Regulation of cholesterol ester transfer protein by dietary lipids

Abstract

The mechanism of the regulation of cholesterol ester transfer protein by dietary fats and cholesterol was investigated using human cholesterol ester transfer protein transgenic mice fed monounsaturated fatty acid and saturated fatty acid enriched diets with or without cholesterol. Cholesterol inhibited protein activity and hepatic mRNA abundance in the monounsaturated fatty acid diet. However, cholesterol enhanced protein activity but had no effect on hepatic mRNA abundance in the saturated fatty acid diet. The molecular mechanisms of dietary lipid mediated regulation of the promoter activity of this gene were investigated using chimeric gene constructs harbouring sequential deletions of the gene promoter in SW 872 cell culture. Oleic acid and stearic acid had opposite effects indicating that the type of dietary fat alters gene regulation. There was interaction between cholesterol and fatty acids to regulate cholesterol ester transfer protein.