SCIENTIFIC HUB

Follow the evidence.

SCIENTIFIC LITERATURE · MED

Development of Pyridothiophene Compounds for PET Imaging of α-Synuclein.

Chemistry · 2024-03-08

DOI: 10.1002/chem.202303921PMID: 38354298

Check source for accessresearch-article; Journal ArticleOriginal source ↗

Research overview

The text below is the source article’s original abstract under a verified reuse license. cc by

Aggregated α-synuclein (α-syn) protein is a pathological hallmark of Parkinson's disease (PD) and Lewy body dementia (LBD). Development of positron emission tomography (PET) radiotracers to image α-syn aggregates has been a longstanding goal. This work explores the suitability of a pyridothiophene scaffold for α-syn PET radiotracers, where 47 derivatives of a potent pyridothiophene (asyn-44; Kd=1.85 nM) were synthesized and screened against [3H]asyn-44 in competitive binding assays using post-mortem PD brain homogenates. Equilibrium inhibition constant (Ki) values of the most potent compounds were determined, of which three had Ki's in the lower nanomolar range (12-15 nM). An autoradiography study confirmed that [3H]asyn-44 is promising for imaging brain sections from multiple system atrophy and PD donors. Fluorine-18 labelled asyn-44 was synthesized in 6±2 % radiochemical yield (decay-corrected, n=5) with a molar activity of 263±121 GBq/μmol. Preliminary PET imaging of [18F]asyn-44 in rats showed high initial brain uptake (>1.5 standardized uptake value (SUV)), moderate washout (~0.4 SUV at 60 min), and low variability. Radiometabolite analysis showed 60-80 % parent tracer in the brain after 30 and 60 mins. While [18F]asyn-44 displayed good in vitro properties and acceptable brain uptake, troublesome radiometabolites precluded further PET imaging studies. The synthesis and in vitro evaluation of additional pyridothiophene derivatives are underway, with the goal of attaining improved affinity and metabolic stability.

Scientific assessment

01

Research question

Assess the question within the original study’s scope.

02

Methods & sample

Check the source article for study design and sample details.

03

Key findings

An editorially approved findings summary is not yet published for this record.

04

Limitations

Generalizability, bias and clinical meaning require separate assessment.

Methods, samples and clinical conclusions are not inferred from bibliographic metadata.