Preparation and First Preclinical Evaluation of [(18)F]FE@SNAP: A Potential PET Tracer for the Melanin-Concentrating Hormone Receptor-1 (MCHR1)
Overview
Authors
Affiliations
The melanin-concentrating hormone (MCH) system is a new target for the treatment of human disorders. Since the knowledge of the MCH system's involvement in a variety of pathologies (obesity, diabetes, and deregulation of metabolic feedback mechanism) is based on in vitro or preclinical studies, a suitable positron emission tomography (PET) tracer needs to be developed. We herein present the preparation and first preclinical evaluation of [(18)F]FE@SNAP - a new PET tracer for MCH receptor-1 (MCHR1). The synthesis was performed using a microfluidic device. Preclinical evaluation included binding affinity, plasma stability, plasma free fraction, stability against the cytochrome P-450 (CYP450) system using liver microsomes, stability against carboxyl-esterase, and methods to assess the penetration of the blood-brain barrier (BBB) such as logD analysis and immobilized artificial membrane (IAM) chromatography. Levels at 374 ± 202 MBq [(18)F]FE@SNAP were obtained after purification. The obtained K d value of [(18)F]FE@SNAP was 2.9 nM. [(18)F]FE@SNAP evinced high stability against carboxylesterase, CYP450 enzymes, and in human plasma. LogD (3.83) and IAM chromatography results (Pm=0.51) were in the same range as for known BBB-penetrating compounds. The synthesis of [(18)F]FE@SNAP was reliable and successful. Due to high binding affinity and stability, [(18)F]FE@SNAP is a promising tracer for MCHR1.
The historical progression of positron emission tomography research in neuroendocrinology.
Bini J Front Neuroendocrinol. 2023; 70:101081.
PMID: 37423505 PMC: 10530506. DOI: 10.1016/j.yfrne.2023.101081.
Discovery of melanin-concentrating hormone receptor 1 in brown adipose tissue.
Philippe C, Klebermass E, Balber T, Kulterer O, Zeilinger M, Egger G Ann N Y Acad Sci. 2021; 1494(1):70-86.
PMID: 33502798 PMC: 8248337. DOI: 10.1111/nyas.14563.
Shaw R, Tamagnan G, Tavares A Front Neurosci. 2020; 14:871.
PMID: 33117115 PMC: 7559529. DOI: 10.3389/fnins.2020.00871.
Radiopharmaceutical Evidence for MCHR1 Binding Sites in Murine Brown Adipocytes.
Balber T, Bencurova K, Kiefer F, Kulterer O, Klebermass E, Egger G Front Endocrinol (Lausanne). 2019; 10:324.
PMID: 31244769 PMC: 6581027. DOI: 10.3389/fendo.2019.00324.
SNAPshots of the MCHR1: a Comparison Between the PET-Tracers [F]FE@SNAP and [C]SNAP-7941.
Philippe C, Zeilinger M, Dumanic M, Pichler F, Fetty L, Vraka C Mol Imaging Biol. 2018; 21(2):257-268.
PMID: 29948643 PMC: 6449294. DOI: 10.1007/s11307-018-1212-0.