OXYSTEROL MEDIATED CHANGES IN FATTY-ACID DISTRIBUTION AND LIPID-SYNTHESIS IN CULTURED BOVINE AORTIC SMOOTH-MUSCLE CELLS

We studied the actions of oxysterols on fatty acid distribution and lipid synthesis in cultured bovine aortic smooth muscle cells. Cultures were labeled with [1-14C] arachidonate or [1-14C]oleate. During a 24-hr incubation, 25-or 22R-hydroxycholesterol enhanced the incorporation of label into triglycerides, concomitant with a reduction in the labeling of phospholipids. Cholestantriol or 20-hydroxycholesterol had the opposite effects. They caused a higher incorporation of radiolabel into phospholipids and a reduction of labeling of triacylglycerols. Similar changes were seen in cells labeled with [1-14C]acetate. Therefore, we conclude that oxysterols can promote changes in the distribution of fatty acids between neutral lipids and phospholipids through mechanisms that still need to be clarified. © 1985 American Oil Chemists' Society (AOCS).