Cholesterol (CH) crystal (C) nucleation paths in human gallbladder bile are identical to model bile: Increased secondary bile salts (BS) and CH saturation index (CSI) are partly responsible for accelerating CH nucleation

In the present study, the stability of the most essential biliary parameters of human gallbladder bile at -18°C was examined over several months. In 12 patients with gallstone disease (10 female, two male; 52.1±13.3 years of age), bile was obtained through fine needle puncture of the gallbladder under local anesthetic. The concentrations of total lipids, cholesterol, phospholipids and bile acids, and the cholesterol saturation index and crystal appearance time were determined before and after freezing over a mean period of 4.38±2.9 months. Gallbladder bile obtained by fine needle puncture has proved to be of excellent quality. The total lipid concentration was unchanged before (8.30±4.16 g/dL) and after freezing (9.16±4.54 g/dL, P=0.6027). The biliary cholesterol, phospholipids and bile acid concentrations, and cholesterol saturation index showed no statistically significant differences before and after freezing. A significant difference arises in the context of subdivision of the group to the nucleation time. Before freezing, most patients had a nucleation time between five and eight days, which shortened to between one and four days after thawing (P=0.0100). The authors conclude that, with the exception of the nucleation time, human gallbladder bile can be stored at -18°C for four months with stability of major lipid components.

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Cholesterol gallstone pathogenesis: a study of potential nucleating agents for cholesterol crystal formation in bile

Clinical Science ◽

10.1042/cs0680589 ◽

1985 ◽

Vol 68 (5) ◽

pp. 589-596 ◽

Cited By ~ 24

Author(s):

M. J. Whiting ◽

J. McK. Watts

Keyword(s):

Gallbladder Bile ◽

Crystal Formation ◽

Nucleating Agents ◽

Cholesterol Crystal ◽

Calcium Salts ◽

Human Gallbladder ◽

Cholesterol Crystals ◽

Cholesterol Gallstones ◽

Cholesterol Monohydrate ◽

Model Bile

1. Cholesterol monohydrate crystal formation was measured quantitatively in model bile solutions, which were supersaturated with cholesterol, by a radiochemical method and qualitatively in human gallbladder bile by polarizing microscopy. 2. Various agents, which have been postulated to act as nucleating factors for cholesterol crystal and gallstone formation, were added to bile and their effect on the appearance of cholesterol crystals was determined. These agents included calcium salts found in gallstones (calcite, aragonite, apatite, bilirubinate), Escherichia coli bacteria, pigment residues from cholesterol gallstones, bilirubin and several mucin preparations. 3. Human gallbladder bile, which was collected from patients with and without cholesterol gallstones, was also mixed with model bile to examine whether nucleating or anti-nucleating factors were present. 4. None of the agents tested markedly and consistently promoted cholesterol monohydrate crystal formation in model or human bile, except seed crystals of cholesterol monohydrate which were used as a control. Human gallbladder bile from obese patients without gallstones delayed the appearance of cholesterol crystals in model bile solutions, whereas gallbladder bile from gallstone patients did not. 5. These results do not provide experimental support for the hypothesis that calcium salts and pigment material found in gallstones, or gallbladder mucin at concentrations less than 10 mg/ml, act as nucleating agents for cholesterol crystal and stone formation. The difference between gallbladder biles from patients with and without gallstones in their propensity to form cholesterol crystals may be due to the presence of an anti-nucleating factor in normal bile.

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Fibronectin in human gallbladder bile: cholesterol pronucleating and/or mucin "link" protein?

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1994.267.3.g393 ◽

1994 ◽

Vol 267 (3) ◽

pp. G393-G400 ◽

Cited By ~ 2

Author(s):

J. F. Miquel ◽

C. Von Ritter ◽

R. Del Pozo ◽

V. Lange ◽

D. Jungst ◽

...

Keyword(s):

Cholesterol Gallstone ◽

Gallstone Disease ◽

Gallstone Formation ◽

Gallbladder Bile ◽

Crystal Formation ◽

Nucleation Time ◽

Human Gallbladder ◽

Link Protein ◽

Wide Range ◽

Model Bile

Some biliary proteins (pronucleators) seem to be essential factors for cholesterol crystal formation and crystal growth in bile. A recent study suggests that fibronectin is such a pronucleator in bile. Fibronectin also seems to closely interact with intestinal mucin. Since biliary mucin plays an important role in gallstone formation, such an interaction in bile may be of relevance in cholesterol gallstone formation. To more clearly elucidate the role of fibronectin in cholesterol gallstone disease, we measured the concentration of fibronectin in native bile of cholesterol gallstone patients and checked its influence on the cholesterol nucleation time of model bile. We further looked for a molecular interaction between biliary fibronectin and gallbladder mucin. We found that fibronectin is present in gallbladder bile of gallstone patients in low concentrations (2.6 +/- 1.2 micrograms/ml). Bile fibronectin did not interact with gallbladder mucin. Moreover, in a wide range of concentrations fibronectin had no influence on the nucleation time of model bile. We conclude that fibronectin does not seem to play a major role in cholesterol gallstone disease.

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Partial characterization of a nonmicellar system of cholesterol solubilization in bile

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1987.252.3.g374 ◽

1987 ◽

Vol 252 (3) ◽

pp. G374-G383 ◽

Cited By ~ 1

Author(s):

S. P. Lee ◽

H. Z. Park ◽

H. Madani ◽

E. W. Kaler

Keyword(s):

Bile Salts ◽

Saturation Index ◽

Buoyant Density ◽

Gallbladder Bile ◽

Elastic Light Scattering ◽

Cholesterol Solubilization ◽

Cholesterol Saturation Index

We have shown that there were two distinctly separate cholesterol-containing fractions in human hepatic and gallbladder bile. In addition to mixed micelles that were composed of bile salts, cholesterol, and phospholipids and measured at approximately 25 A by quasi-elastic light scattering spectroscopy, there was a nonmicellar fraction made up of cholesterol and phospholipids with no, or only trace amount of bile salts. This fraction had a mean hydrodynamic radius of 600 A. When studied with electron microscopy, the fraction consisted of particle spherical in shape that measured 900–1,300 A in diameter and were monodisperse. This form of cholesterol had a low buoyant density of less than 1.05 g/ml by density gradient ultracentrifugation and eluted as a macromolecular aggregate (mol wt greater than 200,000) employing Sephadex G-75 chromatography. The quantity of nonmicellar cholesterol in bile correlated positively with the cholesterol saturation index (r = 0.649; P less than 0.001) and inversely with relative bile salt concentration (r = -0.572, P less than or equal to 0.03) and total lipid concentration (r = -0.844, P less than 0.0001). In vitro and in vivo addition of bile salts resulted in a shift of nonmicellar cholesterol to micellar cholesterol. In hepatic bile, nonmicellar cholesterol was the predominant and sometimes the exclusive form of cholesterol transport. When nucleation experiments were performed on gallbladder bile samples, the cholesterol that had nucleated were almost exclusively derived from the nonmicellar fraction.

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