TY - JOUR
T1 - Phospholipid lamellae are cholesterol carriers in human bile
AU - Sömjen, Giora J.
AU - Marikovsky, Yehuda
AU - Wachtel, Ellen
AU - Harvey, P. Robert C.
AU - Rosenberg, Ruth
AU - Strasberg, Steven M.
AU - Gilat, Tuvia
PY - 1990/1/16
Y1 - 1990/1/16
N2 - Cholesterol solubility and precipitation in bile are major factors in the pathogenesis of cholesterol gallstones. At present, mixed micelles and phospholipid vesicles are considered to be the only cholesterol carriers in bile. In this study we present evidence showing that phospholipid lamellae are major cholesterol carriers in human bile. Lamellae are a known aggregational form in pure phospholipid model systems. In the present study, lamellae were demonstrated by electron microscopy after negative staining and by small-angle X-ray diffraction in all human gallbladder bile samples examined. During diffraction experiments, cholesterol was found to crystallize from these lamellae. Cholesterol carriers in bile were separated by high-resolution chromatography and by prolonged ultracentrifugation. Lamellae were shown to solubilize most of the biliary cholesterol; vesicles solubilized a lesser amount; while micelles solubilized only a minor portion. Our data suggest that phospholipid aggregates are the main cholesterol carriers in bile. Bile salts may control the equilibrium between the various aggregational forms of cholesterol-carrying phospholipids.
AB - Cholesterol solubility and precipitation in bile are major factors in the pathogenesis of cholesterol gallstones. At present, mixed micelles and phospholipid vesicles are considered to be the only cholesterol carriers in bile. In this study we present evidence showing that phospholipid lamellae are major cholesterol carriers in human bile. Lamellae are a known aggregational form in pure phospholipid model systems. In the present study, lamellae were demonstrated by electron microscopy after negative staining and by small-angle X-ray diffraction in all human gallbladder bile samples examined. During diffraction experiments, cholesterol was found to crystallize from these lamellae. Cholesterol carriers in bile were separated by high-resolution chromatography and by prolonged ultracentrifugation. Lamellae were shown to solubilize most of the biliary cholesterol; vesicles solubilized a lesser amount; while micelles solubilized only a minor portion. Our data suggest that phospholipid aggregates are the main cholesterol carriers in bile. Bile salts may control the equilibrium between the various aggregational forms of cholesterol-carrying phospholipids.
KW - (Human)
KW - Bile
KW - Biliary cholesterol
KW - Phospholipid lamellae
UR - http://www.scopus.com/inward/record.url?scp=0025097834&partnerID=8YFLogxK
U2 - 10.1016/0005-2760(90)90052-Y
DO - 10.1016/0005-2760(90)90052-Y
M3 - Article
C2 - 2297522
AN - SCOPUS:0025097834
VL - 1042
SP - 28
EP - 35
JO - Biochimica et Biophysica Acta - Lipids and Lipid Metabolism
JF - Biochimica et Biophysica Acta - Lipids and Lipid Metabolism
SN - 0005-2760
IS - 1
ER -