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Microbiologically Induced Calcite Precipitation Mediated by Sporosarcina pasteurii
Published on: April 16, 2016
Mucins and calcium phosphate precipitates additively stimulate cholesterol crystallization
A A van den Berg1, J D van Buul, G N Tytgat
1Department of Gastrointestinal and Liver Diseases, Academic Medical Center at the University of Amsterdam, The Netherlands.
Journal of Lipid Research
|September 19, 1998
Summary
Human biliary mucins and calcium salt precipitates significantly accelerate cholesterol gallstone formation. Other proteins like calcium binding protein (CBP) have minimal impact on this rapid crystallization process.
Area of Science:
- Bile acid and lipid metabolism
- Gastroenterology and Hepatology
Background:
- Human biliary mucin and calcium binding protein (CBP) are found in cholesterol gallstones.
- These proteins are implicated in the formation of calcium salt precipitates and cholesterol crystals.
Purpose of the Study:
- To investigate how physiological concentrations of mucin and CBP regulate cholesterol crystallization in model bile.
- To determine the influence of calcium ions and calcium phosphate precipitates on cholesterol crystallization in the presence and absence of these proteins.
Main Methods:
- Polarizing light microscopy and nephelometry were used to assess cholesterol crystallization.
- Model biles supersaturated with cholesterol and calcium salts were utilized.
Main Results:
- Calcium phosphate precipitates strongly stimulated cholesterol crystallization compared to soluble calcium.
- Human biliary mucins also stimulated crystallization and additively increased cholesterol crystal mass with calcium salts.
- In the presence of mucins, calcium phosphate precipitates induced near-complete cholesterol crystallization within one day, irrespective of CBP or human serum albumin (HSA).
Conclusions:
- Calcium salt precipitates combined with human biliary mucins are potent inducers of rapid and complete cholesterol crystallization in model bile.
- Human biliary calcium binding proteins (CBP) and HSA show minimal influence on this mucin-driven crystallization process.
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