A comparative study of microstructural development in paired human hepatic and gallbladder biles

Area of Science:

• Gastroenterology
• Biophysics
• Biochemistry

Background:

• Cholesterol gallstones typically form in the gallbladder, rarely in bile ducts, even with lithogenic bile.
• The precise role of bile concentration and proteins in crystallization pathways and microstructural evolution is not fully understood.

Purpose of the Study:

• To investigate the essential lipid microstructures for cholesterol gallstone crystallization.
• To compare microstructural evolution in hepatic and gallbladder bile.

Main Methods:

• Utilized digital light microscopy and cryogenic-transmission electron microscopy.
• Directly visualized time evolution of lipid microstructures in paired hepatic, gallbladder, and diluted gallbladder biles without drying or separation.
• Examined biles from gallstone patients and controls.

Main Results:

• Gallbladder bile showed multilamellar vesicles and spheroidal micelles preceding and during crystallization; vesicle morphology changed before crystallization.
• Hepatic bile exhibited minimal crystallization, with rare multilamellar vesicles.
• Diluted gallbladder bile showed occasional crystallization, differing from native gallbladder and hepatic bile.

Conclusions:

• Maturing multilamellar vesicles appear to precede and initiate crystallization in gallbladder bile.
• Microstructural development is concentration-dependent, but dilution to hepatic bile concentrations does not fully inhibit crystallization.