Oleic acid-induced cholelithiasis in rabbits. Changes in bile composition and gallbladder morphology

Area of Science:

• Gastroenterology
• Hepatology
• Cell Biology

Background:

• Gallstone formation is a complex process involving bile composition and gallbladder function.
• Understanding the early biochemical and morphological changes in the gallbladder is crucial for preventing gallstones.

Purpose of the Study:

• To investigate the effects of oleic acid feeding on bile acid metabolism and gallbladder morphology in rabbits.
• To elucidate the role of allodeoxycholic acid in gallstone formation.

Main Methods:

• Rabbits were fed oleic acid, and bile and gallbladder tissues were analyzed.
• Bile acid concentrations, bile salt pool size, and de novo synthesis were measured.
• Cholesterol saturation in bile was assessed.
• Gallbladder epithelium was examined for morphological changes.

Main Results:

• Oleic acid feeding increased bile allodeoxycholic acid concentration and bile salt pool size.
• De novo hepatic bile acid synthesis decreased, while cholesterol saturation in bile increased.
• Gallstones formed were primarily composed of allodeoxycholic acid salts.
• Morphological changes in the gallbladder included increased cell proliferation, mucus hypersecretion, and formation of Rokitansky-Aschoff sinuses.

Conclusions:

• Oleic acid feeding promotes gallstone formation by altering bile acid metabolism and inducing reactive changes in the gallbladder epithelium.
• Allodeoxycholic acid plays a significant role in the composition of diet-induced gallstones.
• The observed gallbladder changes are critical early events preceding gallstone formation.