reactivity of metal-coordinated thiolates to ROS, several hypotheses have been proffered and include the coordination of His1-Nδ to the Ni(II) and Ni(III) forms of NiSOD, as well as hydrogen bonding or full protonation of a coordinated S(Cys). In this work, we present NiSOD analogues of the general formula [Ni(N2S)(SR')](-), providing a variable location (SR' = aryl thiolate) in the N2S2 basal plane coordination sphere where we have introduced o-amino and/or electron-withdrawing groups to intercept an oxidized Ni species. The synthesis, structure, and properties of the NiSOD model complexes (Et4N)[Ni(nmp)(SPh-o-NH2)] (2), (Et4N)[Ni(nmp)(SPh-o-NH2-p-CF3)] (3), (Et4N)[Ni(nmp)(SPh-p-NH2)] (4), and (Et4N)[Ni(nmp)(SPh-p-CF3)] (5) (nmp(2-) = dianion of N-(2-mercaptoethyl)picolinamide) are reported. NiSOD model complexes with amino groups positioned ortho to the aryl-S in SR' (2 and 3) afford oxidized species (2(ox) and 3(ox)) that are best described as a resonance hybrid between Ni(III)-SR and Ni(II)-(•)SR based on ultraviolet-visible (UV-vis), magnetic circular dichroism (MCD), and electron paramagnetic resonance (EPR) spectroscopies, as well as density functional theory (DFT) calculations. The results presented here, demonstrating the high percentage of S(3p) character in the highest occupied molecular orbital (HOMO) of the four-coordinate reduced form of NiSOD (NiSODred), suggest that the transition from NiSODred to the five-coordinate oxidized form of NiSOD (NiSODox) may go through a four-coordinate Ni-(•)S(Cys) (NiSODox-Hisoff) that is stabilized by coordination to Ni(II).
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Affiliation(s)
- Ellen P. Broering
- Department of Chemistry and Center for Metalloenzyme Studies, The University of Georgia, 1001 Cedar Street, Athens, Georgia 30602, United States
| | - Stephanie Dillon
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Eric M. Gale
- Department of Chemistry and Center for Metalloenzyme Studies, The University of Georgia, 1001 Cedar Street, Athens, Georgia 30602, United States
| | - Ramsey A. Steiner
- Department of Chemistry and Center for Metalloenzyme Studies, The University of Georgia, 1001 Cedar Street, Athens, Georgia 30602, United States
| | - Joshua Telser
- Department of Biological, Chemical and Physical Sciences, Roosevelt University, 430 South Michigan Avenue, Chicago, Illinois 60605, United States
| | - Thomas C. Brunold
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Todd C. Harrop
- Department of Chemistry and Center for Metalloenzyme Studies, The University of Georgia, 1001 Cedar Street, Athens, Georgia 30602, United States
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Abstract
This perspective outlines strategies towards the development of MR imaging probes that our lab has explored over the last 15 years. Namely, we discuss methods to enhance the signal generating capacity of MR probes and how to achieve tissue specificity through protein targeting or probe activation within the tissue microenvironment.
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Affiliation(s)
- Eszter Boros
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Eric M Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
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Abstract
A Mn(II) chelating dendrimer was prepared as a contrast agent for MRI applications. The dendrimer comprises six tyrosine-derived [Mn(EDTA)(H2 O)](2-) moieties coupled to a cyclotriphosphazene core. Variable temperature (17) O NMR spectroscopy revealed a single water co-ligand per Mn(II) that undergoes fast water exchange (kex =(3.0±0.1)×10(8) s(-1) at 37 °C). The 37 °C per Mn(II) relaxivity ranged from 8.2 to 3.8 mM(-1) s(-1) from 0.47 to 11.7 T, and is sixfold higher on a per molecule basis. From this field dependence a rotational correlation time was estimated as 0.45(±0.02) ns. The imaging and pharmacokinetic properties of the dendrimer were compared to clinically used [Gd(DTPA)(H2 O)](2-) in mice at 4.7 T. On first pass, the higher per ion relaxivity of the dendrimer resulted in twofold greater blood signal than for [Gd(DTPA)(H2 O)](2-) . Blood clearance was fast and elimination occurred through both the renal and hepatobiliary routes. This Mn(II) containing dendrimer represents a potential alternative to Gd-based contrast agents, especially in patients with chronic kidney disease where the use of current Gd-based agents may be contraindicated.
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Affiliation(s)
- Jiang Zhu
- Athinoula A. Martinos Center for Biomedical Imaging, Deparment of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Masachusetts, USA, 02141
- Sichuan Key Laboratory of Medical Imaging, North Sichuan Medical College
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Deparment of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Masachusetts, USA, 02141
| | - Iliyana Atanasova
- Massachusetts Institue of Technology, Cambridge, Massachusetts, USA, 02141
| | - Tyson A. Rietz
- Athinoula A. Martinos Center for Biomedical Imaging, Deparment of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Masachusetts, USA, 02141
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging, Deparment of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Masachusetts, USA, 02141
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Gale EM, Mukherjee S, Liu C, Loving GS, Caravan P. Structure-redox-relaxivity relationships for redox responsive manganese-based magnetic resonance imaging probes. Inorg Chem 2014; 53:10748-61. [PMID: 25226090 PMCID: PMC4186673 DOI: 10.1021/ic502005u] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [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: 08/20/2014] [Indexed: 12/11/2022]
Abstract
A library of 10 Mn-containing complexes capable of switching reversibly between the Mn(II) and Mn(III) oxidation states was prepared and evaluated for potential usage as MRI reporters of tissue redox activity. We synthesized N-(2-hydroxybenzyl)-N,N',N'-ethylenediaminetriacetic acid (HBET) and N-(2-hydroxybenzyl-N,N',N'-trans-1,2-cyclohexylenediaminetriacetic acid (CyHBET) ligands functionalized (-H, -OMe, -NO2) at the 5-position of the aromatic ring. The Mn(II) complexes of all ligands and the Mn(III) complexes of the 5-H and 5-NO2 functionalized ligands were synthesized and isolated, but the Mn(III) complexes with the 5-OMe functionalized ligands were unstable. (1)H relaxivity of the 10 isolable complexes was measured at pH 7.4 and 37 °C, 1.4 T. Thermodynamic stability, pH-dependent complex speciation, hydration state, water exchange kinetics of the Mn(II) complexes, and pseudo-first order reduction kinetics of the Mn(III) complexes were studied using a combination of pH-potentiometry, UV-vis spectroscopy, and (1)H and (17)O NMR measurements. The effects of ligand structural and electronic modifications on the Mn(II/III) redox couple were studied by cyclic voltammetry. The Mn(II) complexes are potent relaxation agents as compared to the corresponding Mn(III) species with [Mn(II)(CyHBET)(H2O)](2-) exhibiting a 7.5-fold higher relaxivity (3.3 mM(-1) s(-1)) than the oxidized form (0.4 mM(-1) s(-1)). At pH 7.4, Mn(II) exists as a mixture of fully deprotonated (ML) and monoprotonated (HML) complexes and Mn(II) complex stability decreases as the ligands become more electron-releasing (pMn for 10 μM [Mn(II)(CyHBET-R')(H2O)](2-) decreases from 7.6 to 6.2 as R' goes from -NO2 to -OMe, respectively). HML speciation increases as the electron-releasing nature of the phenolato-O donor increases. The presence of a water coligand is maintained upon conversion from HML to ML, but the water exchange rate of ML is faster by up to 2 orders of magnitude (k(ex)(310) for H[Mn(II)(CyHBET)(H2O)](-) and [Mn(II)(CyHBET)(H2O)](2-) are 1.2 × 10(8) and 1.0 × 10(10) s(-1), respectively). The Mn(II/III) redox potential can be tuned over a range of 0.30 V (E(1/2) = 0.27-0.57 V) through electronic modifications to the 5-substituent of the aromatic ligand component. However, care must be taken in tuning the ligand electronics to avoid Mn(III)-ligand autoredox. Taken together, these results serve to establish criteria for optimizing Mn(III) versus Mn(II) relaxivity differentials, complex stability, and Mn(II/III) redox potential.
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Affiliation(s)
| | | | - Cynthia Liu
- The Athinoula
A. Martinos Center for Biomedical Imaging, Department of Radiology,
Massachusetts General Hospital, Harvard
Medical School, 149 Thirteenth
Street, Suite 2301, Charlestown, Massachusetts 02129, United States
| | - Galen S. Loving
- The Athinoula
A. Martinos Center for Biomedical Imaging, Department of Radiology,
Massachusetts General Hospital, Harvard
Medical School, 149 Thirteenth
Street, Suite 2301, Charlestown, Massachusetts 02129, United States
| | - Peter Caravan
- The Athinoula
A. Martinos Center for Biomedical Imaging, Department of Radiology,
Massachusetts General Hospital, Harvard
Medical School, 149 Thirteenth
Street, Suite 2301, Charlestown, Massachusetts 02129, United States
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Gale EM, Zhu J, Caravan P. Direct measurement of the Mn(II) hydration state in metal complexes and metalloproteins through 17O NMR line widths. J Am Chem Soc 2013; 135:18600-8. [PMID: 24088013 DOI: 10.1021/ja4094132] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Here we describe a simple method to estimate the inner-sphere hydration state of the Mn(II) ion in coordination complexes and metalloproteins. The line width of bulk H2(17)O is measured in the presence and absence of Mn(II) as a function of temperature, and transverse (17)O relaxivities are calculated. It is demonstrated that the maximum (17)O relaxivity is directly proportional to the number of inner-sphere water ligands (q). Using a combination of literature data and experimental data for 12 Mn(II) complexes, we show that this method provides accurate estimates of q with an uncertainty of ±0.2 water molecules. The method can be implemented on commercial NMR spectrometers working at fields of 7 T and higher. The hydration number can be obtained for micromolar Mn(II) concentrations. We show that the technique can be extended to metalloproteins or complex:protein interactions. For example, Mn(II) binds to the multimetal binding site A on human serum albumin with two inner-sphere water ligands that undergo rapid exchange (1.06 × 10(8) s(-1) at 37 °C). The possibility of extending this technique to other metal ions such as Gd(III) is discussed.
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Affiliation(s)
- Eric M Gale
- The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital , Harvard Medical School , 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
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Abstract
We report the synthesis and MR relevant properties of CyPic3A, a heptadentate chelator that forms ternary Gd(III) complexes of hydration state q = 2. [Gd(CyPic3A)(H2O)2](-) affords an r1 value of 5.70 mM(-1) s(-1) at 1.41 T and 310 K and displays thermodynamic stability and kinetic inertness comparable to FDA approved MR imaging probes.
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Affiliation(s)
- Eric M Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
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Broering EP, Truong PT, Gale EM, Harrop TC. Synthetic Analogues of Nickel Superoxide Dismutase: A New Role for Nickel in Biology. Biochemistry 2012; 52:4-18. [DOI: 10.1021/bi3014533] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ellen P. Broering
- Department
of Chemistry and Center for Metalloenzyme
Studies, The University of Georgia, 1001
Cedar Street, Athens, Georgia 30602, United States
| | - Phan T. Truong
- Department
of Chemistry and Center for Metalloenzyme
Studies, The University of Georgia, 1001
Cedar Street, Athens, Georgia 30602, United States
| | - Eric M. Gale
- Department
of Chemistry and Center for Metalloenzyme
Studies, The University of Georgia, 1001
Cedar Street, Athens, Georgia 30602, United States
| | - Todd C. Harrop
- Department
of Chemistry and Center for Metalloenzyme
Studies, The University of Georgia, 1001
Cedar Street, Athens, Georgia 30602, United States
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Gale EM, Cowart DM, Scott RA, Harrop TC. Dipeptide-based models of nickel superoxide dismutase: solvent effects highlight a critical role to Ni-S bonding and active site stabilization. Inorg Chem 2011; 50:10460-71. [PMID: 21932766 PMCID: PMC3561719 DOI: 10.1021/ic2016462] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [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: 11/30/2022]
Abstract
Nickel superoxide dismutase (Ni-SOD) catalyzes the disproportionation of the superoxide radical to O(2) and H(2)O(2) utilizing the Ni(III/II) redox couple. The Ni center in Ni-SOD resides in an unusual coordination environment that is distinct from other SODs. In the reduced state (Ni-SOD(red)), Ni(II) is ligated to a primary amine-N from His1, anionic carboxamido-N/thiolato-S from Cys2, and a second thiolato-S from Cys6 to complete a NiN(2)S(2) square-planar coordination motif. Utilizing the dipeptide N(2)S(2-) ligand, H(2)N-Gly-l-Cys-OMe (GC-OMeH(2)), an accurate model of the structural and electronic contributions provided by His1 and Cys2 in Ni-SOD(red), we constructed the dinuclear sulfur-bridged metallosynthon, [Ni(2)(GC-OMe)(2)] (1). From 1 we prepared the following monomeric Ni(II)-N(2)S(2) complexes: K[Ni(GC-OMe)(SC(6)H(4)-p-Cl)] (2), K[Ni(GC-OMe)(S(t)Bu)] (3), K[Ni(GC-OMe)(SC(6)H(4)-p-OMe)] (4), and K[Ni(GC-OMe)(SNAc)] (5). The design strategy in utilizing GC-OMe(2-) is analogous to one which we reported before (see Inorg. Chem. 2009, 48, 5620 and Inorg. Chem. 2010, 49, 7080) where Ni-SOD(red) active site mimics can be assembled at will with electronically variant RS(-) ligands. Discussed herein is our initial account pertaining to the aqueous behavior of isolable, small-molecule Ni-SOD model complexes (non-maquette based). Spectroscopic (FTIR, UV-vis, ESI-MS, XAS) and electrochemical (CV) measurements suggest that 2-5 successfully simulate many of the electronic features of Ni-SOD(red). Furthermore, the aqueous studies reveal a dynamic behavior with regard to RS(-) lability and bridging interactions, suggesting a stabilizing role brought about by the protein architecture.
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Affiliation(s)
- Eric M. Gale
- Department of Chemistry, University of Georgia, 1001 Cedar Street, Athens, Georgia 30602
| | - Darin M. Cowart
- Department of Chemistry, University of Georgia, 1001 Cedar Street, Athens, Georgia 30602
| | - Robert A. Scott
- Department of Chemistry, University of Georgia, 1001 Cedar Street, Athens, Georgia 30602
| | - Todd C. Harrop
- Department of Chemistry, University of Georgia, 1001 Cedar Street, Athens, Georgia 30602
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Gale EM, Simmonett AC, Telser J, Schaefer HF, Harrop TC. Toward Functional Ni-SOD Biomimetics: Achieving a Structural/Electronic Correlation with Redox Dynamics. Inorg Chem 2011; 50:9216-8. [DOI: 10.1021/ic201822f] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Eric M. Gale
- Department of Chemistry and Center for Computational Chemistry, The University of Georgia, 1001 Cedar Street, Athens, Georgia 30602, United States
| | - Andrew C. Simmonett
- Department of Chemistry and Center for Computational Chemistry, The University of Georgia, 1001 Cedar Street, Athens, Georgia 30602, United States
| | - Joshua Telser
- Department of Biological, Chemical and Physical Sciences, Roosevelt University, 430 South Michigan Avenue, Chicago, Illinois 60605, United States
| | - Henry F. Schaefer
- Department of Chemistry and Center for Computational Chemistry, The University of Georgia, 1001 Cedar Street, Athens, Georgia 30602, United States
| | - Todd C. Harrop
- Department of Chemistry and Center for Computational Chemistry, The University of Georgia, 1001 Cedar Street, Athens, Georgia 30602, United States
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Gale EM, Patra AK, Harrop TC. Versatile methodology toward NiN(2)S(2) complexes as nickel superoxide dismutase models: structure and proton affinity. Inorg Chem 2010; 48:5620-2. [PMID: 20507097 DOI: 10.1021/ic9009042] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Structural features of the reduced form of the nickel superoxide dismutase (Ni-SOD) active site have been modeled with asymmetric NiN(2)S(2) complexes (Et(4)N)[Ni(nmp)(SR)] (R = C(6)H(4)-p-Cl (2) and (S(t)Bu) (3)) obtained via S,S-bridge splitting of the dimeric metallosynthon, [Ni(2)(nmp)(2)] (1). Complexes 2 and 3 are irreversibly oxidized at potentials within the window needed for SOD activity, 236 and 75 mV versus Ag/AgCl, respectively. The exogenous thiolato-S in 2 and 3 serves as a proton acceptor, suggesting potential involvement of Cys6 in Ni-SOD for H(+) storage between SOD half reactions.
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Affiliation(s)
- Eric M Gale
- Department of Chemistry, University of Georgia, 1001 Cedar St, Athens, Georgia 30602, USA
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Gale EM, Narendrapurapu BS, Simmonett AC, Schaefer HF, Harrop TC. Exploring the Effects of H-Bonding in Synthetic Analogues of Nickel Superoxide Dismutase (Ni-SOD): Experimental and Theoretical Implications for Protection of the Ni−SCys Bond. Inorg Chem 2010; 49:7080-96. [DOI: 10.1021/ic1009187] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Eric M. Gale
- Department of Chemistry and Center for Computational Chemistry, University of Georgia, 1001 Cedar Street, Athens, Georgia 30602
| | - Beulah S. Narendrapurapu
- Department of Chemistry and Center for Computational Chemistry, University of Georgia, 1001 Cedar Street, Athens, Georgia 30602
| | - Andrew C. Simmonett
- Department of Chemistry and Center for Computational Chemistry, University of Georgia, 1001 Cedar Street, Athens, Georgia 30602
| | - Henry F. Schaefer
- Department of Chemistry and Center for Computational Chemistry, University of Georgia, 1001 Cedar Street, Athens, Georgia 30602
| | - Todd C. Harrop
- Department of Chemistry and Center for Computational Chemistry, University of Georgia, 1001 Cedar Street, Athens, Georgia 30602
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Bottazzo GF, Todd I, Schwarz G, Gale EM, Pujol-Borrell R. On the pathogenesis of human type I diabetes: where do we stand? Ann Inst Pasteur Immunol 1987; 138:117-23. [PMID: 3555538 DOI: 10.1016/s0769-2625(87)80100-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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