The class
CETP mRNA abundance in human adipose tissue tracks membrane cholesterol content, not stored lipid droplet cholesterol (J Lipid Res 1995)
Original title: Cholesteryl ester transfer protein (CETP) mRNA abundance in human adipose tissue: relationship to cell size and membrane cholesterol content
Quantifying CETP mRNA in subcutaneous adipose tissue from 10 women using solution hybridization RNase protection assay, and measuring membrane and lipid-droplet cholesterol by gas chromatography, researchers found CETP mRNA abundance correlated significantly with membrane cholesterol as a fraction of membrane protein (r=0.67, P=0.031), with membrane cholesterol to core triglyceride ratio (r=0.77, P=0.009), and most strongly with the ratio of membrane to core cholesterol (r=0.91, P=0.0002), while correlating negatively with lipid droplet cholesterol and triglyceride. Adipose tissue in organ culture secreted CETP into the medium, and incubation with cholesterol-rich chylomicron remnants produced a dose-dependent increase in secretion, supporting the hypothesis that CETP gene expression is regulated by a specific cellular membrane sterol pool rather than total cellular cholesterol.
Original abstract
Cholesteryl ester transfer protein (CETP) has a well-defined role in plasma neutral lipid transport. CETP synthesized by human adipose tissue may contribute to the plasma CETP pool. CETP mRNA abundance increases in subcutaneous adipose tissue in response to cholesterol feeding and we have hypothesized that CETP gene expression is regulated by a specific pool of cellular sterol. In the present study, we have quantified CETP mRNA levels in subcutaneous adipose tissue of 10 female subjects using a solution hybridization RNase protection assay. Particulate (membrane cholesterol) and lipid droplet cholesterol (core cholesterol) were determined by gas chromatography. CETP mRNA abundance in these adipose tissue specimens correlated significantly with membrane cholesterol expressed as a fraction of membrane protein (r = 0.67, P = 0.031). There was also a linear relationship between CETP mRNA abundance and membrane cholesterol to core triglyceride ratio (r = 0.77, P = 0.009) and a strong correlation between the percentage of cellular cholesterol in the membrane fraction (ratio of membrane to core cholesterol) and CETP mRNA abundance (r = 0.91, P = 0.0002). In contrast, there was a negative relationship between each of lipid droplet cholesterol and triglyceride and CETP mRNA levels. Human adipose tissue maintained in organ culture for several days was shown to secrete CETP into the culture medium. Incubation with cholesterol-rich chylomicron remnants elicited a dose-dependent increase in both membrane and core cholesterol and a concomitant increase in the level of CETP mRNA. These studies demonstrate that adipose tissue CETP mRNA abundance is a function of membrane cholesterol concentration rather than lipid droplet cholesterol and that CETP mRNA increases with adipocyte cholesterol enrichment via chylomicron remnants. CETP gene expression is highest in small lipid-poor adipocytes, suggesting that CETP synthesized and secreted by adipocytes may have a role in promoting cellular cholesterol accumulation.
Summary written by cetpinhibition.org from the published abstract; figures as published. Page updated 19 August 2026. Methods.