Abstract
Imaging targeting vesicular monoamine transporter (VMAT2) alterations is a sensitive tool for early diagnosis of Parkinson’s disease. Our group has reported several novel 2-amino-DTBZ derivatives as potential VMAT2 imaging agents. The objective of this paper is to develop a non-radiolabeled methodology to screen the candidate compounds for accelerating the drug discovery process. 9-[18F]fluoropropyl-(+)-dihydrotetrabenazine ([18F]AV-133) is a PET imaging agent targeting VMAT2 binding sites in the brain. Nonradioactive AV-133 was injected (iv) into rats, at the end of the allotted time, the animals were killed and six regions of brain and plasma from each animal were processed for quantitative measurement of AV-133 by LC-MS/MS. These data were converted to the percentage injected dose per gram tissue weight (%ID/g tissue) and the brain target tissue to background ratios to allow direct comparison with data obtained by gamma counting of the injected radioactive [18F]AV-133. The %ID/g and the brain target tissue to background ratios calculated using the LC-MS/MS method were highly correlated to the values obtained by standard radioactivity measurements of [18F]AV-133. The pattern of AV-133 in rat brain was consistent with the known distribution of VMAT2. The concordance indicated that high-sensitivity LC-MS/MS is an indispensable tool in evaluating the quantity of administered chemical in tissue as part of the development of new molecular imaging probes. Furthermore, several novel 2-amino-DTBZ derivatives were detected using this methodology, and their biodistribution data in rat brain were obtained. The information about target engagements of candidates was provided.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Frey KA, Koeppe RA, Kilbourn MR. Imaging the vesicular monoamine transporter. Adv Neurol. 2001;86:237–47.
Miller GW, Wang YM, Gainetdinov RR, Caron MG. Dopamine transporter and vesicular monoamine transporter knockout mice: implications for Parkinson’s disease. Methods Mol Med. 2001;62:179–90.
Brooks DJ, Frey KA, Marek KL, Oakes D, Paty D, Prentice R, et al. Assessment of neuroimaging techniques as biomarkers of the progression of Parkinson’s disease. Exp Neurol. 2003;184:S68–79.
Okamura N, Villemagne VL, Drago J, Pejoska S, Dhamija RK, Mulligan RS, et al. In vivo measurement of vesicular monoamine transporter type 2 density in Parkinson disease with (18)F-AV-133. J Nucl Med. 2010;51:223–8.
Schafer MK, Weihe E, Eiden LE. Localization and expression of VMAT2 across mammalian species: a translational guide for its visualization and targeting in health and disease. Adv Pharmacol. 2013;68:319–34.
Schafer MK, Hartwig NR, Kalmbach N, Klietz M, Anlauf M, Eiden LE, et al. Species-specific vesicular monoamine transporter 2 (VMAT2) expression in mammalian pancreatic beta cells: implications for optimising radioligand-based human beta cell mass (BCM) imaging in animal models. Diabetologia. 2013;56:1047–56.
Zhu L, Plössl K, Kung HK. Expanding the scope of Fluorine tags for PET imaging. Science. 2013;342:429–30.
Okamura N, Villemagne VL, Drago J, Pejoska S, Dhamija RK, Mulligan RS, et al. In vivo measurement of vesicular monoamine transporter type 2 density in Parkinson disease with (18)F-AV-133. J Nucl Med. 2010;51:223–8.
Kung MP, Hou C, Goswami R, Ponde DE, Kilbourn MR, Kung HF. Characterization of optically resolved 9-fluoropropyl-dihydrotetrabenazine as a potential PET imaging agent targeting vesicular monoamine transporters. Nucl Med Biol. 2007;34:239–46.
Zhu L, Liu J, Kung HF. Synthesis and evaluation of 2-amino-dihydrotetrabenzine derivatives as probes for imaging vesicular monoamine transporter-2. Bioorg Med Chem Lett. 2009;19:5026–8.
Du J, Zhu L, Zhou X, Yin W, Deng A, Qiao J. Dose–response relationships of FMISO between trace dose and various macro-doses in rat by ultra-performance liquid chromatography with mass spectrometry and radioactivity analysis. J Pharm Biomed Anal. 2012;70:499–504.
Barth VN, Chernet E, Martin LJ, Need AB, Rash KS, Morin M, et al. Comparison of rat dopamine D2 receptor occupancy for a series of antipsychotic drugs measured using radio labeled or nonlabeled raclopride tracer. Life Sci. 2006;78:3007–12.
Chernet E, Martin LJ, Li D, Need AB, Barth VN, Rash KS, et al. Use of LC/MS to assess brain tracer distribution in preclinical, in vivo receptor occupancy studies: dopamine D2, serotonin 2A and NK-1 receptors as examples. Life Sci. 2005;78:340–6.
Need AB, McKinzie JH, Mitch CH, Statnick MA, Phebus LA. In vivo rat brain opioid receptor binding of LY255582 assessed with a novel method using LC/MS/MS and the administration of three tracers simultaneously. Life Sci. 2007;81:1389–96.
Nirogi R, Kandikere V, Bhyrapuneni G, Muddana N, Saralaya R, Ponnamaneni RK, et al. In vivo receptor occupancy assay of histamine H3 receptor antagonist in rats using non-radiolabeled tracer. J Pharmacol Toxicol Methods. 2012;65:115–21.
Nirogi R, Kandikere V, Bhyrapuneni G, Saralaya R, Muddana N, Komarneni P. Methyllycaconitine: a non-radiolabeled ligand for mapping α7 neuronal nicotinic acetylcholine receptors—in vivo target localization and biodistribution in rat brain. J Pharmacol Toxicol Methods. 2012;66:22–8.
Nirogi R, Kandikere V, Bhyrapuneni G, Saralaya R, Ajjala DR, Aleti RR, et al. In-vivo rat striatal 5-HT4 receptor occupancy using non-radiolabelled SB207145. J Pharm Pharmacol. 2013;65:704–12.
Zhou X, Qiao J, Yin W, Zhu L, Kung H. Determination of the penetration of 9-fluoropropyl-(+)-dihydrotetrabenazine across the blood–brain barrier in rats by microdialysis combined with liquid chromatography-tandem mass spectrometry. J Chromatogr B Anal Technol Biomed Life Sci. 2011;879:3041–6.
Zhou X, Qiao J, Yin W, Zhu L, Kung HF. Study the effect of a pseudo-carrier on pharmacokinetics of 9-fluoropropyl-(+)-dihydrotetrabenazine in rat plasma by ultra-performance liquid chromatography-tandem mass spectrometry. J Chromatogr B Anal Technol Biomed Life Sci. 2011;879:505–10.
Kung MP, Hou C, Goswami R, Ponde DE, Kilbourn MR, Kung HF. Characterization of optically resolved 9-fluoropropyl-dihydrotetrabenazine as a potential PET imaging agent targeting vesicular monoamine transporters. Nucl Med Biol. 2007;34:239–46.
USFDA, 2001, http://www.fda.gov/cder/guidance/4252fnl.pdf.
Kilbourn MR, Hockley B, Lee L, Hou C, Goswami R, Ponde DE, et al. Pharmacokinetics of [(18)F]fluoroalkyl derivatives of dihydrotetrabenazine in rat and monkey brain. Nucl Med Biol. 2007;34:233–7.
Acknowledgments
This work was financially supported by the National 973 Program (2011CB504105), the National 863 Program (SS2012AA020831), the Open Foundation of the Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing Capital Medical University, and BIBD-PXM2013_014226_07_000084. The authors appreciate Professor Hank F. Kung (Department of Radiology, University of Pennsylvania, USA) for his helpful suggestions and comments.
Author information
Authors and Affiliations
Corresponding authors
Rights and permissions
About this article
Cite this article
Deng, A., Wu, X., Zhou, X. et al. Mapping the Target Localization and Biodistribution of Non-Radiolabeled VMAT2 Ligands in rat Brain. AAPS J 16, 592–599 (2014). https://doi.org/10.1208/s12248-014-9584-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1208/s12248-014-9584-9