LZ-106, a potent lysosomotropic agent, causing TFEB-dependent cytoplasmic vacuolization

Area of Science:

• Cell Biology
• Molecular Biology
• Pharmacology

Background:

• Cytoplasmic vacuolization is a cellular response to various agents.
• Lysosomotropic agents accumulate in acidic organelles and can disrupt lysosomal function.

Purpose of the Study:

• To investigate the mechanism of LZ-106-induced cytoplasmic vacuolization in H460 cells.
• To determine the role of lysosomal dysfunction and TFEB activation in this process.

Main Methods:

• Cell culture (H460 cells)
• Fluorescence microscopy to track LZ-106 localization
• Measurement of vacuolar pH and lysosomal membrane integrity
• Western blotting for lysosomal protein expression
• TFEB knockdown experiments

Main Results:

• LZ-106 accumulated in acidic organelles, inducing lysosomal stress (pH increase, membrane damage).
• Vacuoles showed characteristics of late endosomes/lysosomes (LAMP1, RAB7 positive).
• LZ-106 altered expression of lysosomal proteins (LAMP1, EEA1, Cathepsin B) and activated TFEB.
• TFEB knockdown reversed LZ-106-induced vacuolization.

Conclusions:

• LZ-106's lysosomotropic properties lead to lysosomal dysfunction and TFEB activation.
• This activation drives cytoplasmic vacuolization in H460 cells.
• LZ-106 represents a novel tool for studying lysosomal pathways and TFEB regulation.