Synthesis of Thiophene‐Based Optical Ligands That Selectively Detect Tau Pathology in Alzheimer's Disease

• Published in: Chemistry : a European journal Vol. 23; no. 67; pp. 17127 - 17135
• Main Authors: Shirani, Hamid, Appelqvist, Hanna, Bäck, Marcus, Klingstedt, Therése, Cairns, Nigel J., Nilsson, K. Peter R.
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 01.12.2017; Wiley Subscription Services, Inc
• Subjects: Aggregates; Alzheimer's disease; amyloid-beta; Brain; Chemistry; Chemistry, Multidisciplinary; Fluorescence; fluorescent ligands; Ligands; Molecular interactions; Neurodegenerative diseases; Neuroimaging; Neurological diseases; Pathology; Physical Sciences; protein aggregates; Proteins; Science & Technology; Senile plaques; Structure-function relationships; Synthesis; tau aggregates; Tau protein; THIOFLAVIN-T; fluorescent ligands; SPECTRAL ASSIGNMENT; protein aggregates; OLIGOTHIOPHENES; PLAQUES; BETA; amyloid-beta; AMYLOID IMAGING AGENTS; FIBRILS; tau aggregates; Alzheimers disease; BINDING; BRAIN; PET; Alzheimer′s disease
• ISSN: 0947-6539; 1521-3765; 1521-3765
• DOI: 10.1002/chem.201703846

The accumulation of protein aggregates is associated with many devastating neurodegenerative diseases and the development of molecular ligands able to detect these pathological hallmarks is essential. Here, the synthesis of thiophene based optical ligands, denoted bi‐thiophene‐vinyl‐benzothiazoles (bTVBTs) that can be utilized for selective assignment of tau aggregates in brain tissue with Alzheimer's disease (AD) pathology is reported. The ability of the ligands to selectively distinguish tau deposits from the other AD associated pathological hallmark, senile plaques consisting of aggregated amyloid‐β (Aβ) peptide, was reduced when the chemical composition of the ligands was altered, verifying that specific molecular interactions between the ligands and the aggregates are necessary for the selective detection of tau deposits. Our findings provide the structural and functional basis for the development of new fluorescent ligands that can distinguish between aggregated proteinaceous species consisting of different proteins. In addition, the bTVBT scaffold might be utilized to create powerful practical research tools for studying the underlying molecular events of tau aggregation and for creating novel agents for clinical imaging of tau pathology in AD. A specific pathological partner: Bi‐thiophene‐vinyl‐benzothiazoles (bTVBTs) are superior thiophene‐based optical ligands for selective detection of tau pathology in Alzheimer's disease (AD). Alternating distinct chemical motifs of the bTVBT scaffold greatly reduced the ability of the dye to distinguish Aβ and tau deposits, the two pathological hallmarks in AD.