Gallstones, cholesterol-rich

The Role of Bile Acids in Cholesterol-Rich Gallstone Formation... 

Trautwein, E. A., Jurgensen, U., and Erbersdobler, H. F. (1997). Cholesterol-lowering and gallstone-preventing action of chitosans with different degrees of deacetylation in hamsters fed cholesterol-rich diets. Nutr. Res. 17,1053-1065. 

Scorbutic guinea pigs develop hypercholesterolemia, which may lead to the development of cholesterol-rich gallstones. This is largely the result of impaired activity of cholesterol 7-hydroxylase, which is an ascorbate-dependent enzyme (Section 13.3.8), resulting in reduced oxidation of cholesterol to bUe acids. There is no evidence that increased intakes of vitamin C above requirements result in increased cholesterol catabolism. 

The first description of cholesterol was written by a French scientist by the name of Poulletier de la Salle (dates not available), who isolated the compound from gallstones, a rich source of the substance. In 1816, de la Salle s compatriot Michel Eugene Chevreul (1786-1889) suggested the name of cholesterine for cholesterol, combining the French words for... 

Thus only radiolucent cholesterol-rich gallstones may be treated medically, while radioopaque pigment stones are insoluble... 

There are multiple ways by which an increase in the percentage DCA in bile may pre-dispose to cholesterol gallstone formation. Carulli et al. showed that DCA-rich bile induces biliary cholesterol hyper-secretion when compared with other bile acids (Graph 8.6). This is likely to be due to the greater hydro-phobicity and detergent efiect of DCA, which would be able to solubilise the lipids in the canalicular cell wall more readily. It may well explain why there have been linear relationships demonstrated between the percentage DCA in bile and (i) the mole percentage cholesterol and (ii) the cholesterol saturation index in bile. This may also explain why there is a link between the... 

Bile is a mixture of electrolytes, bile acids, cholesterol, phospholipids and bilirubin. Adults produce between 400 and 800 ml of bile daily. Hepatocytes secrete bile into canaliculi, then into bile ducts, where it is modified by addition of a bicarbonate-rich secretion from ductal epithelial cells. Further modification occurs in the gall bladder, where it is concentrated up to fivefold, through absorption of water and electrolytes. Gallstones, most of which are composed... 

P5. Park, Y. H., Igimi, H., and Carey, M. C., Dissolution of human cholesterol gallstones in simulated chenodeoxycholate-rich and ursodeoxycholate-rich biles. Gastroenterology 87, 150-158 (1984). 

Cholesterol, one of the most widely occurring steroids, can be isolated by extraction of nearly all animal tissues. Human gallstones are a particularly rich source. 

It is thought that the body synthesizes the phospholipids that it requires as long as there is a sufficient body supply of methionine, magnesium, protein, polyunsaturated fatty acids, and vitamin B-6 (pyridoxine). However, this may not be the case when the feeing of diets rich in polyunsaturated fats causes a rise in the cholesterol content of bile, which may lead to gallstones. It htis been reported that the feeding of lecithin raised the levels of phospholipid in the bile of patients afflicted with gallstones."... 

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