Development of 11C-Labeled ASEM Analogues for the Detection of Neuronal Nicotinic Acetylcholine Receptors (α7-nAChR) Show others and affiliations
2022 (English) In: ACS Chemical Neuroscience, E-ISSN 1948-7193, Vol. 13, no 3, p. 352-362Article in journal (Refereed) Published
Abstract [en]
The homo-pentameric alpha 7 receptor is one of the major types of neuronal nicotinic acetylcholine receptors (α7-nAChRs) related to cognition, memory formation, and attention processing. The mapping of α7-nAChRs by PET pulls a lot of attention to realize the mechanism and development of CNS diseases such as AD, PD, and schizophrenia. Several PET radioligands have been explored for the detection of the α7-nAChR. 18F-ASEM is the most functional for in vivo quantification of α7-nAChRs in the human brain. The first aim of this study was to initially use results from in silico and machine learning techniques to prescreen and predict the binding energy and other properties of ASEM analogues and to interpret these properties in terms of atomic structures using 18F-ASEM as a lead structure, and second, to label some selected candidates with carbon-11/hydrogen-3 (11C/3H) and to evaluate the binding properties in vitro and in vivo using the labeled candidates. In silico predictions are obtained from perturbation free-energy calculations preceded by molecular docking, molecular dynamics, and metadynamics simulations. Machine learning techniques have been applied for the BBB and P-gp-binding properties. Six analogues of ASEM were labeled with 11C, and three of them were additionally labeled with 3H. Binding properties were further evaluated using autoradiography (ARG) and PET measurements in non-human primates (NHPs). Radiometabolites were measured in NHP plasma. All six compounds were successfully synthesized. Evaluation with ARG showed that 11C-Kln83 was preferably binding to the α7-nAChR. Competition studies showed that 80% of the total binding was displaced. Further ARG studies using 3H-KIn-83 replicated the preliminary results. In the NHP PET study, the distribution pattern of 11C-KIn-83 was similar to other α7 nAChR PET tracers. The brain uptake was relatively low and increased by the administration of tariquidar, indicating a substrate of P-gp. The ASEM blocking study showed that 11C-KIn-83 specifically binds to α7 nAChRs. Preliminary in vitro evaluation of KIn-83 by ARG with both 11C and 3H and in vivo evaluation in NHP showed favorable properties for selectively imaging α7-nAChRs, despite a relatively low brain uptake.
Place, publisher, year, edition, pages American Chemical Society (ACS) , 2022. Vol. 13, no 3, p. 352-362
Keywords [en]
autoradiography, in vitro, in vivo, non-human primate, PET, radiometabolites, α7-nAChR, ABC transporter subfamily B, alpha bungarotoxin i 125, asem c 11, asem f 18, bungarotoxin receptor, carbon 11, ketamine, kin 74 c 11, kin 74 h 3, kin 75 c 11, kin 77 c 11, kin 83 c 11, kin 84 c 11, kin 85 c 11, kln83 c 11, multidrug resistance protein 1, nicotinic receptor, radioligand, radiopharmaceutical agent, tariquidar, tritium, unclassified drug, azabicyclo derivative, sulfoxide, animal experiment, animal model, animal tissue, Article, autopsy, binding affinity, blood brain barrier, calculation, clinical evaluation, computer model, controlled study, drug screening, drug structure, drug uptake, female, human, human tissue, in vitro study, in vivo study, machine learning, male, molecular docking, molecular dynamics, mouse, nerve cell, nonhuman, positron emission tomography, primate, radioactivity, radiochemistry, radiolabeling, rat, structure analysis, animal, chemistry, metabolism, procedures, alpha7 Nicotinic Acetylcholine Receptor, Animals, Azabicyclo Compounds, Cyclic S-Oxides, Molecular Docking Simulation, Positron-Emission Tomography, Receptors, Nicotinic
National Category
Pharmacology and Toxicology Medical and Health Sciences
Identifiers URN: urn:nbn:se:kth:diva-319608 DOI: 10.1021/acschemneuro.1c00730 ISI: 000743728000001 PubMedID: 35020351 Scopus ID: 2-s2.0-85123378495 OAI: oai:DiVA.org:kth-319608 DiVA, id: diva2:1701317
Note QC 20221005
2022-10-052022-10-052023-08-28 Bibliographically approved