Tetramic Acid-Derived Blue-Emitting Fluorescent Probe for Selective Lipid Droplet Imaging in Live Cells and Zebrafish

Area of Science:

• Cell Biology
• Biochemistry
• Molecular Imaging

Background:

• Lipid droplets (LDs) are vital organelles for lipid metabolism, crucial for understanding cellular health and disease.
• Accurate imaging of LDs is essential for studying metabolic processes.
• Existing imaging techniques have limitations in live-cell and whole-organism applications.

Purpose of the Study:

• To develop and characterize novel fluorescent tetramic acid derivatives as lipid droplet (LD) markers.
• To evaluate the efficacy of the most promising probe (1a) for live imaging in cellular and whole-organism systems.
• To assess the photophysical properties and cytotoxicity of probe 1a.

Main Methods:

• Synthesis and characterization of four novel fluorescent tetramic acid derivatives.
• Evaluation of probe 1a in multiple cell lines for LD visualization and colocalization studies.
• Photophysical property assessment (photostability, signal-to-noise ratio).
• Cytotoxicity assays at imaging concentrations.
• In vivo imaging studies using a zebrafish model.

Main Results:

• Probe 1a demonstrated clear visualization of intracellular LDs in various cell lines.
• Strong colocalization of probe 1a with established lipid markers (Nile Red, BODIPY 493/503).
• Probe 1a exhibited favorable photophysical properties for fluorescence imaging.
• Minimal acute and delayed cytotoxicity observed at imaging concentrations.
• Successful application of probe 1a for visualizing lipid-rich structures in zebrafish.

Conclusions:

• The novel tetramic acid derivative 1a is a potent fluorescent marker for LDs.
• Probe 1a enables effective live imaging of LDs in both cellular and whole-organism contexts.
• 1a represents a valuable tool for advancing research in lipid metabolism and related diseases.