Synthesis and characterization of high affinity fluorogenic α-synuclein probes.

Area of Science:

• Neuroscience
• Chemical Biology
• Molecular Imaging

Background:

• Alpha-synuclein (α-synuclein) aggregation is a hallmark of neurodegenerative synucleinopathies.
• Fluorescent probes are crucial for visualizing α-synuclein pathology in vitro and in vivo.
• Developing specific and sensitive probes remains a challenge.

Purpose of the Study:

• To investigate benzofuranone as a scaffold for designing fluorescent probes targeting α-synuclein.
• To evaluate the binding affinity and specificity of these novel probes to α-synuclein aggregates.
• To assess the probes' utility in distinguishing different pathological inclusions in post-mortem brain tissue.

Main Methods:

• Synthesis and characterization of benzofuranone-based small molecules.
• In vitro assays to determine binding affinity to α-synuclein fibrils.
• Fluorescence microscopy and spectroscopy to assess probe performance.
• Application of probes to post-mortem human brain tissue with various synucleinopathies.

Main Results:

• Benzofuranone compounds demonstrated high affinity for α-synuclein.
• Probes exhibited a fluorescent "turn-on" response upon binding to α-synuclein fibrils.
• Distinct binding patterns were observed for Lewy bodies, Lewy neurites, and glial cytoplasmic inclusions.
• The probes successfully visualized α-synuclein pathology in post-mortem brain tissue.

Conclusions:

• Benzofuranone derivatives show significant potential as specific fluorescent probes for α-synuclein.
• These probes can differentiate between various α-synuclein aggregate types.
• The findings suggest conformational differences in α-synucleinopathies and distinct binding sites for small molecules.