» Articles » PMID: 24900410

Evaluation of [(11)C]N-Methyl Lansoprazole As a Radiopharmaceutical for PET Imaging of Tau Neurofibrillary Tangles

Overview
Specialty Chemistry
Date 2014 Jun 6
PMID 24900410
Citations 21
Authors
Affiliations
Soon will be listed here.
Abstract

[(11)C]N-Methyl lansoprazole ([(11)C]NML, 3) was synthesized and evaluated as a radiopharmaceutical for quantifying tau neurofibrillary tangle (NFT) burden using positron emission tomography (PET) imaging. [(11)C]NML was synthesized from commercially available lansoprazole in 4.6% radiochemical yield (noncorrected RCY, based upon [(11)C]MeI), 99% radiochemical purity, and 16095 Ci/mmol specific activity (n = 5). Log P was determined to be 2.18. A lack of brain uptake in rodent microPET imaging revealed [(11)C]NML to be a substrate for the rodent permeability-glycoprotein 1 (PGP) transporter, but this could be overcome by pretreating with cyclosporin A to block the PGP. Contrastingly, [(11)C]NML was not found to be a substrate for the primate PGP, and microPET imaging in rhesus revealed [(11)C]NML uptake in the healthy primate brain of ∼1600 nCi/cc maximum at 3 min followed by rapid egress to 500 nCi/cc. Comparative autoradiography between wild-type rats and transgenic rats expressing human tau (hTau +/+) revealed 12% higher uptake of [(11)C]NML in the cortex of brains expressing human tau. Further autoradiography with tau positive brain samples from progressive supranuclear palsy (PSP) patients revealed colocalization of [(11)C]NML with tau NFTs identified using modified Bielschowsky staining. Finally, saturation binding experiments with heparin-induced tau confirmed K d and Bmax values of [(11)C]NML as 700 pM and 0.214 fmol/μg, respectively.

Citing Articles

Strategies of positron emission tomography (PET) tracer development for imaging of tau and α-synuclein in neurodegenerative disorders.

Mekala S, Wu Y, Li Y RSC Med Chem. 2024; .

PMID: 39678127 PMC: 11638850. DOI: 10.1039/d4md00576g.


The Sensitivity of Tau Tracers for the Discrimination of Alzheimer's Disease Patients and Healthy Controls by PET.

Mohammadi Z, Alizadeh H, Marton J, Cumming P Biomolecules. 2023; 13(2).

PMID: 36830659 PMC: 9953528. DOI: 10.3390/biom13020290.


Positron Emission Tomography in Animal Models of Tauopathies.

Cao L, Kong Y, Ji B, Ren Y, Guan Y, Ni R Front Aging Neurosci. 2022; 13:761913.

PMID: 35082657 PMC: 8784812. DOI: 10.3389/fnagi.2021.761913.


Molecular Imaging of Fluorinated Probes for Tau Protein and Amyloid-β Detection.

Yeo S, Shepelytskyi Y, Grynko V, Albert M Molecules. 2020; 25(15).

PMID: 32731418 PMC: 7435578. DOI: 10.3390/molecules25153413.


Evaluation of [F]--Methyl lansoprazole as a Tau PET Imaging Agent in First-in-Human Studies.

Kramer V, Brooks A, Haeger A, Kuljis R, Rafique W, Koeppe R ACS Chem Neurosci. 2020; 11(3):427-435.

PMID: 31898886 PMC: 7035908. DOI: 10.1021/acschemneuro.9b00639.


References
1.
Giannakopoulos P, Herrmann F, Bussiere T, Bouras C, Kovari E, Perl D . Tangle and neuron numbers, but not amyloid load, predict cognitive status in Alzheimer's disease. Neurology. 2003; 60(9):1495-500. DOI: 10.1212/01.wnl.0000063311.58879.01. View

2.
Nordberg A . PET imaging of amyloid in Alzheimer's disease. Lancet Neurol. 2004; 3(9):519-27. DOI: 10.1016/S1474-4422(04)00853-1. View

3.
Wolk D, Grachev I, Buckley C, Kazi H, Grady M, Trojanowski J . Association between in vivo fluorine 18-labeled flutemetamol amyloid positron emission tomography imaging and in vivo cerebral cortical histopathology. Arch Neurol. 2011; 68(11):1398-403. PMC: 4532383. DOI: 10.1001/archneurol.2011.153. View

4.
Herholz K, Ebmeier K . Clinical amyloid imaging in Alzheimer's disease. Lancet Neurol. 2011; 10(7):667-70. DOI: 10.1016/S1474-4422(11)70123-5. View

5.
Pearce R, Rodrigues A, Goldstein J, Parkinson A . Identification of the human P450 enzymes involved in lansoprazole metabolism. J Pharmacol Exp Ther. 1996; 277(2):805-16. View