Increased saturation of the fatty acids in the sn-2 position of phospholipids reduces cholesterol crystallization in model biles

Yehuda Ringel, Giora J. Sömjen, Fred M. Konikoff, Ruth Rosenberg, Tuvia Gilat

Research output: Contribution to journalArticlepeer-review

Abstract

Changes in the molecular structure of biliary phospholipids were shown to have major effects on cholesterol solubility, carriers and crystallization in human and model biles. This study investigated systematically the effects of varying saturation of the phosphatidylcholine (PC) sn-2 fatty acid on the cholesterol crystallization process in 3 different model biles. Twenty % of the egg PC (EPC) in these biles were replaced by synthetic PC's with 16:0-18:0, 16:0-18:1, or 16:0-18:2 fatty acyl chains. With 18:0 in the sn-2 position, the crystal observation time (COT) was prolonged from 2 days in the control EPC solution to 14 days (P < 0.05). The crystal growth rate (CGR) was reduced from 0.1 OD/day to unmeasurable levels, and the total crystal mass on day 14 decreased by 86%. The introduction of one (18:1), and two (18:2) double bonds in the sn-2 fatty acid rapidly reversed these effects. Ultracentrifugal analysis showed precipitable cholesterol as monohydrate crystals. In the 16:0-18:0 test solution, most of the precipitable cholesterol remained in the supersaturated multilamellar vesicles. Saturation of the biliary PC sn-2 fatty acyl chain prolongs the COT, slows the CGR, reduces the crystal mass, and extends cholesterol solubility in multilamellar vesicles. Desaturation of the sn-2 fatty acid reverses these effects.

Original languageEnglish
Pages (from-to)293-300
Number of pages8
JournalBiochimica et Biophysica Acta - Lipids and Lipid Metabolism
Volume1390
Issue number3
DOIs
StatePublished - 23 Feb 1998

Keywords

  • Cholesterol crystallization
  • Fatty acyl saturation
  • Model bile
  • Phospholipid species

Fingerprint

Dive into the research topics of 'Increased saturation of the fatty acids in the sn-2 position of phospholipids reduces cholesterol crystallization in model biles'. Together they form a unique fingerprint.

Cite this