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Imaging of Alkaline Phosphatase Activity in Bone Tissue

The purpose of this study was to develop a paradigm for quantitative molecular imaging of bone cell activity. We hypothesized the feasibility of non-invasive imaging of the osteoblast enzyme alkaline phosphatase (ALP) using a small imaging molecule in combination with (19)Flourine magnetic resonance...

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Autores principales: Gade, Terence P., Motley, Matthew W., Beattie, Bradley J., Bhakta, Roshni, Boskey, Adele L., Koutcher, Jason A., Mayer-Kuckuk, Philipp
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3143164/
https://www.ncbi.nlm.nih.gov/pubmed/21799916
http://dx.doi.org/10.1371/journal.pone.0022608
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author Gade, Terence P.
Motley, Matthew W.
Beattie, Bradley J.
Bhakta, Roshni
Boskey, Adele L.
Koutcher, Jason A.
Mayer-Kuckuk, Philipp
author_facet Gade, Terence P.
Motley, Matthew W.
Beattie, Bradley J.
Bhakta, Roshni
Boskey, Adele L.
Koutcher, Jason A.
Mayer-Kuckuk, Philipp
author_sort Gade, Terence P.
collection PubMed
description The purpose of this study was to develop a paradigm for quantitative molecular imaging of bone cell activity. We hypothesized the feasibility of non-invasive imaging of the osteoblast enzyme alkaline phosphatase (ALP) using a small imaging molecule in combination with (19)Flourine magnetic resonance spectroscopic imaging ((19)FMRSI). 6, 8-difluoro-4-methylumbelliferyl phosphate (DiFMUP), a fluorinated ALP substrate that is activatable to a fluorescent hydrolysis product was utilized as a prototype small imaging molecule. The molecular structure of DiFMUP includes two Fluorine atoms adjacent to a phosphate group allowing it and its hydrolysis product to be distinguished using (19)Fluorine magnetic resonance spectroscopy ((19)FMRS) and (19)FMRSI. ALP-mediated hydrolysis of DiFMUP was tested on osteoblastic cells and bone tissue, using serial measurements of fluorescence activity. Extracellular activation of DiFMUP on ALP-positive mouse bone precursor cells was observed. Concurringly, DiFMUP was also activated on bone derived from rat tibia. Marked inhibition of the cell and tissue activation of DiFMUP was detected after the addition of the ALP inhibitor levamisole. (19)FMRS and (19)FMRSI were applied for the non-invasive measurement of DiFMUP hydrolysis. (19)FMRS revealed a two-peak spectrum representing DiFMUP with an associated chemical shift for the hydrolysis product. Activation of DiFMUP by ALP yielded a characteristic pharmacokinetic profile, which was quantifiable using non-localized (19)FMRS and enabled the development of a pharmacokinetic model of ALP activity. Application of (19)FMRSI facilitated anatomically accurate, non-invasive imaging of ALP concentration and activity in rat bone. Thus, (19)FMRSI represents a promising approach for the quantitative imaging of bone cell activity during bone formation with potential for both preclinical and clinical applications.
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spelling pubmed-31431642011-07-28 Imaging of Alkaline Phosphatase Activity in Bone Tissue Gade, Terence P. Motley, Matthew W. Beattie, Bradley J. Bhakta, Roshni Boskey, Adele L. Koutcher, Jason A. Mayer-Kuckuk, Philipp PLoS One Research Article The purpose of this study was to develop a paradigm for quantitative molecular imaging of bone cell activity. We hypothesized the feasibility of non-invasive imaging of the osteoblast enzyme alkaline phosphatase (ALP) using a small imaging molecule in combination with (19)Flourine magnetic resonance spectroscopic imaging ((19)FMRSI). 6, 8-difluoro-4-methylumbelliferyl phosphate (DiFMUP), a fluorinated ALP substrate that is activatable to a fluorescent hydrolysis product was utilized as a prototype small imaging molecule. The molecular structure of DiFMUP includes two Fluorine atoms adjacent to a phosphate group allowing it and its hydrolysis product to be distinguished using (19)Fluorine magnetic resonance spectroscopy ((19)FMRS) and (19)FMRSI. ALP-mediated hydrolysis of DiFMUP was tested on osteoblastic cells and bone tissue, using serial measurements of fluorescence activity. Extracellular activation of DiFMUP on ALP-positive mouse bone precursor cells was observed. Concurringly, DiFMUP was also activated on bone derived from rat tibia. Marked inhibition of the cell and tissue activation of DiFMUP was detected after the addition of the ALP inhibitor levamisole. (19)FMRS and (19)FMRSI were applied for the non-invasive measurement of DiFMUP hydrolysis. (19)FMRS revealed a two-peak spectrum representing DiFMUP with an associated chemical shift for the hydrolysis product. Activation of DiFMUP by ALP yielded a characteristic pharmacokinetic profile, which was quantifiable using non-localized (19)FMRS and enabled the development of a pharmacokinetic model of ALP activity. Application of (19)FMRSI facilitated anatomically accurate, non-invasive imaging of ALP concentration and activity in rat bone. Thus, (19)FMRSI represents a promising approach for the quantitative imaging of bone cell activity during bone formation with potential for both preclinical and clinical applications. Public Library of Science 2011-07-25 /pmc/articles/PMC3143164/ /pubmed/21799916 http://dx.doi.org/10.1371/journal.pone.0022608 Text en Gade et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Gade, Terence P.
Motley, Matthew W.
Beattie, Bradley J.
Bhakta, Roshni
Boskey, Adele L.
Koutcher, Jason A.
Mayer-Kuckuk, Philipp
Imaging of Alkaline Phosphatase Activity in Bone Tissue
title Imaging of Alkaline Phosphatase Activity in Bone Tissue
title_full Imaging of Alkaline Phosphatase Activity in Bone Tissue
title_fullStr Imaging of Alkaline Phosphatase Activity in Bone Tissue
title_full_unstemmed Imaging of Alkaline Phosphatase Activity in Bone Tissue
title_short Imaging of Alkaline Phosphatase Activity in Bone Tissue
title_sort imaging of alkaline phosphatase activity in bone tissue
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3143164/
https://www.ncbi.nlm.nih.gov/pubmed/21799916
http://dx.doi.org/10.1371/journal.pone.0022608
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